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Carrier air conditioner fault codes

by | Aug 3, 2026

When your Carrier system stops and shows a code, that code is the system telling you roughly where the problem is. Roughly is the key word. A fault code points in a direction, it rarely names the exact fix. Find your system below, tap your code, and it will take you straight to what it means and what to do.

Before you try anything: the only DIY steps that are ever safe are switching the system off at the isolator (and waiting 20 to 30 minutes), cleaning or checking filters, checking the controller settings and batteries, and keeping the outdoor unit clear. Anything behind a panel, anything electrical, and anything involving refrigerant or gas is licensed work. If a code below says switch off and call, please take it at its word.

How to read the tables: 🟢 means there is a safe first step worth trying. 🟡 means book a service, the system needs a technician. 🔴 means switch the system off at the isolator and call us on (02) 4760 0100.

Carrier ducted — inverter models (Table 7-1a)

Where the code shows: Two-character code on the indoor unit's digital display ("digital tube"); indoor LEDs (operation, timer, defrost/fan, alarm) flash alongside.

Tap your code: E8E1E2E3E4E7EEEdF3F4
Code What it means What to do
E8 The indoor fan motor isn't spinning at the speed it's being asked to.
Indoor fan motor speed out of control		 🟡 Book a service. It's safe to try one power-cycle at the isolator first, off for 20 to 30 minutes, then back on.
E1 The indoor and outdoor units have lost contact with each other.
Indoor–outdoor communication channel abnormal		 🟢 Switch the system off at the power isolator, wait 20 to 30 minutes, then switch it back on, communication faults often clear after a power interruption or blackout. If the code returns, book a service.
E2 The room temperature sensor isn't reading properly.
Room temperature sensor circuit abnormal		 🟡 Book a service, a sensor fault needs a technician to test and replace the part.
E3 A pipe (coil) temperature sensor isn't reading properly.
Pipe temperature sensor circuit abnormal (T2 sensor)		 🟡 Book a service, a sensor fault needs a technician to test and replace the part.
E4 A second pipe (coil) temperature sensor isn't reading properly.
Pipe temperature sensor circuit abnormal (T2B sensor)		 🟡 Book a service, a sensor fault needs a technician to test and replace the part.
E7 The control board's stored memory has a fault.
EEPROM malfunction		 🟡 Try one power-cycle at the isolator (off 20 to 30 minutes). If the code comes back, book a service, the control board likely needs attention.
EE The condensate water level alarm has tripped, the drain tray may not be emptying.
Water-level alarm malfunction		 🟡 Switch the system off at the isolator to avoid the drain tray overflowing (with ducted systems it sits in your ceiling space) and book a service.
Ed The outdoor unit has reported a fault.
Outdoor unit malfunction (unspecified)		 🟡 Book a service. It's safe to try one power-cycle at the isolator first, and check nothing is blocking the outdoor unit.
F3 Twin indoor units have lost communication with each other.
Indoor "twins" (paired indoor units) communication malfunction		 🟢 Switch the system off at the isolator, wait 20 to 30 minutes, then switch it back on, communication faults often clear after a power interruption. If the code returns, book a service.
F4 A fault on a twin (paired) indoor unit setup other than lost communication.
Other malfunction of twins configuration		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.

Carrier ducted — fixed-speed models (Table 7-1b)

Where the code shows: Two-character code on the indoor unit's digital display; indoor LEDs flash at 5Hz/1Hz.

Tap your code: E2E3E4E5E7E8
Code What it means What to do
E2 The room temperature sensor isn't reading properly.
Room temperature sensor checking channel abnormal. The truncated left column was recovered by re-extracting the source table with layout preserved.		 🟡 Book a service, a sensor fault needs a technician.
E3 The pipe (coil) temperature sensor isn't reading properly.
Pipe temperature sensor checking channel abnormal. The truncated left column was recovered by re-extracting the source table with layout preserved.		 🟡 Book a service, a sensor fault needs a technician.
E4 The outdoor temperature sensor isn't reading properly.
Outdoor TEMP. sensor checking channel abnormal. Corrected: the earlier 'second pipe/coil sensor' guess (mirrored from the inverter table) was wrong; on the fixed-speed table E4 is the outdoor sensor.		 🟡 Book a service, a sensor fault needs a technician.
E5 The pump temperature sensor isn't reading properly.
"Pump temperature sensor malfunction" as written in the source, unusual wording, most likely relates to the condensate/water system		 🟡 Book a service, a sensor fault needs a technician.
E7 The control board's stored memory has a fault.
EEPROM malfunction		 🟡 Try one power-cycle at the isolator (off 20 to 30 minutes). If the code comes back, book a service.
E8 The condensate water level alarm has tripped, the drain tray may not be emptying.
Water-level alarm malfunction		 🟡 Switch the system off at the isolator to avoid the drain tray overflowing and book a service.

Alpha AS10-15 (cooling-only models)

Where the code shows: Indoor unit indicator lamps: Operation and Timer (flash / on / off combinations).

Tap your code: Operation flashing, Timer offOperation flashing, Timer onOperation off, Timer flashingOperation on, Timer flashingOperation flashing, Timer flashing
Code What it means What to do
Operation flashing, Timer off The indoor fan hasn't run at its commanded speed for over a minute.
Indoor fan speed out of control for over 1 minute. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.
Operation flashing, Timer on The room or indoor-coil temperature sensor circuit is open or shorted.
Indoor room temp or evaporator sensor open/short circuit. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🟡 Book a service, a sensor fault needs a technician.
Operation off, Timer flashing The compressor's overcurrent protection has tripped four times.
Compressor over-current protection occurred 4 times. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🔴 Switch the system off at the isolator and call us, don't keep restarting it.
Operation on, Timer flashing The control board's stored memory has a fault.
EEPROM error. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🟡 Try one power-cycle at the isolator (off 20 to 30 minutes). If it comes back, book a service.
Operation flashing, Timer flashing The control board can't detect the mains zero-crossing signal, a board-level fault.
No over-zero (zero-crossing) signal. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.

Alpha AS15H (heat pump model)

Where the code shows: Indoor unit indicator lamps: Operation, Timer and Defrost (flash / on / off combinations).

Tap your code: Operation flashing, Timer off, Defrost flashingOperation off, Timer flashing, Defrost flashingOperation flashing, Timer flashing, Defrost flashingOperation off, Timer off, Defrost flashingOperation off, Timer flashing, Defrost offOperation on, Timer flashing, Defrost off
Code What it means What to do
Operation flashing, Timer off, Defrost flashing The compressor's overcurrent protection has tripped four times.
Compressor over-current protection occurred 4 times. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🔴 Switch the system off at the isolator and call us, don't keep restarting it.
Operation off, Timer flashing, Defrost flashing The indoor fan hasn't run at its commanded speed for over a minute.
Indoor fan speed out of control for over 1 minute. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.
Operation flashing, Timer flashing, Defrost flashing The control board can't detect the mains zero-crossing signal, a board-level fault.
No over-zero (zero-crossing) signal. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.
Operation off, Timer off, Defrost flashing The indoor-coil temperature sensor circuit is open or shorted.
Indoor evaporator temperature sensor open/short circuit. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🟡 Book a service, a sensor fault needs a technician.
Operation off, Timer flashing, Defrost off The room temperature sensor circuit is open or shorted.
Indoor room temperature sensor open/short circuit. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🟡 Book a service, a sensor fault needs a technician.
Operation on, Timer flashing, Defrost off The control board's stored memory has a fault.
EEPROM error. Lamp-to-fault pairing confirmed by layout re-extraction of the source table.		 🟡 Try one power-cycle at the isolator (off 20 to 30 minutes). If it comes back, book a service.

Alpha AS35C/H — indoor unit

Where the code shows: Indoor unit indicator lamps flashing at 5Hz (operation / timer / defrost — defrost lamp doubles as fan lamp on cooling-only units — plus auto).

Tap your code: Operation + Timer + Defrost lamps flashing (5Hz)Timer lamp flashing (5Hz)Operation lamp flashing (5Hz)Defrost lamp flashing (5Hz)Defrost + Auto lamps flashing (5Hz)
Code What it means What to do
Operation + Timer + Defrost lamps flashing (5Hz) The compressor's current protection has tripped four times.
Current protection (PRCUR1) occurred 4 times. In the AS35C/H table the pattern is Operation + Timer + Defrost; the AS15H copy of the same list adds the auto lamp, confirmed by layout re-extraction.		 🔴 Switch the system off at the isolator and call us, don't keep restarting it.
Timer lamp flashing (5Hz) The room temperature sensor circuit is open or shorted.
Room temperature sensor open/short		 🟡 Book a service, a sensor fault needs a technician.
Operation lamp flashing (5Hz) The indoor-coil temperature sensor circuit is open or shorted.
Evaporator temperature sensor open/short		 🟡 Book a service, a sensor fault needs a technician.
Defrost lamp flashing (5Hz) The outdoor-coil temperature sensor circuit is open or shorted.
Condenser temperature sensor open/short		 🟡 Book a service, a sensor fault needs a technician.
Defrost + Auto lamps flashing (5Hz) The outdoor unit has gone into a protection mode (for example its outdoor temperature sensor or the power phase order).
Outdoor unit protection (outdoor temp sensor, phase order etc.). Both copies of the table agree on Defrost + Auto, confirmed by layout re-extraction.		 🟡 Book a service. It's safe to try one power-cycle at the isolator first, and check nothing is blocking the outdoor unit.

Alpha AS35C/H — outdoor unit

Where the code shows: Outdoor unit LED: counts a number of flashes, pauses 2 seconds, repeats (steady on = normal running).

Tap your code: 5 flashes4 flashes3 flashes2 flashes1 flash
Code What it means What to do
5 flashes The outdoor unit has lost contact with the indoor unit.
Communication error		 🟢 Switch the system off at the isolator, wait 20 to 30 minutes, then switch it back on, communication faults often clear after a power interruption. If it returns, book a service.
4 flashes The power supply phases are connected in the wrong order, so the unit is protecting itself.
Phase order protection (three-phase supply)		 🟡 Book a service, this is an electrical supply issue a technician needs to check. Don't keep restarting the unit.
3 flashes The refrigerant circuit pressure has gone outside safe limits and the unit has shut itself down.
Pressure protection		 🔴 Switch the system off at the isolator and call us, pressure faults can point to a refrigerant problem.
2 flashes The outdoor-coil temperature sensor circuit is open or shorted.
Condenser temperature sensor open/short		 🟡 Book a service, a sensor fault needs a technician.
1 flash The indoor unit has reported a problem.
Indoor unit abnormal		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.

Alpha Inverter

Where the code shows: Four indoor LEDs in the order defrost, timer, auto, operation (O = on, X = off, ☆ = flash) — column order confirmed from the table's second header line (LED2 defrost / LED1 timer / LED3 auto / LED4 operation) in a layout re-extraction. Outdoor: L4 flashing at 1Hz = fault, steady on = running, 0.5Hz = standby..

Tap your code: X X O ☆O X X ☆X O X ☆X O O ☆O O O ☆O O ☆ ☆☆ X O ☆X X ☆ ☆☆ ☆ ☆ ☆
Code What it means What to do
X X O ☆ The unit is in its mould-prevention (drying) protection mode rather than a breakdown.
Listed as "mold protection" in the fault table, the anti-mould/self-dry routine; it sits in the error list, so treat a persistent pattern with caution. Pattern-to-meaning pairing confirmed by layout re-extraction.		 🟢 Let the cycle finish. If the lamps stay like this or the unit won't run afterwards, switch it off at the isolator for 20 to 30 minutes; if it persists, book a service.
O X X ☆ The top of the compressor has overheated and the unit has shut down to protect it.
Compressor top temperature protection		 🔴 Switch the system off at the isolator and call us, overheating can point to a refrigerant or compressor problem.
X O X ☆ The outdoor temperature sensor circuit is open or shorted.
Outdoor temperature sensor open/short circuit		 🟡 Book a service, a sensor fault needs a technician.
X O O ☆ The unit has shut down because the power supply voltage is too high or too low, or it's overloaded.
Overload or under/over-voltage protection		 🟡 Switch off at the isolator for 20 to 30 minutes and try again, voltage dips after grid events can trip this. If it keeps happening, book a service.
O O O ☆ The room or indoor-coil temperature sensor circuit is open or shorted.
Room or evaporator temperature sensor open/short circuit		 🟡 Book a service, a sensor fault needs a technician.
O O ☆ ☆ The indoor fan isn't spinning at the speed it's being asked to.
Fan speed beyond control		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.
☆ X O ☆ The control board can't detect the mains zero-crossing signal, a board-level fault.
Zero-crossing examination error		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.
X X ☆ ☆ The control board's stored memory has a fault.
EEPROM data error		 🟡 Try one power-cycle at the isolator (off 20 to 30 minutes). If it comes back, book a service.
☆ ☆ ☆ ☆ The indoor and outdoor units have lost contact with each other.
Indoor/outdoor communication protection		 🟢 Switch the system off at the isolator, wait 20 to 30 minutes, then switch it back on, communication faults often clear after a power interruption. If it returns, book a service.

Elite 42LUVH055N / 42LUVH065N (N series)

Where the code shows: E/P code on the indoor unit display.

Tap your code: E0E1E2E3E5E6E7P0P1P2P4
Code What it means What to do
E0 The control board's stored memory has a fault.
EEPROM parameter error		 🟡 Try one power-cycle at the isolator (off 20 to 30 minutes). If the code comes back, book a service.
E1 The indoor and outdoor units have lost contact with each other.
Indoor/outdoor communication protection		 🟢 Switch the system off at the isolator, wait 20 to 30 minutes, then switch it back on, communication faults often clear after a power interruption. If the code returns, book a service.
E2 The control board can't detect the mains zero-crossing signal, a board-level fault.
Zero-crossing signal error		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.
E3 The indoor fan isn't spinning at the speed it's being asked to.
Fan speed out of control		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.
E5 The outdoor temperature sensor circuit is open or shorted.
Outdoor temperature sensor open/short circuit		 🟡 Book a service, a sensor fault needs a technician.
E6 The room or indoor-coil temperature sensor circuit is open or shorted.
Room or evaporator temperature sensor open/short circuit		 🟡 Book a service, a sensor fault needs a technician.
E7 The outdoor unit's fan has a problem and its protection has kicked in.
Outdoor unit fan protection		 🟡 Check nothing is blocking or tangled in the outdoor unit (from the outside only), then book a service.
P0 The inverter power module has shut down to protect itself from an electrical fault.
Module protection (inverter power module / IPM)		 🔴 Switch the system off at the isolator and call us, don't keep restarting it.
P1 The unit has shut down because the power supply voltage is too high or too low.
Over-voltage or under-voltage protection		 🟡 Switch off at the isolator for 20 to 30 minutes and try again, voltage dips after grid events can trip this. If it keeps happening, book a service.
P2 The top of the compressor has overheated and the unit has shut down to protect it.
Compressor top temperature protection		 🔴 Switch the system off at the isolator and call us, overheating can point to a refrigerant or compressor problem.
P4 The electronics that drive the inverter compressor have reported a fault.
Inverter compressor drive error. E4 and P3 are reserved (unused) on this series.		 🔴 Switch the system off at the isolator and call us, repeated restarts can stress the compressor.

Elite 42LUVH075N

Where the code shows: Indoor lamps in on/off/flash combinations, listed in the source column order Defrost · Timer · Auto · Operation (On = steady, X = off, ☆ = flash at 5Hz). The operation lamp flashes in every fault pattern..

Tap your code: Def On · Timer On · Auto On · Op OnDef ☆ · Timer ☆ · Auto ☆ · Op ☆Def X · Timer On · Auto X · Op ☆Def On · Timer On · Auto On · Op ☆Def X · Timer X · Auto On · Op ☆Def X · Timer On · Auto On · Op ☆Def On · Timer X · Auto X · Op ☆Def On · Timer X · Auto On · Op ☆Def On · Timer X · Auto ☆ · Op ☆
Code What it means What to do
Def On · Timer On · Auto On · Op On The control board's stored memory has a fault.
EEPROM parameter error		 🟡 Try one power-cycle at the isolator (off 20 to 30 minutes). If it comes back, book a service.
Def ☆ · Timer ☆ · Auto ☆ · Op ☆ The indoor and outdoor units have lost contact with each other.
Indoor/outdoor communication protection		 🟢 Switch the system off at the isolator, wait 20 to 30 minutes, then switch it back on, communication faults often clear after a power interruption. If it returns, book a service.
Def X · Timer On · Auto X · Op ☆ The outdoor temperature sensor circuit is open or shorted.
Outdoor temperature sensor open/short circuit		 🟡 Book a service, a sensor fault needs a technician.
Def On · Timer On · Auto On · Op ☆ The room or indoor-coil temperature sensor circuit is open or shorted.
Room or evaporator temperature sensor open/short circuit		 🟡 Book a service, a sensor fault needs a technician.
Def X · Timer X · Auto On · Op ☆ The inverter power module has shut down to protect itself from an electrical fault.
Module protection (inverter power module / IPM)		 🔴 Switch the system off at the isolator and call us, don't keep restarting it.
Def X · Timer On · Auto On · Op ☆ The unit has shut down because the power supply voltage is too high or too low.
Over-voltage or under-voltage protection		 🟡 Switch off at the isolator for 20 to 30 minutes and try again, voltage dips after grid events can trip this. If it keeps happening, book a service.
Def On · Timer X · Auto X · Op ☆ The top of the compressor has overheated and the unit has shut down to protect it.
Compressor top temperature protection		 🔴 Switch the system off at the isolator and call us, overheating can point to a refrigerant or compressor problem.
Def On · Timer X · Auto On · Op ☆ The outdoor temperature is too low for the unit to run, so it's protecting itself.
Outdoor temperature low protection (075N only, not in the 055N/065N code list)		 🟡 This usually clears when the weather warms up. If it appears in mild conditions, book a service.
Def On · Timer X · Auto ☆ · Op ☆ The electronics that drive the inverter compressor have reported a fault.
Inverter compressor drive error		 🔴 Switch the system off at the isolator and call us, repeated restarts can stress the compressor.

Elite 025N-1 to 075N-1 (N-1 series)

Where the code shows: E/P code on the indoor unit display.

Tap your code: E0E1E2E3E5E6E7P0P1P2P4
Code What it means What to do
E0 The control board's stored memory has a fault.
EEPROM parameter error. Manual's own first step is a power-off/on reset; if it recurs, the indoor PCB is suspect.		 🟡 Try one power-cycle at the isolator (off 20 to 30 minutes). If the code comes back, book a service.
E1 The indoor and outdoor units have lost contact with each other.
Indoor/outdoor communication protection. Manual's own first step is a 1-minute power-off reset before any wiring checks.		 🟢 Switch the system off at the isolator, wait 20 to 30 minutes, then switch it back on, communication faults often clear after a power interruption. If the code returns, book a service.
E2 The control board can't detect the mains zero-crossing signal, a board-level fault.
Zero-crossing signal error. Manual states this indicates a faulty main control board.		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.
E3 The indoor fan isn't spinning at the speed it's being asked to.
Indoor fan speed out of control		 🟡 Book a service. It's safe to try one power-cycle at the isolator first.
E5 Either the outdoor temperature sensor circuit is open or shorted, or the outdoor unit's control board memory has a fault.
Outdoor temperature sensor open/short OR outdoor unit EEPROM parameter error (broader than E5 on the N series)		 🟡 Book a service, this needs a technician to test the sensor and outdoor board.
E6 The room or indoor-coil temperature sensor circuit is open or shorted.
Room or evaporator coil temperature sensor open/short circuit		 🟡 Book a service, a sensor fault needs a technician.
E7 The outdoor fan isn't spinning at the speed it's being asked to.
Outdoor fan speed out of control (N series wording for E7 is "outdoor unit fan protection")		 🟡 Check nothing is blocking or tangled in the outdoor unit (from the outside only), then book a service.
P0 The inverter power module has shut down because of an electrical fault or excessive current.
IPM malfunction or IGBT over-current protection (source misprints IPM as "IBM")		 🔴 Switch the system off at the isolator and call us, don't keep restarting it.
P1 The unit has shut down because the power supply voltage is too high or too low.
Over-voltage or under-voltage protection		 🟡 Switch off at the isolator for 20 to 30 minutes and try again, voltage dips after grid events can trip this. If it keeps happening, book a service.
P2 The top of the compressor has overheated and the unit has shut down to protect it.
Compressor top temperature protection. Manual's diagnosis path includes refrigerant charge and circuit blockage checks.		 🔴 Switch the system off at the isolator and call us, overheating can point to a refrigerant or compressor problem.
P4 The electronics that drive the inverter compressor have reported a fault.
Inverter compressor drive error. E4 and P3 are reserved (unused) on this series.		 🔴 Switch the system off at the isolator and call us, repeated restarts can stress the compressor.

