Haier Air Conditioner Error Code F4

F4 on a Haier air conditioner means the compressor discharge temperature exceeded 110 degrees Celsius, triggering the overheat protection circuit. The system shuts down automatically to prevent compressor damage. The fault is indicated by LED1 on the outdoor unit flashing 8 times. A technician should measure the exhaust temperature sensor on the outdoor unit compressor as the first diagnostic step.

No. The F4 code means the system has already shut down as a safety measure because compressor temperatures reached a dangerous level. Attempting to force the unit to run in this condition risks permanent compressor damage, which is one of the most expensive components to replace. Leave the system off until the root cause has been identified and corrected.

Repair costs vary depending on the root cause. Cleaning the condenser coils is relatively inexpensive, typically in the range of $75 to $150 for a service call. Refrigerant recharge can range from $150 to $400 or more depending on refrigerant type and the amount needed. Replacing a discharge temperature sensor generally falls in the $100 to $250 range for parts and labor, while a condenser fan motor replacement may cost $200 to $500. Compressor replacement, if damage has already occurred, is significantly higher.

Some causes, such as cleaning blocked condenser coils or clearing debris from around the outdoor unit, can be done by a homeowner. However, diagnosing refrigerant charge issues, testing sensor resistance, or replacing components requires proper tools and in many regions a certified technician for refrigerant handling. It is recommended to have a qualified technician perform a full diagnosis before attempting a restart.

Resetting the unit may temporarily clear the fault code and allow the system to restart, but if the underlying cause is not resolved, the discharge temperature will exceed 110°C again and F4 will return. Repeated resets without addressing the root cause can accelerate compressor wear. A full diagnostic inspection should be completed before relying on a reset as a solution.