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Heating, Ventilation and Air Conditioning: Maintenance GMC Envoy II

Automatic HVAC System ~1534 words

Flushing (Front Only System)

Tools Required

  1. J 43600 ACR 2000 Air Conditioning Service Center. See «Special Tools»(ref-200405-S14942364402005102000000) .
  2. J 45268 Flush Adapter Kit. See «Special Tools»(ref-200405-S14942364402005102000000) .
  3. J 41447 Leak Detection Dye. See «Special Tools»(ref-200405-S14942364402005102000000) .
  4. J 42220 Universal 12V Leak Detection Lamp. See «Special Tools»(ref-200405-S14942364402005102000000) .
IMPORTANTFlushing with the ACR 2000 is not intended to remove metal from the A/C system.

Flushing is intended to remove the following contaminants

  1. Contaminated polyalkylene glycol (PAG) oil
  2. Desiccant, following a desiccant bag failure
  3. Overcharge of PAG oil
  4. Refrigerant contamination
  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(ref-200405-S26753095092005102000000) .
  2. Remove the orifice tube. Refer to «Expansion (Orifice) Tube Replacement (Front Only System)»(ref-200405-S10006329132005102000000) or «Expansion (Orifice) Tube Replacement (Auxiliary System)»(ref-200405-S35514764342005102000000) .
  3. Connect the A/C lines with the orifice tube removed.
  4. Remove the A/C compressor. Refer to «Compressor Replacement (LL8)»(ref-200405-S26366460982005102000000) or «Compressor Replacement (LM4)»(ref-200405-S36676275322005102000000) .
  5. Install J 45268-2 to the A/C compressor hose assembly.
  6. Forward flow refrigerant flushing is recommended for contaminated refrigerant or PAG oil. Perform the following procedure: IMPORTANT: The filter inside J 45268-1 is serviceable. Remove and discard the check valve from the filter. Service the filter with ACDelco P/N GF 470, before each flush. Connect J 45268-1 to the suction port of J 45268-4 flush adapter. Connect the blue hose from J 43600 to J 45268-1. See «Special Tools»(ref-200405-S14942364402005102000000) . Connect the red hose from J 43600 to J 45268-5. See «Special Tools»(ref-200405-S14942364402005102000000) .
  7. Reverse flow refrigerant flushing is recommended for desiccant bag failure only. Perform the following procedure and replace the accumulator when the flush is complete: IMPORTANT: The filter inside J 45268-1 is serviceable. Remove and discard the check valve from the filter. Service the filter with ACDelco P/N GF 470, before each flush. Connect J 45268-1 to the discharge port of J 45268-5. Connect the blue hose from J 43600 to J 45268-1. See «Special Tools»(ref-200405-S14942364402005102000000) . Connect the red hose from J 43600 to the suction port of J 45268-4. See «Special Tools»(ref-200405-S14942364402005102000000) .
  8. Flush the front A/C system. Follow the instructions supplied with the J 43600 . See «Special Tools»(ref-200405-S14942364402005102000000) .
  9. Remove J 45268-4 from the A/C compressor hose assembly.
  10. If you will reinstall the removed A/C compressor, perform the following procedure: Remove the A/C compressor drain plug. Drain the PAG oil from the A/C compressor. Rotate the compressor input shaft to assist in draining the PAG oil from the compressor. NOTE: Refer to «Fastener Notice»(ref-200361-S03298564292005102000000) in Cautions and Notices. Install the A/C compressor drain plug. Tighten: Tighten the drain plug to 20 N.m (15 lb ft). Add the total system capacity of PAG oil to the A/C compressor. Refer to «Refrigerant System Capacities»(ref-200405-S33665552472005102000000) .
  11. If you will replace the A/C compressor after flushing the system, perform the following procedure: Determine if the new service compressor is shipped with PAG oil. Refer to the «Refrigerant System Capacities»(ref-200405-S33665552472005102000000) . The service compressor is shipped with PAG oil, DO NOT drain the new PAG oil from the compressor. Deduct the amount of PAG oil shipped with the service compressor from the amount of PAG oil listed in the capacities table. Refer to «Refrigerant System Capacities»(ref-200405-S33665552472005102000000) . Add the calculated amount to the compressor, as needed.
  12. Add one bottle of J 41447 directly to the A/C compressor. See «Special Tools»(ref-200405-S14942364402005102000000) .
  13. Install the A/C compressor. Refer to «Compressor Replacement (LL8)»(ref-200405-S26366460982005102000000) or «Compressor Replacement (LM4)»(ref-200405-S36676275322005102000000) .
  14. Inspect the orifice tube for debris. Clean or replace as needed.
  15. Install the orifice tube. Refer to «Expansion (Orifice) Tube Replacement (Front Only System)»(ref-200405-S10006329132005102000000) or «Expansion (Orifice) Tube Replacement (Auxiliary System)»(ref-200405-S35514764342005102000000) .
  16. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(ref-200405-S26753095092005102000000) .
  17. Leak test the fittings using J 42220 . See «Special Tools»(ref-200405-S14942364402005102000000) .

