Commander 4WD V8-4.7L VIN N (2006)
Expansion Valve: Description and Operation
Rear
VALVE-A/C EXPANSION
DESCRIPTION
The rear A/C expansion valve is of a thermostatic expansion valve (TXV) design and controls the amount of refrigerant entering the rear A/C evaporator.
The rear A/C expansion valve consists of an aluminum H-valve type body (1) with an integral thermal sensor (2) and is located on the bottom of the rear
HVAC housing, which extends through the rear floor panel behind the right rear wheel housing.
OPERATION
The rear A/C expansion valve controls the high-pressure, low temperature liquid refrigerant from the rear liquid line and converts it into a low-pressure,
low-temperature mixture of liquid and gas before it enters the rear A/C evaporator. A mechanical sensor in the rear A/C expansion valve monitors the
temperature and pressure of the refrigerant leaving the rear A/C evaporator through the rear suction line, and adjusts the orifice size at the rear liquid line
port to let the proper amount of refrigerant into the rear A/C evaporator to meet the vehicle A/C cooling requirements. Controlling the refrigerant flow
through the rear A/C evaporator ensures that none of the refrigerant leaving the rear A/C evaporator is still in a liquid state, which could damage the A/C
compressor.
The rear A/C expansion valve is factory calibrated and cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.
