When your ActronAir 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.
Aurora (SWB) wall-hung split
Where the code shows: Code on the indoor unit display; operation and timer lamps flash a matching count.
| Code | What it means | What to do |
|---|---|---|
| E0 | The indoor unit's control board has lost its stored settings. Indoor unit EEPROM parameter error. Operation lamp flashes once. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E1 | The indoor and outdoor units have lost communication with each other. Indoor-outdoor communication error, common after a blackout or power glitch. Operation lamp flashes twice. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E3 | The indoor fan isn't running at the speed it should. Indoor fan speed out of control. Operation lamp flashes 4 times. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E4 | The room temperature sensor isn't reading properly. Indoor room temperature sensor T1, open or short circuit. Operation lamp flashes 5 times. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E5 | The indoor coil temperature sensor isn't reading properly. Evaporator coil temperature sensor T2, open or short circuit. Operation lamp flashes 6 times. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC | The system thinks it is losing refrigerant. Refrigerant leakage detection. Operation lamp flashes 7 times. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| F1 | The outdoor air temperature sensor isn't reading properly. Outdoor ambient temperature sensor T4, open or short circuit. Timer lamp on, operation lamp flashes twice. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F2 | The outdoor coil temperature sensor isn't reading properly. Condenser coil temperature sensor T3, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F3 | The compressor outlet temperature sensor isn't reading properly. Compressor discharge temperature sensor T5, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F4 | The outdoor unit's control board has lost its stored settings. Outdoor unit EEPROM parameter error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| F5 | The outdoor fan isn't running at the speed it should. Outdoor fan speed out of control. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| P0 | The outdoor unit's power module has shut down to protect itself. IPM malfunction or IGBT over-strong current protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P1 | The incoming power voltage went too high or too low. Over-voltage or under-voltage protection. Can follow grid brownouts or surges. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P2 | The compressor got too hot and shut itself down. High temperature protection of compressor top. Applies to SWB52C and SWB70C models only. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P4 | The electronics that drive the compressor have reported a fault. Inverter compressor drive error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| CP | The unit has been switched off through its remote on/off connection. Remote On/Off terminal is open circuit. Usually relates to an installer-fitted external switch. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
Serene (WRC / WRE) wall-hung split
Where the code shows: Code on the indoor unit display; operation and timer lamps flash a matching count.
| Code | What it means | What to do |
|---|---|---|
| E0 | The indoor unit's control board has lost its stored settings. Indoor unit EEPROM parameter error. Operation lamp flashes once. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E1 | The indoor and outdoor units have lost communication with each other. Indoor-outdoor communication error, common after a blackout or power glitch. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E3 | The indoor fan isn't running at the speed it should. Indoor fan speed out of control. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E4 | The room temperature sensor isn't reading properly. Indoor room temperature sensor T1, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E5 | The indoor coil temperature sensor isn't reading properly. Evaporator coil temperature sensor T2, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC | The system thinks it is losing refrigerant. Refrigerant leakage detection. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| F0 | The unit shut down because it was drawing too much current. Overload current protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F1 | The outdoor air temperature sensor isn't reading properly. Outdoor ambient temperature sensor T4, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F2 | The outdoor coil temperature sensor isn't reading properly. Condenser coil temperature sensor T3, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F3 | The compressor outlet temperature sensor isn't reading properly. Compressor discharge temperature sensor T5, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F4 | The outdoor unit's control board has lost its stored settings. Outdoor unit EEPROM parameter error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| F5 | The outdoor fan isn't running at the speed it should. Outdoor fan speed out of control. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| P0 | The outdoor unit's power module has shut down to protect itself. IPM malfunction or IGBT over-strong current protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P1 | The incoming power voltage went too high or too low. Over-voltage or under-voltage protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P2 | The power module or the compressor got too hot and the unit shut down to protect itself. High temperature protection of IPM module or compressor top. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P4 | The electronics that drive the compressor have reported a fault. Inverter compressor drive error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| CP | The unit has been switched off through its remote on/off connection. Remote On/Off terminal is open circuit. 2024 table only; not listed for Serene in 2018. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
Cascade (URC / CRE) split system, R-410A
Where the code shows: Indoor unit display and lamp flashes; J-codes and duplicates also on the outdoor unit board.
| Code | What it means | What to do |
|---|---|---|
| E0 | The indoor unit's control board has lost its stored settings. Indoor unit EEPROM malfunction. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E1 | The indoor and outdoor units have lost communication with each other. Indoor-outdoor communication error, common after a blackout or power glitch. Also shown on the outdoor board. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E3 | The indoor fan isn't running at the speed it should. Indoor fan speed out of control. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E4 | The room temperature sensor isn't reading properly. Indoor room temperature sensor T1, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E5 | The indoor coil temperature sensor isn't reading properly. Evaporator coil temperature sensor T2, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC | The system thinks it is losing refrigerant. Refrigerant leakage detection. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| EE | The unit can't clear its condensate water properly and the water level alarm has tripped. Water level arm (float/level switch) malfunction. |
🟡 Switch the unit off so water can't overflow, and book a service. |
| E8 | The two units of a twin system have lost communication with each other. Master-slave communication error, twin systems only. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E9 | Another indoor unit on this twin system has a fault. Check the other indoor unit's display for its own code. Twin systems only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F0 | The unit shut down because it was drawing too much current. Over-current protection (some units). The outdoor board also uses F0 for overcurrent protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F1 | The outdoor air temperature sensor isn't reading properly. Outdoor ambient temperature sensor T4, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F2 | The outdoor coil temperature sensor isn't reading properly. Condenser coil temperature sensor T3, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F3 | The compressor outlet temperature sensor isn't reading properly. Compressor discharge temperature sensor T5, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F4 | The outdoor unit's control board has lost its stored settings. Outdoor unit EEPROM malfunction (some units). |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| F5 | The outdoor fan isn't running at the speed it should. Outdoor fan speed malfunction. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| F6 | The indoor coil outlet temperature sensor isn't reading properly. T2B sensor, open or short circuit (free-match indoor units). |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F7 | The cassette's auto-lifting panel and the unit have lost communication. Communication error between auto-lifting panel and slim cassette (source misprints 'sim cassette'). |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F8 | The cassette's auto-lifting panel has a fault. Slim cassettes with an auto-lifting panel only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F9 | The cassette's auto-lifting panel hasn't closed properly. Slim cassettes with an auto-lifting panel only. |
🟡 Check nothing is caught in or under the panel, then power-cycle at the isolator. If the code returns, book a service. |
| P0 | The outdoor unit's power module has shut down to protect itself. IPM module malfunction/protection. Same code on indoor display and outdoor board. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P1 | The drive's internal DC voltage went too high or too low. DC voltage too high/low protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P2 | The compressor got too hot and shut itself down. Top of compressor high temperature protection. Indoor display only. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P3 | It's too cold outside for the unit to run safely, so it has protected itself. Low ambient temperature protection (outdoor board wording: ultra-low ambient). |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P4 | The electronics that drive the compressor have reported a fault. Indoor table: inverter compressor drive protection. Outdoor table: compressor rotor position protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P6 | The compressor's supply voltage went outside its safe range. Compressor voltage protection. Indoor display only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P7 | A temperature sensor inside the outdoor unit's drive electronics is faulty. Outdoor IGBT sensor faulty. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| J0 | The indoor coil got too hot and the unit protected itself. Evaporator high temperature protection. Outdoor board display. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| J1 | The outdoor coil got too hot and the unit protected itself. Condenser high temperature protection. Outdoor board display. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| J2 | The compressor is running much hotter than it should. High discharge temperature protection. Outdoor board display. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| J3 | A power-conditioning module in the outdoor unit has shut down to protect itself. PFC (power factor correction) module protection. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| J4 | Two control chips inside the outdoor unit have stopped talking to each other. Communication error between outdoor main chip and compressor driver chip. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| J5 | System pressure went too high and the safety cut in. High pressure protection. Outdoor board display. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| J6 | System pressure went too low and the safety cut in. This can point to low refrigerant. Low pressure protection. Outdoor board display. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| J8 | The incoming power voltage went outside the unit's safe range. AC power input voltage protection. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Cascade R-32 (URC / CRC) split system
Where the code shows: Indoor unit display; operation and timer lamps flash a matching count.