Code still showing after a reset? Mention the code and your system type when you book and our office can line up the right technician and likely parts before we arrive.

Book a service  or call (02) 4760 0100 (24-hour line, Penrith & Blue Mountains).

Codes vary between models and generations, and manufacturers revise them. This guide is compiled from official service documentation and checked by Ample Air, but it is general information, not a diagnosis. Refrigerant and electrical work must be carried out by licensed technicians. Ample Air, ARC licences AU12976 & AU15788. Last verified August 2026.

Fujitsu fault codes & lamp flash patterns

by | Aug 3, 2026

When your Fujitsu system stops and shows a code, that code is the system telling you roughly where the problem is. Roughly is the key word. A fault code points in a direction, it rarely names the exact fix. Find your system below, tap your code, and it will take you straight to what it means and what to do.

Before you try anything: the only DIY steps that are ever safe are switching the system off at the isolator (and waiting 20 to 30 minutes), cleaning or checking filters, checking the controller settings and batteries, and keeping the outdoor unit clear. Anything behind a panel, anything electrical, and anything involving refrigerant or gas is licensed work. If a code below says switch off and call, please take it at its word.

How to read the tables: 🟢 means there is a safe first step worth trying. 🟡 means book a service, the system needs a technician. 🔴 means switch the system off at the isolator and call us on (02) 4760 0100.

Systems with the Fujitsu hardwired (wired) remote controller – older ducted and commercial splits

Where the code shows: Wired remote controller LCD. The controller first shows EE:EE; hold the Energy Save and Zone Control buttons together for more than 3 seconds to reveal the underlying code (same button combo returns it to normal)..

Tap your code: E0:00E1:00E2:00E3:00E4:00E5:00E6:00E7:00EA:00Eb:00Ec:00Ed:00EE:00EF:00
Code What it means What to do
E0:00 The indoor unit and the wall controller have stopped talking to each other.
Communications error, indoor unit to remote controller.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
E1:00 The indoor and outdoor units have stopped talking to each other.
Communications error, indoor unit to outdoor unit.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
E2:00 The sensor that reads the air returning to the indoor unit has failed (open circuit).
Return air thermistor open circuit.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E3:00 The sensor that reads the air returning to the indoor unit has failed (short circuit).
Return air thermistor short circuit.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E4:00 The indoor coil's temperature sensor has failed (open circuit).
Indoor coil thermistor open circuit.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E5:00 The indoor coil's temperature sensor has failed (short circuit).
Indoor coil thermistor short circuit.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E6:00 The outdoor coil's temperature sensor has failed (open circuit).
Outdoor coil thermistor open circuit.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E7:00 The outdoor coil's temperature sensor has failed (short circuit).
Outdoor coil thermistor short circuit.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
EA:00 The sensor that reads the outside air temperature has failed (open circuit).
Outdoor ambient thermistor open circuit.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
Eb:00 The sensor that reads the outside air temperature has failed (short circuit).
Outdoor ambient thermistor short circuit.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
Ec:00 The sensor on the compressor's discharge pipe has failed (open circuit).
Discharge pipe thermistor open circuit.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
Ed:00 The sensor on the compressor's discharge pipe has failed (short circuit).
Discharge pipe thermistor short circuit.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
EE:00 Refrigerant pressure in the system has gone too high and the unit has protected itself.
High pressure problem.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
EF:00 The compressor's discharge pipe is running too hot, which usually points to the system being short of refrigerant gas.
Discharge pipe temperature too high; source doc notes this typically means short of gas.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.

Fujitsu VRF (V-II series compendium; Airstage family) – indoor unit faults

Where the code shows: Two-character code on the simple/wired remote controller (also shown on group/central/touch-panel controllers); indoor unit signals the same fault with Operation/Timer LED flash counts plus continuous Filter LED flashing; outdoor unit 7-segment display shows E.5U.1 for any indoor fault..

Tap your code: 1214163132414251539U
Code What it means What to do
12 The indoor unit has lost contact with its wired remote controller.
Remote controller communication error (also raised if the indoor controller PCB's communication circuit fails). Indoor LEDs: Operation 1 flash / Timer 2 flashes.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
14 The indoor unit has dropped off the system's communication network – it hasn't heard from the outdoor unit for over 90 seconds.
Network communication error. Indoor LEDs: Operation 1 flash / Timer 4 flashes (list) – detailed section shows 1/6.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
16 Indoor units wired together in a group have stopped talking to each other.
Indoor unit parallel communication error. Indoor LEDs: Operation 1 flash / Timer 6 flashes.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
31 The indoor unit is unhappy with the frequency of its incoming power supply.
Indoor unit power frequency abnormal. Indoor LEDs: Operation 3 flashes / Timer 1 flash.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
32 The indoor unit's main circuit board has an internal fault (its stored settings can't be read properly).
Indoor unit main PCB error – model information error or EEPROM access abnormal. Indoor LEDs: Operation 3 flashes / Timer 2 flashes.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
41 The sensor that reads the room temperature has failed.
Room temperature sensor error. Indoor LEDs: Operation 4 flashes / Timer 1 flash.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
42 A temperature sensor on the indoor unit's coil has failed.
Indoor heat exchanger sensor error – inlet or outlet thermistor open/shorted. Indoor LEDs: Operation 4 flashes / Timer 2 flashes.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
51 The indoor unit's fan motor isn't spinning the way the controller expects.
Indoor unit fan motor error – feedback speed at zero or stuck at 1/3 of target for over a minute. Indoor LEDs: Operation 5 flashes / Timer 1 flash.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
53 The unit has detected a problem draining away condensate water.
Water drain abnormal (float switch tripped). Indoor LEDs: Operation 5 flashes / Timer 3 flashes.		 🟡 Switch the unit off to stop more condensate being produced and book a service. If you can see water dripping from the unit or ceiling, leave it off.
9U The fault is on the outdoor unit side – the outdoor unit will show a more specific code.
Outdoor unit error; check the outdoor unit's display code. Indoor LEDs: Operation 9 flashes / Timer 15 flashes.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.

Fujitsu VRF (V-II series compendium; Airstage family) – outdoor unit faults

Where the code shows: Outdoor unit 7-segment display shows the full E.XX.Y code (via MODE/EXIT/SELECT/ENTER buttons on the outdoor PCB); remote and central controllers show the two-character short form; indoor units show Operation 9 flashes / Timer 15 flashes for outdoor faults..

Tap your code: —-E13.1E14.1E14.2E14.5E28.1E28.4E61.5E62.3E62.6E62.8E63.1E67.2E68.1E68.2E69.1E71.1E71.2E72.1E72.2E73.3E74.1E75.1E77.1E82.1E82.2E83.1E83.2E84.1E86.1E86.3E86.4E86.5E92.1E92.2E93.1E94.1E95.5E97.1E97.4E97.5E9U.2E5U.1EA1.1EA2.1EA3.1EA3.2EA4.1EA4.2EA4.3EA5.1EAC.4
Code What it means What to do
—- The outdoor unit hasn't finished its initial setup and has no valid settings to run with.
Initial setting error; outdoor display stays blank/dashes, no code reaches the indoor units.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E13.1 In a multi-outdoor-unit system, the outdoor units have stopped talking to each other.
Communication error between outdoor units; remote shows 13.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
E14.1 The outdoor unit has lost network contact with an indoor unit it previously knew about (silent for 180+ seconds).
Outdoor unit network communication 1 error; remote shows 14.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
E14.2 The outdoor unit's network communication has failed at the communication board.
Outdoor unit network communication 2 error; remote shows 14.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
E14.5 The system found fewer indoor units on the network than it expects.
Indoor unit number shortage error; no code shown on indoor side.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E28.1 Automatic address setup failed – the outdoor unit couldn't assign addresses to the connected indoor units.
Auto address setting error; remote shows 28.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E28.4 Automatic address setup failed at a signal amplifier on the communication line.
Signal amplifier auto address setting error; remote shows 28.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E61.5 The three-phase power feeding the outdoor unit is wired in the wrong order, or one phase is missing.
Outdoor unit reverse phase / missing phase wire error; remote shows 61.		 🟡 Book a service – this is a power supply wiring issue that needs an electrician or technician. If the fault appeared right after site electrical work or a blackout, mention that when you call.
E62.3 The outdoor unit's circuit board can't read its own stored settings.
Outdoor unit EEPROM access error; remote shows 62.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E62.6 Two circuit boards inside the outdoor unit (main board and inverter) have stopped talking to each other.
Inverter communication error; remote shows 62.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E62.8 The settings stored on the outdoor unit's circuit board have become corrupted.
Outdoor unit EEPROM data error; remote shows 62.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E63.1 The inverter that drives the compressor has reported a fault.
Inverter error; remote shows 63.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E67.2 The inverter board detected a momentary dip or dropout in the power supply.
Inverter PCB momentary power failure detection; remote shows 67.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
E68.1 A power relay inside the outdoor unit isn't switching properly.
Magnetic relay error; remote shows 68.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E68.2 A protective resistor that softens the power-on surge is overheating, and the unit has shut down to protect itself.
Rush current limiting resistor temperature rise protection; remote shows 68.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
E69.1 The outdoor unit's communication board and main board have stopped talking to each other.
Outdoor unit communication PCB parallel communication error; remote shows 69.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E71.1 A sensor on the compressor's discharge pipe (circuit 1) has failed.
Discharge temperature sensor 1 error; remote shows 71.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E71.2 A sensor on the compressor's discharge pipe (circuit 2) has failed.
Discharge temperature sensor 2 error; remote shows 71.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E72.1 The temperature sensor on compressor 1 has failed.
Compressor temperature sensor 1 error; remote shows 72.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E72.2 The temperature sensor on compressor 2 has failed.
Compressor temperature sensor 2 error; remote shows 72.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E73.3 A temperature sensor on the outdoor coil's liquid line has failed.
Outdoor unit heat exchanger liquid temperature sensor error; remote shows 73.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E74.1 The sensor that reads the outside air temperature has failed.
Outdoor temperature sensor open or shorted; remote shows 74.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E75.1 The temperature sensor on the compressor's suction line has failed.
Suction gas temperature sensor error; remote shows 75.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E77.1 The temperature sensor on the inverter's heat sink has failed.
Heat sink temperature sensor error; remote shows 77.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E82.1 A temperature sensor at the sub-cooling heat exchanger's gas inlet has failed.
Sub-cool heat exchanger gas inlet temperature sensor error; remote shows 82.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E82.2 A temperature sensor at the sub-cooling heat exchanger's gas outlet has failed.
Sub-cool heat exchanger gas outlet temperature sensor error; remote shows 82.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E83.1 Liquid pipe temperature sensor 1 has failed.
Liquid pipe temperature sensor 1 error; remote shows 83.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E83.2 Liquid pipe temperature sensor 2 has failed.
Liquid pipe temperature sensor 2 error; remote shows 83.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E84.1 The sensor that measures compressor current has failed.
Current sensor 1 error; remote shows 84.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E86.1 The sensor that measures discharge (high side) refrigerant pressure has failed.
Discharge pressure sensor error; remote shows 86.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E86.3 The sensor that measures suction (low side) refrigerant pressure has failed.
Suction pressure sensor error; remote shows 86.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E86.4 High pressure safety switch 1 has tripped or failed.
High pressure switch 1 error; remote shows 86.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
E86.5 High pressure safety switch 2 has tripped or failed.
High pressure switch 2 error; remote shows 86.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
E92.1 Compressor 2 (the fixed-speed compressor) has a fault.
Compressor 2 error, detected via its current sensor; remote shows 92.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
E92.2 Compressor 2 is drawing an abnormal amount of current.
Compressor 2 current value error; remote shows 92.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
E93.1 The inverter compressor tried to start and couldn't.
Inverter compressor start-up error; remote shows 93.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
E94.1 The compressor drive tripped on a sudden over-current.
Trip detection; remote shows 94.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
E95.5 The compressor motor lost sync with its drive and stopped.
Compressor motor loss of synchronization; remote shows 95.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
E97.1 The outdoor unit's fan motor has jammed or isn't turning.
Outdoor unit fan motor lock error; remote shows 97.		 🟡 Make sure nothing is jammed in or leaning against the outdoor unit and that leaves or debris aren't blocking the fan, then try a power-cycle at the isolator. If the code returns, book a service.
E97.4 The outdoor fan motor's supply voltage has dropped too low.
Outdoor unit fan motor undervoltage; remote shows 97.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E97.5 The outdoor unit's fan motor is running too hot.
Outdoor unit fan motor temperature abnormal; remote shows 97.		 🟡 Check that the outdoor unit has clear space around it and nothing is blocking airflow, then book a service if the code returns after a power-cycle.
E9U.2 In a multi-outdoor-unit system, one of the secondary (slave) outdoor units has reported a fault.
Slave unit error; remote shows 9U.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E5U.1 One of the indoor units has a fault – the indoor unit or its controller will show the specific code.
Indoor unit error shown on the outdoor unit's display; press ENTER (long) on the outdoor PCB to see which indoor address.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
EA1.1 Compressor circuit 1 is discharging refrigerant at a dangerously high temperature – often a sign the system is short of refrigerant.
Discharge temperature 1 abnormal; remote shows A1.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
EA2.1 Compressor circuit 2 is discharging refrigerant at a dangerously high temperature – often a sign the system is short of refrigerant.
Discharge temperature 2 abnormal; remote shows A2.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
EA3.1 Compressor 1 itself is running too hot.
Compressor 1 temperature abnormal; remote shows A3.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
EA3.2 Compressor 2 itself is running too hot.
Compressor 2 temperature abnormal; remote shows A3.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
EA4.1 Refrigerant pressure on the high side has gone beyond safe limits.
High pressure abnormal; remote shows A4.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
EA4.2 The unit has shut down to protect itself from high refrigerant pressure (protection stage 1).
High pressure protection 1; remote shows A4.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
EA4.3 The unit has shut down to protect itself from high refrigerant pressure (protection stage 2).
High pressure protection 2; remote shows A4.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
EA5.1 Refrigerant pressure on the low side has dropped too far – commonly a sign of refrigerant loss.
Low pressure abnormal; remote shows A5.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
EAC.4 The inverter's heat sink is running too hot – often an airflow or cooling problem at the outdoor unit.
Heat sink temperature abnormal; remote shows AC.		 🟡 Check the outdoor unit has clear space around it and its coil isn't clogged with leaves or debris, then book a service – the electronics are overheating.

Lifestyle inverter wall-mounted range (ASTG-LVCA / ASTG-LFCA and related, approx. 2010s onward)

Where the code shows: Indoor unit lamps: the Operation lamp flashes X times, then the Timer lamp flashes Y times, repeating in a cycle while the Economy lamp flashes continuously. Codes below are written as Operation flashes / Timer flashes. Systems fitted with a wired remote controller also show a matching two-digit code after 'Er' (Operation count = first digit, Timer count = second digit; 10 flashes displays as the letter A)..

Tap your code: 1/11/21/52/12/22/32/43/13/23/53/94/14/25/15/35/95/156/26/36/46/56/107/17/27/37/47/57/67/78/28/38/48/69/49/59/79/89/910/110/310/513/2
Code What it means What to do
1/1 The indoor and outdoor units have stopped talking to each other.
Serial communication error. Wired remote shows 11.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
1/2 The indoor unit has lost contact with its wired remote controller (where one is fitted).
Wired remote controller communication error. Wired remote shows 12.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
1/5 The installer's commissioning test run was never completed on this system.
Check run unfinished.		 🟡 Book a service or call your installer – the system needs its commissioning run completed by a technician.
2/1 The pipework and cabling between the indoor and outdoor units don't match what the system expects.
Number of wires and pipes error – connection configuration fault.		 🟡 Book a service – this points to how the system was configured rather than anything you can fix from the controls. If the system was recently installed, call the installer.
2/2 The indoor unit's capacity doesn't match what the outdoor unit expects.
Indoor unit capacity error. Wired remote shows 22.		 🟡 Book a service – this points to how the system was configured rather than anything you can fix from the controls. If the system was recently installed, call the installer.
2/3 The indoor and outdoor units are a combination the system doesn't recognise as valid.
Connected combination error.		 🟡 Book a service – this points to how the system was configured rather than anything you can fix from the controls. If the system was recently installed, call the installer.
2/4 The system found a different number of indoor units or branch boxes than it expects.
Number of indoor units / number of branch boxes error (multi and branch-box configurations).		 🟡 Book a service – this points to how the system was configured rather than anything you can fix from the controls. If the system was recently installed, call the installer.
3/1 The unit detected an interruption to its power supply.
Power supply interruption error. Wired remote shows 31. Listed on the ASTG34LFCA page.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – this fault is often left over from a blackout or brownout. If the code comes back, book a service.
3/2 The indoor unit's main circuit board has an internal fault (its stored settings can't be read properly).
Indoor unit model information error / EEPROM access abnormal.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
3/5 The manual start button on the indoor unit itself is stuck or its circuit has failed.
Manual auto switch error. Wired remote shows 35.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
3/9 The circuit that drives the indoor fan motor has failed.
Fan motor driving circuit error. Wired remote shows 39. Listed on the ASTG34LFCA page.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
4/1 The sensor that reads the room temperature has failed.
Indoor room thermistor (inlet air temperature sensor) error. Wired remote shows 41.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
4/2 A temperature sensor on the indoor unit's coil has failed.
Indoor heat exchanger (middle) thermistor error. Wired remote shows 42.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
5/1 The indoor unit's fan motor isn't running the way the controller expects.
Indoor unit fan motor (1) error. Wired remote shows 51.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
5/3 The unit has detected a problem draining away condensate water.
Drainage error. Wired remote shows 53. Corroborated by airturners.com.au Fujitsu error code guide.		 🟡 Switch the unit off to stop more condensate being produced and book a service. If you can see water dripping from the unit or down the wall, leave it off.
5/9 The indoor unit's second fan motor isn't running properly (models with two fans).
Indoor unit fan motor 2 error. Wired remote shows 59. Listed on the ASTG34LFCA page.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
5/15 The indoor unit has reported a general fault without a more specific code.
Indoor unit error. Wired remote shows 5U. Listed on the ASTG34LFCA page.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
6/2 The outdoor unit's circuit board can't read its own stored model settings.
Outdoor unit model information error. Wired remote shows 62.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
6/3 The inverter that drives the compressor has reported a fault.
Inverter error. Wired remote shows 63. Corroborated by airturners.com.au Fujitsu error code guide.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
6/4 A power-conditioning circuit in the outdoor unit (active filter) has a voltage problem.
Active filter error / A.F. voltage error.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
6/5 The power module that drives the compressor has reported a fault.
IPM (intelligent power module) error. Wired remote shows 65.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
6/10 The indoor unit's display board and main board have stopped talking to each other.
Display PCB communication error.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
7/1 The sensor on the compressor's discharge pipe has failed.
Discharge thermistor error. Wired remote shows 71.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
7/2 The temperature sensor on the compressor body has failed.
Compressor thermistor error. Wired remote shows 72.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
7/3 A temperature sensor on the outdoor coil's liquid line has failed.
Heat exchanger liquid outlet thermistor error. Wired remote shows 73 (the ASTG34LFCA page labels 73 as heat exchanger centre / liquid outlet temperature sensor error).		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
7/4 The sensor that reads the outside air temperature has failed.
Outdoor thermistor error. Wired remote shows 74.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
7/5 The temperature sensor on the compressor's suction line has failed.
Suction gas thermistor error.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
7/6 A temperature sensor on one of the outdoor unit's valves has failed.
Valve thermistor error.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
7/7 The temperature sensor on the inverter's heat sink has failed.
Heat sink thermistor error. Wired remote shows 77.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
8/2 A temperature sensor at the sub-cooling heat exchanger has failed.
Sub-cool heat exchanger gas inlet / gas outlet thermistor error.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
8/3 A temperature sensor on the liquid refrigerant pipe has failed.
Liquid pipe thermistor error.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
8/4 The sensor that measures compressor current has failed.
Current sensor error. Wired remote shows 84.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
8/6 A refrigerant pressure sensor has failed or the high pressure safety switch has tripped.
Discharge pressure sensor / suction pressure sensor / high pressure switch error. Wired remote shows 86. The source table bundles sensor and safety-switch faults into one code, so the safer red lane is used.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
9/4 The compressor drive tripped on a sudden over-current.
Over current error. Wired remote shows 94. Corroborated by airturners.com.au Fujitsu error code guide.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
9/5 The outdoor unit can't control the compressor properly.
Compressor control error. Wired remote shows 95.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
9/7 The outdoor unit's fan motor isn't running the way the controller expects.
Outdoor unit fan motor (1) error. Wired remote shows 97.		 🟡 Make sure nothing is jammed in or leaning against the outdoor unit and that leaves or debris aren't blocking the fan, then try a power-cycle at the isolator. If the code returns, book a service.
9/8 The outdoor unit's second fan motor isn't running properly (models with two fans).
Outdoor unit fan motor 2 error. Wired remote shows 98. Listed on the ASTG34LFCA page.		 🟡 Make sure nothing is jammed in or leaning against the outdoor unit and that leaves or debris aren't blocking the fan, then try a power-cycle at the isolator. If the code returns, book a service.
9/9 The valve that switches the system between heating and cooling has a fault.
4-way (reversing) valve error. Wired remote shows 99.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
10/1 The compressor is discharging refrigerant at a dangerously high temperature – often a sign the system is short of refrigerant.
Discharge temperature error. Wired remote shows A1.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
10/3 The compressor itself is running too hot.
Compressor temperature error. Wired remote shows A3.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
10/5 Refrigerant pressure on the low side has dropped too far – commonly a sign of refrigerant loss.
Low pressure error. Wired remote shows A5.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
13/2 A branch box connecting multiple indoor units has a fault (branch-box multi systems only).
Branch boxes error.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.

