What is the purpose of a thermal expansion valve in an HVAC system?

The purpose of a thermal expansion valve in an HVAC system is primarily to regulate refrigerant flow to the evaporator. This component controls the amount of refrigerant entering the evaporator, ensuring that it matches the evaporator's cooling capacity and operational conditions. By doing so, it helps maintain optimal pressure and temperature levels, preventing both underfeeding and overfeeding of the refrigerant.

When the refrigerant flows into the evaporator at the right rate, it allows for efficient heat absorption from the indoor air, facilitating proper cooling of the space. This regulation ensures that the system operates effectively, improving energy efficiency and system performance while also extending the life of the equipment. The thermal expansion valve plays a critical role in the refrigeration cycle, helping to achieve the desired cooling output by managing the transition of refrigerant between phases effectively.