Tap your code: EH00 / EH0AEL01EH03EH60EH61EL0CEH0bEH0EEC53EC52EC54EC56EC51EC07PC00PC01PC02PC04PC03EC0DEHbAEH3AEH3b
| Code | What it means | What to do |
|---|---|---|
| EH00 / EH0A | The indoor unit's control board has lost its stored settings. Indoor unit EEPROM parameter error. Operation lamp flashes once. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| EL01 | The indoor and outdoor units have lost communication with each other. Indoor-outdoor communication error, common after a blackout or power glitch. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| EH03 | The indoor fan isn't running at the speed it should. Indoor fan speed outside normal range (some models). |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| EH60 | The room temperature sensor isn't reading properly. Indoor room temperature sensor T1, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EH61 | The indoor coil temperature sensor isn't reading properly. Evaporator coil temperature sensor T2, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EL0C | The system thinks it is losing refrigerant. Refrigerant leakage detection (some models). |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| EH0b | Two control chips inside the indoor unit have stopped talking to each other. Communication error between the two indoor chips. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EH0E | The unit can't clear its condensate water properly and the water level alarm has tripped. Water-level alarm malfunction. |
🟡 Switch the unit off so water can't overflow, and book a service. |
| EC53 | The outdoor air temperature sensor isn't reading properly. Outdoor ambient temperature sensor T4, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC52 | The outdoor coil temperature sensor isn't reading properly. Condenser coil temperature sensor T3, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC54 | The compressor outlet temperature sensor isn't reading properly. Compressor discharge temperature sensor TP, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC56 | The indoor coil outlet temperature sensor isn't reading properly. T2B sensor, open or short circuit (free-match indoor units). |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC51 | The outdoor unit's control board has lost its stored settings. Outdoor unit EEPROM parameter error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| EC07 | The outdoor fan isn't running at the speed it should. Outdoor fan speed outside normal range (some models). |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| PC00 | The outdoor unit's power module has shut down to protect itself. IPM malfunction or IGBT over-strong current protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| PC01 | The incoming power voltage went too high or too low. Over-voltage or under-voltage protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| PC02 | The compressor or its power module got too hot and the unit shut down to protect itself. Top-of-compressor or IPM high temperature protection. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| PC04 | The electronics that drive the compressor have reported a fault. Inverter compressor drive error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| PC03 | System pressure went too high or too low and the safety cut in. High or low pressure protection (some models). |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| EC0D | The outdoor unit has a fault. Outdoor unit malfunction. Check the outdoor board for its own code. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EHbA | The external fan module and the indoor unit have lost communication. Communication malfunction between external fan module and indoor unit. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| EH3A | The external fan module's internal voltage is too low. External fan DC bus voltage too low protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EH3b | The external fan module's internal voltage is too high. External fan DC bus voltage too high fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Ultra Slim (URC / LRE) split ducted, R-410A
Where the code shows: Indoor unit display and lamp flashes; J-codes and duplicates also on the outdoor unit board.
| Code | What it means | What to do |
|---|---|---|
| E0 | The indoor unit's control board has lost its stored settings. Indoor unit EEPROM malfunction. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E1 | The indoor and outdoor units have lost communication with each other. Indoor-outdoor communication error, common after a blackout or power glitch. Also shown on the outdoor board. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E3 | The indoor fan isn't running at the speed it should. Indoor fan speed out of control. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E4 | The room temperature sensor isn't reading properly. Indoor room temperature sensor T1, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E5 | The indoor coil temperature sensor isn't reading properly. Evaporator coil temperature sensor T2, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC | The system thinks it is losing refrigerant. Refrigerant leakage detection. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| EE | The unit can't clear its condensate water properly and the water level alarm has tripped. Water level arm (float/level switch) malfunction. |
🟡 Switch the unit off so water can't overflow, and book a service. |
| E8 | The two units of a twin system have lost communication with each other. Master-slave communication error, twin systems only. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E9 | Another indoor unit on this twin system has a fault. Check the other indoor unit's display for its own code. Twin systems only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F0 | The unit shut down because it was drawing too much current. Over-current protection (some units). The outdoor board also uses F0 for overcurrent protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F1 | The outdoor air temperature sensor isn't reading properly. Outdoor ambient temperature sensor T4, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F2 | The outdoor coil temperature sensor isn't reading properly. Condenser coil temperature sensor T3, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F3 | The compressor outlet temperature sensor isn't reading properly. Compressor discharge temperature sensor T5, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F4 | The outdoor unit's control board has lost its stored settings. Outdoor unit EEPROM malfunction (some units). |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| F5 | The outdoor fan isn't running at the speed it should. Outdoor fan speed malfunction. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| F6 | The indoor coil outlet temperature sensor isn't reading properly. T2B sensor, open or short circuit (free-match indoor units). |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P0 | The outdoor unit's power module has shut down to protect itself. IPM module malfunction/protection. Same code on indoor display and outdoor board. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P1 | The drive's internal DC voltage went too high or too low. DC voltage too high/low protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P2 | The compressor got too hot and shut itself down. Top of compressor high temperature protection. Indoor display only. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P3 | It's too cold outside for the unit to run safely, so it has protected itself. Low ambient temperature protection (outdoor board wording: ultra-low ambient). |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P4 | The electronics that drive the compressor have reported a fault. Indoor table: inverter compressor drive protection. Outdoor table: compressor rotor position protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P6 | The compressor's supply voltage went outside its safe range. Compressor voltage protection. Indoor display only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P7 | A temperature sensor inside the outdoor unit's drive electronics is faulty. Outdoor IGBT sensor faulty. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| J0 | The indoor coil got too hot and the unit protected itself. Evaporator high temperature protection. Outdoor board display. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| J1 | The outdoor coil got too hot and the unit protected itself. Condenser high temperature protection. Outdoor board display. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| J2 | The compressor is running much hotter than it should. High discharge temperature protection. Outdoor board display. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| J3 | A power-conditioning module in the outdoor unit has shut down to protect itself. PFC (power factor correction) module protection. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| J4 | Two control chips inside the outdoor unit have stopped talking to each other. Communication error between outdoor main chip and compressor driver chip. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| J5 | System pressure went too high and the safety cut in. High pressure protection. Outdoor board display. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| J6 | System pressure went too low and the safety cut in. This can point to low refrigerant. Low pressure protection. Outdoor board display. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| J8 | The incoming power voltage went outside the unit's safe range. AC power input voltage protection. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Ultra Slim R-32 (URC / LRE / LRC) split ducted
Where the code shows: Indoor unit display; separate code set on the outdoor unit board (marked in each row).
Tap your code: EH00 / EH0AEL01EH03EH60EH61EL0CEH0bEH0EEC53EC52EC54EC56EC51EC07PC00PC01PC02PC04PC03EC0DEHbAEH3AEH3bE1F0F1F2F3F4F5P0P1P2P4J0J1J2J3J4J5J6P7J8LP
| Code | What it means | What to do |
|---|---|---|
| EH00 / EH0A | The indoor unit's control board has lost its stored settings. Indoor unit EEPROM parameter error. Operation lamp flashes once. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| EL01 | The indoor and outdoor units have lost communication with each other. Indoor-outdoor communication error, common after a blackout or power glitch. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| EH03 | The indoor fan isn't running at the speed it should. Indoor fan speed outside normal range (some models). |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| EH60 | The room temperature sensor isn't reading properly. Indoor room temperature sensor T1, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EH61 | The indoor coil temperature sensor isn't reading properly. Evaporator coil temperature sensor T2, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EL0C | The system thinks it is losing refrigerant. Refrigerant leakage detection (some models). |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| EH0b | Two control chips inside the indoor unit have stopped talking to each other. Communication error between the two indoor chips. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EH0E | The unit can't clear its condensate water properly and the water level alarm has tripped. Water-level alarm malfunction. |
🟡 Switch the unit off so water can't overflow, and book a service. |
| EC53 | The outdoor air temperature sensor isn't reading properly. Outdoor ambient temperature sensor T4, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC52 | The outdoor coil temperature sensor isn't reading properly. Condenser coil temperature sensor T3, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC54 | The compressor outlet temperature sensor isn't reading properly. Compressor discharge temperature sensor TP, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC56 | The indoor coil outlet temperature sensor isn't reading properly. T2B sensor, open or short circuit (free-match indoor units). |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC51 | The outdoor unit's control board has lost its stored settings. Outdoor unit EEPROM parameter error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| EC07 | The outdoor fan isn't running at the speed it should. Outdoor fan speed outside normal range (some models). |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| PC00 | The outdoor unit's power module has shut down to protect itself. IPM malfunction or IGBT over-strong current protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| PC01 | The incoming power voltage went too high or too low. Over-voltage or under-voltage protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| PC02 | The compressor or its power module got too hot and the unit shut down to protect itself. Top-of-compressor or IPM high temperature protection. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| PC04 | The electronics that drive the compressor have reported a fault. Inverter compressor drive error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| PC03 | System pressure went too high or too low and the safety cut in. High or low pressure protection (some models). |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| EC0D | The outdoor unit has a fault. Outdoor unit malfunction. Check the outdoor board for its own code. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EHbA | The external fan module and the indoor unit have lost communication. Communication malfunction between external fan module and indoor unit. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| EH3A | The external fan module's internal voltage is too low. External fan DC bus voltage too low protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EH3b | The external fan module's internal voltage is too high. External fan DC bus voltage too high fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E1 | The indoor and outdoor units have lost communication with each other. Outdoor board display. Indoor-outdoor communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| F0 | The outdoor unit shut down because it was drawing too much current. Outdoor overcurrent protection. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F1 | The outdoor air temperature sensor isn't reading properly. Outdoor ambient temperature sensor T4, open or short circuit. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F2 | The outdoor coil temperature sensor isn't reading properly. Condenser coil temperature sensor T3, open or short circuit. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F3 | The compressor outlet temperature sensor isn't reading properly. Compressor discharge temperature sensor TP, open or short circuit. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F4 | The outdoor unit's control board has lost its stored settings. Outdoor EEPROM malfunction. Outdoor board display. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| F5 | The outdoor fan isn't running at the speed it should. Outdoor fan speed out of control. Outdoor board display. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| P0 | The outdoor unit's power module has shut down to protect itself. IPM module protection. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P1 | The incoming power voltage went too high or too low. Over-voltage or under-voltage protection. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P2 | The compressor got too hot and shut itself down. Top temperature protection of compressor. Outdoor board display. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P4 | The electronics that drive the compressor have reported a fault. Inverter compressor drive error. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| J0 | The indoor coil got too hot and the unit protected itself. High temperature protection of evaporator. Outdoor board display. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| J1 | The outdoor coil got too hot and the unit protected itself. High temperature protection of condenser. Outdoor board display. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| J2 | The compressor is running much hotter than it should. Compressor discharge temperature protection. Outdoor board display. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| J3 | A power-conditioning module in the outdoor unit has shut down to protect itself. PFC module protection. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| J4 | Two boards inside the outdoor unit have stopped talking to each other. Communication malfunction between IPM board and outdoor main board. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| J5 | System pressure went too high and the safety cut in. High pressure protection. Outdoor board display. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| J6 | System pressure went too low and the safety cut in. This can point to low refrigerant. Low pressure protection. Outdoor board display. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P7 | The drive electronics temperature sensor isn't reading properly. IGBT temperature sensor TH, open or short circuit. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| J8 | The incoming power voltage went outside the unit's safe range. AC power input voltage protection. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| LP | It's too cold outside for the unit to run safely, so it has protected itself. Low ambient temperature protection. Outdoor board display. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Multi-split indoor units (MRE / BRE)
Where the code shows: Indoor unit display; operation and timer lamps flash a matching count. Same letters mean different things on the outdoor unit – check the right list..
