Thermostatic Expansion Valves (TXV)

The thermostatic expansion valve (TXV) is also known in the field simply as the expansion valve. It regulates the flow of refrigerant into the evaporator so as to keep the superheat at the evaporator outlet constant: the sensing bulb reads the temperature of the evaporator outlet pipe, and the valve opens and closes accordingly.

This category contains Danfoss TE, TN, TS and TEZ, Sanhua RFKA, RFKH and RFG, Honeywell and Sporlan thermostatic expansion valves, as well as the top and bottom bodies of the Danfoss modular system. Orifices are in a separate category.

How to Choose the Right Valve

• Refrigerant: The valve is set for a specific refrigerant (R134a, R404A, R407C, R410A, R22…); it is not used for another refrigerant.
• Internally / externally equalised: If the pressure drop across the evaporator is high or a distributor is used, an externally equalised valve is chosen.
• Connection: Flare or solder (ODF solder connection).
• Capacity and MOP: The valve/orifice size is selected according to the system capacity; in low-temperature applications a valve with MOP is preferred.