We service both air-source and ductless heat pump systems.
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.

Heat pump failure modes are different enough from standard AC that generic diagnostics often miss the actual cause.
No-heat calls in winter get the same priority as no-cool calls in summer.
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 Saint Charles, MO.
A stuck reversing valve is the single most common reason a heat pump gets stuck in one mode. Techs handling reversing valve diagnosis & repair carry the specific parts and tools this job calls for, not a generic kit.
We verify the defrost cycle actually triggers under test conditions. This is one of the most requested heat pump repair calls we get across Saint Charles, MO.
Backup electric heat strips that fail can leave a home without adequate heat during the coldest stretches. Techs handling auxiliary / emergency heat strip repair carry the specific parts and tools this job calls for, not a generic kit.
Heat pump refrigerant charging follows different specs than standard AC systems, especially across heating and cooling modes. Techs handling refrigerant charge & leak detection carry the specific parts and tools this job calls for, not a generic kit.
We distinguish between the two before recommending any repair. This is one of the most requested heat pump repair calls we get across Saint Charles, 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.
Reversing valve, defrost cycle, and refrigerant charge are tested against heat pump-specific specs before any quote.
Most reversing valve and defrost board repairs finish same-visit with parts carried on the truck.

System would only blow cold air no matter what mode I selected.
Turned out the defrost thermostat had failed, so it never actually triggered the defrost cycle.
Auxiliary heat strips weren't kicking in during a cold snap and the house couldn't keep up.
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.
Call for a live arrival estimate based on current demand.

Our heat pump repair crews are positioned throughout Saint Charles, MO to keep response times realistic, not just promised.
☎ Call +1-866-805-8548 for Saint Charles Service