| Code | What it means | What to do |
|---|---|---|
| CP | The unit has been switched off by a remote switch. Off by remote switch (installer-fitted external control). |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E0 | The indoor unit's control board has lost its stored settings. Indoor unit EEPROM parameter error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E1 | The indoor and outdoor units have lost communication with each other. Indoor-outdoor communication error, common after a blackout or power glitch. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E3 | The indoor fan isn't running at the speed it should. Indoor fan speed malfunction. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E4 | The room temperature sensor isn't reading properly. Indoor room temperature sensor T1 malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E5 | The indoor coil temperature sensor isn't reading properly. Evaporator coil temperature sensor T2 malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E7 | The unit's display panel and its main control board have stopped talking to each other. Communication error between indoor PCB and display PCB. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| EE | The unit can't clear its condensate water properly and the water level alarm has tripped. Water-level alarm malfunction. Cassette and ducted indoor types only. |
🟡 Switch the unit off so water can't overflow, and book a service. |
| F1 | The outdoor air temperature sensor isn't reading properly. Outdoor ambient temperature sensor T4 malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F2 | The outdoor coil temperature sensor isn't reading properly. Condenser coil temperature sensor T3 malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F3 | The compressor outlet temperature sensor isn't reading properly. Compressor discharge temperature sensor T5 malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F4 | The outdoor unit's control board has lost its stored settings. Outdoor unit EEPROM parameter error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| F5 | The outdoor fan isn't running at the speed it should. Outdoor fan speed malfunction. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| F6 | The indoor coil outlet pipe sensor isn't reading properly. Indoor coil outlet pipe sensor malfunction; the sensor sits at the outdoor unit's low pressure valve. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P0 | The outdoor unit's power module has shut down to protect itself. Inverter module (IPM) malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P1 | The incoming power voltage went too high or too low. Over-voltage or under-voltage protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P4 | The electronics that drive the compressor have reported a fault. Compressor drive malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P5 | Two indoor units are asking for opposite modes (one heating, one cooling), which a multi system can't do at once. Indoor unit mode conflict. |
🟢 Set every indoor unit to the same mode (all cooling or all heating) at the controllers. If the code stays after that, power-cycle at the isolator, then book a service if it returns. |
Multi-split outdoor unit (MRC)
Where the code shows: Outdoor unit LED display. Same letters mean different things on the indoor units – check the right list..
| Code | What it means | What to do |
|---|---|---|
| E0 | The outdoor unit's control board has lost its stored settings. Outdoor unit EEPROM parameter error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E2 | The indoor and outdoor units have lost communication with each other. Indoor-outdoor communication malfunction. Per the 2017 troubleshooting guide this code does not self-clear. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E3 | Two boards inside the outdoor unit have stopped talking to each other. Communication malfunction between IPM board and outdoor main control board. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E4 | One of the outdoor unit's temperature sensors isn't reading properly. Covers coil sensor T3, ambient sensor T4, compressor discharge sensor T5 and indoor coil outlet pipe sensor T2B. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E5 | The incoming power voltage went too high or too low. Over-voltage or under-voltage protection. Often follows supply problems; the unit restarts once power is normal. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E6 | A power-conditioning module in the outdoor unit has shut down to protect itself. PFC module protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E8 | The outdoor fan isn't running at the speed it should. Outdoor fan speed malfunction. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| F1 | The coil outlet sensor for indoor unit A isn't reading properly. Indoor unit A coil outlet temperature sensor malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F2 | The coil outlet sensor for indoor unit B isn't reading properly. Indoor unit B coil outlet temperature sensor malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F3 | The coil outlet sensor for indoor unit C isn't reading properly. Indoor unit C coil outlet temperature sensor malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F4 | The coil outlet sensor for indoor unit D isn't reading properly. Indoor unit D coil outlet temperature sensor malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F5 | The coil outlet sensor for indoor unit E isn't reading properly. Indoor unit E coil outlet temperature sensor malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P1 | System pressure went too high and the safety cut in. High pressure protection. MRC-100AS-4, MRC-110AS-5 and MRC-135AS-5 only. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| P2 | System pressure went too low and the safety cut in. This can point to low refrigerant. Low pressure protection. MRC-100AS-4, MRC-110AS-5 and MRC-135AS-5 only. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P3 | The outdoor unit shut down because it was drawing too much current. Current overload protection. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| P4 | The compressor is running much hotter than it should. This can point to low refrigerant. Compressor discharge temperature protection. 2017 guide: trips when discharge exceeds 115 degrees C; refrigerant leakage is a listed cause. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P5 | The outdoor coil got too hot and the unit protected itself. Condenser high temperature protection. 2017 guide: trips above 65 degrees C pipe temperature; dirty coil or blocked airflow are listed causes. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| P6 | The outdoor unit's power module has shut down to protect itself. Inverter module (IPM) protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
WC-02 wired wall controller
Where the code shows: WC-02 controller screen.
| Code | What it means | What to do |
|---|---|---|
| E0 | There's a problem with the order or presence of the incoming power phases. Phase sequence error or phase malfunction. Three-phase supply issue; needs an electrician or technician. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E1 | The indoor and outdoor units have lost communication with each other. Indoor-outdoor communication malfunction. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E2 | The room temperature sensor isn't reading properly. T1 sensor malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E3 | The indoor coil temperature sensor isn't reading properly. T2A sensor malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E4 | The indoor coil outlet temperature sensor isn't reading properly. T2B sensor malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E6 | The controller's electrical timing check has failed. Zero check (zero-cross detection) malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E7 | The indoor unit's control board has lost its stored settings. Indoor EEPROM malfunction (source misprints 'EERROM'). |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E8 | The fan controller isn't responding properly. Fan controller out of control. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E9 | The main control board and the display have stopped talking to each other. Communication malfunction between main PCB and display board. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| EA | The compressor is overloaded. Compressor overload; source notes '(4 times)'. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| EB | The outdoor unit's power module has a fault. IPM module malfunction (source misprints 'IPM mould'). |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EC | The air-cleaning function has a fault. Air clean malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| ED | The outdoor unit has shut down on one of its protections. Outdoor malfunction protection. Check the outdoor unit for its own code. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| EE | The condensate tray is full and the unit has stopped to avoid overflow. Full-water malfunction. |
🟡 Switch the unit off so water can't overflow, and book a service. |
| EF | The system has a fault it can't name on this display. Other fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| F0 | The wired controller and the indoor unit have lost communication. Communication error between wired controller and indoor unit. 2024 edition only. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| F1 | The cassette's drop-down fascia panel hasn't closed properly. Elevating fascia panel not closed. 2024 edition only. |
🟡 Check nothing is caught in or under the panel, then power-cycle at the isolator. If the code returns, book a service. |
| P0 | The indoor coil went outside its safe temperature range and the unit protected itself. Evaporator temperature protection. A dirty filter or blocked vents are common causes. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| P1 | The unit is running its defrost or anti-cold-air mode. This is normal, not a fault. Anti-cold-air or defrost mode indicator. |
🟢 Nothing to do. This is normal operation, not a fault. If it never clears, power-cycle at the isolator and book a service if it persists. |
| P2 | The outdoor coil got too hot and the unit protected itself. Condenser temperature protection. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| P3 | The compressor got too hot and shut itself down. Compressor temperature protection. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P4 | The compressor's outlet pipe got too hot and the unit protected itself. Discharge pipe temperature protection. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P5 | System pressure went too high and the safety cut in. Discharge high pressure protection. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| P6 | System pressure went too low and the safety cut in. This can point to low refrigerant. Discharge low pressure protection. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| P7 | The incoming power voltage went too high. Over-voltage protection. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| P8 | The compressor is overloaded. Compressor overload protection. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| PF | There's a fault elsewhere in the system. Other fault; check the indoor or outdoor unit for its own code. (2018 edition lists P9-PE as unused reserve codes.) |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Classic (SRE* / SRA / SRG) split ducted
Where the code shows: LM7 or LM24 wall controller; single-digit codes on the outdoor CPU LED. *SRE applies to SRE091C/SRG091E only..
