HVAC Guide
Heat Pump Not Heating? Normal, or a Fault
By All Purpose Anytime Services LLC
Check two things first. Is the air warmer than the room, even if it feels cool on your hand? That is normal. Is backup heat running for hours when it is mild outside? That is not, and it shows up on the power bill before it shows up as a breakdown.
What is normal
A heat pump sends out air that is warm, but not as hot as a furnace. It runs longer cycles to get the house there. Steam off the outdoor unit in winter is a defrost cycle clearing ice. That is normal too.
What is not
- The outdoor unit stays iced over and never clears
- Backup heat runs for hours when it is mild outside
- It cools fine in summer but will not heat
- It runs all the time and never shuts off
- A loud bang or grinding from the outdoor unit
The usual causes
A failed defrost control or sensor leaves the coil iced. A reversing valve that sticks leaves the system cooling when you asked for heat. Low refrigerant cuts output. A thermostat set up wrong lets the expensive backup heat come on too early.
That last one is common and cheap to fix. It is also the one that doubles a winter bill.
What to check before you call
- The thermostat is on heat, not auxiliary heat only
- The filter is clean
- Snow and leaves are clear of the outdoor unit
- The breakers for both the outdoor unit and the air handler are on
Heat Pump Acting Up?
Tell us what it is doing. We check the defrost, the backup heat and the thermostat setup.