Heat Pump Repair

That symptom points directly at the reversing valve or its control circuit — the component that lets a heat pump run both directions. It can stick mechanically, lose its solenoid, or have a wiring fault. A technician diagnoses which failure mode and whether it's a repair or needs the valve replaced.

Normal heat pumps form some frost in heating mode and run a periodic defrost cycle to shed it. Heavy or persistent icing points at a defrost sensor, defrost control board, outdoor fan, or low-charge issue. Running the system covered in ice damages the compressor, so switch to auxiliary heat and get it diagnosed.

The individual components aren't dramatically different, but a heat pump has more of them — the reversing valve and defrost control have no counterpart on a straight AC. Diagnosis takes a technician familiar with heat pump logic; a shop that only repairs ACs will often misdiagnose the problem.

The same four factors as any HVAC repair-or-replace: age, nature of the failure, repair history, and how long you plan to stay. A failed capacitor on a seven-year-old system is a clear repair; a failed compressor on a fifteen-year-old system is almost always a replacement conversation.