| Code | What it means | What to do |
|---|---|---|
| COOL + LOW flashing | The indoor coil is getting too cold, so the unit has dropped to low capacity to stop ice forming. Anti-freeze protection mode (low capacity mode), flashing for 30 seconds on the LM7/LM24 wall controller. Dirty filters or closed vents are the classic cause. |
🟢 Check the return-air filter is clean and all vents and grilles are open, then power-cycle at the isolator. If it keeps happening, book a service. |
| HEAT + HIGH flashing | The unit is getting too hot in heating and has protected itself. Overheat safety protection, flashing for 30 seconds on the wall controller. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E6 | The compressor is running much hotter than it should. The doc links this to being low on refrigerant. Fault: discharge high temperature (low on refrigerant). Outdoor CPU shows 6. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E7 | The outdoor coil sensor isn't reading properly. Outdoor coil sensor open or short circuit. Outdoor CPU shows 7. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E9 | A pressure safety has tripped, or there's a power phase problem. High or low pressure / phase error. Outdoor CPU shows 9. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E5 | The indoor and outdoor units have lost communication with each other. Communication error between outdoor and indoor. Wall controller only. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E3 | The room temperature sensor isn't reading properly. Room sensor(s) open or short circuit. Wall controller only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E4 | The indoor coil sensor isn't reading properly. Indoor coil-in sensor open or short circuit. Wall controller only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Classic 2 (CRA / CCA / EVA / EAA / EFA) split ducted
Where the code shows: LR7-1 wall controller and outdoor CPU display.
| Code | What it means | What to do |
|---|---|---|
| COOL + LOW flashing | The indoor coil is getting too cold, so the unit has protected itself against icing up. Anti-freeze protection mode, flashing 30 seconds on the LR7-1 wall controller. |
🟢 Check the return-air filter is clean and all vents and grilles are open, then power-cycle at the isolator. If it keeps happening, book a service. |
| HEAT + HIGH flashing | The unit is getting too hot in heating and has protected itself. Overheat protection mode, flashing 30 seconds on the wall controller. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E01 | The indoor fan isn't running at the speed the system asked for. Indoor fan RPM feedback error. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E03 | The room temperature sensor isn't reading properly. Room temperature error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E04 | The indoor coil sensor isn't reading properly. Indoor coil sensor error. Wall controller only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E07 | The outdoor coil sensor isn't reading properly. Outdoor coil sensor error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E09 | The low-pressure safety switch has tripped. This often points to low refrigerant. LP switch tripped. May not show on the wall control until it has happened several times. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E11 | The high-pressure safety switch has tripped. HP switch tripped. May not show on the wall control until it has happened several times. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| E51 | The indoor and outdoor units have lost communication with each other. IDU-ODU communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E52 | The indoor unit and the wall controller have lost communication. IDU-wall controller communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E55 | The connection to the building management system has dropped out. BMS-ODU communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E56 | The system can't find a master wall controller. No master wall controller detected. Can appear after power interruptions; if it stays, it needs a technician. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
ESP Digital (SRD / SRV) split ducted
Where the code shows: LM7 or LM24 wall controller; single-digit codes on the outdoor CPU LED.
| Code | What it means | What to do |
|---|---|---|
| LOW flashing | The unit has dropped to low capacity to protect itself against overheating or icing up. Overheat or anti-freeze protection mode (low capacity mode), LOW speed flashing 30 seconds on the wall controller. Outdoor CPU shows 4. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E6 | The compressor is running much hotter than it should. The doc links this to being low on refrigerant. Fault: discharge high temperature (low on refrigerant). Outdoor CPU shows 6. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E7 | The outdoor coil sensor isn't reading properly. Outdoor coil sensor open or short circuit. Outdoor CPU shows 7. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E8 | The outdoor discharge sensor isn't reading properly. Outdoor discharge sensor open or short circuit. Outdoor CPU shows 8. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E9 | A pressure safety has tripped, or there's a power phase problem. High or low pressure / phase error. Three-phase models only. Outdoor CPU shows 9. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E5 | The indoor and outdoor units have lost communication with each other. Communication error between outdoor and indoor. Wall controller only. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E3 | The room temperature sensor isn't reading properly. Room sensor(s) open or short circuit. Wall controller only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E4 | The indoor coil inlet sensor isn't reading properly. Indoor coil-in sensor open or short circuit. Wall controller only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E2 | The indoor coil outlet sensor isn't reading properly. Indoor coil-out sensor open or short circuit. Wall controller only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
ESP Platinum (CRV / ERV / ARV / FRV / ERM) split ducted
Where the code shows: LM7/LM24 wall controller and outdoor CPU 7-segment display; a subset shows on the LM-ZC zone controller.
Tap your code: E3E4E5E6E7E8E9E10E11E12E14E15E17E18E19E22E23E25E26E27E28E29E30E31E32 / E33E34E35E36E37E38E39E40E41E99
| Code | What it means | What to do |
|---|---|---|
| E3 | The room temperature sensor isn't reading properly. Room sensor error, open or short circuit. Wall and zone controllers. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E4 | The indoor coil inlet sensor isn't reading properly. Indoor coil inlet sensor error, open or short circuit. Wall controller only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E5 | The indoor and outdoor units have lost communication with each other. IDU-ODU communication error. Outdoor CPU shows E05. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E6 | The compressor is running much hotter than it should. This can point to low refrigerant. High discharge temperature; trips when discharge exceeds 138 degrees C. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E7 | The outdoor coil sensor isn't reading properly. Outdoor coil sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E8 | The outdoor discharge sensor isn't reading properly. Outdoor discharge sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E9 | The low-pressure safety switch has tripped. This often points to low refrigerant. LP tripped. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E10 | The low-pressure sensor isn't reading properly. LP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E11 | The high-pressure safety switch has tripped. HP tripped. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| E12 | The high-pressure sensor isn't reading properly. HP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E14 | Pressure on the outdoor coil side is unusually low. Condenser pressure low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E15 | The outdoor unit and its inverter drive have lost communication. VSD communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E17 | One of the outdoor unit's peripheral devices has a fault. Peripherals error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E18 | The suction temperature sensor isn't reading properly. In EEV module, suction temp sensor is open. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E19 | The suction temperature sensor isn't reading properly. In EEV module, suction temp sensor is shorted. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E22 | The outdoor air temperature sensor has failed, so the unit is running in a limited safe mode. Ambient sensor failure (open/short circuit), safe mode. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E23 | A control board for the refrigerant valve has lost communication, so the unit is running in a limited safe mode. EEV board communication failure, safe mode. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E25 | The outdoor temperature reading isn't updating. Ambient temperature not updated (status). |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E26 | The inverter drive has detected too much current. VSD over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E27 | The inverter drive has detected voltage that is too high. VSD over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E28 | The inverter drive is running too hot. VSD temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E29 | The incoming power voltage is too low for the inverter drive. Low supply voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E30 | The inverter drive has locked itself out after repeated faults. VSD trip lock. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E31 | The inverter drive has an internal fault. VSD internal error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E32 / E33 | A pressure safety tripped based on the drive's pressure sensors. Envelope protection: HP/LP trip error via VSD pressure sensors. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E34 | The unit has wound itself back because the inverter drive is running hot. Derating: high VSD temperature. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E35 | The unit has wound itself back because suction pressure is low. Derating: low suction pressure. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E36 | The unit has wound itself back because condenser pressure is low. Derating: low condenser pressure. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E37 | The unit has wound itself back because condenser pressure is high. Derating: high condenser pressure. Note: the wall controller also briefly shows E37 as a status during indoor coil pre-heat after defrost, which is normal. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E38 | The unit has wound itself back to its output power limit. Derating: output power limit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E39 | A defrost cycle took too long and timed out. Defrosting timed out. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E40 | The inverter drive is restarting too often. VSD restarting too frequently. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E41 | The inverter drive's internal DC voltage is too low. VSD DC link voltage low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E99 | The system is operating outside its safe pressure/temperature envelope. Envelope protection. Listed in the Platinum service manual (Sec. 15); not shown in the 2024 Platinum table but present in the QUE table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
ESP QUE Platinum (CRQ / ERQ / ARV / FRQ) split ducted
Where the code shows: QT-1000 master controller (status bar and Tech Menu) and outdoor CPU display.
