Expansion Valve (TXV) Replacement — AC Repair

Professional Expansion Valve (TXV) Replacement — AC Repair in Asheville & Western NC

The Precision Valve Behind Efficient Cooling

The thermostatic expansion valve (TXV) regulates exactly how much liquid refrigerant enters the evaporator coil. Getting this metering right is essential — too much refrigerant floods the coil and threatens the compressor, while too little starves the coil and slashes cooling output. When a TXV fails, it usually freezes in one position, either flooding or starving the evaporator and producing symptoms like poor cooling, ice buildup, elevated head pressure, or compressor overheating.

A Tricky Diagnosis We Handle Correctly

TXV failures are notoriously difficult to confirm because the symptoms mirror other refrigerant-side issues. Low superheat might point to a stuck-open TXV or simply an overcharge. High superheat could mean a stuck-closed TXV or a low charge from a refrigerant leak. Our technicians rely on superheat and subcooling measurements, temperature differentials, and pressure analysis to conclusively isolate the TXV before recommending replacement.

Detailed, High-Precision Replacement

Swapping a TXV requires recovering the existing refrigerant, removing the faulty valve, brazing in a correctly matched replacement (sized for your system's tonnage and refrigerant type), installing a new filter-drier, evacuating the system under vacuum, and charging to manufacturer specs. It is intricate work demanding proper tooling and training — exactly the type of AC repair Quality Mechanical performs with expertise for homeowners across Asheville and Western NC.