Heat pumps fail differently than standard AC or furnace systems, and diagnosing them requires understanding the reversing valve and defrost board specifically.
Auxiliary heat strip issues are checked alongside the heat pump itself.
If you're dealing with a system stuck blowing cold air in heating mode, an outdoor unit that's iced over and won't run its defrost cycle, or a system that switches modes but never actually reaches set temperature, you already know a heat pump that seems to be 'not heating' is often actually a reversing valve or defrost cycle problem, which a technician trained mainly on standard AC systems can easily misdiagnose.

Most heat pump repair problems give some warning before they turn into a system stuck blowing cold air in heating mode, an outdoor unit that's iced over and won't run its defrost cycle, or a system that switches modes but never actually reaches set temperature — catching it early usually means a shorter, cheaper fix.
AAA Pro HVAC built its heat pump repair process around one idea: diagnose first, quote honestly, fix it right.
We're licensed, insured, and staffed with techs who've spent years specifically on heat pump repair, not general handyman work with an HVAC certificate bolted on.

Our techs are specifically trained on reversing valves, defrost boards, and auxiliary heat systems, not just general AC repair logic.
Heat pumps run in both summer and winter, so we treat heat pump failures as urgent regardless of season.
You get a quoted price after the reversing valve and defrost cycle are actually tested, not billed for trial-and-error.
Refrigerant charge is verified against heat pump-specific specs, which differ from standard AC charging.
Every job starts with a real diagnosis, not a guess — here's the full scope of what our heat pump repair technicians handle across Ellington, MO.
We test the valve's solenoid directly rather than assuming based on symptoms alone. This is one of the most requested heat pump repair calls we get across Ellington, MO.
We verify the defrost cycle actually triggers under test conditions. This is one of the most requested heat pump repair calls we get across Ellington, MO.
We test heat strip elements and the relay controlling them separately. This is one of the most requested heat pump repair calls we get across Ellington, MO.
We charge to the manufacturer's heat pump-specific target, not a generic number. This is one of the most requested heat pump repair calls we get across Ellington, MO.
Some icing is normal during defrost cycling; persistent icing that never clears points to a genuine fault. This is one of the most requested heat pump repair calls we get across Ellington, MO.
Indoor head unit and outdoor condenser are diagnosed as a connected system. Techs handling ductless heat pump system repair carry the specific parts and tools this job calls for, not a generic kit.

That detail determines which specialized tools ride along.
Heat pump-trained technicians arrive with reversing valve and defrost diagnostic equipment already loaded.
Flat-rate pricing follows the confirmed diagnosis.
Workmanship is guaranteed and documented on your invoice.

System would only blow cold air no matter what mode I selected.
Outdoor unit was constantly covered in ice and I thought that meant it was broken.
They tested the relay separately from the strips themselves and found the actual fault fast.
Tech recognized it immediately as a defrost-related fault specific to that brand.

Often a stuck reversing valve, which controls whether the system is in heating or cooling mode.
If the unit stays iced for more than an hour, that's worth a service call.
Heat pumps have a reversing valve, defrost cycle, and often auxiliary heat strips that standard AC systems don't have.
If auxiliary heat isn't kicking in properly, that's a specific fault we can test for.
Yes — indoor head units and outdoor condensers on ductless heat pump systems are within our service scope.
No-heat heat pump calls get year-round priority dispatch across Ellington, MO.

Whether you're in the heart of Ellington or one of the surrounding communities, dispatch routes the closest available technician.
☎ Call +1-866-805-8548 for Ellington Service