Tap your code: E03E04E05E06E07E08E09E10E11E12E13E14E15E17E18 / E19E22E23E25E26E27E28E29E30E31E32 / E33E34E35 / E36 / E37E38E39E40E41E42E43E44E45E47E50E51E52E53E60E62E63E66E67E69E70E71E72E74E75E76E77E78E80E81E82E83E84E85E86E87E88E89E90E91E92E99
| Code | What it means | What to do |
|---|---|---|
| E03 | The room temperature sensor isn't reading properly. Room sensor error, open or short circuit. Single-phase: shown in controller Tech Menu as E3. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E04 | The indoor coil sensor isn't reading properly. Single-phase: indoor coil inlet sensor (Tech Menu E4). Three-phase table lists indoor coil out sensor error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E05 | The indoor and outdoor units have lost communication with each other. Shown as E05 on the outdoor CPU and as E51 in the controller Tech Menu. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E06 | The compressor is running much hotter than it should. This can point to low refrigerant. High discharge temperature; trips when discharge exceeds 138 degrees C. Tech Menu E6. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E07 | The outdoor coil sensor isn't reading properly. Outdoor coil sensor error, open or short circuit. Tech Menu E7. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E08 | The outdoor discharge sensor isn't reading properly. Outdoor discharge sensor error, open or short circuit. Tech Menu E8. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E09 | The low-pressure safety switch has tripped. This often points to low refrigerant. LP tripped. Tech Menu E9. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E10 | The low-pressure sensor isn't reading properly. LP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E11 | The high-pressure safety switch has tripped. HP tripped. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| E12 | The high-pressure sensor isn't reading properly. HP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E13 | The outdoor unit's inverter drive has reported a fault. Three-phase table: VSD HSP connector (jumper pin missing) / other drive errors. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E14 | Pressure on the outdoor coil side is unusually low. Condenser pressure low. Single-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E15 | The outdoor unit and its inverter drive have lost communication. VSD communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E17 | One of the outdoor unit's peripheral devices has a fault. Peripherals error. Single-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E18 / E19 | The suction temperature sensor isn't reading properly. Single-phase: in EEV module, suction temp sensor open (E18) or shorted (E19). Three-phase lists only E18, abnormal reading value. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E22 | The outdoor air temperature sensor has failed; single-phase units drop to a limited safe mode. Ambient sensor failure, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E23 | A control board for the refrigerant valve has lost communication, so the unit is running in a limited safe mode. EEV board communication failure, safe mode. Single-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E25 | The outdoor temperature reading isn't updating. Ambient temperature not updated (status). Single-phase table. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E26 | The inverter drive has detected too much current. Over current (three-phase table: alarm-over current). |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E27 | The inverter drive has detected voltage that is too high. Over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E28 | The inverter drive is running too hot. VSD/drive temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E29 | The incoming power voltage is too low for the inverter drive. Low supply voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E30 | The inverter drive has locked itself out after repeated faults. Trip lock. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E31 | The inverter drive has an internal fault. VSD internal error. Single-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E32 / E33 | A pressure safety tripped based on the drive's pressure sensors. Envelope protection: HP/LP trip error via VSD pressure sensors. Single-phase table. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E34 | The unit has wound itself back because the inverter drive is running hot. Derating: high VSD temperature. Single-phase table. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E35 / E36 / E37 | The unit has wound itself back because system pressure is outside its comfort zone. Derating: low suction (E35), low condenser (E36) or high condenser (E37) pressure. Single-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E38 | The unit has wound itself back to its output power limit. Derating: output power limit. Single-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E39 | A defrost cycle took too long and timed out. Defrosting timed out. Single-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E40 | The inverter drive is restarting too often. VSD restarting too frequently. Single-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E41 | The inverter drive's internal DC voltage is too low. DC link voltage low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E42 | The system is operating outside its safe pressure/temperature envelope. Envelope protection error. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E43 | The system is operating outside its safe pressure/temperature envelope. Envelope protection error. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E44 | The system is operating outside its safe pressure/temperature envelope. Envelope protection error. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E45 | The system is operating outside its safe pressure/temperature envelope. Envelope protection error. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E47 | The compressor hit its torque limit. Compressor torque limit error. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E50 | The outdoor unit's control board has a configuration problem. Outdoor board configuration error. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E51 | The indoor and outdoor units have lost communication with each other. IDU-ODU communication error. Three-phase table; on single-phase the outdoor CPU shows E05 for this. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E52 | The indoor unit and the master controller have lost communication. Shown in the controller Tech Menu. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E53 | The indoor unit and its zone module have lost communication. IDU VAV/VAQ zone module communication error. Shown in the controller Tech Menu. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E60 | The drive measured too much current going to the compressor. VSD compressor phase over current. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E62 | The drive's internal DC voltage went too high. VSD DC bus over voltage. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E63 | The drive's internal DC voltage went too low. VSD DC bus under voltage. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E66 | The incoming power phases are unbalanced, or a phase has dropped out. VSD AC voltage imbalance / AC input loss of phase. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E67 | The drive's power electronics reported an internal switching fault. VSD inverter de-saturation. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E69 | Part of the drive's power electronics is overheating. VSD PFC-IGBT over temperature. Three-phase table. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E70 | The drive lost track of the compressor motor's rotation. VSD loss of rotor / lost rotor position. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E71 | The compressor motor's temperature sensor is faulty. Motor thermistor fault. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E72 | A startup relay inside the drive isn't closing properly. VSD precharge relay open. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E74 | The drive measured too much current going to the compressor. VSD compressor phase over current. Three-phase table lists E74 as compressor phase over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E75 | The drive repeatedly had to wind back compressor current and eventually shut down. VSD compressor phase current foldback timeout. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E76 | The drive repeatedly had to wind back for module temperature and eventually shut down. VSD power module temperature foldback timeout. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E77 | The drive repeatedly had to wind back input current and eventually shut down. VSD AC input current foldback timeout. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E78 | The drive's automatic configuration handshake timed out. VSD auto config communication timeout. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E80 | The compressor motor is running too hot. VSD motor temperature high. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E81 | A circuit board in the drive is running too hot. VSD board temperature high. Three-phase table. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E82 | The drive's power module is running too hot. VSD power module temperature high. Three-phase table. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E83 | Part of the drive's power electronics is running too hot. VSD PFC-IGBT temperature high. Three-phase table. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E84 | Two circuit boards inside the drive have stopped talking to each other. Communication error in VSD between DSP and PFC. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E85 | Two circuit boards inside the drive have stopped talking to each other. Communication error in VSD between comms processor and DSP. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E86 | Current to the compressor is unbalanced across its phases. VSD compressor phase current imbalance. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E87 | Current inside the drive's power-correction circuit is unbalanced. VSD 3-phase PFC current imbalance. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E88 | The drive's electronics or memory have an internal fault. VSD micro-electronic or EEPROM error. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E89 | The compressor motor ran faster than allowed. VSD motor over speed. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E90 | The drive doesn't recognise the compressor it's connected to. VSD compressor model configuration error. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E91 | Temperatures inside the drive's inverter section are unbalanced. VSD inverter temperature imbalance. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E92 | Temperatures inside the drive's power-correction section are unbalanced. VSD PFC temperature imbalance. Three-phase table. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E99 | The system is operating outside its safe pressure/temperature envelope. Envelope protection. Shown in the controller Tech Menu. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Advance (CRV / EVV / EAA / EFV) split ducted, R-410A Uno and R-32 Uno Pro boards
Where the code shows: NEO or LR7-1/LC7-2 wall controller and outdoor unit CPU (same code on all three).
