Commander 4WD V6-3.7L VIN K (2007)
Expansion Valve: Description and Operation
Plumbing-Front
Description
DESCRIPTION
The A/C expansion valve controls the amount of refrigerant entering the A/C evaporator and is of a thermostatic expansion valve (TXV) design. The
A/C expansion valve consists of an aluminum H-valve type body (1) with an integral thermal sensor (2) and is located at the dash panel between the A/C
refrigerant lines and the A/C evaporator.
Operation
OPERATION
The A/C expansion valve controls the high-pressure, low temperature liquid refrigerant from the liquid line and converts it into a low-pressure,
low-temperature mixture of liquid and gas before it enters the A/C evaporator. A mechanical sensor in the A/C expansion valve monitors the temperature
and pressure of the refrigerant leaving the A/C evaporator through the suction line, and adjusts the orifice size at the liquid line port to let the proper
amount of refrigerant into the A/C evaporator to meet the vehicle A/C cooling requirements. Controlling the refrigerant flow through the A/C evaporator
ensures that none of the refrigerant leaving the A/C evaporator is still in a liquid state, which could damage the A/C compressor.
NOTE: Replacement of the refrigerant line O-ring seals and gaskets is required anytime a refrigerant line is opened. Failure to replace the rubber O-ring
seals and metal gaskets could result in a refrigerant system leak.
The A/C expansion valve is factory calibrated and cannot be adjusted or repaired and must be replaced if found inoperative or damaged.
