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.

Waiting rarely saves money and often turns a same-day repair into a longer, more involved job.
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.
Heat pumps run in both summer and winter, so we treat heat pump failures as urgent regardless of season.
Auxiliary heat strip diagnostics are included in the same visit when relevant.
Refrigerant charge is verified against heat pump-specific specs, which differ from standard AC charging.
From the first symptom to the final fix, these are the specific heat pump repair services our Brentwood-area crews are equipped for.
A stuck reversing valve is the single most common reason a heat pump gets stuck in one mode. This is one of the most requested heat pump repair calls we get across Brentwood, MO.
An outdoor unit that ices over and never defrosts usually points to a failed defrost thermostat or control board timing issue. Techs handling defrost cycle & control board repair carry the specific parts and tools this job calls for, not a generic kit.
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 Brentwood, MO.
We charge to the manufacturer's heat pump-specific target, not a generic number. 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. Techs handling outdoor unit icing diagnostics carry the specific parts and tools this job calls for, not a generic kit.
Indoor head unit and outdoor condenser are diagnosed as a connected system. This is one of the most requested heat pump repair calls we get across Brentwood, MO.

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.
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.
Outdoor unit was constantly covered in ice and I thought that meant it was broken.
Auxiliary heat strips weren't kicking in during a cold snap and the house couldn't keep up.
Ductless heat pump in the addition threw a code I couldn't find anywhere online.

This is one of the most common and most misdiagnosed heat pump failures.
Some frost during a normal defrost cycle is expected; ice that never clears points to a defrost board or thermostat fault.
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.
These systems have their own fault-code patterns that our techs are trained to read.
Call for a live arrival estimate based on current demand.

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