LG Heat Pump Error Code 44

Error code 44 on an LG heat pump indicates that the outdoor unit air temperature sensor has been detected as either open circuit or short circuit. The control board monitors this thermistor's resistance to track outdoor ambient temperature, and the code triggers when the signal falls outside the acceptable range. The system will not operate normally until the fault is resolved.

The heat pump will typically suspend normal operation when error code 44 is active, which is a protective response. Attempting to force the system to run without a valid outdoor air temperature signal could lead to improper compressor or refrigerant cycle operation. It is best to leave the system off and address the sensor fault before resuming use.

If only the sensor connector needs cleaning or reseating, there may be little to no parts cost, though a service call fee typically ranges from $75 to $150. Replacing the outdoor air temperature sensor itself generally costs between $20 and $80 for the part, plus labor. If the outdoor unit PCB is at fault, board replacement can range from $150 to $400 or more depending on the model, plus the cost of the technician's time.

A knowledgeable DIYer can check and reseat the sensor connector at the outdoor PCB, which resolves the fault in some cases. However, accurately diagnosing the sensor using resistance measurements and safely working inside the outdoor unit requires a multimeter and comfort with electrical components. If the sensor or PCB needs replacement, a certified HVAC technician is recommended, especially since the system involves refrigerant and high-voltage components.

A power reset may temporarily clear the error code display, but the fault will return if the underlying sensor or wiring problem has not been corrected. The control board will re-detect the out-of-range signal as soon as it resumes monitoring the outdoor air sensor. A permanent resolution requires repairing or replacing the defective sensor, harness, or connector.