Classic inverter wall-mounted splits (ASTA-JCC / ASTA-LCC era, mid-2000s)

Where the code shows: Indoor unit lamps: the Operation LED flash count gives the fault family and the Timer LED flash count gives the specific fault, written below as Operation flashes / Timer flashes. For serial signal errors ('-' rows) the Operation LED is not flash-counting – it stays in its normal state (ASTA-JCC) or off (ASTA-LCC) while only the Timer LED flashes..

Tap your code: -/2-/3-/4-/52/22/33/23/33/44/24/34/44/74/85/25/35/55/66/26/37/27/38/4ALL BLINK
Code What it means What to do
-/2 The indoor and outdoor units failed to establish contact when the system tried to start.
Serial signal (reverse) error immediately after start of operation.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
-/3 The indoor and outdoor units lost contact while the system was running.
Serial signal (reverse) error during operation.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
-/4 The outdoor unit failed to hear from the indoor unit when the system tried to start.
Serial signal (forward) error immediately after start of operation.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
-/5 The outdoor unit stopped hearing from the indoor unit while the system was running.
Serial signal (forward) error during operation.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
2/2 The sensor that reads the room temperature has failed (open or short circuit).
Indoor temperature thermistor open / short. Corroborated by airturners.com.au Fujitsu error code guide.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
2/3 A temperature sensor on the indoor unit's coil has failed (open or short circuit).
Heat exchanger middle thermistor open / short. Corroborated by airturners.com.au Fujitsu error code guide.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
3/2 The sensor on the compressor's discharge pipe has failed (open or short circuit).
Discharge thermistor open / short.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
3/3 The outdoor coil's temperature sensor has failed (open circuit).
Outdoor heat exchanger thermistor open.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
3/4 The sensor that reads the outside air temperature has failed (open or short circuit).
Outdoor temperature thermistor open / short.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
4/2 The manual start button's circuit on the indoor unit has jammed closed.
Forced automatic switch welded.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
4/3 The main power relay inside the indoor unit has stuck closed.
Main relay welded.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
4/4 The unit detected an interruption to its power supply.
Power interruption error.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – this fault is often left over from a blackout or brownout. If the code comes back, book a service.
4/7 An internal power-supply protection on the indoor board has shut the unit down.
VDD permanent stop protection. The ASTA07/09JCC page prints a '?' beside this row; the ASTA09LCC page lists it cleanly.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
4/8 An internal power-supply protection on the indoor board has shut the unit down (reverse VDD).
Reverse VDD permanent stop protection. Listed for ASTA09LCC only.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
5/2 The outdoor unit tripped on a sudden over-current.
Current trip error.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
5/3 The outdoor unit's current-measuring circuit isn't reading properly.
CT (current transformer) abnormal.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
5/5 The compressor drive can't detect the compressor motor's position.
Compressor location detection error.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
5/6 The circuit that drives the outdoor fan motor has a fault.
Outdoor unit fan drive system abnormal.		 🟡 Make sure nothing is jammed in or leaning against the outdoor unit and that leaves or debris aren't blocking the fan, then try a power-cycle at the isolator. If the code returns, book a service.
6/2 The indoor unit's fan motor has jammed or isn't turning.
Indoor fan motor abnormal lock.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
6/3 The indoor unit's fan motor isn't spinning at the speed the controller expects.
Indoor fan motor abnormal rotation.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
7/2 The compressor's discharge pipe is running too hot, which usually points to the system being short of refrigerant gas.
Discharge temperature abnormal.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
7/3 Refrigerant pressure has risen too high while cooling and the unit has protected itself.
Cooling high pressure abnormal rise.		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
8/4 A power-conditioning circuit in the outdoor unit has failed.
PFC (power factor correction) circuit error.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.

Early non-inverter wall-mounted splits (AST-PSA series, late 1990s-2000s)

Where the code shows: Indoor unit lamps: the Operation lamp (red) flashes slowly a set number of times (0.5 sec flashes, then a 5 sec pause) while the Timer lamp flickers rapidly (0.1 sec on/off). For serial faults the Operation lamp stays on while the Timer lamp blinks steadily. A second display mode (Operation flickering rapidly, Timer flashing in 0.5 sec counts) gives the technician sub-code..

Tap your code: ON + Timer flashing2 flashes3 flashes4 flashes5 flashes6 flashes7 flashes8 flashesBoth lamps flash together
Code What it means What to do
ON + Timer flashing The indoor and outdoor units have stopped talking to each other.
Serial signal abnormal (indoor unit to outdoor unit). Operation lamp stays on, Timer lamp blinks steadily (0.5 sec on/off).		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
2 flashes A temperature sensor in the indoor unit (room or pipe sensor) has failed.
Indoor thermistor abnormal – piping or room temperature thermistor, open or short.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
3 flashes A temperature sensor on the outdoor unit has failed.
Outdoor unit thermistor abnormal – discharge, heat exchange or outside air temperature thermistor.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
4 flashes The indoor unit's electronics have a fault.
Indoor unit control unit parts abnormal (sub-codes cover manual auto switch fused, main relay fused, power interrupt faulty).		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
5 flashes The outdoor unit's electronics have a fault.
Outdoor unit control unit parts abnormal (sub-codes cover current trip and CT abnormal).		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
6 flashes The indoor unit's fan motor has jammed or isn't running at the right speed.
Indoor fan motor abnormal – locked, speed abnormal, starting failure, overcurrent or supply voltage abnormal.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
7 flashes Something is wrong in the refrigerant circuit – the compressor is running too hot, which usually points to the system being short of gas.
Refrigerant cycle abnormal (discharge temperature abnormal: insufficient gas etc.; sub-codes cover cooling pressure over-rise, intake blocking and heating fan stop protection).		 🔴 Switch the system off at the isolator and call us. Keeping it running with this fault risks further damage.
8 flashes A power-conditioning circuit in the unit has failed.
Active filter abnormal – parts abnormal, voltage feedback connector pulled etc. Listed for AST13PSA-W.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
Both lamps flash together Both lamps flashing together once a second is the test-operation display, not a fault.
Test operation display (Operation and Timer lamps flash simultaneously, 1.0 sec on/off).		 🟢 Nothing is wrong if a technician is testing the unit. If this shows in normal use, power-cycle at the isolator (off, wait 20-30 minutes, back on) and book a service if it won't clear.

J Series multi-split indoor units (wall-mounted heads on J Series multi outdoor units)

Where the code shows: E:XX code on the wired or simple remote controller (where fitted); the indoor unit signals the same fault with flash combinations of the Operation, Timer and third (Swing) indicators – rapid flicker means 0.1 sec on/off. Outdoor unit faults also show on LEDs on the outdoor PCB (technician access only, not extracted)..

Tap your code: E:02E:03E:04E:06E:07E:09E:0AE:0bE:11E:13E:18E:1FE:21E:32
Code What it means What to do
E:02 The indoor unit's circuit board doesn't recognise its own model settings.
Model information abnormal. Indoor lamps: Operation and Timer flicker rapidly (0.1 sec on/off).		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E:03 The indoor unit's main processor has an internal fault.
Microcomputer error. Indoor lamps: Operation 5 flashes / Timer rapid flicker / third lamp 2 flashes.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E:04 The incoming mains power frequency is outside what the unit expects.
Power supply frequency abnormal. Indoor lamps: Operation, Timer and third lamp all flicker rapidly.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E:06 The indoor unit's circuit board can't read its own stored settings.
EEPROM access error. Indoor lamps: Operation rapid flicker / Timer 4 flashes / third lamp 1 flash.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E:07 The settings stored on the indoor unit's circuit board have been corrupted or erased.
EEPROM deletion error. Indoor lamps: Operation rapid flicker / Timer 4 flashes / third lamp 2 flashes.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E:09 The sensor that reads the room temperature has failed.
Room temperature thermistor error. Indoor lamps: Operation 2 flashes / Timer rapid flicker.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E:0A A temperature sensor on the indoor unit's coil (middle) has failed.
Indoor unit heat exchanger thermistor (middle) error. Indoor lamps: Operation 3 flashes / Timer rapid flicker / third lamp 2 flashes.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E:0b A temperature sensor on the indoor unit's coil (inlet) has failed.
Indoor unit heat exchanger thermistor (inlet) error. Indoor lamps: Operation 3 flashes / Timer rapid flicker / third lamp 1 flash.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E:11 The unit has detected a problem draining away condensate water.
Drain abnormal. Indoor lamps: Operation 4 flashes / Timer rapid flicker.		 🟡 Switch the unit off to stop more condensate being produced and book a service. If you can see water dripping from the unit or down the wall, leave it off.
E:13 The indoor unit's fan isn't running the way the controller expects.
Indoor unit fan error. Indoor lamps: Operation 6 flashes / Timer rapid flicker.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.
E:18 The indoor unit has lost contact with its wired or simple remote controller.
Communication error 1 or 2 (indoor unit to wired/simple remote controller). Indoor lamps: Operation 5 flashes / Timer rapid flicker / third lamp 1 flash (error 1) or 4 flashes (error 2).		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
E:1F Signals between the system's circuit boards aren't getting through.
Transmission error. Indoor lamps: Operation rapid flicker / Timer 5 flashes / third lamp 1 flash.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
E:21 Indoor units wired together have stopped talking to each other.
Parallel communication error. Indoor lamps: Operation rapid flicker / Timer 6 flashes.		 🟢 Turn the system off at the electrical isolator, wait 20-30 minutes, then turn it back on – communication errors like this often clear after a power interruption. If the code comes back, book a service.
E:32 The fault is on the outdoor unit side.
Outdoor unit error. Indoor lamps: Operation rapid flicker / Timer 3 flashes / third lamp 3 flashes.		 🟡 Try a power-cycle at the isolator (off, wait 20-30 minutes, back on). If the code returns, book a service – this one needs a technician.

Code still showing after a reset? Mention the code and your system type when you book and our office can line up the right technician and likely parts before we arrive.

Book a service  or call (02) 4760 0100 (24-hour line, Penrith & Blue Mountains).

Codes vary between models and generations, and manufacturers revise them. This guide is compiled from official service documentation and checked by Ample Air, but it is general information, not a diagnosis. Refrigerant and electrical work must be carried out by licensed technicians. Ample Air, ARC licences AU12976 & AU15788. Last verified August 2026.

Haier air conditioner fault codes

by | Aug 3, 2026

When your Haier system stops and shows a code, that code is the system telling you roughly where the problem is. Roughly is the key word. A fault code points in a direction, it rarely names the exact fix. Find your system below, tap your code, and it will take you straight to what it means and what to do.

Before you try anything: the only DIY steps that are ever safe are switching the system off at the isolator (and waiting 20 to 30 minutes), cleaning or checking filters, checking the controller settings and batteries, and keeping the outdoor unit clear. Anything behind a panel, anything electrical, and anything involving refrigerant or gas is licensed work. If a code below says switch off and call, please take it at its word.

How to read the tables: 🟢 means there is a safe first step worth trying. 🟡 means book a service, the system needs a technician. 🔴 means switch the system off at the isolator and call us on (02) 4760 0100.

HEK & N series wall splits

Where the code shows: E-codes on the indoor display panel; outdoor faults also shown as LED1 flash counts on the outdoor PCB..

Tap your code: E7E1E2E4E14F12F1F22F3F19F4F8F21F7F6F25F11F28F2F23E9
Code What it means What to do
E7 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication fault. Indoor display shows E7; outdoor LED1 flashes 15 times. Haier's E7 guide has the technician check the interconnect cable, active/neutral wiring and the comms wire; if the unit runs about 4 minutes before faulting it points to the indoor PCB; with outdoor LED2 on the cause is the outdoor or indoor PCB, with LED2 off the outdoor PCB or power module.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E1 The indoor unit's room temperature sensor isn't reading properly.
Room temperature sensor failure.		 🟡 Book a service call – this one needs a technician.
E2 The indoor coil's temperature sensor isn't reading properly.
Heat-exchange sensor failure.		 🟡 Book a service call – this one needs a technician.
E4 The indoor unit's control board has a memory fault.
Indoor EEPROM error.		 🟡 Book a service call – this one needs a technician.
E14 The indoor fan motor isn't running properly.
Indoor fan motor malfunction.		 🟡 Book a service call – this one needs a technician.
F12 The outdoor unit's control board has a memory fault.
Outdoor EEPROM error. Outdoor LED1 flashes 1 time.		 🟡 Book a service call – this one needs a technician.
F1 The outdoor unit's inverter power module tripped to protect itself.
Power module (IPM) protection – over-current or short circuit. Outdoor LED1 flashes 2 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F22 The outdoor unit shut down because it drew too much electrical current.
AC over-current protection. Outdoor LED1 flashes 3 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F3 Two boards inside the outdoor unit (power module and main PCB) have lost communication.
Power module to outdoor PCB communication fault. Outdoor LED1 flashes 4 times.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
F19 The incoming power supply voltage is too high or too low.
Power voltage out of range. Outdoor LED1 flashes 6 times.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
F4 The compressor got too hot and the unit shut down to prevent damage.
Discharge temperature overheat protection – can point to low refrigerant. Outdoor LED1 flashes 8 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F8 The outdoor fan motor isn't running properly.
Outdoor DC fan motor fault. Outdoor LED1 flashes 9 times.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
F21 The outdoor defrost temperature sensor isn't reading properly.
Defrost temperature sensor failure. Outdoor LED1 flashes 10 times.		 🟡 Book a service call – this one needs a technician.
F7 The outdoor suction temperature sensor isn't reading properly.
Suction temperature sensor failure. Outdoor LED1 flashes 11 times.		 🟡 Book a service call – this one needs a technician.
F6 The outdoor air temperature sensor isn't reading properly.
Ambient temperature sensor failure. Outdoor LED1 flashes 12 times.		 🟡 Book a service call – this one needs a technician.
F25 The compressor discharge temperature sensor isn't reading properly.
Discharge temperature sensor failure. Outdoor LED1 flashes 13 times.		 🟡 Book a service call – this one needs a technician.
F11 The compressor isn't running the way the controller expects.
Compressor running abnormal / loss of synchronism. Outdoor LED1 flashes 18 times.		 🟡 Book a service call – this one needs a technician.
F28 The circuit that tracks the compressor's rotor position has a fault.
Compressor loss-of-synchronism / position detection error. Outdoor LED1 flashes 19 times.		 🟡 Book a service call – this one needs a technician.
F2 The compressor drew too much current and the unit shut down.
Compressor over-current. Outdoor LED1 flashes 24 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F23 The compressor drew too much current on one phase and the unit shut down.
Single-phase compressor over-current protection. Outdoor LED1 flashes 25 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E9 The indoor unit overheated while heating and shut down to protect itself.
Indoor overload in heating mode – restricted airflow is a common cause; parts list also mentions indoor pipe sensor and refrigerant. Outdoor LED1 flashes 21 times.		 🟡 Check the return-air filters are clean, then book a service if the code stays.

T series wall splits (LED flash patterns)

Where the code shows: Three indoor LEDs – Power/Timer/Operation (labelled Operation/Heat/Cool on some models) – read as pattern ON / FLASH / OFF in that order; outdoor faults also shown as LED1 flash counts on the outdoor PCB..

Tap your code: E1E2F21F25E9 / E5F6E7FLASH-OFF-ON (indoor LEDs)OFF-FLASH-OFF (indoor LEDs)F22FLASH-FLASH-ON (indoor LEDs)F1E9F24E4E14
Code What it means What to do
E1 The indoor unit's room temperature sensor isn't reading properly.
Indoor LEDs (Power/Timer/Operation): FLASH-OFF-OFF.		 🟡 Book a service call – this one needs a technician.
E2 The indoor pipe temperature sensor isn't reading properly.
Indoor LEDs: FLASH-ON-ON.		 🟡 Book a service call – this one needs a technician.
F21 The outdoor defrost temperature sensor isn't reading properly.
Indoor LEDs: ON-ON-FLASH. Outdoor LED1 flashes 10 times.		 🟡 Book a service call – this one needs a technician.
F25 The compressor discharge (exhaust) temperature sensor isn't reading properly.
Indoor LEDs: FLASH-ON-OFF. Outdoor LED1 flashes 13 times.		 🟡 Book a service call – this one needs a technician.
E9 / E5 The indoor unit shut down to protect itself – overheating in heating mode, or icing up in cooling mode.
Indoor heating overload or anti-freeze protection. Indoor LEDs: ON-OFF-FLASH. Outdoor LED1 flashes 20 or 21 times.		 🟡 Check the return-air filters are clean, then book a service if the code stays.
F6 The outdoor air temperature sensor isn't reading properly.
Indoor LEDs: ON-FLASH-OFF. Outdoor LED1 flashes 12 times.		 🟡 Book a service call – this one needs a technician.
E7 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication fault. Indoor display shows E7; outdoor LED1 flashes 15 times. Haier's E7 guide has the technician check the interconnect cable, active/neutral wiring and the comms wire; if the unit runs about 4 minutes before faulting it points to the indoor PCB; with outdoor LED2 on the cause is the outdoor or indoor PCB, with LED2 off the outdoor PCB or power module. Indoor LEDs: OFF-OFF-FLASH.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
FLASH-OFF-ON (indoor LEDs) The compressor isn't running the way the controller expects.
Compressor running abnormal – the table lists a blocked compressor or power module fault as causes; no display code is assigned.		 🟡 Book a service call – this one needs a technician.
OFF-FLASH-OFF (indoor LEDs) The outdoor unit has a fault – the outdoor unit's LED1 flash count identifies which one.
Grouped 'other error' display covering F12, F3, F27, F7, F11, F28, F43 and F4 (outdoor LED1 flashes 1, 4, 7, 11, 18, 19, 46 or 8 times).		 🟡 Book a service call – this one needs a technician.
F22 The unit shut down because it drew too much electrical current.
AC over-current protection. Indoor LEDs: FLASH-FLASH-OFF. Outdoor LED1 flashes 3 times. Causes listed: overcharged refrigerant, supply voltage under 187 V, power module or outdoor PCB fault.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
FLASH-FLASH-ON (indoor LEDs) The unit shut down on a DC over-current trip.
DC over-current protection – blocked compressor, power module fault, or supply voltage outside 187-242 V; no display code is assigned.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F1 The inverter power module overheated and the unit shut down to protect itself.
Power module overheat (IPM protection). Indoor LEDs: ON-FLASH-FLASH. Outdoor LED1 flashes 2 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E9 The indoor unit overheated while heating and shut down to protect itself.
Indoor overload in heating. Indoor LEDs: FLASH-FLASH-FLASH.		 🟡 Check the return-air filters are clean, then book a service if the code stays.
F24 The compressor is drawing abnormal running current.
Compressor running current abnormal. Indoor LEDs: FLASH-OFF-FLASH. Outdoor LED1 flashes 27 times. Causes listed: outdoor PCB fault, low refrigerant charge, four-way valve fault.		 🟡 Book a service call – this one needs a technician.
E4 The indoor unit's control board has a fault.
Indoor PCB fault. Indoor LEDs: FLASH-ON-FLASH.		 🟡 Book a service call – this one needs a technician.
E14 The indoor fan motor isn't running properly.
Indoor fan motor fault. Indoor LEDs: OFF-ON-FLASH.		 🟡 Book a service call – this one needs a technician.

