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Heat Pump Repair & Installation in Columbia, TN
Most heat pump repair in Columbia, TN comes down to a system that works harder than most: a heat pump is your AC in summer and your heater in winter, so it runs more months of the year than any other system in Maury County. We fix units that blow cool air in heat mode, ice over and stay iced, run all day without catching up, or drive the electric bill up on backup heat — and we install new systems sized for both seasons.
5-star ratedLicensed & insured in Tennessee25 years in businessColumbia, TN · Price in writing before work starts
AUX heat vs EM heat — the answer that saves people money
AUX heat: automatic, short-term
Your thermostat shows AUX when the heat pump asks its electric backup strips for help — during defrost, or when outdoor air is so cold the pump alone cannot hold the house. Short stretches are normal on cold mornings. AUX running most of the day is not.
EM heat: manual, emergency only
EM (emergency) heat is a setting you choose. It turns the outdoor unit off and heats with the strips alone. It costs much more to run. Use it only when the heat pump is broken, and only until it is fixed. If your thermostat has sat on EM heat since last winter, that is very likely why your bills are high.
Heat pump symptoms, in the words people use
| Symptom | What it often is |
|---|---|
| Blowing cool or lukewarm air in heat mode | Low refrigerant, reversing valve fault, or the system sitting in defrost or on weak backup heat |
| Outdoor unit covered in ice that never clears | Defrost control or sensor fault. A thin frost that melts away on its own is normal; a solid ice shell is not |
| Steam rising off the outdoor unit in winter | Usually normal — that is defrost. The fan stops, the unit steams, then it goes back to heating |
| Runs constantly and never reaches the setting | Undersized for the cold snap, low charge, dirty coils, or backup heat strips partly failed |
| Electric bill jumped in January | AUX or EM heat running far more than it should — often a heat pump fault hiding behind the backup heat |
| Stuck in one mode — heats in summer or cools in winter | Reversing valve or control problem |
Auxiliary strip heat uses about three times the electricity of heat-pump heating, and heating and cooling together can run to more than half of a single-family home’s energy use in extreme weather. That pair of facts explains most January bill shock in Maury County: the heat pump falters, the strips quietly carry the house, and the bill tells the story weeks later.
Source: Middle Tennessee Electric — cold-weather bill guidance. Checked November 2026.Defrost, or a fault? Tell them apart in two minutes
| What you see | Normal defrost | Call us |
|---|---|---|
| Frost on the outdoor unit | Thin, even frost that clears on its own | Thick ice shell that stays for hours or days |
| Steam off the unit | Yes — steam during defrost is the melt you are watching | Steam plus a house that keeps getting colder |
| Outdoor fan stops | Briefly, while defrost runs | Fan never restarts, or hums without turning |
| Cool air at the vents | A few minutes while AUX heat catches up | Cool or lukewarm air for an hour or more |
| AUX on the thermostat | Short stretches on cold mornings and during defrost | AUX most of the day at 45°F outside — the pump is not doing its share |
| Ice after a storm | Light ice that the next defrost clears | Unit iced solid after freezing rain and not clearing — EM heat until we get there is the right call |
Do heat pumps work in a Tennessee winter?
Yes, and Columbia is good heat pump country: winters are cold in snaps, not cold for months. A heat pump moves heat instead of making it, so it heats at a lower cost than electric strips through most of the season. As outdoor air drops toward freezing, each run moves less heat, so backup AUX heat helps in short stretches. Gas heat still suits some homes — long rural gas runs, houses with weak insulation, owners who want the hottest supply air. We will lay out both for your house on a replacement quote instead of pushing one answer for every address. That comparison is on the replacement page.
Below 40 degrees, and the house that stays damp
Two heat pump complaints come up every season, and both have plain answers. Below about 40 degrees outside, a heat pump moves less heat per run, so runs get longer and AUX heat helps more often — that shift is expected. What is not expected: AUX carrying the house all day in mild weather, cool air in heat mode for an hour or more, or a unit iced solid and not clearing. Those are faults, covered in the tables above, not cold-weather behaviour to live with.
