LG · Air Conditioner error code
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Guide · Air ConditionerMost PTAC no-cool calls are airflow (filter, coils), a wrong control setting or a failed compressor start component. Rule those out before suspecting the sealed system.
Guide · Air ConditionerPTACs heat with electric strip heat, a heat pump, or both. Heat pump models switch to strip heat in cold weather. Check settings, then the heater element and its limits, then the reversing valve.
Guide · Air ConditionerMost PTAC brands store fault codes that can be shown with a button combination on the control (for example, on GE Zoneline (2019 technical service guide) you hold FAN and the red AUX button together while the unit is OFF, and AUX clears stored faults; other models use other sequences, so use the model's tech sheet). Read the active code, fix the cause, then clear it.
LG · Air Conditioner
CH 09
Indoor board EEPROM error
LG · Air Conditioner
CH 10
Indoor fan motor error
LG · Air Conditioner
CH 12
Indoor middle pipe thermistor open/short
LG · Air Conditioner
CH 21
DC peak / IPM fault (inverter)
LG · Air Conditioner
CH 22
CT2 error: AC input current too high
LG · Air Conditioner
CH 23
DC link voltage too low