DAC models – complete outdoor LED flash list (source header: 'not in any manual')

Where the code shows: Outdoor PCB LED flash counts; matching E/F code shows on indoor displays that have one..

Tap your code: F12F1F22F3F20F19F27F4F8F21F7F6F25F30E7F13F14F11F28F15E5F5F2F23F9F24F41F43E1E2E4E14
Code What it means What to do
F12 The outdoor unit's control board has a memory fault.
Outdoor EEPROM faulty. Outdoor LED flashes 1 time.		 🟡 Book a service call – this one needs a technician.
F1 The inverter power module tripped on over-current or a short circuit.
IPM over-current or short circuit. Outdoor LED flashes 2 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F22 The outdoor unit shut down because it drew too much electrical current.
AC over-current protection. Outdoor LED flashes 3 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F3 Two boards inside the outdoor unit (module and main PCB) have lost communication.
Module-to-outdoor-PCB communication failure. Outdoor LED flashes 4 times.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
F20 The compressor overloaded and the unit shut down to protect it.
Compressor overload. Outdoor LED flashes 5 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F19 The incoming power supply voltage is too high or too low.
Supply voltage out of range. Outdoor LED flashes 6 times.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
F27 The compressor has stalled or its current-monitoring circuit has failed.
Compressor current sampling circuit fault; compressor blocked or stopped. Outdoor LED flashes 7 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F4 The compressor got too hot and the unit shut down to prevent damage.
Discharge temperature overheating. Outdoor LED flashes 8 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F8 The outdoor fan motor isn't running properly.
DC fan motor malfunction. Outdoor LED flashes 9 times.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
F21 The outdoor defrost temperature sensor isn't reading properly.
Defrost sensor malfunction. Outdoor LED flashes 10 times.		 🟡 Book a service call – this one needs a technician.
F7 The compressor suction temperature sensor isn't reading properly.
Suction sensor malfunction. Outdoor LED flashes 11 times.		 🟡 Book a service call – this one needs a technician.
F6 The outdoor air temperature sensor isn't reading properly.
Ambient sensor malfunction. Outdoor LED flashes 12 times.		 🟡 Book a service call – this one needs a technician.
F25 The compressor discharge temperature sensor isn't reading properly.
Discharge sensor malfunction. Outdoor LED flashes 13 times.		 🟡 Book a service call – this one needs a technician.
F30 The outdoor suction temperature climbed too high.
Outdoor suction temp overtop. Outdoor LED flashes 14 times.		 🟡 Book a service call – this one needs a technician.
E7 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication fault. Indoor display shows E7; outdoor LED1 flashes 15 times. Haier's E7 guide has the technician check the interconnect cable, active/neutral wiring and the comms wire; if the unit runs about 4 minutes before faulting it points to the indoor PCB; with outdoor LED2 on the cause is the outdoor or indoor PCB, with LED2 off the outdoor PCB or power module.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
F13 The system is short of refrigerant, or refrigerant flow is blocked.
Lack of refrigerant or discharging fault. Outdoor LED flashes 16 times.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
F14 The valve that switches between heating and cooling failed to change over.
4-way valve switching failure. Outdoor LED flashes 17 times.		 🟡 Book a service call – this one needs a technician.
F11 The compressor isn't running the way the controller expects.
Loss of synchronism detection. Outdoor LED flashes 18 times.		 🟡 Book a service call – this one needs a technician.
F28 The circuit that tracks the compressor's rotor position has a fault.
Compressor position detection circuit fault. Outdoor LED flashes 19 times.		 🟡 Book a service call – this one needs a technician.
F15 The electrical terminal block is getting too hot.
Terminal block temperature too high – US-market models only. Outdoor LED flashes 20 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E5 The indoor coil started icing up and the unit shut down to protect itself.
Indoor anti-frosting protection. Outdoor LED flashes 22 times.		 🟡 Check the return-air filters are clean, then book a service if the code stays.
F5 The inverter power module overheated.
Module thermal overload. Outdoor LED flashes 23 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F2 The compressor failed to start, or drew too much current.
Compressor start failure / high compressor current. Outdoor LED flashes 24 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F23 The power module drew too much input current.
Module input over-current. Outdoor LED flashes 25 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F9 The power module reset itself – often after a power glitch.
Power module reset. Outdoor LED flashes 26 times.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
F24 The circuit that measures compressor current has a fault.
Current detect circuit malfunction – power module or compressor fault. Outdoor LED flashes 27 times.		 🟡 Book a service call – this one needs a technician.
F41 Refrigerant pressure climbed too high and the system shut down to protect itself.
System high-pressure protection – refrigerant overcharge, high condensing temperature or fan motor fault. Outdoor LED flashes 44 times. Some models don't have this fault.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F43 The indoor and outdoor units aren't a matching pairing.
Wrong match between indoor and outdoor unit. Outdoor LED flashes 46 times. Some models don't have this fault.		 🟡 Book a service call – this one needs a technician.
E1 The indoor unit's room temperature sensor isn't reading properly.
Room temperature sensor failure (no outdoor LED count).		 🟡 Book a service call – this one needs a technician.
E2 The indoor coil's temperature sensor isn't reading properly.
Indoor coil temperature sensor failure (no outdoor LED count).		 🟡 Book a service call – this one needs a technician.
E4 The indoor unit's control board has a fault.
Indoor PCB error (no outdoor LED count).		 🟡 Book a service call – this one needs a technician.
E14 The indoor fan motor isn't running properly.
Indoor fan motor malfunction (no outdoor LED count).		 🟡 Book a service call – this one needs a technician.

Multi slim & mid ducted indoor units (AD09-24SS1ERA(N)(P), AD12/18MS1ERA, AD24MS2ERA)

Where the code shows: Wired controller shows the code; indoor PCB LED4 (yellow) flashes the tens digit and LED3 (green) the units digit. For outdoor faults the flash count equals the outdoor error code plus 20..

Tap your code: 01020407080C0D0E
Code What it means What to do
01 The indoor unit's room temperature sensor isn't reading properly.
Indoor ambient temperature sensor malfunction – disconnected, broken, out of position or shorted.		 🟡 Book a service call – this one needs a technician.
02 The indoor pipe (coil) temperature sensor isn't reading properly.
Indoor piping temperature sensor malfunction.		 🟡 Book a service call – this one needs a technician.
04 The indoor unit's control board has a memory fault.
Indoor PCB EEPROM error.		 🟡 Book a service call – this one needs a technician.
07 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication abnormal – wiring, addressing, power supply or PCB.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
08 The wired controller has lost communication with the indoor unit.
Wired controller to indoor unit communication abnormal (no wired-controller display for this one).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0C The condensate drain system has a fault – pump or float switch.
Drain system malfunction (LED flash count 12).		 🟡 Book a service call – the drain needs attention before it can run safely.
0D The unit can't read the incoming mains power waveform properly.
Zero-cross signal detected wrong (LED flash count 13).		 🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0E The indoor fan motor isn't running properly.
Indoor DC fan motor abnormal (LED flash count 14).		 🟡 Book a service call – this one needs a technician.

Multi cassette indoor units (AB09/12/18CS2ERA)

Where the code shows: Wired controller shows the code; indoor PCB LED5 (red) flashes the tens digit and LED1 (yellow) the units digit. For outdoor faults the flash count equals the outdoor error code plus 20..

Tap your code: 01020407080C0D0E
Code What it means What to do
01 The indoor unit's room temperature sensor isn't reading properly.
Indoor ambient temperature sensor malfunction – disconnected, broken, out of position or shorted.		 🟡 Book a service call – this one needs a technician.
02 The indoor pipe (coil) temperature sensor isn't reading properly.
Indoor piping temperature sensor malfunction.		 🟡 Book a service call – this one needs a technician.
04 The indoor unit's control board has a memory fault.
Indoor PCB EEPROM error.		 🟡 Book a service call – this one needs a technician.
07 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication abnormal – wiring, addressing, power supply or PCB.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
08 The wired controller has lost communication with the indoor unit.
Wired controller to indoor unit communication abnormal (no wired-controller display for this one).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0C The condensate drain system has a fault – pump or float switch.
Drain system malfunction (LED flash count 12).		 🟡 Book a service call – the drain needs attention before it can run safely.
0D The unit can't read the incoming mains power waveform properly.
Zero-cross signal detected wrong (LED flash count 13).		 🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0E The indoor fan motor isn't running properly.
Indoor DC fan motor abnormal (LED flash count 14).		 🟡 Book a service call – this one needs a technician.

Multi cassette indoor unit (AB24ES1ERA(S))

Where the code shows: Wired controller shows the code (hex); indoor PCB LED4 (yellow) tens digit, LED3 (green) units digit. Wired-controller codes 15-40 (hex) mean an outdoor fault: convert the hex value to decimal and subtract 20 to get the outdoor error code..

Tap your code: 01020407080C0D10
Code What it means What to do
01 The indoor unit's room temperature sensor isn't reading properly.
Indoor ambient temperature sensor malfunction – disconnected, broken, out of position or shorted.		 🟡 Book a service call – this one needs a technician.
02 The indoor pipe (coil) temperature sensor isn't reading properly.
Indoor piping temperature sensor malfunction.		 🟡 Book a service call – this one needs a technician.
04 The indoor unit's control board has a memory fault.
Indoor PCB EEPROM error.		 🟡 Book a service call – this one needs a technician.
07 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication abnormal – wiring, addressing, power supply or PCB.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
08 The wired controller has lost communication with the indoor unit.
Wired controller to indoor unit communication abnormal (no wired-controller display for this one).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0C The condensate drain system has a fault – pump or float switch.
Drain system malfunction (LED flash count 12).		 🟡 Book a service call – the drain needs attention before it can run safely.
0D The unit can't read the incoming mains power waveform properly.
Zero-cross signal detected wrong (LED flash count 13).		 🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
10 This indoor unit is set to a different mode from the rest of the system.
Indoor abnormal mode operation – mode differs from the outdoor unit's mode (LED flash count 16).		 🟢 Set every indoor unit to the same mode (all cooling or all heating), then try again. If the code stays, book a service.

Multi console indoor units

Where the code shows: E/F codes on the indoor display panel; outdoor faults also shown as LED1 flash counts on the outdoor PCB..

Tap your code: E7E1E2E4E14F12F1F22F3F19F27F4F8F21F7F6F25F13F11F28(no indoor code)F2F23E9
Code What it means What to do
E7 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication fault. Indoor display shows E7; outdoor LED1 flashes 15 times. Haier's E7 guide has the technician check the interconnect cable, active/neutral wiring and the comms wire; if the unit runs about 4 minutes before faulting it points to the indoor PCB; with outdoor LED2 on the cause is the outdoor or indoor PCB, with LED2 off the outdoor PCB or power module.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E1 The indoor unit's room temperature sensor isn't reading properly.
Room temperature sensor failure.		 🟡 Book a service call – this one needs a technician.
E2 The indoor coil's temperature sensor isn't reading properly.
Heat-exchange sensor failure.		 🟡 Book a service call – this one needs a technician.
E4 The indoor unit's control board has a memory fault.
Indoor EEPROM error.		 🟡 Book a service call – this one needs a technician.
E14 The indoor fan motor isn't running properly.
Indoor fan motor malfunction.		 🟡 Book a service call – this one needs a technician.
F12 The outdoor unit's control board has a memory fault.
Outdoor EEPROM error. Outdoor LED1 flashes 1 time.		 🟡 Book a service call – this one needs a technician.
F1 The outdoor unit's inverter power module tripped to protect itself.
IPM protection. Outdoor LED1 flashes 2 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F22 The outdoor unit shut down because it drew too much electrical current.
AC over-current protection. Outdoor LED1 flashes 3 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F3 Two boards inside the outdoor unit (power module and main PCB) have lost communication.
IPM to outdoor PCB communication fault. Outdoor LED1 flashes 4 times.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
F19 The incoming power supply voltage is too high or too low.
Power voltage out of range. Outdoor LED1 flashes 6 times.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
F27 The compressor has locked up or keeps stopping.
Compressor lock-rotor or momentary stopping. Outdoor LED1 flashes 7 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F4 The compressor got too hot and the unit shut down to prevent damage.
Discharge temperature overheat protection. Outdoor LED1 flashes 8 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F8 The outdoor fan motor isn't running properly.
Outdoor DC fan motor fault. Outdoor LED1 flashes 9 times.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
F21 The outdoor defrost temperature sensor isn't reading properly.
Defrost temperature sensor failure. Outdoor LED1 flashes 10 times.		 🟡 Book a service call – this one needs a technician.
F7 The suction temperature sensor isn't reading properly.
Suction temperature sensor failure. Outdoor LED1 flashes 11 times.		 🟡 Book a service call – this one needs a technician.
F6 The outdoor air temperature sensor isn't reading properly.
Ambient temperature sensor failure. Outdoor LED1 flashes 12 times.		 🟡 Book a service call – this one needs a technician.
F25 The compressor discharge temperature sensor isn't reading properly.
Discharge temperature sensor failure. Outdoor LED1 flashes 13 times.		 🟡 Book a service call – this one needs a technician.
F13 The system is short of refrigerant.
Short of refrigerant. Outdoor LED1 flashes 16 times.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
F11 The compressor isn't running the way the controller expects.
Compressor deviates from normal running. Outdoor LED1 flashes 18 times.		 🟡 Book a service call – this one needs a technician.
F28 The circuit that tracks the compressor's rotor position has a fault.
Rotor position detection loop error. Outdoor LED1 flashes 19 times.		 🟡 Book a service call – this one needs a technician.
(no indoor code) An indoor unit overloaded and the system shut it down to protect it.
Overload protection of indoor system – no indoor display code; outdoor LED1 flashes 21 times.		 🟡 Check the return-air filters are clean, then book a service if the code stays.
F2 The compressor drew too much current and the unit shut down.
Compressor over-current. Outdoor LED1 flashes 24 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F23 The compressor drew too much current on one phase and the unit shut down.
Single-phase compressor over-current protection. Outdoor LED1 flashes 25 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E9 The indoor unit is working too hard and shut down to protect itself.
High work-intensity protection. Outdoor LED1 flashes 21 times (same count as the indoor overload row, as printed).		 🟡 Check the return-air filters are clean, then book a service if the code stays.

Multi hi-wall indoor units

Where the code shows: E/F codes on the indoor display panel; outdoor faults also shown as LED1 flash counts on the outdoor PCB..

Tap your code: E7E1E2E4E14F12F1F22F3F19F27F4F8F21F7F6F25F13F11F28(no indoor code)F2F23E9
Code What it means What to do
E7 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication fault. Indoor display shows E7; outdoor LED1 flashes 15 times. Haier's E7 guide has the technician check the interconnect cable, active/neutral wiring and the comms wire; if the unit runs about 4 minutes before faulting it points to the indoor PCB; with outdoor LED2 on the cause is the outdoor or indoor PCB, with LED2 off the outdoor PCB or power module.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E1 The indoor unit's room temperature sensor isn't reading properly.
Room temperature sensor failure.		 🟡 Book a service call – this one needs a technician.
E2 The indoor coil's temperature sensor isn't reading properly.
Heat-exchange sensor failure.		 🟡 Book a service call – this one needs a technician.
E4 The indoor unit's control board has a memory fault.
Indoor EEPROM error.		 🟡 Book a service call – this one needs a technician.
E14 The indoor fan motor isn't running properly.
Indoor fan motor malfunction.		 🟡 Book a service call – this one needs a technician.
F12 The outdoor unit's control board has a memory fault.
Outdoor EEPROM error. Outdoor LED1 flashes 1 time.		 🟡 Book a service call – this one needs a technician.
F1 The outdoor unit's inverter power module tripped to protect itself.
IPM protection. Outdoor LED1 flashes 2 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F22 The outdoor unit shut down because it drew too much electrical current.
AC over-current protection. Outdoor LED1 flashes 3 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F3 Two boards inside the outdoor unit (power module and main PCB) have lost communication.
IPM to outdoor PCB communication fault. Outdoor LED1 flashes 4 times.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
F19 The incoming power supply voltage is too high or too low.
Power voltage out of range. Outdoor LED1 flashes 6 times.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
F27 The compressor has locked up or keeps stopping.
Compressor lock-rotor or momentary stopping. Outdoor LED1 flashes 7 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F4 The compressor got too hot and the unit shut down to prevent damage.
Discharge temperature overheat protection. Outdoor LED1 flashes 8 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F8 The outdoor fan motor isn't running properly.
Outdoor DC fan motor fault. Outdoor LED1 flashes 9 times.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
F21 The outdoor defrost temperature sensor isn't reading properly.
Defrost temperature sensor failure. Outdoor LED1 flashes 10 times.		 🟡 Book a service call – this one needs a technician.
F7 The suction temperature sensor isn't reading properly.
Suction temperature sensor failure. Outdoor LED1 flashes 11 times.		 🟡 Book a service call – this one needs a technician.
F6 The outdoor air temperature sensor isn't reading properly.
Ambient temperature sensor failure. Outdoor LED1 flashes 12 times.		 🟡 Book a service call – this one needs a technician.
F25 The compressor discharge temperature sensor isn't reading properly.
Discharge temperature sensor failure. Outdoor LED1 flashes 13 times.		 🟡 Book a service call – this one needs a technician.
F13 The system is short of refrigerant.
Short of refrigerant. Outdoor LED1 flashes 16 times.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
F11 The compressor isn't running the way the controller expects.
Compressor deviates from normal running. Outdoor LED1 flashes 18 times.		 🟡 Book a service call – this one needs a technician.
F28 The circuit that tracks the compressor's rotor position has a fault.
Rotor position detection loop error. Outdoor LED1 flashes 19 times.		 🟡 Book a service call – this one needs a technician.
(no indoor code) An indoor unit overloaded and the system shut it down to protect it.
Overload protection of indoor system – no indoor display code; outdoor LED1 flashes 21 times.		 🟡 Check the return-air filters are clean, then book a service if the code stays.
F2 The compressor drew too much current and the unit shut down.
Compressor over-current. Outdoor LED1 flashes 24 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
F23 The compressor drew too much current on one phase and the unit shut down.
Single-phase compressor over-current protection. Outdoor LED1 flashes 25 times.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E9 The indoor unit is working too hard and shut down to protect itself.
High work-intensity protection. Outdoor LED1 flashes 21 times (same count as the indoor overload row, as printed).		 🟡 Check the return-air filters are clean, then book a service if the code stays.

Multi outdoor units (3U19FSERA, 3U24GS2ERA, 4U30HS2ERA, 5U34HS2ERA)

Where the code shows: Numeral light indicator (digital display) on the outdoor unit..

