Cary Heat PumpCary, North Carolina (984) 348-9940
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TroubleshootingUpdated February 20265 min read

Heat pump not heating? 7 things to check before you call

A meaningful share of the "broken" heat pumps we get called about in Cary are fixed in five minutes, for free, by the homeowner, once they know where to look. Work down this list in order.

Safety first: these checks involve nothing more invasive than a thermostat, a filter and a breaker panel. If anything smells burnt, sparks, trips repeatedly or involves refrigerant lines, stop and call us at (984) 348-9940.

1. Make sure it's actually broken

Heat pump air feels different. A furnace blasts 120°F+; a heat pump delivers a steady 90–100°F, warmer than your skin but cool-ish to the hand. If the air feels lukewarm but the house is holding temperature, nothing is wrong. Only proceed if the indoor temperature is genuinely dropping.

2. Thermostat: the embarrassing classics

  • Mode is HEAT, not COOL or OFF (someone always bumped it)
  • Set point at least 2°F above current room temperature
  • Fresh batteries if your model uses them, a dying thermostat fails weirdly
  • A "hold" or vacation schedule isn't overriding you

3. The air filter

A choked filter starves airflow until the system protects itself by shutting down or icing up. If the filter looks like a lint trap, swap it, then give the system 30–60 minutes to recover before judging the result.

4. Breakers, both of them

Heat pumps typically have two breakers: one for the outdoor unit, one for the indoor air handler. A tripped outdoor breaker produces a very convincing "broken" system where the fan blows unheated air. Flip any tripped breaker fully OFF, then ON. If it trips again, stop, that's an electrical fault, and it's our job.

5. Is the outdoor unit doing anything?

With the thermostat calling for heat, the outdoor fan should spin and the unit should hum. Dead silence outside while the indoor fan runs points to a contactor, capacitor or power issue, quick fixes for a tech, not DIY territory.

6. Frost vs. ice block

A light frost coating in winter is normal, the unit periodically defrosts itself (you may see steam; also normal). But if the unit is encased in ice like a freezer-burned popsicle, the defrost system has failed. Switch to Emergency Heat at the thermostat to keep the house warm and book a repair, running it iced damages the compressor.

7. Vents and returns

Walk the house: supply vents open and unblocked by rugs and furniture, return grilles clear. Closed vents in a few rooms ("to save energy", it doesn't) throw off airflow balance enough to cause real problems.

If you got here and it's still cold: you've already done the diagnostic groundwork, your repair visit will be faster and cheaper for it.

When you call, tell us what you found

"Outdoor unit silent, breakers fine, filter new", that one sentence puts the right parts on the truck before we leave the shop. Most repairs that start with a good description finish in a single visit.

Call (984) 348-9940, same-day slots

Prevent the next one: the maintenance checklist covers the habits that stop most of these problems before they start.

Call (984) 348-9940