Tap your code: E01E03E04E06E07E08E09E10E11E12E13E15E18E22E26E27E28E29E30E41E42E43E44E45E47E50E51E52E55E56E60E61E62E63E64E65E66E67E68E69E70E71E72E73E74E75E76E77E78E79E80E81E82E83E84E85E86E87E88E89E90E91E92E93E94E95E96E97E98E99E100E101E102E103E104
| Code | What it means | What to do |
|---|---|---|
| E01 | The indoor fan isn't running at the speed the system asked for. Indoor fan RPM feedback error. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E03 | The room temperature sensor isn't reading properly. Indoor room temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E04 | The indoor coil's inlet temperature sensor isn't reading properly. Indoor coil-in temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E06 | The compressor is running much hotter than it should. This can point to low refrigerant. High discharge temperature. Trips when discharge temperature exceeds 120 degrees C. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E07 | The outdoor coil's temperature sensor isn't reading properly. Outdoor coil temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E08 | The compressor outlet temperature sensor isn't reading properly. Discharge temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E09 | The low-pressure safety switch has tripped. This often points to low refrigerant. LP switch tripped. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E10 | The low-pressure sensor isn't reading properly. LP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E11 | The high-pressure safety switch has tripped. HP switch tripped. Blocked outdoor airflow is one common cause. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| E12 | The high-pressure sensor isn't reading properly. HP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E13 | The outdoor unit's inverter drive has reported a fault. Other drive errors. On Advance R-410A (Uno board) E13 can also mean the VSD HSP connector jumper pin is missing. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E15 | The outdoor unit and its inverter drive have lost communication. ODU-VSD communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E18 | The suction line temperature sensor isn't reading properly. Suction temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E22 | The outdoor air temperature sensor isn't reading properly. Ambient temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E26 | The inverter drive has detected too much incoming current. VSD supply/input over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E27 | The inverter drive has detected incoming voltage that is too high. VSD supply/input over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E28 | The inverter drive is running too hot. VSD temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E29 | The incoming power voltage is too low for the inverter drive. VSD low supply voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E30 | The inverter drive has locked itself out after repeated faults. VSD trip lock. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E41 | The inverter drive's internal DC voltage is too low. VSD DC link voltage low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E42 | The system is running with abnormally low suction pressure. This can point to low refrigerant. Envelope protection error: extreme low evaporating pressure. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E43 | The compressor is working outside its safe range (compression ratio too high). Envelope protection error: high compression ratio. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E44 | Pressure on the outdoor coil side is too high for safe operation. Envelope protection error: high condensing pressure. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E45 | The compressor is working outside its safe range (compression ratio too low). Envelope protection error: low compression ratio. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E47 | The compressor hit its torque limit. Compressor torque limit error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E50 | The outdoor unit's control board has a configuration problem. Outdoor board configuration error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E51 | The indoor and outdoor units have lost communication with each other. Outdoor-indoor communication error, common after a blackout or power glitch. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E52 | The indoor unit and the wall controller have lost communication. Indoor unit to wall controller communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E55 | The connection to the building management system has dropped out. BMS to outdoor unit communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E56 | The system can't find a master wall controller. No master wall controller detected. Can appear after power interruptions; if it stays, it needs a technician. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E60 | The drive measured too much current going to the compressor. VSD compressor phase over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E61 | The drive has lost one of the compressor's electrical phases. VSD compressor loss of phase. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E62 | The drive's internal DC voltage went too high. VSD DC bus over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E63 | The drive's internal DC voltage went too low. VSD DC bus under voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E64 | The drive lost track of the compressor motor's rotation. VSD loss of rotor / lost rotor position. Listed as VSD compressor loss of rotor. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E65 | A current sensor inside the drive (phase U) is faulty. VSD compressor U phase current sensor fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E66 | The incoming power phases are unbalanced, or a phase has dropped out. VSD AC voltage imbalance / AC input loss of phase. Advance R-410A (Uno board) only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E67 | The drive's power electronics reported an internal switching fault. VSD inverter de-saturation. Advance R-410A (Uno board) only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E68 | A current sensor inside the drive (phase V) is faulty. VSD compressor V phase current sensor fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E69 | Part of the drive's power electronics is overheating. VSD PFC-IGBT over temperature. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E70 | The drive lost track of the compressor motor's rotation. VSD loss of rotor / lost rotor position. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E71 | The compressor motor's temperature sensor is faulty. VSD motor temperature sensor error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E72 | A startup relay inside the drive isn't closing properly. VSD precharge relay open. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E73 | A current sensor inside the drive (phase W) is faulty. VSD compressor W phase current sensor fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E74 | The drive's power electronics measured too much current. VSD IGBT over current. Source adds: choke wiring or failure. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E75 | The drive repeatedly had to wind back compressor current and eventually shut down. VSD compressor phase current foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E76 | The drive repeatedly had to wind back for module temperature and eventually shut down. VSD power module temperature foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E77 | The drive repeatedly had to wind back input current and eventually shut down. VSD AC input current foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E78 | Part of the drive's power electronics is reading abnormally cold. VSD PFC-IGBT temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E79 | The drive's power module reported a hardware over-current. VSD IPM desat protection / compressor hardware over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E80 | The compressor motor is running too hot. VSD motor temperature high. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E81 | A circuit board in the drive is running too hot. VSD board temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E82 | The drive's power module is running too hot. VSD power module temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E83 | Part of the drive's power electronics is running too hot. VSD PFC-IGBT temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E84 | Two circuit boards inside the drive have stopped talking to each other. Communication error in VSD between DSP and PFC. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E85 | Two circuit boards inside the drive have stopped talking to each other. Communication error in VSD between comms processor and DSP. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E86 | Current to the compressor is unbalanced across its phases. VSD compressor phase current imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E87 | Current inside the drive's power-correction circuit is unbalanced. VSD 3-phase PFC current imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E88 | The drive's electronics or memory have an internal fault. VSD micro-electronic or EEPROM error. Advance R-32 (Uno Pro board) only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E89 | The compressor motor ran faster than allowed. VSD motor over speed. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E90 | The drive doesn't recognise the compressor it's connected to. VSD compressor model configuration error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E91 | Temperatures inside the drive's inverter section are unbalanced. VSD inverter temperature imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E92 | Temperatures inside the drive's power-correction section are unbalanced. VSD PFC temperature imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E93 | The compressor motor is reading abnormally cold. VSD motor temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E94 | A circuit board in the drive is reading abnormally cold. VSD board temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E95 | The drive's power module is reading abnormally cold, or its sensor is faulty. VSD power module temperature low, or sensor open/short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E96 | Part of the drive's power electronics is reading abnormally cold. VSD PFC-IGBT temperature low. Listed as VSD PFC-IGBT temp low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E97 | An internal measurement circuit in the drive has failed. VSD comms ADC failure. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E98 | A current-measuring circuit in the drive is faulty. VSD PFC / input current sensor fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E99 | The compressor is overloaded. VSD compressor overload. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E100 | The drive's power-correction circuit measured too much current (hardware trip). VSD PFC hardware over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E101 | The drive's power-correction circuit measured too much current (software trip). VSD PFC software over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E102 | The drive's power-correction circuit voltage went too high. VSD PFC over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E103 | The drive's power module is reading abnormally cold, or its sensor circuit is open. VSD power module temperature low or sensor open fault. Advance R-32 (Uno Pro board) only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E104 | The drive shut down after hitting its fault limit too many times. VSD fault limit lockout. Advance R-32 (Uno Pro board) only. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Aires (CRS / EVA) split ducted
Where the code shows: NEO or LR7-1/LC7-2 wall controller and outdoor unit CPU (same code on all three).
Tap your code: E01E03E04E06E07E08E09E10E11E12E13E15E18E22E26E27E28E29E30E41E42E43E44E45E47E50E51E52E55E56E60E61E62E63E65E69E70E71E72E73E74E75E76E77E78E79E80E81E82E83E84E85E88E90E91E92E93E94E95E96E97E98E99E100E101E102E103E104
| Code | What it means | What to do |
|---|---|---|
| E01 | The indoor fan isn't running at the speed the system asked for. Indoor fan RPM feedback error. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E03 | The room temperature sensor isn't reading properly. Indoor room temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E04 | The indoor coil's inlet temperature sensor isn't reading properly. Indoor coil-in temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E06 | The compressor is running much hotter than it should. This can point to low refrigerant. High discharge temperature. Trips when discharge temperature exceeds 138 degrees C. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E07 | The outdoor coil's temperature sensor isn't reading properly. Outdoor coil temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E08 | The compressor outlet temperature sensor isn't reading properly. Discharge temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E09 | The low-pressure safety switch has tripped. This often points to low refrigerant. LP switch tripped. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E10 | The low-pressure sensor isn't reading properly. LP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E11 | The high-pressure safety switch has tripped. HP switch tripped. Blocked outdoor airflow is one common cause. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| E12 | The high-pressure sensor isn't reading properly. HP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E13 | The outdoor unit's inverter drive has reported a fault. Other drive errors. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E15 | The outdoor unit and its inverter drive have lost communication. ODU-VSD communication error. Listed as VSD-ODU Modbus communication lost. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E18 | The suction line temperature sensor isn't reading properly. Suction temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E22 | The outdoor air temperature sensor isn't reading properly. Ambient temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E26 | The inverter drive has detected too much incoming current. VSD supply/input over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E27 | The inverter drive has detected incoming voltage that is too high. VSD supply/input over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E28 | The drive's power module is running too hot. VSD power module temperature high. Listed as VSD power module over temp. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E29 | The incoming power voltage is too low for the inverter drive. VSD low supply voltage. Listed as VSD input under voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E30 | The inverter drive has locked itself out after repeated faults. VSD trip lock. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E41 | The inverter drive's internal DC voltage is too low. VSD DC link voltage low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E42 | The system is running with abnormally low suction pressure. This can point to low refrigerant. Envelope protection error: extreme low evaporating pressure. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E43 | The compressor is working outside its safe range (compression ratio too high). Envelope protection error: high compression ratio. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E44 | Pressure on the outdoor coil side is too high for safe operation. Envelope protection error: high condensing pressure. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E45 | The compressor is working outside its safe range (compression ratio too low). Envelope protection error: low compression ratio. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E47 | The compressor hit its torque limit. Compressor torque limit error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E50 | The outdoor unit's control board has a configuration problem. Outdoor board configuration error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E51 | The indoor and outdoor units have lost communication with each other. Outdoor-indoor communication error, common after a blackout or power glitch. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E52 | The indoor unit and the wall controller have lost communication. Indoor unit to wall controller communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E55 | The connection to the building management system has dropped out. BMS to outdoor unit communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E56 | The system can't find a master wall controller. No master wall controller detected. Can appear after power interruptions; if it stays, it needs a technician. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E60 | The drive measured too much current going to the compressor. VSD compressor phase over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E61 | The drive has lost one of the compressor's electrical phases. VSD compressor loss of phase. Listed as VSD compressor loss of output phase. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E62 | The drive's internal DC voltage went too high. VSD DC bus over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E63 | The drive's internal DC voltage went too low. VSD DC bus under voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E65 | The drive has lost one of the compressor's electrical phases. VSD compressor loss of phase. Listed as compressor phase loss fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E69 | Part of the drive's power electronics is overheating. VSD PFC-IGBT over temperature. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E70 | The drive lost track of the compressor motor's rotation. VSD loss of rotor / lost rotor position. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E71 | The compressor motor's temperature sensor is faulty. VSD motor temperature sensor error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E72 | A startup relay inside the drive isn't closing properly. VSD precharge relay open. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E73 | A current sensor inside the drive (phase W) is faulty. VSD compressor W phase current sensor fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E74 | The drive's power electronics measured too much current. VSD IGBT over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E75 | The drive repeatedly had to wind back compressor current and eventually shut down. VSD compressor phase current foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E76 | The drive repeatedly had to wind back for module temperature and eventually shut down. VSD power module temperature foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E77 | The drive repeatedly had to wind back input current and eventually shut down. VSD AC input current foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E78 | Part of the drive's power electronics is reading abnormally cold. VSD PFC-IGBT temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E79 | The drive's power module reported a hardware over-current. VSD IPM desat protection / compressor hardware over current. Listed as VSD IPM modular over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E80 | The compressor motor is running too hot. VSD motor temperature high. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E81 | A circuit board in the drive is running too hot. VSD board temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E82 | The drive's power module is running too hot. VSD power module temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E83 | Part of the drive's power electronics is running too hot. VSD PFC-IGBT temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E84 | Two circuit boards inside the drive have stopped talking to each other. Communication error in VSD between DSP and PFC. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E85 | Two circuit boards inside the drive have stopped talking to each other. Communication error in VSD between comms processor and DSP. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E88 | The drive's electronics or memory have an internal fault. VSD micro-electronic or EEPROM error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E90 | The drive doesn't recognise the compressor it's connected to. VSD compressor model configuration error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E91 | Temperatures inside the drive's inverter section are unbalanced. VSD inverter temperature imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E92 | Temperatures inside the drive's power-correction section are unbalanced. VSD PFC temperature imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E93 | The compressor motor is reading abnormally cold. VSD motor temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E94 | A circuit board in the drive is reading abnormally cold. VSD board temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E95 | The drive's power module is reading abnormally cold, or its sensor is faulty. VSD power module temperature low, or sensor open/short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E96 | The temperature-sensing circuit for the drive's power-correction module is faulty. VSD PFC module temperature sensing circuit malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E97 | A control chip in the drive keeps resetting. VSD IC reset malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E98 | A current-sensing circuit in the drive is faulty. VSD current sensing circuit malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E99 | The drive reported an unspecified internal fault. VSD other malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E100 | The drive's charging circuit is faulty. VSD charging circuit malfunction. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E101 | The drive's power-correction circuit measured too much current (software trip). VSD PFC software over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E102 | The drive's power-correction circuit voltage went too high. VSD PFC over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E103 | The drive's power module is reading abnormally cold, or its sensor circuit is open. VSD power module temperature low or sensor open fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E104 | The drive shut down after hitting its fault limit too many times. VSD fault limit lockout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Commercial Split (SCA / SCG) and Package (PCA / PCG)
Where the code shows: C7 wall controller; single-digit codes on the outdoor CPU LED.