Tap your code: 124568910111213151617182021232425262728293031323334353638394042434445
Code What it means What to do
1 The outdoor unit's control board has a memory fault.
Outdoor EEPROM faulty.		 🟡 Book a service call – this one needs a technician.
2 The inverter power module tripped on over-current or a short circuit.
IPM over-current or short circuit.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
4 Two boards inside the outdoor unit (module and ECU) have lost communication.
Module-ECU communication failure.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
5 The inverter power module overloaded and shut down.
Module operated overload.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
6 The voltage inside the power module is too low or too high.
Module low or high voltage – often follows a power glitch.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
8 The compressor got too hot and the system shut down to prevent damage.
Discharge temperature overheating – lack of refrigerant, very high ambient temperature or blocked PMVs (electronic valves).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
9 The outdoor DC fan motor isn't running properly.
DC fan motor malfunction.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
10 The defrost temperature sensor isn't reading properly.
Defrosting temperature sensor malfunction.		 🟡 Book a service call – this one needs a technician.
11 The compressor suction temperature sensor isn't reading properly.
Compressor suction temperature sensor malfunction.		 🟡 Book a service call – this one needs a technician.
12 The outdoor air temperature sensor isn't reading properly.
Ambient temperature sensor malfunction.		 🟡 Book a service call – this one needs a technician.
13 The compressor discharge temperature sensor isn't reading properly.
Compressor discharge temperature sensor malfunction.		 🟡 Book a service call – this one needs a technician.
15 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication failure.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
16 The system is short of refrigerant, or refrigerant flow is restricted.
Lack of refrigerant or discharging fault.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
17 The valve that switches between heating and cooling failed to change over.
4-way valve switching failure.		 🟡 Book a service call – this one needs a technician.
18 The compressor isn't running the way the controller expects.
Loss of synchronism detection.		 🟡 Book a service call – this one needs a technician.
20 An indoor unit overheated and shut down to protect itself.
Indoor thermal overload.		 🟡 Check the return-air filters are clean, then book a service if the code stays.
21 An indoor coil started icing up and the system shut down to protect it.
Indoor frosted (anti-freeze protection).		 🟡 Check the return-air filters are clean, then book a service if the code stays.
23 The inverter power module overheated.
Module thermal overload.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
24 The compressor is failing to start.
Compressor start failure.		 🟡 Book a service call – this one needs a technician.
25 The power module drew too much input current.
Module input over-current.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
26 The outdoor unit's microcontroller reset itself – often after a power glitch.
MCU reset.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
27 The circuit that measures module current has a fault.
Module current detect circuit malfunction.		 🟡 Book a service call – this one needs a technician.
28 The liquid-pipe temperature sensor for indoor unit A isn't reading properly.
Liquid pipe temperature sensor, indoor unit A.		 🟡 Book a service call – this one needs a technician.
29 The liquid-pipe temperature sensor for indoor unit B isn't reading properly.
Liquid pipe temperature sensor, indoor unit B.		 🟡 Book a service call – this one needs a technician.
30 The liquid-pipe temperature sensor for indoor unit C isn't reading properly.
Liquid pipe temperature sensor, indoor unit C.		 🟡 Book a service call – this one needs a technician.
31 The liquid-pipe temperature sensor for indoor unit D isn't reading properly.
Liquid pipe temperature sensor, indoor unit D.		 🟡 Book a service call – this one needs a technician.
32 The gas-pipe temperature sensor for indoor unit A isn't reading properly.
Gas pipe temperature sensor, indoor unit A.		 🟡 Book a service call – this one needs a technician.
33 The gas-pipe temperature sensor for indoor unit B isn't reading properly.
Gas pipe temperature sensor, indoor unit B.		 🟡 Book a service call – this one needs a technician.
34 The gas-pipe temperature sensor for indoor unit C isn't reading properly.
Gas pipe temperature sensor, indoor unit C.		 🟡 Book a service call – this one needs a technician.
35 The gas-pipe temperature sensor for indoor unit D isn't reading properly.
Gas pipe temperature sensor, indoor unit D.		 🟡 Book a service call – this one needs a technician.
36 The gas-pipe temperature sensor for indoor unit E isn't reading properly.
Gas pipe temperature sensor, indoor unit E.		 🟡 Book a service call – this one needs a technician.
38 A temperature sensor on the power module is faulty, or a brief power failure was detected.
Module temperature sensor malfunction / momentary power failure detection.		 🟡 Book a service call – this one needs a technician.
39 The condensing (coil) temperature sensor isn't reading properly.
Condensing temperature sensor malfunction.		 🟡 Book a service call – this one needs a technician.
40 The liquid-pipe temperature sensor for indoor unit E isn't reading properly.
Liquid pipe temperature sensor, indoor unit E.		 🟡 Book a service call – this one needs a technician.
42 The system's high-pressure safety switch cut the unit out.
System high pressure switch off.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
43 The system's low-pressure safety switch cut the unit out.
System low pressure switch off.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
44 Refrigerant pressure climbed too high and the system shut down to protect itself.
System high pressure protection – refrigerant overcharge, high condensing temperature or fan motor fault.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
45 Refrigerant pressure dropped too low and the system shut down to protect itself.
System low pressure protection – refrigerant shortage, low defrosting temperature or fan motor fault.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.

Cassette indoor units (ABH071/90/105H1ERG, ABH125/140K1ERG)

Where the code shows: IR receiver digital display on the cassette panel; indoor PCB LED4 (red) tens digit, LED1 (yellow) units digit. Outdoor faults display as the hex value of (outdoor code + 20)..

Tap your code: 01020407080C0D0E
Code What it means What to do
01 The indoor unit's room temperature sensor isn't reading properly.
Indoor ambient temperature sensor malfunction – disconnected, broken, out of position or shorted.		 🟡 Book a service call – this one needs a technician.
02 The indoor pipe (coil) temperature sensor isn't reading properly.
Indoor piping temperature sensor malfunction.		 🟡 Book a service call – this one needs a technician.
04 The indoor unit's control board has a memory fault.
Indoor PCB EEPROM error.		 🟡 Book a service call – this one needs a technician.
07 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication abnormal – wiring, addressing, power supply or PCB.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
08 The wired controller has lost communication with the indoor unit.
Wired controller to indoor unit communication abnormal.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0C The condensate drain system has a fault – pump or float switch.
Drain system malfunction (LED flash count 12).		 🟡 Book a service call – the drain needs attention before it can run safely.
0D The unit can't read the incoming mains power waveform properly.
Zero-cross signal detected wrong (LED flash count 13).		 🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0E The indoor fan motor isn't running properly.
Indoor DC fan motor abnormal (LED flash count 14).		 🟡 Book a service call – this one needs a technician.

Smart power cassette – receiver display codes for outdoor faults

Where the code shows: Cassette panel IR receiver digital display (code keeps flashing). Display value is the hex of (outdoor error code + 20); both values listed per row..

Tap your code: 15161718191A1B1C1D1E1F20212223242526282A2B2C2D2E2F30393A3B3E3F4041
Code What it means What to do
15 The outdoor unit's control board has a memory fault.
Outdoor unit error code 1. Outdoor main control PCB EEPROM malfunction.		 🟡 Book a service call – this one needs a technician.
16 The inverter power module tripped on over-current.
Outdoor unit error code 2. PIM (power intelligent module) hardware over-current.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
17 The compressor drew too much current while slowing down.
Outdoor unit error code 3. Compressor over-current during deceleration.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
18 Two boards inside the outdoor unit (control board and compressor driver) have lost communication.
Outdoor unit error code 4. Control board to compressor driver module communication abnormal.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
19 The compressor drew too much current.
Outdoor unit error code 5. Compressor over-current detected by the control board.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
1A The voltage supplied to the unit is too high.
Outdoor unit error code 6. DC or AC voltage high.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
1B The circuit that measures compressor current has a fault.
Outdoor unit error code 7. Compressor current sampling circuit fault.		 🟡 Book a service call – this one needs a technician.
1C The compressor got too hot and the unit shut down to prevent damage.
Outdoor unit error code 8. Discharge temperature too high protection.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
1D The outdoor DC fan motor isn't running properly.
Outdoor unit error code 9. DC fan motor fault.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
1E The outdoor defrost temperature sensor isn't reading properly.
Outdoor unit error code 10. Defrosting temperature sensor Te abnormal.		 🟡 Book a service call – this one needs a technician.
1F The suction temperature sensor isn't reading properly.
Outdoor unit error code 11. Suction temperature sensor Ts abnormal.		 🟡 Book a service call – this one needs a technician.
20 The outdoor air temperature sensor isn't reading properly.
Outdoor unit error code 12. Outdoor ambient temperature sensor Ta abnormal.		 🟡 Book a service call – this one needs a technician.
21 The compressor discharge temperature sensor isn't reading properly.
Outdoor unit error code 13. Discharging temperature sensor Td abnormal.		 🟡 Book a service call – this one needs a technician.
22 The power-correction circuit in the outdoor unit saw too high a voltage.
Outdoor unit error code 14. PFC circuit loop high voltage.		 🟡 Book a service call – this one needs a technician.
23 The indoor and outdoor units have stopped talking to each other.
Outdoor unit error code 15. Indoor-outdoor communication abnormal.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
24 The system is short of refrigerant, or the discharge pipe is blocked.
Outdoor unit error code 16. Lack of refrigerant or discharging pipe blocked.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
25 The valve that switches between heating and cooling isn't working properly.
Outdoor unit error code 17. 4-way valve converse abnormal.		 🟡 Book a service call – this one needs a technician.
26 The compressor isn't running the way the controller expects.
Outdoor unit error code 18. Compressor motor desynchronising.		 🟡 Book a service call – this one needs a technician.
28 The indoor coil got too hot and the unit shut down to protect itself.
Outdoor unit error code 20. Indoor pipe temperature too high protection.		 🟡 Check the return-air filters are clean, then book a service if the code stays.
2A The power-correction circuit in the outdoor unit drew too much current.
Outdoor unit error code 22. PFC circuit loop over-current.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
2B The compressor driver electronics overheated.
Outdoor unit error code 23. Temperature too high for compressor driver module.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
2C The compressor is failing to start.
Outdoor unit error code 24. Compressor start failure.		 🟡 Book a service call – this one needs a technician.
2D The compressor drive module drew too much input current.
Outdoor unit error code 25. Input over-current of the drive module.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
2E The drive module's power supply is missing a phase (three-phase models).
Outdoor unit error code 26. Lack phase of the drive module power supply.		 🟡 Book a service call – this one needs a technician.
2F The circuit that measures input current has a fault.
Outdoor unit error code 27. Input current sampling circuit fault.		 🟡 Book a service call – this one needs a technician.
30 The compressor isn't wired to its drive module.
Outdoor unit error code 28. No wiring between compressor and driver module.		 🟡 Book a service call – this one needs a technician.
39 The compressor drew too much current.
Outdoor unit error code 37. Compressor over-current detected by the compressor driver module.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
3A The temperature sensor on the drive module isn't reading properly.
Outdoor unit error code 38. Drive module ambient temperature sensor abnormal.		 🟡 Book a service call – this one needs a technician.
3B The mid-coil temperature sensor isn't reading properly.
Outdoor unit error code 39. Mid-condenser temperature sensor TC abnormal.		 🟡 Book a service call – this one needs a technician.
3E The system's high-pressure safety switch has an open circuit.
Outdoor unit error code 42. High pressure switch abnormal (open circuit).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
3F The system's low-pressure safety switch has an open circuit.
Outdoor unit error code 43. Low pressure switch abnormal (open circuit).		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
40 The outdoor coil got too hot and the unit shut down to protect itself.
Outdoor unit error code 44. Outdoor condenser temperature TC too high protection.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
41 Refrigerant pressure dropped too low and the system shut down to protect itself.
Outdoor unit error code 45. System low pressure protection.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.

Low static ducted indoor units (ADH071/090/105/125/140M1ERG)

Where the code shows: Wired controller shows the code; indoor PCB LED4 (yellow) tens digit, LED3 (green) units digit. For outdoor faults: outdoor error code = (LED4 x 10 + LED3) – 20..

Tap your code: 01020407080C0D0E0F111213
Code What it means What to do
01 The indoor unit's room temperature sensor isn't reading properly.
Indoor ambient temperature sensor malfunction (LED3 flashes 1).		 🟡 Book a service call – this one needs a technician.
02 The indoor pipe (coil) temperature sensor isn't reading properly.
Indoor piping temperature sensor malfunction (LED3 flashes 2).		 🟡 Book a service call – this one needs a technician.
04 The indoor unit's control board has a memory fault.
Indoor PCB EEPROM error (LED3 flashes 4).		 🟡 Book a service call – this one needs a technician.
07 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication abnormal (LED3 flashes 7).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
08 The wired controller has lost communication with the indoor unit.
Wired controller to indoor unit communication abnormal (LED3 flashes 8).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0C The condensate drain system has a fault – pump or float switch.
Drain system malfunction (LED3 flashes 12).		 🟡 Book a service call – the drain needs attention before it can run safely.
0D The unit can't read the incoming mains power waveform properly.
Zero-cross signal detected wrong (LED3 flashes 13).		 🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0E Two boards inside the indoor unit (main PCB and fan motor drive) have lost communication.
Main control PCB to fan motor drive communication abnormal (LED3 flashes 14). NOTE: on high-static ducted models 0E means the indoor DC fan motor instead.		 🟡 Book a service call – this one needs a technician.
0F The indoor fan motor is drawing too much current.
Fan motor over-current (LED3 flashes 15).		 🟡 Book a service call – this one needs a technician.
11 The voltage feeding the indoor fan motor driver is too high or too low.
Fan motor driver DC voltage high or low (LED3 flashes 17).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
12 The indoor fan motor driver overheated.
Fan motor driver over 95 degrees C (LED3 flashes 18).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
13 The indoor fan motor has lost step with its driver.
Fan motor out of step – wrong rotor location detected (LED3 flashes 19).		 🟡 Book a service call – this one needs a technician.

High static ducted indoor units (ADH105/125/140H1ERG)

Where the code shows: Wired controller / receiver digital display. Outdoor faults display as the hex value of (outdoor code + 20)..

Tap your code: 01020407080C0D0E
Code What it means What to do
01 The indoor unit's room temperature sensor isn't reading properly.
Indoor ambient temperature sensor malfunction – disconnected, broken, out of position or shorted.		 🟡 Book a service call – this one needs a technician.
02 The indoor pipe (coil) temperature sensor isn't reading properly.
Indoor piping temperature sensor malfunction.		 🟡 Book a service call – this one needs a technician.
04 The indoor unit's control board has a memory fault.
Indoor PCB EEPROM error.		 🟡 Book a service call – this one needs a technician.
07 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication abnormal – wiring, addressing, power supply or PCB.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
08 The wired controller has lost communication with the indoor unit.
Wired controller to indoor unit communication abnormal (no wired-controller display for this one).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0C The condensate drain system has a fault – pump or float switch.
Drain system malfunction (LED flash count 12).		 🟡 Book a service call – the drain needs attention before it can run safely.
0D The unit can't read the incoming mains power waveform properly.
Zero-cross signal detected wrong (LED flash count 13).		 🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
0E The indoor fan motor isn't running properly.
Indoor DC fan motor abnormal (LED flash count 14).		 🟡 Book a service call – this one needs a technician.

Ducted outdoor units (1UH090/105/125/140 N/P 1ERG(K))

Where the code shows: LED3 digital display on the outdoor control board shows the error code and keeps flashing. 'Non-resumable' faults only clear after fixing the cause and cycling power..

Tap your code: 12345678910111213141516171819202223242526272837383942434445
Code What it means What to do
1 The outdoor unit's control board has a memory fault.
EEPROM chip damaged or data wrong. (non-resumable)		 🟡 Book a service call – this one needs a technician.
2 The inverter power module tripped on over-current.
PIM hardware over-current detected. (resumable)		 🔴 Turn the system off at the isolator and call us – don't keep running it.
3 The compressor drew too much current while slowing down.
Compressor over-current during deceleration. (non-resumable)		 🔴 Turn the system off at the isolator and call us – don't keep running it.
4 Two boards inside the outdoor unit (control board and compressor driver) have lost communication.
Control board unable to communicate with the compressor driver module for over 4 minutes. (resumable)		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
5 The compressor drew too much current.
Compressor over-current detected by the control board. (non-resumable)		 🔴 Turn the system off at the isolator and call us – don't keep running it.
6 The voltage supplied to the unit is too high.
AC supply over 280 V or DC bus over 390 V. (resumable)		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
7 The circuit that measures compressor current has a fault.
Compressor current sampling circuit damaged. (non-resumable)		 🟡 Book a service call – this one needs a technician.
8 The compressor got too hot and the unit shut down to prevent damage.
Discharge temperature over 115 degrees C; locks out after 3 trips in an hour. (non-resumable)		 🔴 Turn the system off at the isolator and call us – don't keep running it.
9 The outdoor DC fan motor isn't running properly.
DC fan motor damaged, disconnected or circuit broken; locks after 3 trips in 30 minutes. (non-resumable)		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
10 The outdoor defrost temperature sensor isn't reading properly.
Defrost sensor Te out of range, short or open circuit. (resumable)		 🟡 Book a service call – this one needs a technician.
11 The suction temperature sensor isn't reading properly.
Suction sensor Ts out of range, short or open circuit. (resumable)		 🟡 Book a service call – this one needs a technician.
12 The outdoor air temperature sensor isn't reading properly.
Ambient sensor Ta out of range, short or open circuit. (resumable)		 🟡 Book a service call – this one needs a technician.
13 The compressor discharge temperature sensor isn't reading properly.
Discharge sensor Td out of range, short or open circuit. (resumable)		 🟡 Book a service call – this one needs a technician.
14 The power-correction circuit in the outdoor unit saw too high a voltage.
Over-voltage in the driver module's PFC circuit loop. (resumable)		 🟡 Book a service call – this one needs a technician.
15 The indoor and outdoor units have stopped talking to each other.
Outdoor control board unable to communicate with the indoor control board for over 4 minutes. (resumable)		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
16 The system is short of refrigerant, or the discharge pipe is blocked.
Discharge/suction temperature difference over 80 degrees C after 10 minutes' running; locks after 3 trips in an hour. (non-resumable)		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
17 The valve that switches between heating and cooling isn't working properly.
4-way valve reversing abnormal; locks after 3 trips in an hour. (non-resumable)		 🟡 Book a service call – this one needs a technician.
18 The compressor isn't running the way the controller expects.
Rotor desynchronising – overload, sharply fluctuating load, current sensor fault or missing inverter gate signal. (non-resumable)		 🟡 Book a service call – this one needs a technician.
19 The voltage supplied to the unit is too low.
AC supply under 155 V or DC bus under 180 V. (resumable)		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
20 The indoor coil got too hot and the unit shut down to protect itself.
Indoor pipe temperature over 63 degrees C; clears when it falls below 52 degrees C. (resumable)		 🟡 Check the return-air filters are clean, then book a service if the code stays.
22 The power-correction circuit in the outdoor unit drew too much current.
Over-current in the PFC circuit loop. (resumable)		 🔴 Turn the system off at the isolator and call us – don't keep running it.
23 The compressor driver electronics overheated.
Driver module PIM temperature over 90 degrees C; locks after 3 trips in an hour. (non-resumable)		 🔴 Turn the system off at the isolator and call us – don't keep running it.
24 The compressor is failing to start.
Compressor start failure detected by the driver module. (non-resumable)		 🟡 Book a service call – this one needs a technician.
25 The compressor drive module drew too much input current.
Input current over 32 A (double-fan) or 27 A (single-fan); locks after 3 trips in an hour. (non-resumable)		 🔴 Turn the system off at the isolator and call us – don't keep running it.
26 The drive module's power supply is missing a phase (three-phase models).
Lack of phase in the drive module power supply. (non-resumable)		 🟡 Book a service call – this one needs a technician.
27 The circuit that measures input current has a fault.
Driver module input current sampling circuit damaged. (resumable)		 🟡 Book a service call – this one needs a technician.
28 The compressor isn't wired to its drive module.
No wiring between compressor and driver module. (non-resumable)		 🟡 Book a service call – this one needs a technician.
37 The compressor drew too much current.
Compressor phase current over 27 A / 19.1 A during non-rated running, detected by the driver module. (resumable)		 🔴 Turn the system off at the isolator and call us – don't keep running it.
38 The temperature sensor on the drive module isn't reading properly.
Drive module ambient sensor outside -25 to 150 degrees C. (resumable)		 🟡 Book a service call – this one needs a technician.
39 The mid-coil temperature sensor isn't reading properly.
Mid-condenser sensor TC outside -55 to 90 degrees C. (resumable)		 🟡 Book a service call – this one needs a technician.
42 The system's high-pressure safety switch tripped or is faulty.
High pressure switch open circuit for 30 seconds after 3 minutes' running; locks after 3 trips in an hour. (non-resumable)		 🔴 Turn the system off at the isolator and call us – don't keep running it.
43 The system's low-pressure safety switch tripped or is faulty.
Low pressure switch disconnected 60 seconds running / 30 seconds standby. (non-resumable)		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
44 The outdoor coil got too hot and the unit shut down to protect itself.
Maximum of Tc/Te over 65 degrees C; locks after 3 trips in 30 minutes. (non-resumable)		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
45 System pressure dropped abnormally low and the unit shut down to protect itself.
Indoor pipe Tm and outdoor Ts below -45 degrees C in cooling, or outdoor Tc and Te below -45 degrees C. (non-resumable)		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.

