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Lennox appliance error codes
Search 2 Lennox diagnostic guides across 2 appliance types. Start with the appliance category or search the code or symptom directly.
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2 guides found
LennoxAir Conditioner
Code E228
Code E228 indicates the main control board has lost speed feedback or communication with the ECM outdoor condenser fan motor.
LennoxHeat Pump
Code E121
Lennox communicator code E121 triggers when the outdoor unit low pressure switch detects unsafe refrigerant loss or freezing.