| Code | What it means | What to do |
|---|---|---|
| E7 | The outdoor coil sensor isn't reading properly. Open circuit (outdoor CPU shows 7) or short circuit (outdoor CPU shows 8). |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E9 | A pressure safety has tripped. High or low pressure fault. Outdoor CPU shows 9. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E5 | The indoor and outdoor units have lost communication with each other. Communication error between outdoor and indoor. C7 wall controller only. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
Variable Commercial (PRV) package unit
Where the code shows: NEO or LR7-1/LC7-2 wall controller and outdoor unit CPU.
Tap your code: E01E03E04E06E07E08E09E10E11E12E13E15E18E22E26E27E28E29E30E41E42E43E44E45E47E50E51E52E55E56E60E62E63E69E70E71E72E74E75E76E77E78E80E81E82E83E84E85E86E87E88E89E90E91E92E93E94E95E96E97E103E104
| Code | What it means | What to do |
|---|---|---|
| E01 | The indoor fan isn't running at the speed the system asked for. Indoor fan RPM feedback error. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E03 | The room temperature sensor isn't reading properly. Indoor room temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E04 | The indoor coil's inlet temperature sensor isn't reading properly. Indoor coil-in temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E06 | The compressor is running much hotter than it should. This can point to low refrigerant. High discharge temperature. Trips when discharge temperature exceeds 120 degrees C. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E07 | The outdoor coil's temperature sensor isn't reading properly. Outdoor coil temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E08 | The compressor outlet temperature sensor isn't reading properly. Discharge temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E09 | The low-pressure safety switch has tripped. This often points to low refrigerant. LP switch tripped. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E10 | The low-pressure sensor isn't reading properly. LP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E11 | The high-pressure safety switch has tripped. HP switch tripped. Blocked outdoor airflow is one common cause. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| E12 | The high-pressure sensor isn't reading properly. HP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E13 | The outdoor unit's inverter drive has reported a fault. Other drive errors. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E15 | The outdoor unit and its inverter drive have lost communication. ODU-VSD communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E18 | The suction line temperature sensor isn't reading properly. Suction temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E22 | The outdoor air temperature sensor isn't reading properly. Ambient temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E26 | The inverter drive has detected too much incoming current. VSD supply/input over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E27 | The inverter drive has detected incoming voltage that is too high. VSD supply/input over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E28 | The inverter drive is running too hot. VSD temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E29 | The incoming power voltage is too low for the inverter drive. VSD low supply voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E30 | The inverter drive has locked itself out after repeated faults. VSD trip lock. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E41 | The inverter drive's internal DC voltage is too low. VSD DC link voltage low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E42 | The system is running with abnormally low suction pressure. This can point to low refrigerant. Envelope protection error: extreme low evaporating pressure. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E43 | The compressor is working outside its safe range (compression ratio too high). Envelope protection error: high compression ratio. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E44 | Pressure on the outdoor coil side is too high for safe operation. Envelope protection error: high condensing pressure. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E45 | The compressor is working outside its safe range (compression ratio too low). Envelope protection error: low compression ratio. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E47 | The compressor hit its torque limit. Compressor torque limit error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E50 | The outdoor unit's control board has a configuration problem. Outdoor board configuration error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E51 | The indoor and outdoor units have lost communication with each other. Outdoor-indoor communication error, common after a blackout or power glitch. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E52 | The indoor unit and the wall controller have lost communication. Indoor unit to wall controller communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E55 | The connection to the building management system has dropped out. BMS to outdoor unit communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E56 | The system can't find a master wall controller. No master wall controller detected. Can appear after power interruptions; if it stays, it needs a technician. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E60 | The drive measured too much current going to the compressor. VSD compressor phase over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E62 | The drive's internal DC voltage went too high. VSD DC bus over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E63 | The drive's internal DC voltage went too low. VSD DC bus under voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E69 | Part of the drive's power electronics is overheating. VSD PFC-IGBT over temperature. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E70 | The drive lost track of the compressor motor's rotation. VSD loss of rotor / lost rotor position. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E71 | The compressor motor's temperature sensor is faulty. VSD motor temperature sensor error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E72 | A startup relay inside the drive isn't closing properly. VSD precharge relay open. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E74 | The drive's power electronics measured too much current. VSD IGBT over current. Source adds: choke wiring or failure. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E75 | The drive repeatedly had to wind back compressor current and eventually shut down. VSD compressor phase current foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E76 | The drive repeatedly had to wind back for module temperature and eventually shut down. VSD power module temperature foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E77 | The drive repeatedly had to wind back input current and eventually shut down. VSD AC input current foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E78 | Part of the drive's power electronics is reading abnormally cold. VSD PFC-IGBT temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E80 | The compressor motor is running too hot. VSD motor temperature high. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E81 | A circuit board in the drive is running too hot. VSD board temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E82 | The drive's power module is running too hot. VSD power module temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E83 | Part of the drive's power electronics is running too hot. VSD PFC-IGBT temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E84 | Two circuit boards inside the drive have stopped talking to each other. Communication error in VSD between DSP and PFC. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E85 | Two circuit boards inside the drive have stopped talking to each other. Communication error in VSD between comms processor and DSP. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E86 | Current to the compressor is unbalanced across its phases. VSD compressor phase current imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E87 | Current inside the drive's power-correction circuit is unbalanced. VSD 3-phase PFC current imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E88 | The drive's electronics or memory have an internal fault. VSD micro-electronic or EEPROM error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E89 | The compressor motor ran faster than allowed. VSD motor over speed. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E90 | The drive doesn't recognise the compressor it's connected to. VSD compressor model configuration error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E91 | Temperatures inside the drive's inverter section are unbalanced. VSD inverter temperature imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E92 | Temperatures inside the drive's power-correction section are unbalanced. VSD PFC temperature imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E93 | The compressor motor is reading abnormally cold. VSD motor temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E94 | A circuit board in the drive is reading abnormally cold. VSD board temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E95 | The drive's power module is reading abnormally cold, or its sensor is faulty. VSD power module temperature low, or sensor open/short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E96 | Part of the drive's power electronics is reading abnormally cold. VSD PFC-IGBT temperature low. Listed as VSD PFC-IGBT temp low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E97 | An internal measurement circuit in the drive has failed. VSD comms ADC failure. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E103 | The drive's power module is reading abnormally cold, or its sensor circuit is open. VSD power module temperature low or sensor open fault. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E104 | The drive shut down after hitting its fault limit too many times. VSD fault limit lockout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Variable Commercial Split (CRV / EVA) and Package PKV160T-240T
Where the code shows: LC7-2 master control and outdoor unit CPU.