Inverter (IPM) module board, single-phase (1UH071/090/105N1ERG)

Where the code shows: LED601 (green) on the module board inside the outdoor unit – technician access only. Normal running: 1s on / 1s off. Fault: flashes n times at 0.25s then 2s off, where n is the error code..

Tap your code: 1234678911121314151619202122
Code What it means What to do
1 The inverter power module overheated.
PIM module overheat – 105 degrees C sustained 5 seconds (symbol 01H).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
2 The power module's temperature sensor circuit failed.
PIM temperature sampling failure (symbol 18H).		 🟡 Book a service call – this one needs a technician.
3 The module tripped on over-current at its frequency limit.
Over-current protection when at limit frequency (symbol 02H).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
4 The power module's hardware protection tripped.
Hardware protection PIM_INT (symbol 04H).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
6 The DC voltage inside the module is too low.
DC under-voltage (symbol 05H).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
7 The DC voltage inside the module is too high.
DC high voltage (symbol 06H).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
8 The module has lost communication with the main board.
Communication error (symbol 07H).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
9 One of the module's output phases to the compressor is missing.
Output lack of phase (symbol 16H).		 🟡 Book a service call – this one needs a technician.
11 The compressor's U phase drew too much current.
U phase over-current, 40 A level (symbol 0AH).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
12 The compressor has lost step with its driver.
Compressor out of step (symbol 0EH).		 🟡 Book a service call – this one needs a technician.
13 The compressor's V phase drew too much current.
V phase over-current, 40 A level (symbol 0CH).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
14 The compressor's W phase drew too much current.
W phase over-current, 40 A level (symbol 0DH).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
15 The compressor failed to start.
Compressor startup failure (symbol 0FH).		 🟡 Book a service call – this one needs a technician.
16 The circuit that measures compressor phase current failed.
Phase current sampling failure (symbol 09H).		 🟡 Book a service call – this one needs a technician.
19 The incoming AC supply voltage is too low.
AC input under-voltage, 155 V level (symbol 11H).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
20 The incoming AC supply voltage is too high.
AC input over-voltage, 280 V level (symbol 12H).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
21 The unit drew too much current from the mains.
AC input over-current, 35 A level (symbol 13H).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
22 The circuit that measures input current failed.
Input current sampling failure (symbol 08H).		 🟡 Book a service call – this one needs a technician.

Inverter (IPM) module board, three-phase (1UH125/140P1ERK)

Where the code shows: LED601 (green) on the module board inside the outdoor unit – technician access only. Same flash scheme as the single-phase board..

Tap your code: 1234678911121314151622
Code What it means What to do
1 The inverter power module overheated.
PIM module overheat – 105 degrees C sustained 5 seconds (symbol 01H).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
2 The power module's temperature sensor circuit failed.
PIM temperature sampling failure (symbol 18H).		 🟡 Book a service call – this one needs a technician.
3 The module tripped on over-current at its frequency limit.
Over-current protection when at limit frequency (symbol 02H).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
4 The power module's hardware protection tripped.
Hardware protection PIM_INT (symbol 04H).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
6 The DC voltage inside the module is too low.
DC under-voltage (symbol 05H).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
7 The DC voltage inside the module is too high.
DC high voltage (symbol 06H).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
8 The module has lost communication with the main board.
Communication error (symbol 07H).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
9 One of the module's output phases to the compressor is missing.
Output lack of phase (symbol 16H).		 🟡 Book a service call – this one needs a technician.
11 The compressor's U phase drew too much current.
U phase over-current, 40 A level (symbol 0AH).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
12 The compressor has lost step with its driver.
Compressor out of step (symbol 0EH).		 🟡 Book a service call – this one needs a technician.
13 The compressor's V phase drew too much current.
V phase over-current, 40 A level (symbol 0CH).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
14 The compressor's W phase drew too much current.
W phase over-current, 40 A level (symbol 0DH).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
15 The compressor failed to start.
Compressor startup failure (symbol 0FH).		 🟡 Book a service call – this one needs a technician.
16 The circuit that measures compressor phase current failed.
Phase current sampling failure (symbol 09H).		 🟡 Book a service call – this one needs a technician.
22 The incoming three-phase supply is missing a phase.
Input lack of phase – hardware protection (symbol 10H). 3-phase board DC levels: under-voltage 300 V, high voltage 700 V.		 🟡 Book a service call – this one needs a technician.

Code still showing after a reset? Mention the code and your system type when you book and our office can line up the right technician and likely parts before we arrive.

Book a service  or call (02) 4760 0100 (24-hour line, Penrith & Blue Mountains).

Codes vary between models and generations, and manufacturers revise them. This guide is compiled from official service documentation and checked by Ample Air, but it is general information, not a diagnosis. Refrigerant and electrical work must be carried out by licensed technicians. Ample Air, ARC licences AU12976 & AU15788. Last verified August 2026.

LG air conditioner CH fault codes

by | Aug 3, 2026

When your LG system stops and shows a code, that code is the system telling you roughly where the problem is. Roughly is the key word. A fault code points in a direction, it rarely names the exact fix. Find your system below, tap your code, and it will take you straight to what it means and what to do.

Before you try anything: the only DIY steps that are ever safe are switching the system off at the isolator (and waiting 20 to 30 minutes), cleaning or checking filters, checking the controller settings and batteries, and keeping the outdoor unit clear. Anything behind a panel, anything electrical, and anything involving refrigerant or gas is licensed work. If a code below says switch off and call, please take it at its word.

How to read the tables: 🟢 means there is a safe first step worth trying. 🟡 means book a service, the system needs a technician. 🔴 means switch the system off at the isolator and call us on (02) 4760 0100.

Residential splits (RAC) – CH codes

Where the code shows: Shown as CHxx on the indoor unit display or wired remote controller. Some models show only the number, or a short C-form (C1-C9, CA, CC, Cd, CE)..

Tap your code: CH01CH02CH03CH04CH05CH06CH07CH08CH09CH10CH12CH21CH22CH23CH24CH25CH26CH27CH28CH32CH33CH34CH35CH40CH41CH42CH43CH44CH45CH46CH47CH48CH49CH51CH52CH53CH54CH57CH60CH61CH62CH65CH67C1C2C4C5C6C7C8C9CACCCdCECLPoHL
Code What it means What to do
CH01 The indoor unit's return-air temperature sensor isn't reading properly.
Indoor return air sensor open/short.		 🟡 Book a service call – this one needs a technician.
CH02 The indoor pipe sensor or the outdoor sensor assembly isn't reading properly.
Indoor pipe sensor / outdoor sensor assembly open or short.		 🟡 Book a service call – this one needs a technician.
CH03 The wired remote controller has lost communication with the indoor unit.
Remote controller comms error – wiring or controller dip-switch setting (Sg for single unit, Gr for group).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH04 The temperature sensor on the outdoor electronics heatsink is faulty or has overheated.
On residential (RAC) units: heat-sink sensor open/short or over 95 degrees C. On commercial indoor units this code means the drain float switch has risen – see the ducted/cassette list.		 🟡 Book a service call – this one needs a technician.
CH05 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH06 The indoor coil's temperature sensor isn't reading properly.
Indoor coil sensor fault.		 🟡 Book a service call – this one needs a technician.
CH07 The compressor drew too much current and the unit shut down. (On multi-head systems this same code means an indoor-unit mode conflict instead – see the multi-split list.)
Single splits: compressor over-current (CT2).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH08 The indoor fan motor is jammed or not spinning.
Indoor BLDC fan locked / fan motor or fan PCB fault.		 🟡 Book a service call – this one needs a technician.
CH09 The outdoor fan motor isn't running properly.
Outdoor fan motor or outdoor PCB fault (single splits).		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
CH10 The compressor discharge temperature sensor isn't reading properly.
Compressor discharge sensor fault (residential units). On Multi F(DX) and Multi V this code points to the indoor fan fault instead.		 🟡 Book a service call – this one needs a technician.
CH12 The temperature sensor on the middle of the indoor unit's coil isn't reading properly.
Indoor middle-pipe thermistor open/short (the companion coil sensors are CH02 pipe-inlet and CH06 pipe-outlet). The keyword list called 12 an 'EEPROM sum check error', but no other LG source agrees and the list's own CH12 entry disowns the code – corrected to LG's documented meaning.		 🟡 Book a service call – this one needs a technician.
CH21 The inverter compressor is drawing too much current.
Inverter compressor run current high (DC peak). The source gives CH21 and CH22 identical wording.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH22 The inverter compressor is drawing too much current.
Inverter compressor run current high (max current). The source gives CH21 and CH22 identical wording.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH23 The voltage inside the outdoor unit's inverter has dropped too low.
Inverter DC voltage low – often follows a power dip or brownout.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH24 The system tripped on refrigerant pressure – too high or too low.
High/low pressure trip (low ~1 bar, high ~35 bar) on splits and multi splits.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH25 The incoming power supply voltage is outside the unit's safe range.
Input voltage error (230 V single-phase / 400 V three-phase, +/-10%).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH26 The inverter compressor has seized or won't turn.
Inverter compressor seized / locked rotor.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH27 The inverter is measuring irregular electrical current.
Inverter current irregularity – inverter PCB or reactor.		 🟡 Book a service call – this one needs a technician.
CH28 The voltage inside the outdoor unit's inverter has risen too high.
Inverter DC voltage too high – often follows a power surge.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH32 The inverter compressor got too hot and the unit shut down to prevent damage.
Inverter compressor discharge temperature over ~105 degrees C – can point to low refrigerant.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
CH33 The standard compressor got too hot and the unit shut down to prevent damage.
Standard compressor discharge temperature over ~105 degrees C – can point to low refrigerant.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
CH34 Refrigerant pressure climbed far too high and the unit shut down to protect itself.
High-pressure trip over ~35 bar – blocked coils, dirty filters or non-condensables in the pipework.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH35 Refrigerant pressure dropped far too low and the unit shut down to protect itself.
Low-pressure trip under ~1 bar – can point to refrigerant loss or closed service valves.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
CH40 The inverter is measuring abnormal AC current to the compressor.
Inverter AC current abnormal (CT sensor circuit).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH41 The inverter compressor's discharge temperature sensor isn't reading properly.
Inverter compressor discharge sensor fault.		 🟡 Book a service call – this one needs a technician.
CH42 The low-pressure sensor isn't reading properly.
Low pressure sensor fault.		 🟡 Book a service call – this one needs a technician.
CH43 The high-pressure sensor isn't reading properly.
High pressure sensor fault.		 🟡 Book a service call – this one needs a technician.
CH44 The outdoor air temperature sensor isn't reading properly.
Outdoor air sensor fault.		 🟡 Book a service call – this one needs a technician.
CH45 The outdoor coil temperature sensor isn't reading properly.
Outdoor coil sensor fault.		 🟡 Book a service call – this one needs a technician.
CH46 The outdoor unit's suction temperature sensor isn't reading properly.
Outdoor suction sensor fault.		 🟡 Book a service call – this one needs a technician.
CH47 The compressor discharge temperature sensor isn't reading properly.
Compressor discharge sensor fault.		 🟡 Book a service call – this one needs a technician.
CH48 Two outdoor sensors (discharge and air) are both unplugged or not reading.
Outdoor discharge and air sensors both open (splits/multi splits). On Multi V this code means the outdoor coil sensor instead.		 🟡 Book a service call – this one needs a technician.
CH49 The incoming power supply voltage is outside the unit's safe range.
Input voltage error (230 V single-phase / 400 V three-phase, +/-10%).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH51 The connected indoor units add up to more capacity than the outdoor unit allows.
Unit capacity mismatch / over-combination.		 🟡 Book a service call – this one needs a technician.
CH52 The outdoor unit's two circuit boards (main and inverter) have lost communication with each other.
Main PCB to inverter PCB communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH53 The indoor and outdoor units have stopped talking to each other.
Indoor to outdoor communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH54 The three-phase power supply has a phase missing or connected in the wrong order.
Reverse or open phase (three-phase models) – needs an electrician or technician.		 🟡 Book a service call – this one needs a technician.
CH57 The outdoor unit's two circuit boards (main and inverter) have lost communication with each other.
Main PCB to inverter PCB communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH60 The outdoor unit's control board has a memory (EEPROM) fault.
Outdoor PCB EEPROM failure.		 🟡 Book a service call – this one needs a technician.
CH61 The outdoor coil got too hot – usually blocked airflow or a dirty coil.
Condenser coil temperature over ~65 degrees C.		 🟡 Check nothing is blocking the outdoor unit and clear leaves or debris away from it, then book a service if the code returns.
CH62 The outdoor unit's inverter electronics overheated and the unit shut down to protect itself.
Inverter heatsink over ~85 degrees C.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH65 The temperature sensor on the inverter heatsink isn't reading properly.
Inverter fin temperature sensor fault.		 🟡 Book a service call – this one needs a technician.
CH67 The outdoor fan motor has seized or its rotation can't be detected.
Outdoor fan motor locked / rotation-sensing failure.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
C1 The indoor unit's return-air temperature sensor isn't reading properly.
Short display form of CH01.		 🟡 Book a service call – this one needs a technician.
C2 The indoor pipe sensor or the outdoor sensor assembly isn't reading properly.
Short display form of CH02.		 🟡 Book a service call – this one needs a technician.
C4 The heatsink temperature sensor is faulty or has overheated (residential units).
Short display form of CH04. On commercial indoor units this code means the drain float switch has risen.		 🟡 Book a service call – this one needs a technician.
C5 The indoor and outdoor units have stopped talking to each other.
Short display form of CH05.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
C6 The inverter compressor is drawing too much current.
NOTE: the source lists C6 as compressor run-current high (the CH21/22 fault), NOT the CH06 coil-sensor fault – do not read C6 as CH06.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
C7 The compressor drew too much current and the unit shut down.
Compressor over-current (CT2) – short form of the splits meaning of CH07.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
C8 The indoor fan motor is jammed or not spinning.
Short display form of CH08.		 🟡 Book a service call – this one needs a technician.
C9 The outdoor fan motor isn't running properly.
Short display form of CH09.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
CA The compressor discharge temperature sensor isn't reading properly.
Hex-style short form of code 10 (discharge sensor fault).		 🟡 Book a service call – this one needs a technician.
CC The outdoor control board has a memory (EEPROM) fault.
Hex-style short form of code 12 (EEPROM sum-check error).		 🟡 Book a service call – this one needs a technician.
Cd The unit's power-factor circuit (PSC/reactor) has a fault.
Hex-style short form of code 13 (PSC/reactor error).		 🟡 Book a service call – this one needs a technician.
CE The compressor is drawing abnormal current on one of its phases.
Hex-style short form of code 14 (compressor phase current error).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CL Child lock is switched on – this is a setting, not a fault.
Child lock display.		 🟢 Press the Timer and Min buttons together for 5 seconds to turn child lock off.
Po The unit is running in Jet Cool (power cool) mode – this is a setting, not a fault.
Jet Cool mode display.		 🟢 Press the Jet Cool, Fan Speed or Set Temperature button to return to normal operation.
HL The condensate drain safety switch has risen – the drain pan or pump needs attention.
Float switch risen (units with a drain pump). Can also mean an attached Dry Contact interface is set to OFF.		 🟡 Book a service call – the drain needs attention before it can run safely.

Multi split / Multi F(DX) – codes whose meaning differs from the single-split list

Where the code shows: Shown as CHxx on the indoor unit display or wired remote controller. Codes not listed here read the same as the residential split list..

Tap your code: CH05CH07CH10CH24CH51CH63
Code What it means What to do
CH05 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH07 One indoor unit is set to a different mode from the others – a multi system can only heat or cool, not both at once.
Indoor unit mode conflict with the master indoor unit.		 🟢 Set every indoor unit to the same mode (all cooling or all heating), then try again. If the code stays, book a service.
CH10 An indoor fan motor is jammed or not spinning.
On Multi F(DX) code 10 refers to the indoor BLDC fan fault (the code-08 fault on splits).		 🟡 Book a service call – this one needs a technician.
CH24 The system tripped on refrigerant pressure – too high or too low.
High/low pressure trip (low ~1 bar, high ~35 bar).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH51 The connected indoor units add up to more capacity than the outdoor unit allows.
Unit capacity mismatch / over-combination.		 🟡 Book a service call – this one needs a technician.
CH63 The outdoor coil pipe sensor is reading abnormally cold.
Multi F(DX) only: condenser pipe temperature low (the opposite condition to code 61).		 🟡 Book a service call – this one needs a technician.

Multi V (VRF) – including multi-outdoor sub units and heat-recovery boxes

Where the code shows: Shown as CHxx on indoor units/wired controllers; outdoor-module (sub unit) codes 100+ display on the outdoor unit PCB. Codes not listed here read the same as the residential split list..