Running but not drying the house: a heat pump in heat mode does not remove humidity the way it does in cooling mode, and in cooling season a system that short-cycles, is oversized, or has airflow trouble can hold the temperature while the house still feels damp. If rooms feel clammy, or you are seeing moisture or musty smells that will not clear, measure the humidity first — the target range and the fix order are on the air quality & dehumidifiers page. Drying is its own job; a bigger heat pump is not the fix for it.
Thermostat settings that keep a heat pump bill sane
| Setting habit | Do this | Skip this |
|---|---|---|
| Mode | Leave it on Heat all winter. Let the system bring AUX heat in and out on its own | Sitting on EM heat "just in case" — that is strips-only heating at strips-only prices |
| Night setback | Small moves, a couple of degrees, or none at all | Big drops at night and big climbs at 6 a.m. — the morning climb calls AUX heat to help, and the saving is gone |
| Fan | Auto, so the fan rests when the system rests | Fan On all winter — it can blow cool-feeling air between heating runs and run up the meter for nothing |
| After a fix | Switch back from EM to Heat the same day the pump is repaired, and watch the first cold night | Forgetting the switch for a month. We check it on every winter visit because it happens that often |
Heat pump noises, sorted
Normal, mostly
A whoosh and a pause when defrost starts. A louder hum on the coldest mornings, when the compressor works hardest. Clicking from the thermostat as a cycle starts.
Call about it
A new rattle or buzz that was not there last winter. Ice building with a grinding fan. The system starting and stopping every few minutes on a mild day.
Turn it off and call
Screeching, metal-on-metal grinding, or a burning smell from the air handler. Switch to EM heat if you need heat to stay safe, and tell us you did — that detail helps the diagnosis.
Heat pump, gas furnace, or dual fuel? The Columbia comparison nobody else publishes
How the heat gets made is the whole difference. A heat pump moves heat — the reversing valve flips the refrigerant flow, so the same unit that pulls heat out of the house in July pulls heat out of the outdoor air in January. A furnace makes heat by burning fuel. Dual fuel pairs the two and lets the thermostat pick. Lee and Hiller both sell all three in Columbia; neither publishes the side-by-side. Here it is, for a Maury County winter:
| Heat pump + electric strips | Gas furnace + AC | Dual fuel (heat pump + gas furnace) | |
|---|---|---|---|
| Heats by | Moving heat; strips back it up | Burning gas; a separate AC cools | Moving heat most days; gas takes over in deep cold |
| Cold-snap behaviour | Output per run drops as air gets colder; AUX strips cover the gap in short stretches | Full heat at any temperature Columbia gets; hottest supply air of the three | Switches to gas before strips would run long, so the bill spike is smaller |
| Bill risk | A fault can hide behind the strips — AUX uses about three times the electricity, per Middle Tennessee Electric | Gas use rises in cold weather, but there is no silent electric backup to miss | Lowest of the three in a hard winter, if the changeover is set up right |
| Fits best | All-electric homes — most Spring Hill subdivisions and much of the county | Homes with gas already at the house, in town and on gas runs out of it | Homes with gas that want heat-pump running costs without strip-heat winters |
| Watch out for | One unit wears from both seasons; thermostat setup decides the winter bill | Two appliances to service; the furnace needs yearly safety checks | Most equipment and controls of the three — the setup and the changeover setting are the job |
When a heat pump goes in: what install day covers
Sized for both seasons, not just cooling tons
The load calculation runs for a January night as well as a July afternoon. A unit sized only for summer is the one that lives on AUX heat all winter.
Old unit out, refrigerant recovered
The old charge is recovered, not vented — federal rule, and part of the job on every changeout we do.
Line set checked, pad level, unit set
Lines flushed and tested or replaced, the outdoor unit set level with clear airflow, and the air handler matched to it — a mismatched pair never reaches its rating.
Every heat strip tested, one by one
Strips get tested at install, not discovered dead on the coldest night of the year. The count and the test go on the paperwork.
Defrost and thermostat set up in front of you
We run a defrost cycle, set how AUX heat is allowed to help, and show you the Heat / AUX / EM settings on your own thermostat before we leave.
