What should I do if my heat pump is not heating?

What this symptom usually means

A heat pump that is not heating is different from a noisy unit, a frozen outdoor unit, or a water leak. In this case, the key clue is that the system runs but the home temperature does not rise as it should. That usually means the equipment is moving air without completing the heating cycle correctly, or it is producing some heat but not enough to overcome the home's heat loss.

What you can tell from the way it behaves

Normal airflow with little or no warmth often points toward a refrigerant, compressor, reversing valve, or control problem rather than a simple duct restriction. Weak airflow with poor heating shifts suspicion toward an indoor blower issue, a collapsed duct, or a zone damper problem. If only one room or one zone is cold while the rest of the house heats normally, the heat pump itself may be fine and the fault may be in the zone control, damper motor, or branch duct serving that area.

If you also see ice on the outdoor unit, hear the system run for long stretches, or notice the air gets colder during heating calls, the outdoor section may not be defrosting correctly or may not be moving refrigerant as it should. If there is a new buzzing, humming, or hard-start sound from outdoors and heat output dropped at the same time, technicians often find a failing capacitor, contactor, fan motor, or compressor-related issue. Water near the air handler during a heating complaint can happen during defrost or from a secondary drain issue, but it does not by itself explain why the system is not adding heat.

What a technician usually checks on a no-heat heat pump call

A service visit for this symptom typically starts with confirming that the thermostat and control board are sending a true heating call, then checking temperature rise, refrigerant pressures, compressor operation, outdoor fan operation, and whether the reversing valve is shifting into heat. On systems with auxiliary or emergency heat, the technician will also verify whether backup heat is energizing when it should and whether the heat pump is carrying the load before backup is needed. If one zone is cold, they may test damper operation and airflow room by room instead of treating it like a whole-system failure.

What affects repair cost

Cost depends heavily on whether the problem is a control issue, an airflow problem, or a sealed-system problem. Thermostat, relay, capacitor, or contactor repairs are often on the lower end, while blower motor, outdoor fan motor, defrost board, or reversing valve repairs are usually higher. Refrigerant leak diagnosis, leak repair, and recharge can become one of the more expensive outcomes because it involves sealed-system work and refrigerant. Typical 2025-2026 US repair ranges are roughly $150-$450 for common electrical parts, $400-$1,200 for many motor or board repairs, and about $800-$2,500+ when leak repair, reversing valve work, or major refrigerant-system repairs are needed.

If the unit is older, uses an expensive legacy refrigerant, or has both poor heating performance and compressor trouble, replacement may come up during the visit even though the service call started as a no-heat complaint. That is especially common when the system can still move air but cannot produce enough heat to hold temperature in cold weather.