35 Years of Field Experience · 700+ Five-Star Google Reviews · Licensed in SC & NC · Home of the 12-Year Labor Warranty
Heat Pump Problems We Diagnose and Fix
A heat pump that won't heat, blows cold air, gets stuck on aux heat or won't stop running almost always comes down to one clear cause, and finding it is the whole job. Guessing gets expensive. Coastline brings 35 years of field experience to heat pump repair across North Myrtle Beach, Little River and the Brunswick County beach towns, and every visit starts with a real diagnosis: what failed, why it failed, what it costs to fix, and whether your system is still worth the money. We repair all the major brands, including the electric heat pumps you'll find beside most homes on this coast.
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Signs Your Heat Pump Needs Repair
Heat pumps rarely die without warning. Most of them drop hints for weeks: a sound that wasn't there before, a room that's a little warmer than it used to be, a power bill that doesn't make sense. Call when you notice the hint, and the fix is usually smaller and cheaper than the one you'd need after it fails outright.
It's Not Heating or Cooling Properly
Lukewarm Air From the Vents
Put your hand over a vent. In cooling mode, the air should feel noticeably cold, usually 15 to 20 degrees cooler than the air going into the return. When it's only slightly cool, the most common causes are low refrigerant from a leak, a dirty outdoor coil that can't get rid of heat, or a weak compressor. In heating mode, lukewarm air can also mean the heat pump has quit and only the backup heat is working.
Stuck on Auxiliary or Emergency Heat
"AUX" on your thermostat means the electric heat strips in your air handler are helping out. A little of that on a cold morning is normal. Hours of it every day means the heat pump itself isn't carrying the load. The house may feel fine, which is exactly why this one sneaks up on people: the first sign is often a winter power bill that's double what it should be.
Noise, Ice and Short Cycling
Ice That Won't Clear
In cold, damp weather, a light frost on the outdoor coil is normal. The unit is built to melt it off by running a defrost cycle every so often, and you'll sometimes see steam rising when it does. What's not normal is a block of ice that keeps growing, or ice on the copper lines in summer. That points to a failed defrost board, a bad sensor, a fan that's stopped, or low refrigerant. Turn the system off and call; running it iced can ruin the compressor.
Turning On and Off Every Few Minutes
We call it short cycling. A heat pump that starts, runs a few minutes and shuts off again wears out its parts quickly and never gets the house comfortable or dry. The cause can be as simple as a clogged filter or a thermostat in a bad spot, or as serious as a system that was oversized from day one or an electrical fault.
Buzzing, Grinding or Hard Starts
A loud hum or buzz when the outdoor unit tries to start, with the fan not spinning, is very often a failing capacitor, the part that gives the motors their kick to get going. Grinding or squealing usually means a motor bearing is wearing out. Both are far cheaper to fix early than after the motor burns up.
What a Heat Pump Repair Visit Covers
You should know exactly what you're paying for before anybody opens a toolbox. Here's how a Coastline repair visit works.
Diagnosis First, Then a Clear Price
We test the system from the thermostat to the outdoor unit: power and wiring, refrigerant pressures, airflow across the indoor coil, the condition of both coils and the drain. Then we explain what we found, in plain English, and give you the price. Nothing gets replaced until you say so.
Electrical Parts
Capacitors, contactors (the switch that turns the outdoor unit on and off), relays, wiring and the control board. These are the parts most likely to fail after a hot summer, a lightning storm or a power surge, and they're often a same-visit fix.
Refrigerant and Leaks
A heat pump doesn't use up refrigerant the way a car uses gas. If it's low, there's a leak somewhere. Adding refrigerant without finding the leak only buys you a few weeks or months, so we look for the source and tell you what it takes to fix it properly.
The Repairs We Make Most
Reversing Valve and Defrost Controls
These two parts belong only to heat pumps. The reversing valve flips the system between heating and cooling; the defrost board and its sensors decide when to melt the ice off the outdoor coil. When either one acts up, you get heat pumps that cool in winter or freeze into a block of ice.
Fan and Blower Motors
The outdoor fan pulls air across the outdoor coil, and the indoor blower pushes air through your ducts. If either one weakens, the system works harder for less comfort, and you'll notice it first as weak airflow or a unit that seems to run forever.
Compressor Problems
The compressor is the heart of the heat pump, and the most expensive part to replace. Before anyone condemns it, the start components around it have to be checked, because a compressor that won't start is sometimes just a failed capacitor or relay. When the compressor itself is truly gone, we'll talk through whether repair or replacement makes more sense for your system's age.
Electric Heat Pump Repair
Nearly every heat pump around North Myrtle Beach is electric, paired with an indoor air handler and a bank of backup heat strips. That setup has one catch: when the heat pump starts to fail in winter, the heat strips quietly take over. The house stays warm, nobody notices, and the power bill climbs month after month. On every electric heat pump repair, we test the heat pump and the backup heat separately, so you know which one is actually heating your home and whether the strips and the sequencer (the switch that turns them on in steps) are working the way they should.
Repair or Replace Your Heat Pump?
Sometimes the honest answer is a new system. We'll tell you when it is, and just as important, when it isn't.
When Repair Makes Sense
The system is in good shape overall, the problem is a single part like a capacitor, contactor, fan motor or sensor, and it hasn't needed a string of repairs lately. Most of the calls we run end right here, with the system fixed and running the same day.
When Replacement Is Worth Considering
A Major Failure on an Older System
A dead compressor or a leaking outdoor coil on an aging system can cost a big share of what a new one costs. At that point, putting the money toward new equipment with a fresh warranty usually makes more sense.
Repeat Breakdowns
Three or four service calls in a couple of seasons is a pattern, and patterns rarely reverse themselves.
If replacement turns out to be the better path, our heat pump replacement and installation page explains how we size a new system and what the 12-Year Labor Warranty covers.
Heat Pump Repair Near the Water
Coastal heat pumps fail in a few ways inland units don't. Salt air works its way into the thin fins of the outdoor coil and into the electrical connections, and the corrosion it causes shows up as weak performance, failed contactors and leaks in the coil itself. Units on raised platforms on island homes also take more wind and spray. When we're on site for a repair, we'll point out any corrosion we see and talk through options like a thorough coil cleaning or protective corrosion coating. It's one of the reasons homeowners across the North Myrtle Beach area trust Coastline for heat pump service.
Heat Pump Repair Questions
Can I keep running my heat pump if it's iced over?
No. Turn the system off at the thermostat and call. Running a heat pump that's covered in ice can damage the compressor. Most thermostats let you switch to emergency heat, which uses only the heat strips, to keep the house warm until we get there.
Why does my heat pump run nonstop in summer?
On a 95-degree day with high humidity, long run times are normal; the system is doing exactly what it should. If it never shuts off on a mild day, it may be low on refrigerant, fighting a dirty coil or simply too small for the house.
Do you repair brands you didn't install?
Yes. We repair all the major heat pump brands, no matter who installed them.
Heat pump, AC and heating repair for North Myrtle Beach, Little River, Calabash and the north end of the Grand Strand. Licensed in South Carolina and North Carolina.
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