Q: How to properly service the A/C Expansion Valve on a GMC Envoy?
A: The procedure to replace a thermal expansion value begins by removing the Evaporator core auxiliary followed by eliminating foam insulators from Evaporator core auxiliary lines and thermal expansion value auxiliary. Begin by loosening the flare nuts from the thermal expansion valve-auxiliary using a back up wrench before removing its sensing bulb that comes with a retaining clip from the Evaporator core-auxiliary lines. After removing the thermal expansion valve-auxiliary, carefully take it out of the Evaporator core-auxiliary before disposing of its o-ring seals while using caps or tape to seal the lines from Evaporator core-auxiliary contamination. Uncover the Evaporator core-auxiliary lines by removing their cap or tape to start installation while adding new o-rings and attaching the thermal expansion valve-auxiliary to these lines. The installation of foam insulators on both the thermal expansion valve-auxiliary and Evaporator core-auxiliary lines proceeds with back up wrench settings for 5 n.m (44 lb in).
Q: How to replace the A/C Expansion Valve on GMC Canyon?
A: The replacement process for a thermal expansion valve (TXV) requires recovering refrigerant beforehand. To begin the process remove the TXV mounting stud's nut before you separate the evaporator tube from the TXV and detach the compressor suction hose from the same valve. The technician should discard the old seal washers while removing the TXV bolts prior to extracting the TXV. After fitting new seal washers on the evaporator core fittings you should position the TXV. Secure the TXV bolts with a torque of 7 N.m while following the installation procedure (62 lb in). The procedure continues with fitting new sealing washers on both the evaporator tube and the compressor suction hose before refitting these components to the TXV. Secure the TXV nut afterward by tightening it to 20 N.m (15 lb ft). The system requires evacuation and charging before performing Halogen Leak Detector-based (J39400-A) fittings check.
Q: How to replace the A/C Expansion Valve in the auxiliary system on GMC Savana 2500?
A: Begin the thermal expansion valve replacement in the auxiliary system by removing the Evaporator core followed by a gentle seal removal procedure around the txv where the mounting position and tube orientation on the core need to be noted. After you remove the capillary tube clip from the Evaporator core you must disconnect txv connections from the Evaporator tubes before taking out the txv from the core. When installing the txv position it onto the core before connecting the Evaporator tubes to the valve with torques set to 28 n.m (21 lb ft). The clip will secure the capillary tube to the Evaporator core before the pack sealer application enables a wrapping of the txv just as in disassembly steps and completion of Evaporator core reinstallation.