Expansion Valve: Service and Repair

Thermal Expansion Valve Replacement

Tools Required

J 39400-A Halogen Leak Detector

Removal Procedure

Important: Cap or tape the open evaporator inlet and outlet tubes immediately in order to prevent system contamination.





1. Recover the refrigerant from the air conditioning (A/C) system. Refer to Refrigerant Recovery and Recharging (Refrigerant Recovery and Recharging).
2. Reposition the heater hoses for clearance, if necessary.
3. Remove the evaporator tube block to the thermal expansion valve (TXV) nut.
4. Disconnect the evaporator inlet and outlet tube block from the TXV.
5. Remove the evaporator inlet tube from the outlet tube.
6. Remove and discard the sealing washers.
7. Cap or tape off the evaporator inlet and outlet tubes.




8. Remove the TXV to evaporator bolts.
9. Remove the TXV from the evaporator core.
10. Remove and discard the TXV sealing washers.

Installation Procedure




1. Install NEW sealing washers onto the evaporator core.
2. Install the TXV to the evaporator core.

Notice: Refer to Fastener Notice (Fastener Notice).

3. Install the TXV to evaporator bolts.

Tighten the bolts to 3.2 N.m (28 lb in).




4. Remove the caps or tape from the evaporator inlet and outlet tubes.
5. Install NEW sealing washers onto the inlet and outlet tubes.
6. Install the evaporator inlet tube to the outlet tube.
7. Connect the evaporator inlet and outlet tube block to the TXV.
8. Install the evaporator tube block to the TXV nut.

Tighten the bolts to 16 N.m (12 lb ft).

9. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging (Refrigerant Recovery and Recharging).
10. Leak test the fittings using the J 39400-A.