Flushing (Auxiliary System)

Tools Required

  1. J 43600 ACR 2000 Air Conditioning Service Center. See «Special Tools»(ref-200405-S14942364402005102000000) .
  2. J 45268 Flush Adapter Kit. See «Special Tools»(ref-200405-S14942364402005102000000) .
  3. J 41447 Leak Detection Dye. See «Special Tools»(ref-200405-S14942364402005102000000) .
  4. J 41459 Leak Detection Dye Injector. See «Special Tools»(ref-200405-S14942364402005102000000) .
  5. J 42220 Universal 12V Leak Detection Lamp. See «Special Tools»(ref-200405-S14942364402005102000000) .
IMPORTANTFlushing with the ACR 2000 is not intended to remove metal from the A/C system.

Flushing is intended to remove the following contaminants

  1. Contaminated polyalkylene glycol (PAG) oil
  2. Desiccant, following a desiccant bag failure
  3. Overcharge of PAG oil
  4. Refrigerant contamination
  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(ref-200405-S26753095092005102000000) .
  2. Remove the orifice tube. Refer to «Expansion (Orifice) Tube Replacement (Front Only System)»(ref-200405-S10006329132005102000000) or «Expansion (Orifice) Tube Replacement (Auxiliary System)»(ref-200405-S35514764342005102000000) .
  3. Connect the A/C lines with the orifice tube removed.
  4. Remove the A/C compressor. Refer to «Compressor Replacement (LL8)»(ref-200405-S26366460982005102000000) or «Compressor Replacement (LM4)»(ref-200405-S36676275322005102000000) .
  5. Inspect the end of the suction hose for a suction screen.
  6. Remove the suction screen, if installed.
  7. Install J 45268 -2 to the A/C compressor hose assembly. See «Special Tools»(ref-200405-S14942364402005102000000) .
  8. Forward flow refrigerant flushing is recommended for contaminated refrigerant or PAG oil. Perform the following procedure: IMPORTANT: The filter inside J 45268-1 is serviceable. Remove and discard the check valve from the filter. Service the filter with ACDelco P/N GF 470, before each flush. Connect J 45268 -1 flush filter to the suction port of J 45268 -2 flush adapter. See «Special Tools»(ref-200405-S14942364402005102000000) . Connect the blue hose from J 43600 to J 45268 -1 flush filter adapter. See «Special Tools»(ref-200405-S14942364402005102000000) . Connect the red hose from J 43600 to J 45268 -2 flush adapter. See «Special Tools»(ref-200405-S14942364402005102000000) .
  9. Reverse flow refrigerant flushing is recommended for desiccant bag failure. Perform the following procedure and replace the accumulator when the flush procedure is complete. IMPORTANT: The filter inside J 45268 -1 is serviceable. See «Special Tools»(ref-200405-S14942364402005102000000) . Remove and discard the check valve from the filter. Service the filter with ACDelco P/N GF 470, before each flush. Connect J 45268 -1 flush filter to the discharge port of J 45268 -2 flush adapter. See «Special Tools»(ref-200405-S14942364402005102000000) . Connect the blue hose from J 43600 to J 45268 -1 flush filter adapter. See «Special Tools»(ref-200405-S14942364402005102000000) . Connect the red hose from J 43600 to the suction port of J 45268 -2 flush adapter. See «Special Tools»(ref-200405-S14942364402005102000000) .
  10. Flush the front A/C system. Follow the instructions supplied with the J 43600 . See «Special Tools»(ref-200405-S14942364402005102000000) .
  11. If the vehicle is equipped with rear A/C, flush the auxiliary A/C system separately.
  12. Cut the orifice tube frame and screen, enough to access the end of the orifice tube. Pinch off the orifice tube.
  13. Install the pinched orifice tube. Refer to «Expansion (Orifice) Tube Replacement (Front Only System)»(ref-200405-S10006329132005102000000) or «Expansion (Orifice) Tube Replacement (Auxiliary System)»(ref-200405-S35514764342005102000000) .
