Heat pump repair cost
Most heat pump repairs cost $180 to $900. A heat pump fails in every way an air conditioner does, plus two of its own: the reversing valve and the defrost control. Both often show up as a bill rather than a breakdown.
National average
$600
per project
On this page
- What the common repairs cost
- The two failures that are specific to a heat pump
- Frost is normal. Ice is not.
- Why the electricity bill is the real symptom
- Repair or replace
- Frequently asked questions
- My heat pump blows cool air in heating mode. Is it broken?
- What is emergency heat and when should I use it?
- Should I set the thermostat back at night?
- The outdoor unit steams after it runs. Is that a problem?
- Does a heat pump need servicing twice a year?
Most heat pump repairs cost $180 to $900. A heat pump is an air conditioner that runs backwards in winter, so it fails in all the ways an air conditioner does, plus two of its own: the reversing valve and the defrost control.
A diagnostic visit is $80 to $200, usually credited against the repair. Because a heat pump works year round, it accumulates roughly twice the running hours of a cooling-only system, and its parts wear accordingly.
What the common repairs cost
| Repair | Typical cost |
|---|---|
| Diagnostic visit | $80 to $200 |
| Run capacitor | $150 to $350 |
| Contactor | $150 to $400 |
| Defrost control board | $300 to $800 |
| Defrost sensor or thermostat | $180 to $450 |
| Outdoor fan motor | $350 to $800 |
| Blower motor, indoor | $400 to $1,100 |
| Reversing valve | $700 to $2,000 |
| Refrigerant leak search and repair | $400 to $1,600 |
| Refrigerant recharge, R-410A | $250 to $750 |
| Backup heat strips | $250 to $700 |
| Thermostat, heat pump compatible | $200 to $600 |
| Evaporator coil | $900 to $2,800 |
| Compressor | $1,800 to $4,000 |
Evening and weekend rates typically add 50% to 100%.
The two failures that are specific to a heat pump
The reversing valve is what makes the machine a heat pump rather than an air conditioner: it swaps which coil is releasing heat and which is absorbing it. When it sticks, the system runs fine in one mode and blows the wrong temperature in the other. The classic symptom is an air conditioner that cools perfectly all summer and blows cold air in December.
The valve body itself is a few hundred dollars, but replacing it means recovering the refrigerant, brazing the new valve in and recharging, which is most of a day. At $700 to $2,000 on a system past twelve years, it is worth pricing a replacement alongside it.
Defrost is the cycle that clears frost from the outdoor coil in cold weather. The system briefly switches to cooling mode, warming the outdoor coil, while the backup heat strips cover the house. When the defrost board or its sensor fails you get one of two pictures: an outdoor unit encased in ice, or a system that defrosts constantly and runs the expensive backup heat all winter. The second one shows up as a shocking electricity bill rather than as a fault.
Frost is normal. Ice is not.
A light coat of frost on the outdoor coil in cold, damp weather is the system working. It should clear itself every hour or two.
Solid ice covering the coil, ice on the fan, or a block of ice at the base of the unit is a fault. Turn the system to emergency heat, which locks out the compressor and runs the backup strips, and call someone. Running a heat pump with an iced coil damages the compressor.
Never chip ice off with anything. The coil is soft aluminium and the refrigerant lines run through it.
Why the electricity bill is the real symptom
Most heat pump faults do not stop the house being warm. They stop the heat pump doing the work and let the backup heat strips do it instead, and resistance heat costs two to three times as much per unit of warmth.
So a failed defrost sensor, a stuck reversing valve, a low refrigerant charge or a thermostat wired without a proper heat pump profile all present the same way: the house is fine and the bill has doubled.
If your winter electricity bill jumps and nothing about the house has changed, that is a service call, not a tariff problem.
Repair or replace
The same arithmetic as any system: divide the repair by the years it buys, compare to a replacement divided by fifteen.
An $8,000 heat pump over fifteen years is about $533 a year. A $350 capacitor that buys four more years is trivially worth it. A $2,000 reversing valve on a thirteen year old unit that might give three more is $667 a year, which is worse than replacing.
Replace rather than repair when:
- The compressor has failed out of warranty
- The reversing valve has failed and the system is past twelve years
- The system uses R-22 and has a leak
- You have had two significant repairs in two seasons
Heat pumps have improved genuinely in the last decade, particularly in cold weather output, so a replacement is more likely to be a real upgrade here than it is with a gas furnace.
Frequently asked questions
My heat pump blows cool air in heating mode. Is it broken?
Not necessarily. Heat pump supply air runs about 90 to 105°F, which is warm but below body temperature, so it feels cool on your hand. That is normal and it is the most common complaint from people used to a furnace. Cold air, as opposed to lukewarm, is a fault.
What is emergency heat and when should I use it?
It locks out the compressor and heats with resistance strips only. Use it when the heat pump has failed or the outdoor coil is iced, and switch back as soon as it is fixed. It is not a "get warmer faster" setting; it is an expensive fallback.
Should I set the thermostat back at night?
Less than you would with a furnace. A heat pump recovers slowly, and a deep setback brings the backup strips on to catch up, which costs more than the setback saved. Two or three degrees is fine; ten is counterproductive.
The outdoor unit steams after it runs. Is that a problem?
No, that is the end of a defrost cycle. Melted frost evaporating off a warm coil looks alarming and is exactly what should happen.
Does a heat pump need servicing twice a year?
Once a year is enough for most, but it should cover both modes, because a fault in the reversing valve or the defrost circuit only shows up in the season you are not in. Service in autumn if you only do it once.
Read next
Repair or replace your HVAC system$6,500 to $22,000per projectThe $5,000 rule says multiply the repair by the age of the system and replace above $5,000. It is memorable and it is wrong often enough to cost money. Here is the arithmetic that works, and the cases where it is not close.
Heat pump cost$5,000 to $13,000per projectA ducted heat pump costs $5,000 to $13,000 installed, typically near $8,000. The federal tax credit most guides still describe is, according to the IRS, no longer available.
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AC refrigerant recharge cost$250 to $2,000per projectA recharge costs $250 to $750 on R-410A and $600 to $2,000 on older R-22. But an air conditioner does not consume refrigerant. If yours is low, it is leaking, and refilling it is buying the same gas twice.
Thermostat installation cost$150 to $600per eachA thermostat costs $150 to $500 installed, or $250 to $600 for a smart one. Two things turn a simple swap into an expensive job: a missing common wire and a heat pump.