What is the purpose of a thermal expansion valve (TXV) in HVAC systems?

The thermal expansion valve (TXV) plays a critical role in HVAC systems by regulating the flow of refrigerant. Its primary function is to control the amount of refrigerant that enters the evaporator coil based on the cooling demands of the system and the temperature of the refrigerant leaving the evaporator. By modulating the flow, the TXV ensures that the correct amount of refrigerant is available to absorb heat effectively, optimizing the cooling process and improving overall system efficiency.

This regulation is essential because if too much refrigerant enters the evaporator, it can lead to inefficient operation and potential flooding of the evaporator, while too little refrigerant can result in inadequate cooling. Therefore, the TXV helps maintain an optimal balance, contributing to the system's performance and reliability.