Econoline E350 1 Ton V8-5.4L SOHC VIN L (1999)
Expansion Valve: Description and Operation
Thermostatic Expansion Valve
An A/C evaporator expansion valve 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 A/C evaporator expansion valve. This
temperature variation regulates the refrigerant flow to the auxiliary A/C evaporator core.
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When the bulb senses a high temperature, the A/C evaporator expansion valve opens and provides refrigerant through the auxiliary A/C evaporator
core.
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When the bulb senses a low temperature, the A/C evaporator expansion valve starts closing to shut off the refrigerant to the auxiliary A/C
evaporator core.
