Problem Center · Heat Pumps
Why Is My Heat Pump Not Heating?
Lukewarm or cold air in heating mode.
What could cause this?
- Defrost cycle (temporary and normal)
- Defrost control or sensor problems
- Low refrigerant
- Reversing valve problems
- Thermostat configured incorrectly for a heat pump
- Auxiliary heat not operating
What you can safely check
- Confirm the thermostat is in Heat
- Check the filter
- Clear snow and ice buildup around the outdoor unit — don’t chip ice off the coil
Don't open electrical panels or equipment cabinets, handle refrigerant, work on gas or combustion components, or bypass safety controls.
When it requires a professional
If the outdoor unit stays encased in ice or the house keeps losing temperature, request service.
How Air Mechanical diagnoses it
We check heating-mode operation, defrost, refrigerant circuit, auxiliary heat and thermostat configuration.
Every diagnosis starts with the system as it actually exists — equipment, controls, wiring and installation. The equipment has a brand. The problem has a solution.