Goodman Heat Pump Error Code 05

Error code 05 on a Goodman heat pump indicates an open circuit condition in the compressor circuit. The control board cannot detect a complete electrical path to the compressor, which may be caused by a disconnected power supply, a failed compressor protector, or improper wiring between the compressor and the control board. The compressor will not run while this fault is active.

Error code 05 will prevent the compressor from operating, so the system is essentially protecting itself by not running. There is no immediate safety risk in the sense of fire or explosion from this fault alone, but you should not attempt to bypass or ignore the fault. Continuing to attempt system restarts without diagnosing the root cause could cause further damage to the compressor or wiring.

Resetting the unit by cycling the power may temporarily clear the fault code, but the error will return if the underlying cause has not been corrected. If the compressor protector tripped due to overheating, allowing the unit to cool before resetting may restore operation temporarily. However, a persistent open circuit caused by failed wiring, a damaged protector, or a failed compressor will continue to trigger code 05 until the defective component is repaired or replaced.

Some causes of error code 05 are within reach of a knowledgeable DIYer. Checking and resetting a tripped circuit breaker or replacing a blown fuse in the outdoor disconnect are straightforward tasks. Inspecting wiring connections at the compressor terminals is also possible with basic electrical knowledge and the power disconnected. However, testing the compressor protector and compressor windings with a multimeter, or replacing any of these components, is best handled by a certified HVAC technician.

Repair costs depend heavily on what is causing the open circuit. Replacing a blown fuse or resetting a breaker costs little to nothing beyond a service call fee, which typically ranges from $75 to $150. Replacing a compressor protector or repairing damaged wiring may run $150 to $400 including parts and labor. A failed compressor is the most expensive outcome, with replacement costs ranging from $800 to $2,500 or more depending on the unit size and refrigerant type.