LG Air Conditioner Error Code E442

E442 indicates a refrigerant charging restriction in heating mode triggered when the outdoor air temperature is detected above 15 degrees Celsius. This is a protective function built into the system to prevent improper refrigerant servicing under unsuitable ambient conditions. The outdoor temperature sensor reading should be compared to the actual temperature to confirm whether the restriction is legitimate or sensor-related.

E442 is primarily a service-mode restriction rather than an indication of a dangerous failure, so the unit may continue to operate for general heating or cooling use. However, if a faulty sensor is causing the code, that underlying issue should be addressed to ensure the system is reading operating conditions accurately. Continuing to ignore a sensor fault can lead to inefficient operation or additional faults over time.

A reset may temporarily clear the E442 code, but the fault will return if the underlying condition persists. If outdoor temperatures remain above 15 degrees Celsius during a heating mode service attempt, the restriction will reactivate by design. If a faulty sensor is responsible, the code will recur until the sensor or its wiring is repaired or replaced.

If the actual outdoor temperature is above 15 degrees Celsius, there is no fault to fix since the system is operating correctly. However, if temperatures are below that threshold, checking the outdoor temperature sensor connection and comparing its reading to actual ambient temperature is a reasonable first step. Any work involving refrigerant must be performed by a licensed HVAC technician.

If the fault is caused by the actual outdoor temperature being above 15 degrees Celsius, no repair is needed and there is no cost. If an outdoor temperature sensor replacement is required, parts and labor typically range from around 80 to 250 dollars depending on the model and service rates in your area. A wiring repair would generally fall toward the lower end of that range, while a control board replacement would be on the higher end.