  14. Remove the auxiliary TXV. Refer to «Thermal Expansion Valve Replacement - Auxiliary»(ref-200405-S04863929212005102000000) .
  15. Install J 45268 -108. See «Special Tools»(ref-200405-S14942364402005102000000) .
  16. Install the auxiliary evaporator core to the A/C lines.
  17. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-200385-S41061932852005102000000) in General Information.
  18. Connect the auxiliary A/C lines to the auxiliary evaporator core.
  19. Lower the vehicle.
  20. Flush the auxiliary A/C system. Follow the instructions supplied with the J 43600 . See «Special Tools»(ref-200405-S14942364402005102000000) .
  21. Raise the vehicle. Refer to «Lifting and Jacking the Vehicle»(ref-200385-S41061932852005102000000) in General Information.
  22. Remove the auxiliary A/C lines from the auxiliary evaporator core.
  23. Lower the vehicle.
  24. Remove J 45268 -108. See «Special Tools»(ref-200405-S14942364402005102000000) .
  25. Inspect the TXV for debris. Clean or replace as needed.
  26. Install the auxiliary TXV. Refer to «Thermal Expansion Valve Replacement - Auxiliary»(ref-200405-S04863929212005102000000) .
  27. Remove J 45268 -2 from the A/C compressor hose assembly. See «Special Tools»(ref-200405-S14942364402005102000000) .
  28. If the removed A/C compressor is being reinstalled, perform the following procedure: Remove the A/C compressor drain plug. Drain the PAG oil from the A/C compressor. Rotate the compressor input shaft to assist in draining the PAG oil from the compressor. Install the A/C compressor drain plug. Tighten: Tighten the drain plug to 20 N.m (15 lb ft). Add the total system capacity of PAG oil to the A/C compressor. Refer to «Refrigerant System Capacities»(ref-200405-S33665552472005102000000) .
  29. If you replace the A/C compressor after flushing the system, perform the following procedure: Determine if the new service compressor is shipped with PAG oil. Refer to the «Refrigerant System Capacities»(ref-200405-S33665552472005102000000) . If the service compressor is shipped with PAG oil, DO NOT drain the new PAG oil from the compressor. Deduct the amount of PAG oil shipped with the service compressor from the amount of PAG oil listed in the capacities table. Refer to «Refrigerant System Capacities»(ref-200405-S33665552472005102000000) . Add the calculated amount to the compressor, as needed. If the service compressor is shipped dry, no calculation is required. Add the total system capacity of PAG oil to the compressor. Refer to «Refrigerant System Capacities»(ref-200405-S33665552472005102000000) .
  30. Add one bottle of J 41447 directly to the A/C compressor. See «Special Tools»(ref-200405-S14942364402005102000000) .
  31. Install the A/C compressor. Refer to «Compressor Replacement (LL8)»(ref-200405-S26366460982005102000000) or «Compressor Replacement (LM4)»(ref-200405-S36676275322005102000000) .
  32. Install a new orifice tube. Refer to «Expansion (Orifice) Tube Replacement (Front Only System)»(ref-200405-S10006329132005102000000) or «Expansion (Orifice) Tube Replacement (Auxiliary System)»(ref-200405-S35514764342005102000000) .
  33. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(ref-200405-S26753095092005102000000) .
  34. Leak test the fittings using J 42220 . See «Special Tools»(ref-200405-S14942364402005102000000) .

Draining Procedure

  1. Drain the oil from both the suction and discharge ports of the removed compressor into a clean, graduated container. Rotate the compressor shaft to assist in draining the compressor.
  2. Measure and record the amount of oil drained from the removed compressor. This measurement will be used during installation of the replacement compressor.
  3. Properly discard the used refrigerant oil.

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