The two ratings on a heat pump quote — SEER2 and HSPF2
A heat pump carries two season ratings because it works two seasons. SEER2 rates cooling: how much cooling you get for the electricity used across a summer. HSPF2 rates heating the same way across a winter. A Columbia heat pump heats far more hours than most owners expect — every night from the first cold snap in November through the last one in March — so the HSPF2 number is not fine print here. What the ratings do not measure: sizing, duct leaks, refrigerant charge, and where the AUX heat lockout is set. A high-rated unit with the strips carrying half the winter will bill like a cheap one. When we quote a heat pump, both ratings are on the paper next to the Manual J load calculation and equipment pick that chose the size, and the lockout setting is part of the thermostat setup before we leave.
Proof on heat pump work, not promises
- Licensed & insured in Tennessee, Columbia shop at 1230 Industrial Park Rd — one number for sales, service, and the 2 a.m. call
- Strip and defrost tests in writing: which heat strips were tested, what the charge measured, and how defrost behaved on the visit — the three readings that decide a heat pump winter
- Your thermostat settings recorded on the invoice, including how AUX heat is set to help, so a changed setting is easy to spot later
- Both prices in writing when a repair and a replacement are both fair — with the fuel comparison above priced for your house, not a brochure
Related: the two things that decide a heat pump bill
Heat pump repairs cluster around two neighbours. The first is the control: a thermostat set up without AUX lockout, or left sitting on EM heat, can undo a healthy system — that setup work lives on the thermostats & zoning page. The second is upkeep: coils, charge, and defrost checks twice a year keep a heat pump off its strips, which is the core of our maintenance visits. When the outdoor unit stops outright on a freezing night, skip both pages and use the emergency one.
Heat pump running all day, or sitting on AUX heat?
That pattern costs real money in Maury County — AUX strips use about three times the electricity. Call and describe what the thermostat shows. We test the pump, the strips, and the defrost cycle, then price the fix in writing.
Licensed & insured in Tennessee · ★★★★★ 5-star rated · 25 years in business · 1230 Industrial Park Rd, Columbia, TN
Heat pump FAQs
My heat pump blows cool air for a few minutes. Is that normal?
It can be. During defrost, the system briefly reverses to melt frost off the outdoor coil, and the air from the vents cools until AUX heat catches up. Cool air for an hour, or a house that keeps losing temperature, is not defrost — that is a service call.
How long should a heat pump last here?
About 10 to 15 years is the common range in the Southeast. Heat pumps here run both seasons, and summer humidity is hard on coils and electronics, so Maury County systems tend to live at the shorter end if they are not maintained.
Should I cover my heat pump in winter?
No. A heat pump needs open airflow all winter because it heats with that same outdoor unit. Keep leaves and shrubs a couple of feet away, and keep the top clear of anything that can fall or drip onto it, but do not wrap it.
Heat pump or furnace for my next system?
If you have gas at the house and like hot supply air in cold snaps, a furnace with AC — or a dual-fuel setup that pairs a heat pump with a gas furnace — is worth pricing. If you are all-electric, a heat pump is nearly always the right tool here. We price the options that fit your house and fuel, in writing.
Should I switch to EM heat when it gets really cold?
No — cold weather alone is not a reason. Leave the thermostat on Heat and let AUX heat come and go on its own; short AUX runs in a cold snap are the system working as built. EM heat turns the outdoor unit off and heats with the strips alone, at a much higher cost per hour. Use it only when the heat pump itself cannot run — broken, iced solid and not clearing, or damaged — and switch back to Heat the day it is fixed.
AUX heat has been on all day and it is only 45 degrees out. Is that right?
No. At 45 degrees a healthy heat pump should carry the house with little or no AUX help. AUX on for hours in mild weather usually means the heat pump is not doing its share — low charge, a weak outdoor fan or capacitor, a defrost fault, or a thermostat set up wrong, including one left sitting on EM heat. That is a service call, not a setting to live with, because the strips are quietly running your bill up.
Heat pump bill up, house not keeping up?
Call before another month runs on strip heat. We find why the pump is not carrying the house and put the repair price — and the replacement price, when age makes it fair — in writing.
Licensed & insured in Tennessee · ★★★★★ 5-star rated · 25 years in business · 1230 Industrial Park Rd, Columbia, TN