Heat pump repair
Most heat pump problems trace back to a handful of causes. Here is how to spot them, what repairs cost, and when to fix versus replace.
Most common heat pump problems
| Symptom | Likely cause |
|---|---|
| Not heating or cooling | Thermostat, dirty filter, low refrigerant, or below the balance point |
| Won't turn on | Tripped breaker, capacitor or contactor failure |
| Frozen / iced outdoor unit | Defrost-control fault, low refrigerant, or airflow restriction |
| Short-cycling | Oversized unit, dirty coil, thermostat, or refrigerant issue |
| Strange noises | Loose parts, failing motor bearings, or compressor problems |
| Stuck on aux/emergency heat | Compressor or reversing-valve fault |
See our targeted guides for a heat pump not heating and heat pump noises.
Typical repair costs
Most repairs run $150–$650; major parts cost more. Full breakdown on our repair cost page — in brief: capacitor $150–$400, contactor $150–$350, refrigerant leak $200–$1,500, reversing valve $600–$1,300, compressor $1,500–$4,500.
DIY vs professional repair
Safe to DIY: replacing filters, clearing debris and snow from the outdoor unit, resetting a tripped breaker, and checking the thermostat. Call a licensed technician for: anything involving refrigerant, electrical components (capacitor/contactor), the compressor, or the reversing valve — these require tools, EPA certification and carry safety risks.
Repair or replace?
A common rule: if a repair costs more than half the price of a new system and your unit is over 10 years old, replacement is usually the better value — especially since a new heat pump is far more efficient and may qualify for state/utility rebates. A young unit with a cheap fix is worth repairing. Compare with our cost calculator.
Frequently asked questions
How much does heat pump repair cost?
Most repairs run $150–$650; a compressor or major refrigerant repair can reach $1,500–$4,500. A diagnostic service call is usually $75–$200.
Why is my heat pump not working?
Common causes are a tripped breaker, a dirty filter, a failed capacitor or contactor, low refrigerant, or simply running below its balance point in extreme cold.
Can I repair a heat pump myself?
You can handle filters, debris, breakers and thermostat checks. Leave refrigerant, electrical and compressor work to a licensed, EPA-certified technician.
Is it worth repairing an old heat pump?
If the repair exceeds half the cost of a new unit and the system is 10+ years old, replacing is usually the better value.
How do I fix a heat pump myself?
Start with the safe basics — check the thermostat is on Heat, replace a dirty filter, reset a tripped breaker, and clear snow/debris from the outdoor unit. Refrigerant, electrical (capacitor/contactor), compressor and reversing-valve problems need a licensed technician.
Related
Sources & further reading
Educational guide, reviewed against US DOE & ENERGY STAR guidance and updated June 2026. Estimates only — not a substitute for a professional assessment or Manual J load calculation.