If any error occurs in your air conditioner, indoor display shows error codes. Once you nail down the issue you can easily call in a professional, or fix the issue yourself. To help you out we have listed down the most common error codes of Lennox AC.
Indoor Unit Error Display
|E0||EEPROM parameter error|
|E1||Indoor/outdoor units communication protection|
|E2||Zero-crossing signal error|
|E3||Indoor fan speed out of control|
|E5||Open or short circuit of outdoor temperature sensor or outdoor unit EEPROM parameter error|
|E6||Open or short circuit of room or evaporator temperature sensor|
|E7||Outdoor fan speed out of control|
|P0||IBM malfunction or IGBT over-strong current protection|
|P1||Over voltage or too low voltage protection|
|P2||Temperature protection of compressor top|
|P4||Inverter compressor drive error|
Lennox Split AC
If there is an error occurring during the operation of the system, the error code will be displayed on the LCD, as show in Fig.5.1. If multi errors occur at the same time, their codes will be displayed circularly.
|F1||Return air temperature sensor open/ short circuited|
|P6||Drive board communication error|
|F2||Evaporator temperature sensor open/ short circuited|
|H3||Compressor overheating protection|
|b5||Indoor unit liquid valve temperature sensor open/short circuited|
|LP||Indoor and outdoor units unmatched|
|b7||Indoor gas valve temperature sensor open/ short circuited|
|dn||Communication line misconnected or expansion valve error|
|P7||IPM temperature sensor open/short circuited|
|E7||Running mode conflict|
|F3||Outdoor ambient temperature sensor open/ short circuited|
|F4||Outdoor unit condenser mid-tube temperature sensor open/short circuited|
|F5||Discharge temperature sensor open/ short circuited|
|E6||Indoor and outdoor communication error|
|Lc||Compressor startup failure|
|PL||DC bus under-voltage protection......|
|E4||High discharge temperature protection|
|PH||DC bus over-voltage protection|
|U1||Compressor phase current sensing circuit error|
|E5||Whole unit over-current protection|
|HE||Compressor demagnetization protection|
|P5||Over phase current protection|
|P8||IPM Temperature Protection|
|H5||IPM Current protection|
|Ld||Compressor phase loss/reversal protection|
|F0||System charge shortage or blockage protection|
|F8||Frequency restricted/reduced with whole unit current protection|
|PU||Capacitor charging error|
|IPM||Frequency restricted/reduced with|
|E1||High pressure protection|
|F9||Frequency restricted/reduced with high discharge temperature|
|E3||Low pressure protection|
|FH||Frequency restricted/reduced with antifreezing protection|
|F6||Frequency restricted/reduced with overload protection|
|EU||Frequency restricted/reduced with IPM temperature protection|
|PF||Drive board temperature sensor error|
|E9||Indoor unit full water error|
|P9||AC contactor protection|
|PE||Temperature drift protection|
|PP||AC input voltage abnormal|
|Pd||Sensor connection protection|
|U5||Whole unit current sensing circuit error|
|U3||DC bus voltage drop error|
|U7||4-way valve reversing error|
|L3||Outdoor fan 1 error protection|
|LA||Outdoor fan 2 error protection|
|U8||PG motor zero-crossing protection|
Note: In event of any error, please turn off the unit and contact the professionally skilled personnel.
Lennox Air Conditioner Mini Split
Indoor and Outdoor Error Codes
Climatic 50 Roof-Top, Aircoolair & Compactair Version 24
|004||Filters, Clogged up|
|006||Recovery Module, Filters, Clogged up|
|011||Electric heating elements|
|012||High Temperature, Blowing|
|013||Low Temperature, Ambient|
|022||Low Temperature, Blowing|
|023||High Temperature, Ambient|
|051||Recovery Module, Motor failure|
|052||Recovery Module, Wheel failure|
|081||Temperature sensor, Ambient|
|082||Humidity sensor, Ambient|
|083||Temperature probe, Outside|
|084||Humidity sensor, Outside|
|085||Temperature probe, Blower|
|086||Circuit 1, Temperature sensor, Water condenser Outlet|
|087||Circuit 2, Temperature sensor, Water condenser Outlet|
|088||Temperature sensor, return or Mixing air|
|096||Low temperature, Water Condenser|
|097||High temperature, Water Condenser|
Lennox AC Troubleshooting
Please check below items before asking for maintenance.
Phenomenon: Indoor unit can’t receive remote controller’s signal or remote controller has no action.
- Whether remote controller is within the signal receiving range?
- Whether there are obstacles?
- Whether remote controller is pointing at the receiving window?
- Is sensitivity of remote controller low; fuzzy display and no display?
- No display when operating remote controller?
- Fluorescent lamp in room?
- Signal receiving range is 8m.
- Remove obstacles.
- Select proper angle and point the remote controller at the receiving window on indoor unit.
- Check the batteries. If the power of batteries is too low, please replace them.
- Check whether remote controller appears to be damaged. If yes, replace it.
- Take the remote controller close to indoor unit.
Phenomenon: No air emitted from indoor unit
- Air inlet or air outlet of indoor unit is blocked?
- Under heating mode, indoor temperature is reached to set temperature?
- Heating mode is turned on just now?
- Eliminate obstacles.
- After reaching to set temperature, indoor unit will stop blowing out air.
- In order to prevent blowing out cold air, indoor unit will be started after delaying for several minutes, which is a normal phenomenon.
Phenomenon: Air conditioner can’t operate
- Power failure?
- Is plug loose?
- Air switch trips off or fuse is burnt out?
- Wiring has malfunction?
- Unit has restarted immediately after stopping operation?
- Whether the function setting for remote controller is correct?
- Wait until power recovery.
- Reinsert the plug.
- Ask professional to replace air switch or fuse.
- Ask professional to replace it.
- Wait for 3min, and then turn on the unit again.
- Reset the function.
Phenomenon: Mist is emitted from indoor unit’s air outlet
Check items: Indoor temperature and humidity is high?
Solution: Because indoor air is cooled\rapidly. After a while, indoor temperature and humidity will be decrease and mist will disappear.
Phenomenon: Cooling ( heating) effect is not good
- Voltage is too low?
- Filter is dirty?
- Set temperature is in proper range?
- Door and window are open?
- Wait until the voltage resumes normal.
- Clean the filter.
- Adjust temperature to proper range.
- Close door and window.
Phenomenon: Outdoor unit has vapor
Check items: Heating mode is turned on?
Solution: During defrosting under heating mode, it may generate vapor, which is a normal phenomenon.
Phenomenon: ”Water flowing” noise
Check items: Air conditioner is turned on or turned offjust now?
Solution: The noise is the sound of \refrigerant flowing inside the unit, which is a normal phenomenon.
Phenomenon: Cracking noise
Check items: Air conditioner is turned on or turned offjust now?
Solution: This is the sound of frictioh caused by expansion and/or contraction of panel or other parts clue to the change of temperature.
Lennox Air Conditioner Manual PDF
*If you can't find the code you're looking for on our site, please let us know, and we'll update our database as soon as possible.
10 thoughts on “Lennox AC Error Codes”
Error code PC 03 flashing, need fixing?
I saw an error code of dp and df at different times. What should I do? I have a mini split head and outdoor unit.
I have an error code that reads 15 EE. How do I fix or clear it?
Gracias xlos códigos consta base salgo del problema
We have a error 3 what can I do
ı need your help
ı have an inverter mninisplit lennox model lxgıhhmd01815p4
code error f2
what the problem..
Kerr 18000 mini split heat pump.have code P4 what to do.
we have en E6 error message, what should we do?
Can’t find error code H5 on this list