Tap your code: CH05CH07CH09CH10CH11CH24CH42CH43CH48CH51CH62CH104CH105CH106CH107CH108CH109CH110CH111CH113CH114CH115CH116CH117CH118CH120CH121CH122CH123CH124CH125CH126CH127CH128CH129CH130CH132CH133CH134CH135CH136CH137CH138CH139CH140CH141CH142CH144CH146CH151CH154CH155CH156CH157CH158CH159CH161CH162CH163CH164CH165CH166CH167CH168CH170CH173CH174CH175CH176CH177CH204CH208CH212
Code What it means What to do
CH05 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication error (Multi V comms bus).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH07 One indoor unit is set to a different mode from the others – the system can only heat or cool, not both at once (unless fitted with heat-recovery boxes).
Indoor unit mode conflict with the master indoor unit.		 🟢 Set every indoor unit to the same mode (all cooling or all heating), then try again. If the code stays, book a service.
CH09 An indoor unit's control board has a memory (EEPROM) fault.
Multi V: indoor EEPROM error – board replacement plus re-addressing.		 🟡 Book a service call – this one needs a technician.
CH10 An indoor fan motor is jammed or not spinning.
Multi V: code 10 refers to the indoor BLDC fan fault.		 🟡 Book a service call – this one needs a technician.
CH11 An indoor unit isn't registered with the outdoor unit.
Indoor unit not connected / not initialised on the comms bus.		 🟡 Book a service call – this one needs a technician.
CH24 The system shut down because refrigerant pressure climbed too high.
Multi V: high pressure trip.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH42 The low-pressure sensor isn't reading properly.
Low pressure sensor fault.		 🟡 Book a service call – this one needs a technician.
CH43 The high-pressure sensor isn't reading properly.
High pressure sensor fault.		 🟡 Book a service call – this one needs a technician.
CH48 The outdoor coil temperature sensor isn't reading properly.
Multi V meaning of code 48 (on splits it means two sensors unplugged).		 🟡 Book a service call – this one needs a technician.
CH51 The connected indoor units add up to more capacity than the outdoor units allow, or a sub outdoor unit is set up incorrectly.
Over-combination / sub outdoor unit dip-switch settings.		 🟡 Book a service call – this one needs a technician.
CH62 The inverter electronics overheated and the unit shut down to protect itself.
Inverter heatsink over ~85 degrees C; Multi V also has an inverter cooling fan that can fail.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH104 The main and sub outdoor units have stopped talking to each other.
Main-sub outdoor unit communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH105 Two boards inside the outdoor unit (main PCB and fan PCB) have lost communication.
Main PCB to fan PCB communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH106 An outdoor fan motor is drawing too much current.
Outdoor fan motor high current.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
CH107 The outdoor fan control board isn't getting enough voltage.
Low DC voltage to fan PCB.		 🟡 Book a service call – this one needs a technician.
CH108 Two boards inside the outdoor unit (main PCB and fan PCB) have lost communication.
Main PCB to fan PCB communication error (duplicate of 105 in the source).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH109 Refrigerant pressure climbed too high on this outdoor module and it shut down to protect itself.
Sub 1 excessive high-pressure rise.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH110 This outdoor module's three-phase power supply has a phase missing or connected in the wrong order.
Sub 1 reverse or open phase.		 🟡 Book a service call – this one needs a technician.
CH111 The main and sub outdoor units have stopped talking to each other.
Main-sub outdoor unit communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH113 The main outdoor unit's liquid pipe sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH114 The main outdoor unit's subcool inlet sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH115 The main outdoor unit's subcool outlet sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH116 The sub 1 outdoor unit's high-pressure sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH117 The sub 1 outdoor unit's low-pressure sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH118 The sub 1 outdoor unit's air temperature sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH120 The sub 1 outdoor unit's suction temperature sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH121 The sub 1 unit's compressor 1 discharge sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH122 The sub 1 unit's compressor 2 discharge sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH123 The sub 1 outdoor unit's coil sensor A isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH124 The sub 1 outdoor unit's coil sensor B isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH125 The sub 1 outdoor unit's liquid pipe sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH126 The sub 1 outdoor unit's subcool inlet sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH127 The sub 1 outdoor unit's subcool outlet sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH128 The sub 2 outdoor unit's high-pressure sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH129 The sub 2 outdoor unit's low-pressure sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH130 The sub 2 outdoor unit's air temperature sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH132 The sub 2 outdoor unit's suction temperature sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH133 The sub 2 unit's compressor 1 discharge sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH134 The sub 2 unit's compressor 2 discharge sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH135 The sub 2 outdoor unit's coil sensor A isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH136 The sub 2 outdoor unit's coil sensor B isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH137 The sub 2 outdoor unit's liquid pipe sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH138 The sub 2 outdoor unit's subcool inlet sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH139 The sub 2 outdoor unit's subcool outlet sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH140 Refrigerant pressure climbed too high on this outdoor module and it shut down to protect itself.
Sub 2 excessive high-pressure rise.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH141 This outdoor module's three-phase power supply has a phase missing or connected in the wrong order.
Sub 2 reverse or open phase.		 🟡 Book a service call – this one needs a technician.
CH142 The main and sub outdoor units have stopped talking to each other.
Main-sub outdoor unit communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH144 Refrigerant pressure dropped too low on this outdoor module and it shut down to protect itself.
Sub 1 excessive low-pressure drop.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
CH146 Refrigerant pressure dropped too low on this outdoor module and it shut down to protect itself.
Sub 2 excessive low-pressure drop.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
CH151 The valve that switches the system between heating and cooling has failed.
Faulty 4-way (reversing) valve.		 🟡 Book a service call – this one needs a technician.
CH154 Refrigerant pressure climbed too high on this outdoor module and it shut down to protect itself.
Sub 3 excessive high-pressure rise.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
CH155 This outdoor module's three-phase power supply has a phase missing or connected in the wrong order.
Sub 3 reverse or open phase.		 🟡 Book a service call – this one needs a technician.
CH156 The main and sub outdoor units have stopped talking to each other.
Main-sub outdoor unit communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
CH157 The sub 3 outdoor unit's high-pressure sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH158 The sub 3 outdoor unit's low-pressure sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH159 The sub 3 outdoor unit's air temperature sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH161 The sub 3 outdoor unit's suction temperature sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH162 The sub 3 unit's compressor 1 discharge sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH163 The sub 3 unit's compressor 2 discharge sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH164 The sub 3 outdoor unit's coil sensor A isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH165 The sub 3 outdoor unit's coil sensor B isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH166 The sub 3 outdoor unit's liquid pipe sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH167 The sub 3 outdoor unit's subcool inlet sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH168 The sub 3 outdoor unit's subcool outlet sensor isn't reading properly.
Sensor open/short – technician diagnosis.		 🟡 Book a service call – this one needs a technician.
CH170 Refrigerant pressure dropped too low on this outdoor module and it shut down to protect itself.
Sub 3 excessive low-pressure drop.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
CH173 A compressor on the main outdoor unit is failing to start.
Main unit standard compressor not starting – PCB output, contactor or compressor.		 🟡 Book a service call – this one needs a technician.
CH174 A compressor on sub outdoor unit 1 is failing to start.
Sub 1 standard compressor 1 not starting.		 🟡 Book a service call – this one needs a technician.
CH175 A compressor on sub outdoor unit 1 is failing to start.
Sub 1 standard compressor 2 not starting.		 🟡 Book a service call – this one needs a technician.
CH176 A compressor on sub outdoor unit 2 is failing to start.
Sub 2 standard compressor 1 not starting.		 🟡 Book a service call – this one needs a technician.
CH177 A compressor on sub outdoor unit 2 is failing to start.
Sub 2 standard compressor 2 not starting.		 🟡 Book a service call – this one needs a technician.
CH204 The outdoor unit has lost communication with heat-recovery box 1.
HR box 1 comms – power/transmission connections, rotary/dip switch settings, or HR unit PCB.		 🟡 Book a service call – this one needs a technician.
CH208 The outdoor unit has lost communication with heat-recovery box 2.
HR box 2 comms – power/transmission connections, rotary/dip switch settings, or HR unit PCB.		 🟡 Book a service call – this one needs a technician.
CH212 The outdoor unit has lost communication with heat-recovery box 3.
HR box 3 comms – power/transmission connections, rotary/dip switch settings, or HR unit PCB.		 🟡 Book a service call – this one needs a technician.

Central controller / CNU (codes 240-253)

Where the code shows: Shown on the central controller..

Tap your code: 240241242243244245246250251252253
Code What it means What to do
240 The central controller's wiring isn't connecting it to the system properly.
Central controller wiring error – comms wiring, CNU, IP addresses.		 🟡 Book a service call – this one needs a technician.
241 The central controller can't send data to the system.
Data sending error – CNU or controller initialisation.		 🟡 Book a service call – this one needs a technician.
242 The central controller can't receive data from the system.
Data receiving error – CNU or controller initialisation.		 🟡 Book a service call – this one needs a technician.
243 The central controller's communication line is too long or picking up electrical interference.
Comms cable length / electrical noise, controller mismatch, or CNU.		 🟡 Book a service call – this one needs a technician.
244 The central controller timed out waiting to receive data.
Data receiving time-out – CNU or controller initialisation.		 🟡 Book a service call – this one needs a technician.
245 The central controller timed out trying to send data.
Data sending time-out – CNU or controller initialisation.		 🟡 Book a service call – this one needs a technician.
246 The central controller timed out waiting to receive data.
Data receiving time-out (duplicate of 244 in the source).		 🟡 Book a service call – this one needs a technician.
250 The central controller is receiving corrupted data.
Data receiving error – electrical noise on the comms cable or CNU.		 🟡 Book a service call – this one needs a technician.
251 The central controller is receiving no data at all.
No data received – electrical noise on the comms cable or CNU.		 🟡 Book a service call – this one needs a technician.
252 The central controller's address settings don't match the system.
Incorrect address error.		 🟡 Book a service call – this one needs a technician.
253 The central controller is getting no response from the air conditioner.
Disconnection error – wiring, electrical noise, CNU or interface.		 🟡 Book a service call – this one needs a technician.

Commercial indoor units (ducted/cassette) – codes whose meaning differs from the split list

Where the code shows: Shown as CHxx (or HL) on the wired remote controller. Codes not listed here read the same as the residential split list..

Tap your code: CH04HL
Code What it means What to do
CH04 The condensate drain safety switch has risen – the drain pan or pump needs attention.
Commercial indoor units (ducted/cassette): condensate pump float switch risen. On residential wall splits this same code means a heatsink sensor fault instead.		 🟡 Book a service call – the drain needs attention before it can run safely.
HL The condensate drain safety switch has risen – the drain pan or pump needs attention.
Float switch risen. Can also mean an attached Dry Contact interface is set to OFF.		 🟡 Book a service call – the drain needs attention before it can run safely.

Code still showing after a reset? Mention the code and your system type when you book and our office can line up the right technician and likely parts before we arrive.

Book a service  or call (02) 4760 0100 (24-hour line, Penrith & Blue Mountains).

Codes vary between models and generations, and manufacturers revise them. This guide is compiled from official service documentation and checked by Ample Air, but it is general information, not a diagnosis. Refrigerant and electrical work must be carried out by licensed technicians. Ample Air, ARC licences AU12976 & AU15788. Last verified August 2026.

Samsung air conditioner fault codes

by | Aug 3, 2026

When your Samsung system stops and shows a code, that code is the system telling you roughly where the problem is. Roughly is the key word. A fault code points in a direction, it rarely names the exact fix. Find your system below, tap your code, and it will take you straight to what it means and what to do.

Before you try anything: the only DIY steps that are ever safe are switching the system off at the isolator (and waiting 20 to 30 minutes), cleaning or checking filters, checking the controller settings and batteries, and keeping the outdoor unit clear. Anything behind a panel, anything electrical, and anything involving refrigerant or gas is licensed work. If a code below says switch off and call, please take it at its word.

How to read the tables: 🟢 means there is a safe first step worth trying. 🟡 means book a service, the system needs a technician. 🔴 means switch the system off at the isolator and call us on (02) 4760 0100.

Wall-mounted splits without a code display (status-LED models)

Where the code shows: Indoor unit status LEDs read left to right: LED1 = Operation, LED2 = Timer, LED3 = S-Plasma Ion. Patterns below are LED1-LED2-LED3 (OFF / BLINK / ON). Outdoor faults also show a pattern on the outdoor PCB LEDs..

Tap your code: OFF-BLINK-BLINK (indoor LEDs)OFF-BLINK-OFF (indoor LEDs)BLINK-BLINK-OFF (indoor LEDs)BLINK-OFF-BLINK (indoor LEDs)OFF-OFF-BLINK (indoor LEDs)ON-BLINK-BLINK (outdoor LEDs)BLINK-OFF-BLINK (outdoor LEDs)BLINK-BLINK-OFF (outdoor LEDs)BLINK-OFF-ON (outdoor LEDs)ON-OFF-OFF (outdoor LEDs)ON-OFF-ON (outdoor LEDs)OFF-ON-BLINK (outdoor LEDs)ON-BLINK-ON (outdoor LEDs)BLINK-ON-OFF (outdoor LEDs)OFF-ON-OFF / ON-OFF-BLINK (outdoor LEDs)ON-ON-BLINK (outdoor LEDs)BLINK-OFF-OFF (outdoor LEDs)ON-ON-OFF (outdoor LEDs)OFF-OFF-BLINK (outdoor LEDs)ALL indoor LEDs flashing
Code What it means What to do
ON-OFF-OFF (outdoor LEDs) The outdoor fan motor isn't running properly.
Outdoor fan motor error.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
ON-OFF-ON (outdoor LEDs) The outdoor unit can't drive the compressor properly – a compressor wiring or rotation fault.
Compressor wire missing / rotation error.		 🟡 Book a service call – this one needs a technician.
ON-ON-OFF (outdoor LEDs) The system thinks it has lost refrigerant.
Gas leak error.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
ALL indoor LEDs flashing The indoor unit's model option code hasn't been set correctly.
Option code error – all LEDs flash on the indoor unit.		 🟡 Book a service call – this one needs a technician.

Four-way cassette range (outdoor unit E-codes)

Where the code shows: Outdoor unit PCB LED display (red/green/yellow LEDs on the MAIN and INVERTER boards), reported as E-codes..

Tap your code: E201E202E203E221E231E251E320E403E404E416E440E441E458E475E461E462E463E464E465E466E467E468E471E474E484E500E554E556E557
Code What it means What to do
E201 The outdoor unit can't see the number of indoor units it expects.
Indoor/outdoor unit quantity mismatch – usually an addressing or setup issue.		 🟡 Book a service call – this one needs a technician.
E202 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E203 The outdoor unit's two circuit boards (main and inverter) have lost communication with each other.
Main-inverter communication timeout (1 minute).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E221 The outdoor air temperature sensor isn't reading properly.
Outdoor temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
E231 The outdoor coil (condenser) temperature sensor isn't reading properly.
Condenser temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
E251 The compressor discharge temperature sensor isn't reading properly.
Discharge temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
E320 The compressor's overload-protection temperature sensor isn't reading properly.
OLP sensor open/short.		 🟡 Book a service call – this one needs a technician.
E403 The system detected freezing at the outdoor unit and stopped the compressor to protect itself.
Outdoor freeze detection while compressor stopped.		 🟡 Check the return-air filters are clean and nothing is blocking the outdoor unit, then book a service if the code stays.
E404 The outdoor unit shut down to protect itself from overloading.
Outdoor overload protection while compressor stopped.		 🟡 Check nothing is blocking airflow around the outdoor unit, then book a service if the code stays.
E416 The compressor got too hot and the system shut down to prevent damage.
Compressor discharge over-temperature. Can point to low refrigerant.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E440 Heating is locked out because the outdoor temperature is above about 30 degrees C.
Heating-mode ambient lockout, not a component failure.		 🟢 Check the unit is in the mode you actually want. Heating resumes once the outdoor temperature drops back into range – book a service only if it persists in cool weather.
E441 Cooling is locked out because the outdoor temperature is below about -5 degrees C.
Cooling-mode ambient lockout, not a component failure.		 🟢 Check the unit is in the mode you actually want. Cooling resumes once the outdoor temperature rises back into range – book a service only if it persists in warm weather.
E458 Outdoor fan 1 isn't running properly.
Outdoor BLDC fan 1 error.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
E475 Outdoor fan 2 isn't running properly.
Outdoor BLDC fan 2 error.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
E461 The compressor is failing to start.
Inverter compressor starting error.		 🟡 Book a service call – this one needs a technician.
E462 The unit shut down because it drew too much electrical current.
Primary current trip error.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E463 The unit tripped on an electrical over-current and shut itself down.
Over-current trip / PFC over-current error, remark 'check OLP sensor'. Samsung's own manuals also describe E463 as the compressor's overload protector (OLP) overheating and stopping the compressor – the same protective trip worded two ways.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E464 The inverter power module tripped on over-current and shut the unit down.
IPM (IGBT module) over-current.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E465 The compressor overloaded and the unit shut down to protect it.
Compressor overload error as printed; Samsung manuals elsewhere call the same code the compressor V-limit (voltage-limit) error – same protection.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E466 The power supply to the unit went outside its safe voltage range.
DC-link voltage under/over error – often follows a power glitch or brownout.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E467 The outdoor unit can't drive the compressor properly – a compressor wiring or rotation fault.
Compressor wire missing error.		 🟡 Book a service call – this one needs a technician.
E468 A current sensor on the outdoor unit's electronics isn't reading properly.
Current sensor error on the inverter board.		 🟡 Book a service call – this one needs a technician.
E471 The outdoor unit's control board has a memory fault.
Outdoor EEPROM error.		 🟡 Book a service call – this one needs a technician.
E474 A temperature sensor on the inverter electronics isn't reading properly.
IPM (IGBT module) or PFCM temperature sensor error.		 🟡 Book a service call – this one needs a technician.
E484 The power-correction circuit in the outdoor unit overloaded and shut the unit down.
PFC overload error.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E500 The inverter electronics overheated and the unit shut down to protect itself.
IPM over-heated.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E554 The system thinks it has lost refrigerant.
Gas leak error.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
E556 The indoor and outdoor units aren't a matching capacity pairing.
Capacity mismatch between indoor and outdoor unit.		 🟡 Book a service call – this one needs a technician.
E557 The indoor units' option codes don't match each other.
Option code mismatch among indoor units (DPM only).		 🟡 Book a service call – this one needs a technician.

Wired remote controller codes (cassette and ducted systems)

Where the code shows: Wired remote controller screen – a warning icon appears, press the Test button to show the numeric code..

Tap your code: 101102121122128129153201202203221231237251320403404416419422425440441458460461462463464465466467468469471472473474475484485500554556557601602606EA
Code What it means What to do
101 The controller has lost communication with the indoor unit.
Indoor unit communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
102 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor communication timeout (more than 6 bad packets / 60-packet over-data).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
121 The indoor unit's room temperature sensor isn't reading properly.
Indoor temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
122 The indoor coil's temperature sensor isn't reading properly.
Indoor eva-in pipe sensor open/short.		 🟡 Book a service call – this one needs a technician.
128 The indoor coil sensor has come loose from its mounting.
Eva-in sensor disconnection/separation.		 🟡 Book a service call – this one needs a technician.
129 The indoor coil outlet sensor has come loose from its mounting.
Eva-out sensor separation.		 🟡 Book a service call – this one needs a technician.
153 The condensate drain system has flagged high water – the drain safety switch has tripped twice.
Indoor float switch second detection.		 🟡 Book a service call – the drain needs attention before it can run safely.
201 The outdoor unit can't find the indoor unit it expects.
Unit mismatch indoor/outdoor; the second table words it as 'indoor unit is not connected'.		 🟡 Book a service call – this one needs a technician.
202 The indoor and outdoor units have stopped talking to each other.
Indoor/outdoor communication error (1 minute).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
203 The outdoor unit's two circuit boards (main and inverter) have lost communication with each other.
Main-inverter micom communication error (1 minute).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
221 The outdoor air temperature sensor isn't reading properly.
Outdoor temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
231 The outdoor coil (condenser) temperature sensor isn't reading properly.
Condenser temperature sensor error.		 🟡 Book a service call – this one needs a technician.
237 The outdoor coil (condenser) temperature sensor isn't reading properly.
COND temperature sensor open/short – listed separately from 231 in the booklet.		 🟡 Book a service call – this one needs a technician.
251 The compressor discharge temperature sensor isn't reading properly.
Inverter compressor discharge temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
320 The compressor's overload-protection temperature sensor isn't reading properly.
OLP sensor error.		 🟡 Book a service call – this one needs a technician.
403 The system detected freezing at the outdoor unit and stopped the compressor to protect itself.
Outdoor freeze detection while compressor stopped.		 🟡 Check the return-air filters are clean, then book a service if the code stays.
404 The outdoor unit shut down to protect itself from overloading.
Outdoor overload protection while compressor stopped.		 🟡 Check nothing is blocking airflow around the outdoor unit, then book a service if the code stays.
416 The compressor got too hot and the system shut down to prevent damage.
Discharge over-temperature. Can point to low refrigerant.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
419 The refrigerant control valve (EEV) failed to open properly.
EEV open error.		 🟡 Book a service call – this one needs a technician.
422 The refrigerant control valve (EEV) failed to close properly.
EEV close error (printed 'EVV' in the booklet).		 🟡 Book a service call – this one needs a technician.
425 The power cabling to the unit is connected incorrectly.
Power cable miss-connection error.		 🟡 Book a service call – this needs an electrician or technician, not a DIY fix.
440 Heating is locked out because the outdoor temperature is too high.
Heating-mode ambient lockout.		 🟢 Check the mode setting on the controller. Heating resumes when the outdoor temperature drops back into range – book a service only if it persists in cool weather.
441 Cooling is locked out because the outdoor temperature is too low.
Cooling-mode ambient lockout.		 🟢 Check the mode setting on the controller. Cooling resumes when the outdoor temperature rises back into range – book a service only if it persists in warm weather.
458 Outdoor fan 1 isn't running properly.
Outdoor fan 1 error.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
460 The communication wiring between indoor and outdoor units has been connected to the wrong terminal.
Communication wire miss-connection (connected to power terminal).		 🟡 Book a service call – this needs a technician, not a DIY fix.
461 The compressor is failing to start.
Inverter compressor startup error.		 🟡 Book a service call – this one needs a technician.
462 The unit shut down because it drew too much electrical current.
Total current error / PFC over-current error.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
463 The compressor got too hot and the unit shut it down to protect it.
Booklet prints 'OLP Heat Sink Sensor Error', but no Samsung manual uses that wording and the OLP sensor fault is code 320. Official tables define 463 as the compressor OLP over-temperature / over-current trip – corrected accordingly.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
464 The inverter power module tripped on over-current and shut the unit down.
Inverter IPM over-current error.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
465 The outdoor unit is limiting the compressor because voltage went out of range.
Compressor V-limit error; Samsung's CAC manual uses the same wording ('Compressor Vlimit error: E465') and the FJM manual lists 'voltage-limit error of compressor'. The cassette table's 'compressor overload' is the same trip.		 🟡 Book a service call – this one needs a technician.
466 The power supply to the unit went outside its safe voltage range.
DC-link over/low voltage error – the booklet itself suggests restarting after checking power.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
467 The outdoor unit can't drive the compressor properly – a compressor rotation fault.
Inverter compressor rotation error.		 🟡 Book a service call – this one needs a technician.
468 A current sensor on the outdoor unit's electronics isn't reading properly.
Inverter current sensor error.		 🟡 Book a service call – this one needs a technician.
469 The voltage sensor on the outdoor unit's inverter board isn't reading properly.
Inverter DC-link voltage sensor error.		 🟡 Book a service call – this one needs a technician.
471 The outdoor unit's control board has a memory fault.
Inverter OTP / EEPROM read-write error.		 🟡 Book a service call – this one needs a technician.
472 The unit can't read the incoming mains power waveform properly.
AC zero-crossing signal error.		 🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
473 The compressor has seized or locked and won't turn.
Compressor lock error.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
474 The temperature sensor on the inverter heatsink isn't reading properly.
Heat sink sensor error / heatsink temperature over error.		 🟡 Book a service call – this one needs a technician.
475 Outdoor fan 2 isn't running properly.
Outdoor fan 2 error.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
484 The power-correction circuit in the outdoor unit overloaded and shut the unit down.
PFC overload error.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
485 The sensor that measures incoming electrical current isn't reading properly.
Input current sensor error.		 🟡 Book a service call – this one needs a technician.
500 The inverter electronics overheated and the unit shut down to protect itself.
Heat sink over-heat error.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
554 The system thinks it has lost refrigerant.
Gas leak / full refrigerant leakage error.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
556 The outdoor unit's capacity option hasn't been set up correctly.
Outdoor unit capacity setup option error.		 🟡 Book a service call – this one needs a technician.
557 The indoor units' option codes don't match each other.
Option code mismatch among indoor units.		 🟡 Book a service call – this one needs a technician.
601 The wired controller has lost communication with the indoor unit.
Indoor unit to wired remote controller communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
602 The two wired controllers (master and slave) have stopped talking to each other.
Master-slave controller communication error – usually an option-switch setting.		 🟡 Book a service call – this one needs a technician.
606 The wired controller is wired to the wrong communication terminal.
COM1/COM2 cross-installation error.		 🟡 Book a service call – this one needs a technician.
EA The wired controller's COM2 option switch isn't set correctly.
Controller COM2 option setting error (DIP switch).		 🟡 Book a service call – this one needs a technician.

