Symptom
Heat pump not heating?
A heat pump that runs but doesn't heat well may have a thermostat set incorrectly, a dirty filter, an iced-up outdoor coil, a low refrigerant charge, or a reversing valve or defrost problem. Heat pump air also feels cooler than furnace air even when working normally. If the house won't hold temperature, the system needs to be diagnosed.
Soon. In a hard freeze, no heat can become urgent. Call if the house is getting cold — emergency service runs 24/7.
What usually causes this.
These are the common possibilities, not a diagnosis. A page cannot tell which one it is — that takes a technician testing the system.
- Outdoor unit
- Thermostat
- Refrigerant lines
- The house itself
- Filter & return
- Thermostat setup
- Wrong mode, or a thermostat that isn't configured for a heat pump, can stop it heating properly or send it to backup heat at the wrong times.
- Restricted airflow
- A dirty filter or blocked returns reduce heating capacity just as they reduce cooling.
- Outdoor coil iced over
- Light frost is normal and melts during defrost. A solid block of ice means defrost isn't working.
- Low refrigerant charge
- A leak hurts heating as much as cooling, and sometimes more.
- Reversing valve
- The valve that switches the system between heating and cooling can stick, leaving the system blowing cool air.
- Very cold weather
- A heat pump's capacity falls as outdoor temperature drops. On the coldest nights, backup heat is designed to help.
What you can safely check.
- Set the thermostat to Heat (not Emergency Heat) and the fan to Auto.
- Replace a dirty filter and open all returns.
- Look at the outdoor unit. Light frost and steam during defrost are normal; a thick block of ice is not.
- Clear snow, leaves or debris from around the outdoor unit.
Leave these alone
- Chipping ice off the outdoor coil or pouring hot water on it.
- Anything involving refrigerant or the unit's electrical panel.
Call rather than book online if:
- The outdoor unit is encased in ice and not defrosting
- The house is losing heat in freezing weather
- The breaker trips again after one reset
What we check when we get there.
In order, and every time — the point of a diagnostic is to find out which cause it is before anything is replaced.
- 01The technician checks the thermostat configuration, airflow, refrigerant pressures, reversing valve and defrost controls.
- 02Auxiliary heat staging is checked too, so the system isn't quietly relying on expensive backup heat.
What it is likely to cost.
Thermostat and airflow fixes are inexpensive. Defrost boards, refrigerant leaks and reversing valves are larger repairs. You get the price before any work.
Repair or replace?
Heat pumps run year-round, so they tend to reach end of life sooner than a separate AC and furnace — commonly around 12–15 years. A major repair near that age is worth comparing against replacement.
Compare repair vs replacement- Diagnostic
- $89
- Defrost control board
- From $349
- Refrigerant leak / recharge
- From $499
- Reversing valve
- From $699
- Outdoor fan motor
- From $449
Prices are starting points for standard work in the Savannah area. Final price depends on the system and site, and is confirmed before work begins. Permits and code-required upgrades may be additional.
Questions people ask about this.
- Why does heat pump air feel cool?
- Heat pump supply air is usually warm rather than hot — noticeably cooler than a gas furnace's. It can still heat the house well; it just runs longer to do it.
- Should I switch to Emergency Heat?
- Only as a short-term measure if the heat pump has failed. Emergency heat usually runs on electric resistance, which is expensive, and it doesn't fix the underlying problem.
Work out the decision:Repair or Replace?
Further reading:Heat pump or gas furnace on the Georgia coast?
The service that fixes it.
Heat Pump Service & Installation is the work behind this symptom. Its page covers what is involved, how it is quoted and what we stand behind.
- 01Heat Pump Service & InstallationHeating and cooling from one system — well suited to our climate, and unforgiving of a bad install.
- 02Heating & Furnace RepairFurnace not lighting, blowing cold, or cutting out early? We get heat back and check it is safe.
- 03Maintenance PlansTwice-yearly service that catches small faults before they become July breakdowns.
Symptoms that sit next to it.
Systems rarely fail in one way only. If one of these is also true, say so when you book — it narrows the diagnosis before anyone arrives.
Furnace or heat pump not heating, blowing cold air, cycling or running up the bill.
- Furnace won't turn on or lightA gas furnace that won't light is most often a worn igniter, a dirty flame sensor, a clogged filter tripping a safety limit, or a thermostat or power problem.
- Furnace blowing cold airA furnace blowing cold air is often a thermostat set to fan On rather than Auto, a furnace that has shut its burners off on a safety limit, or an ignition problem.
- Furnace turning on and offA furnace that runs for a few minutes, shuts off and restarts over and over is short cycling.
- Heat pump iced up or stuck in defrostIn cold, damp weather a heat pump's outdoor coil collects frost, and the system runs a defrost cycle to melt it — steam and a few minutes of cooler indoor air are normal.
- Aux heat always on / high winter billAuxiliary heat is the backup — usually electric resistance — that helps a heat pump in very cold weather or during defrost.
Not sure which it is?Describe it to the assistant
Everything else we are called about.
The whole index, in three groups.
HUMIDITY, AIRFLOW & ENERGY BILLS
House feels humid or dampSome rooms too hot or coldPower bill suddenly higher
Get it looked at.
We cover Savannah, the Coastal Empire and the South Carolina Lowcountry. Tell us what the system is doing — you do not need to know the cause. The diagnostic price is given to you before the visit, and the repair price before any work starts.
No heat, or no cooling at all?Call rather than send a request — (912) 858-3737 is answered around the clock.