GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Lumina VE 🢒 HVAC 🢒 Heating, Ventilation, and Air Conditioning 🢒 Flushing

Tools Required

    •  R-134a - A/C Tracer Dye Box of 24
    •  Universal 12 V Leak Detection Lamp
    •  Air Conditioning Service Centre
    •  A/C Flush Adapter Kit

The A/C system and in particular the heat exchangers (evaporator and condenser) will need to be flushed (cleaned internally) if the following issues have occurred:

    • A/C system "over lubricated". This normally occurs after a compressor has been replaced and the oil balancing procedure has not been carried correctly. This condition shows up as an extremely high high pressure (HP) reading.
    • Contamination such as aluminium particles in the A/C system which cause blockages in the condenser, receiver dehydrator and TX valve. The most common component causing contamination through the A/C system is a compressor that has internally collapsed.

Flush Procedure

    Important: It is imperative that all safety rules and first aid is followed for the specific flushing solvent being used. Consult with your solvent supplier and ask for an MSDS (Material Safety Data Sheet) which will outline all safety precautions.

  1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging .

    2. Important:  The recommended method of flushing is the open loop. Read the instructions regarding health, safety and environmental issues prior to commencing the flushing procedure.

  2. Remove the compressor. Refer to Air Conditioning Compressor Replacement .
  3. Drain all the oil through the compressor drain plug then through the rear hose pad ports. DO NOT flush through the compressor.

    4. Important: It is important to follow the process found in Receiver Dehydrator Replacement for correct removal of receiver dehydrator

    Important: DO NOT reuse the receiver dehydrator after removal.

  4. Remove the receiver dehydrator.

    5. Discard the receiver dehydrator

    Important: Place the TX valve in a plastic bag to avoid any contamination from air born dirt or moisture.

  5. Disconnect all hose/pipe fittings from the TX valve. Refer to Air Conditioning Evaporator Thermal Expansion Valve Replacement . Refer to Air Conditioning Condenser Replacement .
  6. Remove the TX valve. Refer to Air Conditioning Evaporator Thermal Expansion Valve Replacement .
  7. Fill the flushing vessel with solvent. Connect the pressure hose and the flush gun handle to the outlet side of the component being flushed.
  8. Connect a clear plastic hose (simply wedge the hose in place or use worm drive clips) to the outlet port for discharging solvent waste to the collection container.
  9. Connect the solvent container to a pressure source such as dry workshop compressed air or dry Nitrogen (NO2). This pressure is required to force the solvent through the A/C components.
  10. Activate flush gun and force solvent through the component.
  11. On the same component being flushed, reverse direction flush.
  12. View through the clear plastic discharge hose to see when the liquid become clear, this indicates the level of cleanliness of the component internals. Repeat this operation on the evaporator, condenser, hoses and pipes.
  13. After flushing is finished, allow 30 minutes with the system still open to atmosphere, to "boil off" any solvent residue left in the components. Then reconnect all parts using NEW sealing washers.
  14. Add the total specified amount of PAG oil (used for the complete system) to the compressor, through the drain plug and by turning the front pulley.