Expansion Valve: Service and Repair

THERMAL EXPANSION VALVE (TXV)

REMOVAL

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

1. Recover refrigerant using an approved refrigerant recovery system. Measure the amount of oil lost during recovery and record.

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

NOTE: When removing the TXV, keep dirt and foreign material from getting on or into the O-ring sealing surfaces. Clean tools and a clean work area are important for proper service. The TXV seal area should be cleaned before any repairs are performed. The parts must be kept clean at all times and any parts to be assembled should be cleaned with a non-petroleum based solvent and dried with air. Use only lint free cloths to wipe parts. Do not allow solvent to enter evaporator or hoses.

IMPORTANT: On earlier vehicles a bolt was used instead of a stud/nut.




2. Remove suction/liquid line block-to-TXV retaining nut.
3. Remove suction/liquid line block from TXV by gently rocking while pulling forward.
4. Install cap on suction/liquid line assembly to prevent oil spillage.




5. Remove TXV retaining bolts




6. On earlier vehicles, install suction/liquid line assembly to TXV bolt hand tight into TXV.




7. Using bolt or stud as a handle, remove TXV from evaporator by gently rocking TXV while pulling forward in vehicle.




8. Using fingers or a plastic tool, remove O-rings from evaporator pipes. Use a mirror to view O-rings on evaporator core.

INSTALLATION




1. Install new O-rings to evaporator pipes.




2. Turn ignition On and select outside air on control head
3. Disconnect negative battery cable.




4. Remove wiper arm assemblies.




5. Remove cowl retaining nuts and remove cowl screen assembly.




6. Rotate two locking tabs outward to release filter assembly.
7. Remove filter by lifting straight up.




8. Remove wiper motor retaining bolts and slide wiper motor assembly to the right.




9. Remove four filter housing attachment bolts and remove filter housing.




10. Remove four blower motor housing screws, release locking tabs and remove fan housing.
11. Disconnect blower motor electrical connector by squeezing bottom of connector and pulling downward.
12. Remove blower motor assembly by lifting straight out.

IMPORTANT: On earlier vehicles a bolt was used instead of a stud/nut.




13. Hand tighten suction/liquid line assembly to TXV stud into TXV. The stud will be used to aid installation.




14. Apply a thin coating of clean mineral oil on TXV to evaporator O-ring surfaces.

CAUTION: BLOWER RESISTOR CARD HAS SHARP EDGES AND MAY BE VERY HOT IF BLOWER WAS USED PRIOR TO SERVICING.

15. Reach down through blower motor opening and locate evaporator pipes and block.
16. Install TXV into foam seal, dome end towards passenger's side of vehicle.
17. While gently lifting evaporator pipes and block with one hand, gently press TXV inward until fully installed onto both pipes. When completely installed, TXV should be almost flush with edge of bevel of TXV foam seal.




18. Remove suction/liquid line assembly to TXV bolt from TXV.

NOTE: Improper installation of TXV to evaporator pipes will damage pipes and require evaporator core replacement.

19. Thread TXV to evaporator core block bolts into block by hand. Bolts should thread in easily. Do not force! If bolts do not thread in easily, verify that TXV is properly installed onto both pipes and fully seated to block.
20. After verifying proper installation, tighten both TXV to block bolts.

Torque:
TXV-to-Block Bolts: 7 N.m (62 in-lbs)




21. Thoroughly clean the O-ring surfaces of the TXV.
22. Install new O-rings to suction/liquid line assembly block.
23. Lubricate the O-rings with clean mineral oil.
24. Install suction/liquid line assembly block to TXV.

IMPORTANT: On earlier vehicles a retainer bolt was used instead of a stud/nut.

25. Install suction/liquid line assembly to TXV nut.

Torque:
Suction/Liquid Line Assembly-to-TXV Bolt: 7 N.m (62 in-lbs)




26. Install blower motor assembly into module housing. Fan motor assembly rib must be located into channel in module housing.
27. Connect blower motor electrical connector.
28. Install blower motor housing. Housing rib must fit into slot in module case. Snap left and right clip into place and install fan housing to module screws.

NOTE: A new filter housing seal must be used whenever the filter housing is removed to prevent water from leaking into module.




29. Remove filter housing seal using a small flat blade screwdriver.
30. Install new filter housing seal.




31. Install filter housing and four screws.

Torque:
Filter Housing-to-HVAC Module Fasteners: 3.5 N.m (31 in-lbs)




32. Reposition wiper motor assembly and install wiper motor bolts.

Torque:
Wiper Motor Bolts to Wiper Motor Assembly: 5 N.m (44 in-lbs)




33. Install cabin air filter paying special attention to air flow direction indicator printed on side of filter.
34. Rotate two locking tabs on filter housing inward to secure air filter in place.




35. Install cowl screen and fasteners.
36. Close the filter access door.




37. Install wiper arm assemblies.

Torque:
Wiper Arm Assembly Nuts: 20 N.m (15 ft-lbs)

38. Connect negative battery cable.

Torque:
Battery Terminal Bolts: 17 N.m (151 in-lbs)

39. Evacuate, charge, and leak check the A/C system.