Model reference
Lennox XC20-024-230A
Air Conditioner
1 document38 error codes6 service modes
Available documentation
Service Manual
- INSTALLATION AND SERVICE PROCEDURE - Elite Series® XC20 Units77 pg
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Error codes (38)
CodeMeaning
E105The outdoor control has lost communication with either the thermostat or indoor…E120There is a delay in the outdoor unit responding to the system.E124The iComfort Wi-Fi thermostat has lost communication with the outdoor unit for…E125There is a hardware problem with the outdoor control.E131The outdoor unit control parameters are corrupted.E132Internal software error on the outdoor control.E180The outdoor unit ambient temperature sensor has malfunctioned; outdoor unit…E345The 'O' relay on the outdoor board has failedE409Outdoor control secondary voltage is 18VAC or less; after 10 minutes, operation…E410The outdoor unit low pressure switch has closed indicating unit pressure is…E411The low pressure switch has opened 5 times within one hour, locking out the…E412The outdoor unit high pressure switch has opened indicating unit pressure is…E413The high pressure switch has opened 5 times within one hour, locking out the…E416The outdoor coil sensor has malfunctioned (open, shorted, or out of range)…E422Compressor top cap switch exceeding thermal limit.E423The inverter has detected a circuit problem (inverter code 40).E424The liquid line temperature sensor has malfunctioned (open or shorted).E425Outdoor control has increased minimum compressor speed to allow for proper oil…E426Excessive inverter alarmsE427The inverter has detected a DC peak fault condition (55A or higher), causing…E428The inverter has detected a high main input current condition.E429DC link power in inverter does not rise above threshold (180 VDC for 2/3-ton…E430Compressor start failure detected by inverter (inverter code 26).E431PFC detected an over-current condition of 100A (inverter code 27), indicating…E432The inverter has detected a DC link high voltage condition (greater than…E433The inverter has detected a compressor over-current condition (peak phase…E434Outdoor control has lost communications with the inverter for greater than 3…E435Inverter internal error (inverter code 60); outdoor control cycles power to the…E436Inverter heat sink temperature exceeded limit (inverter code 62).E437Heat sink temperature sensor fault has occurredView all 38 error codes
E438The inverter has detected a PFC over current condition caused by a high load…E439Compressor slowdown due to high input current (inverter code 12); input current…E440Heat sink temperature is approaching limit (inverter code 13); compressor speed…E441Compressor slowdown due to high compressor current (inverter code 14)…E442The top cap switch has opened five times within one hour, locking out the…E443Incorrect appliance unit size code selected.E600Compressor has been cycled OFF on utility load shedding.E601Outdoor unit has been cycled OFF on low temperature protection (outdoor temp at…
Service modes (6)
- Diagnostic Mode1
- Display Configuration Mode (Enable coil and liquid line temperature display)1
- Error Code Recall Mode1
- Outdoor Fan Test Mode1
- Pump Down Mode1
- Unit Selection Code Programming1
Full entry steps, exit procedures, and test sequences are available in Max.
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