Air Conditioning (A/C) System Flushing
Air Conditioning (A/C) System Flushing
1. WARNING: Use extreme care and observe all safety precautions related to the use of refrigerants. Warning: Due to refrigerant hazards, always wear safety goggles and non-penetrable gloves when working on or flushing A/C systems. Failure to follow this instruction may result to personal injury.
CAUTION:
- The A/C refrigerant analyzer must be used before the recovery of any vehicle's A/C refrigerant. Failure to do so puts shop bulk refrigerant at risk of contamination. If the vehicle A/C refrigerant is contaminated, refer the customer to return to the repair facility that performed the last A/C repair. If the customer wishes to pay the additional cost, use the A/C recovery equipment that is designated for recovering contaminated A/C refrigerant. All contaminated A/C refrigerant must be disposed of as hazardous waste. For all equipment, follow the equipment manufacturers procedures and instructions. Failure to follow this instruction may result to personal injury.
- Suction accumulator/drier, muffler, hoses, thermal expansion valve, and fixed orifice tube should be removed when flushing the A/C system. Internal plumbing of these devices makes it impossible to correctly remove any residual flushing agent. Except for the hoses, these components are typically discarded after A/C system contamination. Hoses can normally be reused unless they are clogged with debris. The flushing solvent and filter used in the A/C Flusher are intended for use on one vehicle only. They may be used to flush both the A/C condenser core and the A/C evaporator core on an individual vehicle, but under no circumstances should they be used on more than one vehicle.
NOTE: Prior to using A/C Flusher for the first time, review its operating instructions. Failure to follow this instruction may result to personal injury.
This procedure allows the specified components to be cleaned and flushed while installed in their normal in-vehicle location. The types of contamination flushed include particle matter that results from A/C compressor and/or desiccant failure within the suction accumulator/drier and gummy residue that may form when refrigerant oil is overheated during A/C compressor seizure. The flushing process is a two-step procedure that involves the use of an A/C Flusher to:
- Circulate the flushing solvent through the heat exchanger in the reverse direction of normal refrigerant flow (backflushing). Particulate matter picked up during flushing is filtered from the returning solvent before the solvent is returned to the reservoir for continued circulation.
- Remove the flushing solvent from the heat exchanger. In this step of the procedure, pressurized air 621 - 862 kPa (90 - 125 psi) is used to push and/or evaporate any remaining flush solvent from the heat exchanger.
2. Reclaim the refrigerant. For additional information, refer to.
3. Disconnect refrigerant lines from the heat exchanger(s) to be flushed.
4. Connect A/C flusher and A/C flusher fitting kit to the heat exchanger to be flushed. Do not flush through the A/C evaporator core orifice, mufflers or lines. Internal plumbing and material make-up of these components make it impossible to correctly remove debris and/or residual flushing solvent.
5. Use flushing solvent to flush the heat exchanger for a minimum of 15 minutes. The flush solvent may be used for one or both heat exchangers in the A/C system. However, the flush solvent is intended for one vehicle only. The filter used on the flushing unit is also intended for use on one vehicle only.
6. Flush component for a minimum of 15 minutes.
7. Apply 621 - 862 kPa (90 - 125 psi) pressurized air to the component for a minimum of 30 minutes. The 30 minute purge time is required to force and/or evaporate all residual flush solvent from the A/C system component. Failure to successfully remove all residual solvent within the component can result in system damage when reconnected and operated. Dispose of used flush solvent and filter in accordance with local, state and federal ordinances.
8. NOTE: A/C system filtering as described in this section is optional if system flushing is performed. However, filter kit use is recommended after flushing if A/C system contamination is extensive.
Install new suction accumulator/drier and A/C evaporator core orifice on any vehicle being repaired for A/C compressor or desiccant failure.
9. Install new refrigerant lines if clogged with debris.
10. Reconnect the heat exchanger being flushed.
11. Add additional refrigerant oil as required. For additional information, refer to.
12. Evacuate, charge and leak test A/C system.
13. Check A/C system for correct operation.