Ducted range (outdoor unit E-codes)

Where the code shows: Outdoor unit PCB LED display (MAIN and INVERTER boards), reported as E-codes..

Tap your code: E201E202E203E221E231E251E320E403E404E416E440E441E458E475E461E462E463E464E465E466E467E468E471E474E484E500E554E556
Code What it means What to do
E201 The outdoor unit can't see the number of indoor units it expects.
Indoor/outdoor unit quantity mismatch.		 🟡 Book a service call – this one needs a technician.
E202 The indoor and outdoor units have stopped talking to each other.
Indoor-outdoor main PCB communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E203 The outdoor unit's two circuit boards (main and inverter) have lost communication with each other.
Main-inverter communication timeout (1 minute).		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E221 The outdoor air temperature sensor isn't reading properly.
Outdoor temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
E231 The outdoor coil (condenser) temperature sensor isn't reading properly.
Condenser temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
E251 The compressor discharge temperature sensor isn't reading properly.
Discharge temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
E320 The compressor's overload-protection temperature sensor isn't reading properly.
OLP sensor open/short.		 🟡 Book a service call – this one needs a technician.
E403 The system detected freezing at the outdoor unit and stopped the compressor to protect itself.
Outdoor freeze detection while compressor stopped.		 🟡 Check the return-air filter is clean and nothing is blocking the outdoor unit, then book a service if the code stays.
E404 The outdoor unit shut down to protect itself from overloading.
Outdoor overload protection while compressor stopped.		 🟡 Check nothing is blocking airflow around the outdoor unit, then book a service if the code stays.
E416 The compressor got too hot and the system shut down to prevent damage.
Compressor discharge over-temperature. Can point to low refrigerant.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E440 Heating is locked out because the outdoor temperature is above about 30 degrees C.
Heating-mode ambient lockout, not a component failure.		 🟢 Check the mode setting. Heating resumes when the outdoor temperature drops back into range – book a service only if it persists in cool weather.
E441 Cooling is locked out because the outdoor temperature is below about -5 degrees C.
Cooling-mode ambient lockout, not a component failure.		 🟢 Check the mode setting. Cooling resumes when the outdoor temperature rises back into range – book a service only if it persists in warm weather.
E458 Outdoor fan 1 isn't running properly.
Outdoor BLDC fan 1 error.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
E475 Outdoor fan 2 isn't running properly.
Outdoor BLDC fan 2 error.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
E461 The compressor is failing to start.
Compressor starting error.		 🟡 Book a service call – this one needs a technician.
E462 The unit shut down because it drew too much electrical current.
Primary current trip error.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E463 The unit tripped on an electrical over-current and shut itself down.
Over-current trip / PFC over-current error, remark 'check OLP sensor'. Samsung's own manuals also describe E463 as the compressor's overload protector (OLP) overheating and stopping the compressor – the same protective trip worded two ways.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E464 The inverter power module tripped on over-current and shut the unit down.
IPM (IGBT module) over-current.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E465 The compressor overloaded and the unit shut down to protect it.
Compressor overload error as printed; Samsung manuals elsewhere call the same code the compressor V-limit (voltage-limit) error – same protection.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E466 The power supply to the unit went outside its safe voltage range.
DC-link voltage under/over error – often follows a power glitch or brownout.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E467 The outdoor unit can't drive the compressor properly – a compressor wiring fault.
Compressor wire missing error.		 🟡 Book a service call – this one needs a technician.
E468 A current sensor on the outdoor unit's electronics isn't reading properly.
Current sensor error on the inverter board.		 🟡 Book a service call – this one needs a technician.
E471 The outdoor unit's control board has a memory fault.
Outdoor EEPROM error.		 🟡 Book a service call – this one needs a technician.
E474 A temperature sensor on the inverter electronics isn't reading properly.
IPM (IGBT module) or PFCM temperature sensor error.		 🟡 Book a service call – this one needs a technician.
E484 The power-correction circuit in the outdoor unit overloaded and shut the unit down.
PFC overload error.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E500 The inverter electronics overheated and the unit shut down to protect itself.
IPM over-heated.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E554 The system thinks it has lost refrigerant.
Gas leak error.		 🔴 Turn the system off at the isolator and call us. Refrigerant work needs a licensed technician.
E556 The indoor and outdoor units aren't a matching capacity pairing.
Capacity mismatch between indoor and outdoor unit.		 🟡 Book a service call – this one needs a technician.

Free Joint Multi (FJM) – indoor unit display codes, MH FVEA / MH FBEA / MH FAEA (AQV heads use the hi-wall split LED patterns)

Where the code shows: Indoor unit display, shown as a split two-part code (e.g. 'E1 01' = E101)..

Tap your code: E101E102E121E122E123E128E129E130E153E154E161E162E163E185E186E201E251E259
Code What it means What to do
E101 The indoor unit has stopped receiving data from the outdoor unit.
Communication error – unable to receive data.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E102 The outdoor unit can't communicate with this indoor unit.
Communication error – outdoor cannot communicate; may involve another indoor unit or the indoor PCB.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E121 The indoor unit's room temperature sensor isn't reading properly.
Room temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
E122 The indoor coil inlet temperature sensor isn't reading properly.
Heat exchanger in sensor open/short.		 🟡 Book a service call – this one needs a technician.
E123 The indoor coil outlet temperature sensor isn't reading properly.
Heat exchanger out sensor open/short.		 🟡 Book a service call – this one needs a technician.
E128 The indoor coil inlet sensor has come loose from its mounting.
Heat exchanger in sensor detached.		 🟡 Book a service call – this one needs a technician.
E129 The indoor coil outlet sensor has come loose from its mounting.
Heat exchanger out sensor detached.		 🟡 Book a service call – this one needs a technician.
E130 Both indoor coil sensors have come loose from their mountings.
Heat exchanger in and out sensors detached.		 🟡 Book a service call – this one needs a technician.
E153 The condensate drain system has flagged high water – the drain safety switch has tripped twice.
Indoor float switch second detection.		 🟡 Book a service call – the drain needs attention before it can run safely.
E154 The indoor fan motor isn't running properly.
Indoor fan motor malfunction.		 🟡 Book a service call – this one needs a technician.
E161 Two or more indoor units are asking for opposite modes at once (some cooling, some heating).
Simultaneous cool/heat operation error – a multi-head system can only run one mode at a time.		 🟢 Set every indoor unit to the same mode (all cooling or all heating), then try again. If the code stays, book a service.
E162 The indoor unit's control board has a memory fault.
Indoor EEPROM error.		 🟡 Book a service call – this one needs a technician.
E163 The indoor unit's model option code hasn't been set correctly.
Option code setting error.		 🟡 Book a service call – this one needs a technician.
E185 The cabling between indoor and outdoor units is connected incorrectly.
Cable miss-wiring between indoor and outdoor unit.		 🟡 Book a service call – this needs a technician, not a DIY fix.
E186 The indoor unit's MPI (plasma/purifier module) has a fault.
MPI error malfunction.		 🟡 Book a service call – this one needs a technician.
E201 The outdoor unit can't see the number of indoor units it expects.
Number of indoor units mismatched – check cabling and outdoor switch settings (technician task).		 🟡 Book a service call – this one needs a technician.
E251 The compressor discharge temperature sensor isn't reading properly.
Compressor discharge sensor open/short.		 🟡 Book a service call – this one needs a technician.
E259 The outdoor unit has a fault – its own display shows the specific code.
Outdoor unit error, see outdoor unit error code.		 🟡 Book a service call – this one needs a technician.

Free Joint Multi (FJM) – outdoor unit PCB display codes

Where the code shows: Outdoor unit PCB display, shown as a split two-part code (e.g. 'E4 61' = E461)..

Tap your code: E101E102E121E122E123E128E129E154E161E162E163E190E199E201E202E203E221E237E246E251E261E320E330E331E332E333E334E335E336E337E338E339E401E404E416E419E422E440E441E458E460E461E462E463E464E465E466E467E468E469E471E472
Code What it means What to do
E101 The indoor unit has stopped receiving data from the outdoor unit.
Communication error – indoor unable to receive data.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E102 The outdoor unit is receiving bad data from an indoor unit.
Outdoor communication error – abnormal data over 60 packets.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E121 An indoor unit's room temperature sensor isn't reading properly.
Indoor room temperature sensor open/short.		 🟡 Book a service call – this one needs a technician.
E122 An indoor coil inlet temperature sensor isn't reading properly.
Indoor heat exchanger in sensor open/short.		 🟡 Book a service call – this one needs a technician.
E123 An indoor coil outlet temperature sensor isn't reading properly.
Indoor heat exchanger out sensor open/short.		 🟡 Book a service call – this one needs a technician.
E128 An indoor coil inlet sensor has come loose from its mounting.
Evaporator pipe-in sensor self-diagnosis error.		 🟡 Book a service call – this one needs a technician.
E129 An indoor coil outlet sensor has come loose from its mounting.
Evaporator pipe-out sensor self-diagnosis error.		 🟡 Book a service call – this one needs a technician.
E154 An indoor fan motor isn't running properly.
Indoor unit fan error.		 🟡 Book a service call – this one needs a technician.
E161 Two or more indoor units are asking for opposite modes at once (some cooling, some heating).
Simultaneous cool/heat operation error.		 🟢 Set every indoor unit to the same mode (all cooling or all heating), then try again. If the code stays, book a service.
E162 An indoor unit's control board has a memory fault.
Indoor unit EEPROM error.		 🟡 Book a service call – this one needs a technician.
E163 An indoor unit's model option code hasn't been set correctly.
Indoor unit EEPROM option error.		 🟡 Book a service call – this one needs a technician.
E190 The system's pipe-check (pairing) routine failed.
Failure of pipe check operation – a commissioning issue.		 🟡 Book a service call – this one needs a technician.
E199 The system was started without completing its pipe-check (pairing) routine.
No pipe check operation done after auto-addressing – a commissioning issue.		 🟡 Book a service call – this one needs a technician.
E201 The outdoor unit can't see the number of indoor units it expects.
Number of indoor units mismatched.		 🟡 Book a service call – this one needs a technician.
E202 The indoor and outdoor units have stopped talking to each other.
Outdoor-indoor communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E203 The outdoor unit's two circuit boards (main and sub) have lost communication with each other.
Outdoor main PCB to sub PCB communication error.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E221 The outdoor air temperature sensor isn't reading properly.
Outside (ambient) temperature sensor short/open. The booklet misprints this as 'E3 21'; official FJM manuals list E221, and the printed voltage thresholds match the E221 row exactly.		 🟡 Book a service call – this one needs a technician.
E237 The outdoor coil (condenser) temperature sensor isn't reading properly.
Condenser temperature sensor short/open.		 🟡 Book a service call – this one needs a technician.
E246 The outdoor coil outlet temperature sensor isn't reading properly.
Condenser-out sensor short/open, self-diagnosis.		 🟡 Book a service call – this one needs a technician.
E251 The compressor discharge temperature sensor isn't reading properly.
Compressor discharge temperature sensor error.		 🟡 Book a service call – this one needs a technician.
E261 The compressor discharge sensor has come loose from its mounting.
Compressor discharge sensor detached, self-diagnosis.		 🟡 Book a service call – this one needs a technician.
E320 The compressor's overload-protection temperature sensor isn't reading properly.
Compressor OLP sensor short/open.		 🟡 Book a service call – this one needs a technician.
E330 The coil inlet sensor for circuit 1 isn't reading properly.
EvaIn1 sensor short/open.		 🟡 Book a service call – this one needs a technician.
E331 The coil inlet sensor for circuit 2 isn't reading properly.
EvaIn2 sensor short/open.		 🟡 Book a service call – this one needs a technician.
E332 The coil inlet sensor for circuit 3 isn't reading properly.
EvaIn3 sensor short/open.		 🟡 Book a service call – this one needs a technician.
E333 The coil inlet sensor for circuit 4 isn't reading properly.
EvaIn4 sensor short/open.		 🟡 Book a service call – this one needs a technician.
E334 The coil inlet sensor for circuit 5 isn't reading properly.
EvaIn5 sensor short/open.		 🟡 Book a service call – this one needs a technician.
E335 The coil outlet sensor for circuit 1 isn't reading properly.
EvaOut1 sensor short/open.		 🟡 Book a service call – this one needs a technician.
E336 The coil outlet sensor for circuit 2 isn't reading properly.
EvaOut2 sensor short/open.		 🟡 Book a service call – this one needs a technician.
E337 The coil outlet sensor for circuit 3 isn't reading properly.
EvaOut3 sensor short/open.		 🟡 Book a service call – this one needs a technician.
E338 The coil outlet sensor for circuit 4 isn't reading properly.
EvaOut4 sensor short/open.		 🟡 Book a service call – this one needs a technician.
E339 The coil outlet sensor for circuit 5 isn't reading properly.
EvaOut5 sensor short/open.		 🟡 Book a service call – this one needs a technician.
E401 The system detected freezing and stopped the compressor to protect itself.
Outdoor unit freezing protection – booklet lists dirty indoor filters and refrigerant charge among the causes.		 🟡 Check the indoor units' filters are clean, then book a service if the code stays.
E404 The outdoor unit shut down to protect itself from overloading.
Outdoor overload safety control – booklet points at pipe length and refrigerant charge.		 🟡 Check nothing is blocking airflow around the outdoor unit, then book a service if the code stays.
E416 The compressor got too hot and the system shut down to prevent damage.
High discharge temperature safety control – booklet points at refrigerant leakage/charge.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E419 A refrigerant control valve (EEV) fault was detected on indoor circuits that are switched off.
Outdoor unit EEV open, detected on stopped indoor units (self diagnosis). Booklet printed 'E4 29'; the FJM Plus service manual lists the self-diagnosis EEV codes as 419 (stopped) and 422 (operating), and the booklet's own controller table has 419 = EEV open. E429 in Samsung literature is a compression-rate error, not EEV – corrected.		 🟡 Book a service call – this one needs a technician.
E422 A refrigerant control valve (EEV) fault was detected on indoor circuits that are running.
Outdoor unit EEV open, detected on operating indoor units (self diagnosis), pairing with E419 for stopped units. Samsung's E422 service guide (Jan 2025) also defines E422 as an EEV open error on FJM/RAC/CAC. Note: the current AJ-series FJM generation reuses E422 for high-pressure blockage control.		 🟡 Book a service call – this one needs a technician.
E440 Heating is locked out because the outdoor temperature is above about 30 degrees C.
Heating-mode ambient lockout, not a component failure.		 🟢 Check the mode setting. Heating resumes when the outdoor temperature drops back into range – book a service only if it persists in cool weather.
E441 Cooling is locked out because the outdoor temperature is below about -10 degrees C.
Cooling-mode ambient lockout, not a component failure.		 🟢 Check the mode setting. Cooling resumes when the outdoor temperature rises back into range – book a service only if it persists in warm weather.
E458 The outdoor fan isn't running properly.
Outdoor fan error.		 🟡 Check nothing is blocking the outdoor unit, then book a service if the fault stays.
E460 The communication cable between indoor and outdoor units is connected to the wrong terminal.
Communication cable mismatched between indoor and outdoor unit.		 🟡 Book a service call – this needs a technician, not a DIY fix.
E461 The compressor failed to start after several attempts.
Inverter compressor starting failure (5 attempts).		 🟡 Book a service call – this one needs a technician.
E462 The unit shut the compressor down because it was drawing too much current.
Compressor trip by input current control (PFC over-current).		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E463 The compressor got too hot and the unit shut it down to protect it.
Compressor trip by OLP temperature control. Official FJM manual AC-00261E: 'compressor operation stop due to OLP temperature control'.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E464 The unit shut down because it drew too much electrical current.
Over-current error.		 🔴 Turn the system off at the isolator and call us – don't keep running it.
E465 The outdoor unit is limiting the compressor because voltage went out of range.
Compressor V-limit (voltage-limit) error per official FJM manual AC-00261E. Samsung's CAC tables label the same code 'compressor overload' – same protective trip.		 🟡 Book a service call – this one needs a technician.
E466 The power supply to the unit went outside its safe voltage range.
DC-link voltage error (under 150V / over 410V) – often follows a power glitch or brownout.		 🟢 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.
E467 The compressor isn't rotating the way the controller expects.
Compressor rotation error.		 🟡 Book a service call – this one needs a technician.
E468 A current sensor on the outdoor unit's electronics isn't reading properly.
Current sensor error.		 🟡 Book a service call – this one needs a technician.
E469 The voltage sensor on the outdoor unit's inverter board isn't reading properly.
DC-link voltage sensor error.		 🟡 Book a service call – this one needs a technician.
E471 The outdoor unit's control board has a memory fault.
OTP error.		 🟡 Book a service call – this one needs a technician.
E472 The unit can't read the incoming mains power waveform properly.
Inverter micom zero-crossing error.		 🟡 Turn the system off at the isolator, wait 20-30 minutes, then turn it back on. If the code returns, book a service.

Code still showing after a reset? Mention the code and your system type when you book and our office can line up the right technician and likely parts before we arrive.

Book a service  or call (02) 4760 0100 (24-hour line, Penrith & Blue Mountains).

Codes vary between models and generations, and manufacturers revise them. This guide is compiled from official service documentation and checked by Ample Air, but it is general information, not a diagnosis. Refrigerant and electrical work must be carried out by licensed technicians. Ample Air, ARC licences AU12976 & AU15788. Last verified August 2026.