Tap your code: E03E04E06E07E08E09E10E11E12E13E15E18E22E26E27E28E29E30E41E42E43E44E45E47E50E51E53E54E55E56E60E62E63E66E67E69E70E71E72E74E75E76E77E78E80E81E82E83E84E85E86E87E88E89E90E91E92E93E94E95E96E97
| Code | What it means | What to do |
|---|---|---|
| E03 | The room temperature sensor isn't reading properly. Indoor room temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E04 | The indoor coil's inlet temperature sensor isn't reading properly. Indoor coil-in temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E06 | The compressor is running much hotter than it should. This can point to low refrigerant. High discharge temperature. Trips when discharge temperature exceeds 138 degrees C. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E07 | The outdoor coil's temperature sensor isn't reading properly. Outdoor coil temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E08 | The compressor outlet temperature sensor isn't reading properly. Discharge temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E09 | The low-pressure safety switch has tripped. This often points to low refrigerant. LP switch tripped. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E10 | The low-pressure sensor isn't reading properly. LP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E11 | The high-pressure safety switch has tripped. HP switch tripped. Blocked outdoor airflow is one common cause. |
🔴 Switch the system off at the isolator and call us. It's fine to clear anything blocking the outdoor unit while you wait, but leave the system switched off. |
| E12 | The high-pressure sensor isn't reading properly. HP sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E13 | The outdoor unit's inverter drive has reported a fault. Other drive errors. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E15 | The outdoor unit and its inverter drive have lost communication. ODU-VSD communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E18 | The suction line temperature sensor isn't reading properly. Suction temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E22 | The outdoor air temperature sensor isn't reading properly. Ambient temperature sensor error, open or short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E26 | The inverter drive has detected too much incoming current. VSD supply/input over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E27 | The inverter drive has detected incoming voltage that is too high. VSD supply/input over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E28 | The inverter drive is running too hot. VSD temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E29 | The incoming power voltage is too low for the inverter drive. VSD low supply voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E30 | The inverter drive has locked itself out after repeated faults. VSD trip lock. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E41 | The inverter drive's internal DC voltage is too low. VSD DC link voltage low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E42 | The system is running with abnormally low suction pressure. This can point to low refrigerant. Envelope protection error: extreme low evaporating pressure. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| E43 | The compressor is working outside its safe range (compression ratio too high). Envelope protection error: high compression ratio. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E44 | Pressure on the outdoor coil side is too high for safe operation. Envelope protection error: high condensing pressure. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E45 | The compressor is working outside its safe range (compression ratio too low). Envelope protection error: low compression ratio. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E47 | The compressor hit its torque limit. Compressor torque limit error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E50 | The outdoor unit's control board has a configuration problem. Outdoor board configuration error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E51 | The indoor and outdoor units have lost communication with each other. Outdoor-indoor communication error, common after a blackout or power glitch. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E53 | The indoor unit and the wall controller have lost communication. Indoor unit to wall controller communication error. Listed as communication error between indoor and master control. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E54 | The indoor fan isn't running at the speed the system asked for. Indoor fan RPM feedback error. Listed as loss of Modbus packets from the 485 indoor fan for 30 seconds; clears when packets resume. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| E55 | The connection to the building management system has dropped out. BMS to outdoor unit communication error. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E56 | The system can't find a master wall controller. No master wall controller detected. Can appear after power interruptions; if it stays, it needs a technician. |
🟢 Power-cycle at the isolator: switch off, wait 20 to 30 minutes, switch back on. If the code returns, book a service. |
| E60 | The drive measured too much current going to the compressor. VSD compressor phase over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E62 | The drive's internal DC voltage went too high. VSD DC bus over voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E63 | The drive's internal DC voltage went too low. VSD DC bus under voltage. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E66 | The incoming power phases are unbalanced, or a phase has dropped out. VSD AC voltage imbalance / AC input loss of phase. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E67 | The drive's power electronics reported an internal switching fault. VSD inverter de-saturation. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E69 | Part of the drive's power electronics is overheating. VSD PFC-IGBT over temperature. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E70 | The drive lost track of the compressor motor's rotation. VSD loss of rotor / lost rotor position. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E71 | The compressor motor's temperature sensor is faulty. VSD motor temperature sensor error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E72 | A startup relay inside the drive isn't closing properly. VSD precharge relay open. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E74 | The drive measured too much current going to the compressor. VSD compressor phase over current. Listed as VSD compressor phase over current. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E75 | The drive repeatedly had to wind back compressor current and eventually shut down. VSD compressor phase current foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E76 | The drive repeatedly had to wind back for module temperature and eventually shut down. VSD power module temperature foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E77 | The drive repeatedly had to wind back input current and eventually shut down. VSD AC input current foldback timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E78 | The drive's automatic configuration handshake timed out. VSD auto config communication timeout. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E80 | The compressor motor is running too hot. VSD motor temperature high. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E81 | A circuit board in the drive is running too hot. VSD board temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E82 | The drive's power module is running too hot. VSD power module temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E83 | Part of the drive's power electronics is running too hot. VSD PFC-IGBT temperature high. |
🟡 Clear leaves, covers or plants away from the outdoor unit so air can flow freely, then power-cycle at the isolator. If the code returns, book a service. |
| E84 | Two circuit boards inside the drive have stopped talking to each other. Communication error in VSD between DSP and PFC. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E85 | Two circuit boards inside the drive have stopped talking to each other. Communication error in VSD between comms processor and DSP. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E86 | Current to the compressor is unbalanced across its phases. VSD compressor phase current imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E87 | Current inside the drive's power-correction circuit is unbalanced. VSD 3-phase PFC current imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E88 | The drive's electronics or memory have an internal fault. VSD micro-electronic or EEPROM error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E89 | The compressor motor ran faster than allowed. VSD motor over speed. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E90 | The drive doesn't recognise the compressor it's connected to. VSD compressor model configuration error. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E91 | Temperatures inside the drive's inverter section are unbalanced. VSD inverter temperature imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E92 | Temperatures inside the drive's power-correction section are unbalanced. VSD PFC temperature imbalance. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E93 | The compressor motor is reading abnormally cold. VSD motor temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E94 | A circuit board in the drive is reading abnormally cold. VSD board temperature low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E95 | The drive's power module is reading abnormally cold, or its sensor is faulty. VSD power module temperature low, or sensor open/short circuit. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E96 | Part of the drive's power electronics is reading abnormally cold. VSD PFC-IGBT temperature low. Listed as VSD PFC-IGBT temp low. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| E97 | An internal measurement circuit in the drive has failed. VSD comms ADC failure. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
Hercules Package System (PKV1400 / PKV1700 / PKV2000)
Where the code shows: Unit controller alarm list (AL numbers).
Tap your code: AL03AL04AL05AL06AL07AL08AL09AL10AL11AL12AL13AL17AL18AL23 / AL24AL28-AL31AL32-AL35AL210AL211AL141 / AL181
| Code | What it means | What to do |
|---|---|---|
| AL03 | The compressor 1 low-pressure sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a warning in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL04 | The compressor 1 suction temperature sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a warning in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL05 | The compressor 2 low-pressure sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a alarm in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL06 | The compressor 2 suction temperature sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a alarm in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL07 | The compressor 1 high-pressure sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a alarm in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL08 | The compressor 1 outdoor coil temperature sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a alarm in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL09 | The compressor 2 high-pressure sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a alarm in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL10 | The compressor 2 outdoor coil temperature sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a warning in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL11 | The return air temperature sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a warning in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL12 | The outside air temperature sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a warning in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL13 | The supply air temperature sensor isn't reading properly (faulty wiring, or open/short circuit). Classified as a alarm in the source. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL17 | Compressor 1's high/low pressure safety switch has tripped. Trip points: above 4000 kPa or below 300 kPa (PKV1400); above 4502 kPa (PKV1700); above 4000 kPa (PKV2000). |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| AL18 | Compressor 2's high/low pressure safety switch has tripped. Same trip points as AL17 for the matching model. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| AL23 / AL24 | Compressor 1 or 2 is overloaded (drive alarm, high current). Comp 1 / Comp 2 overload alarm. |
🔴 Switch the system off at the isolator and call us. Leave it off until a technician has checked it. |
| AL28-AL31 | One of the supply fans (1-4) has dropped offline. Supply fan device offline, communication loss. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL32-AL35 | One of the outdoor fans (1-4) has dropped offline. Outdoor fan device offline, communication loss. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the technician. |
| AL210 | The supply air filter is dirty and due for cleaning. Supply air filter cleaning notification (warning). |
🟢 Clean or replace the air filter, then clear the notification. If it returns straight away, book a service. |
| AL211 | Airflow from the supply fan is much lower than expected. Supply air pressure below 15 Pa with fan speed above 250 rpm. |
🟡 Check the return-air filter is clean and vents are open, then power-cycle at the isolator. If the code returns, book a service. |
| AL141 / AL181 | One of the inverter drives (VSD 1 / VSD 2) has dropped offline. VSD device offline, communication loss. |
🟡 Book a service. A power-cycle at the isolator (off 20 to 30 minutes) is safe to try in the meantime, but if the code returns leave it for the 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.