What's normal in a Kentucky winter
Steam from the outdoor unit, air that feels cooler than a furnace's, and an "Aux" light on the thermostat are all normal for a heat pump. Here's why.
Defrost cycles and steam
In cold, damp weather, frost builds up on the outdoor coil. Every so often the heat pump switches into defrost for a few minutes to melt it. The outdoor fan stops, you may hear a whoosh, and steam rises off the unit. That's melting frost, not smoke.
Cooler air from the vents
When it's in the 30s outside, a heat pump's supply air often runs somewhere in the 90s. That's warm enough to heat the house, but it's cooler than your skin, so it can feel lukewarm on your hand. A gas furnace blows much hotter air, which is why the difference is so noticeable.
Aux heat and emergency heat
Aux heat is your backup, usually electric heat strips. It comes on by itself during defrost, on the coldest days, and when you bump the thermostat up several degrees at once. Emergency heat is a setting you choose by hand. It shuts the heat pump off and runs only the backup, so save it for when the heat pump is broken.
Signs of a real problem
These signs mean something is wrong, not just cold weather.
- Ice that never clears. Light frost is normal. A coil encased in solid ice, or ice that stays after a defrost cycle, points to a defrost control problem, low refrigerant or an outdoor fan issue. Don't chip at it.
- Aux heat running all the time. If "Aux" is on most of the day in mild weather, or your electric bill jumps, the heat pump isn't carrying its share.
- Stuck in defrost. An outdoor fan that stays off and cool air that lasts well past a few minutes usually means a defrost board or sensor problem.
- Reversing valve trouble. Cool air in heat mode, or warm air in cool mode, can mean the reversing valve, its solenoid or the thermostat wiring has failed.
- Cold air in heat mode, outside of defrost. That can be low refrigerant, a compressor that isn't running or a thermostat set up wrong.
- Outdoor fan not running. A bad capacitor or fan motor lets the coil ice up fast. Switch to emergency heat and call us.
What the $39 diagnostic special covers
The diagnostic ($39 with our online special, regularly $79) checks the heat pump's refrigerant circuit, controls and backup heat, usually in 30 to 45 minutes:
- Refrigerant pressures and temperatures in the current mode
- Reversing valve and solenoid operation
- Defrost control board, sensor and timing
- Outdoor fan motor, capacitor and contactor
- Compressor amp draw
- Aux heat strips, sequencers and relays
- Thermostat setup, including the reversing valve and aux heat settings
- Filter, blower and outdoor coil
You get a firm, flat-rate repair price before any work starts. If you approve it, the $39 is credited in full. If you don't, the $39 is all you owe. To get the $39 price, just mention our online special when you call or text; otherwise the diagnostic is our regular $79.
Heat pump or furnace in Kentucky?
For most Central Kentucky homes, a heat pump handles the bulk of the winter well, and it cools the house all summer too. Our winters spend a lot of time in the 30s and 40s, where heat pumps work efficiently. On the coldest nights, the backup heat does more of the work.
If your home has natural gas, a dual fuel setup is worth a look. It pairs a heat pump with a gas furnace. The heat pump runs through the mild and moderate days, and the furnace takes over below an outdoor temperature we set with you.
If your home is all-electric, a heat pump with electric backup heat is the usual choice. We'll talk through your home and give you options for heat pump installation, never a one-size answer.
Heat Pump Service questions
Why is steam coming off my heat pump in winter?
That's almost always a normal defrost cycle. Frost builds up on the outdoor coil in cold, damp weather, and the heat pump reverses for a few minutes to melt it. The fan stops and steam rises as the frost melts. If the unit is steaming constantly, or you see smoke or smell burning, turn it off and call.
Why does my heat pump blow cool air?
Heat pump air is warm, but not as hot as a furnace's. In the 30s outside, it's often in the 90s, which can feel cool on your hand. During defrost it can feel cooler for a few minutes. If it blows cold for long stretches, or the house won't hold temperature, something needs checking.
What does "Aux heat" mean on my thermostat?
Aux means your backup heat is running, usually electric heat strips or a furnace. It's normal during defrost, on very cold days and after you raise the temperature several degrees at once. If Aux stays on most of the day in mild weather, the heat pump itself may not be working properly.
When should I use emergency heat?
Only when the heat pump itself is broken, like an outdoor unit that's iced solid, making a bad noise or not running. Emergency heat shuts the heat pump off and runs only the backup heat, which usually costs more to run. Switch to it, then call us, and switch back once the heat pump is repaired.
Is it normal for my heat pump to run nonstop in cold weather?
Long, steady run times are normal when it's cold. Heat pumps are designed to run longer and gentler than furnaces. What isn't normal is a house that keeps losing ground, a coil that stays iced, or aux heat running most of the time. Any of those is worth a diagnostic.
Do heat pumps work in Kentucky winters?
Yes. Central Kentucky winters spend much of their time in the 30s and 40s, where heat pumps do well. Output drops on the coldest nights, which is what backup heat is for. If you have natural gas, a dual fuel system that pairs a heat pump with a gas furnace is another option we can quote.
How much does heat pump repair cost?
It depends on what failed, so we don't quote repairs sight unseen. With our online special the diagnostic is $39 (regularly $79; just mention it when you call or text). After it, you get a firm, flat-rate repair price before any work starts, and the $39 is credited in full if you approve. There are no overtime fees on nights, weekends or holidays.
Do you work on ductless mini-splits?
Yes. Ductless mini-splits are heat pumps too, and we service and repair them along with ducted systems. The same $39 diagnostic special and flat-rate pricing apply. Common problems include dirty filters and coils in the indoor heads, drain issues and outdoor units icing up in winter.
Where we work
Lexington and nine nearby towns, with no travel surcharge and the same flat-rate pricing everywhere.