Home/GMC/Sierra 3500/GMC Sierra 3500 (2002-2006)/Repair manual/Automatic HVAC System/Heating, Ventilation and Air Conditioning: Maintenance
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Heating, Ventilation and Air Conditioning: Maintenance GMC Sierra 3500

Automatic HVAC System 2 illustrations ~522 words

Flushing

Tools Required

  1. J 41447 Leak Detection Dye. See «Special Tools and Equipment»(ref-184172-S42637868852005082200000) .
  2. J 42220 Universal 12V Leak Detection Lamp. See «Special Tools and Equipment»(ref-184172-S42637868852005082200000) .
  3. J 43600 ACR 2000 Refrigerant Station. See «Special Tools and Equipment»(ref-184172-S42637868852005082200000) .
  4. J 45268 Flush Adapter Kit. See «Special Tools and Equipment»(ref-184172-S42637868852005082200000) .
IMPORTANTFlushing is not intended to remove metal from the A/C system.

Flushing is intended to remove the following

  1. Contaminated PAG oil
  2. Desiccant, following a desiccant bag failure
  3. Overcharge of PAG oil
  4. Refrigerant contamination

Scheme 77

Scheme 77
  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(ref-184172-S07266075792005082200000) .
  2. Remove the orifice tube. Refer to «Expansion (Orifice) Tube Replacement»(ref-184172-S11100477292005082200000) .
  3. Connect the A/C lines with the orifice tube removed.
  4. Remove the A/C compressor. Refer to «Compressor Replacement (L18)»(ref-184172-S36134357292005082200000) , «Compressor Replacement (LB7)»(ref-184172-S08881900412005082200000) or «Compressor Replacement (LR4, LM7, and LQ4)»(ref-184172-S04348428702005082200000) .
  5. Install J 45268-3 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 flush filter to the suction port of the J 45268-3 flush adapter. Connect the blue hose from the J 43600 to J 45268-1 flush filter adapter. Connect the red hose from the J 43600 to J 45268-3 .
  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 the 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 the J 45268-1 flush filter to the discharge port of J 45268-3 flush adapter. Connect the blue hose from J 43600 to J 45268-1 flush filter adapter. Connect the red hose from J 43600 to the suction port of J 45268-3 .
  8. Flush the A/C system. Follow the instructions supplied with the J 43600 .
  9. Remove the J 45268-3 from the A/C compressor hose assembly.
  10. Drain the PAG oil from the A/C compressor. Rotate the compressor input shaft to assist in draining the PAG oil from the compressor.
  11. Add back the total system capacity of PAG oil to the A/C compressor. Refer to «Refrigerant System Capacities»(ref-184172-S38558511072005082200000) .
  12. Add one bottle of J 41447 directly to the A/C Compressor.
  13. Install the A/C compressor. Refer to «Compressor Replacement (L18)»(ref-184172-S36134357292005082200000) , «Compressor Replacement (LB7)»(ref-184172-S08881900412005082200000) or «Compressor Replacement (LR4, LM7, and LQ4)»(ref-184172-S04348428702005082200000) .
  14. Inspect the orifice tube for debris. Clean or replace as needed.
  15. Install the orifice tube. Refer to «Expansion (Orifice) Tube Replacement»(ref-184172-S11100477292005082200000) .
  16. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(ref-184172-S07266075792005082200000) .
  17. Leak test the fittings using the J 42220 .

Scheme 78

Scheme 78: Draining
  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.