What is the function of a thermal expansion valve (TXV)?

The function of a thermal expansion valve (TXV) is to regulate the flow of refrigerant based on the cooling load. This valve plays a critical role in the refrigeration cycle by controlling the amount of refrigerant that enters the evaporator coil.

When the cooling load increases—meaning more cooling is needed—the TXV allows more refrigerant to flow into the evaporator. Conversely, when the load decreases, it reduces the flow of refrigerant. This dynamic adjustment ensures that the system operates efficiently, maximizing cooling output while minimizing energy consumption. The TXV also helps maintain the correct superheat level, which is vital for the proper functioning of the compressor and overall system reliability.

Understanding this function is key for anyone involved in HVAC, as it illustrates the importance of managing refrigerant flow to maintain system performance and efficiency.