Expansion Valve: Service and Repair

THERMAL EXPANSION VALVE (TXV)

REMOVAL

IMPORTANT: Verifying the purity of the refrigerant with a refrigerant purity identifier before recovery is recommended.




1. Recover refrigerant using an approved refrigerant recovery system.

CAUTION: DO NOT REMOVE HOSES OR LINES BEFORE SYSTEM IS FULLY DISCHARGED.

2. Remove air cleaner cover and air induction hose at intake manifold.




3. Remove suction hose from TXV.
4. Remove liquid line from TXV.




5. Remove TXV from evaporator.

INSTALLATION




1. Lubricate with R-12 Refrigerant oil (mineral) and install new O-rings on evaporator pipes. Remove protective covers from TXV.
2. Install TXV on evaporator and torque bolts.

Torque:
Thermal Expansion Valve (TXV)-to-Evaporator: 10 N.m (89 in-lbs)

NOTE: Use only R-12 Refrigerant oil (mineral) to lubricate O-rings. Use of R-134a (PAG) oil will cause premature corrosion of fitting joints.




3. Lubricate with R-12 Refrigerant oil (mineral) and install new O-rings on suction hose and liquid line.
4. Install liquid line to TXV. Install and torque bolt.

Torque:
Liquid Line-to-Thermal Expansion Valve: 25 N.m (19 ft-lbs)

5. Install suction hose to TXV. Install and torque bolt.

Torque:
Suction Hose-to-Thermal Expansion Valve: 25 N.m (19 ft-lbs)




6. Install air cleaner cover and air induction hose.
7. Evacuate, charge, and leak test A/C system.
8. Run system performance test.