Expansion Valve: Description and Operation

THERMOSTATIC EXPANSION VALVE

Thermostatic Expansion Valve:

A thermostatic expansion valve (TXV) regulates the flow of refrigerant into the auxiliary A/C evaporator core. It is also the dividing point in the system between low- and high-pressure sides.

The temperature sensing bulb measures the temperature of the refrigerant in the suction line and transmits it to the TXV. This temperature variation regulates the refrigerant flow to the auxiliary A/C evaporator core.
- When the bulb senses a high temperature, the TXV opens and provides refrigerant through the auxiliary A/C evaporator core.
- When the bulb senses a low temperature, the TXV starts closing to shut off the refrigerant to the auxiliary A/C evaporator core.