Despite its compact size, the thermal expansion valve is a key component of the air conditioning system: it precisely regulates the flow of refrigerant into the evaporator, where the fluid changes from liquid to gas, absorbing heat and cooling the air. It also separates the high and low pressure sides, helping to maintain overall system efficiency.

It plays a crucial role in ensuring proper compressor operation, as it directly affects workload and lubrication. For this reason, it is essential that it operates with maximum accuracy and, whenever the compressor is replaced, the valve should also be replaced.

Dirt, impurities, or debris in the circuit are among the most common causes of malfunction. Proper system maintenance is therefore essential to prevent failures, preserve performance, and ensure long-term reliability.