Ford Motor Company has approved a procedure to provide technicians with a non-CFC method of flushing contaminated A/C system heat exchangers, A/C evaporator core, and A/C condenser core. The procedure allows the specific 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 or desiccant failure within the suction accumulator and gummy residue that can 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 Flush and Purge Machine 219-00022 to:
- Discharge the A/C system. Observe all safety precautions. For additional information, refer to the procedure in this section.
- Disconnect the refrigerant lines from the heat exchanger(s) to be flushed.
- Connect the A/C Flush and Purge Machine 219-00022 and A/C Flush and Purge Fitting Kit 219-00024 to the heat exchanger to be flushed. Do not flush through the evaporator core orifice, mufflers or hoses. Internal plumbing and material make-up of these components make it impossible to correctly remove foreign material or residual flushing solvent.
- Use one gallon (3.785 liters) of A/C Systems Flushing Solvent part number F4AZ-19579-A 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.
- Flush the component for a minimum of 15 minutes.
Apply 90-125 psi (621-862 kPa) pressurized air to the component for a minimum of 30 minutes. The 30-minute purge time is required to force and evaporate all residual 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 the used flush solvent and filter in accordance with local, state and federal emissions.
NOTEA/C system filtering as described in this section is optional if system flushing is carried out. However, the filter kit use is recommended after flushing if the A/C system contamination is extensive.
- Install a new evaporator core orifice in any vehicle being serviced for A/C compressor or desiccant failure.
- Install new refrigerant hoses if clogged with foreign material.
- Reconnect the heat exchanger being serviced.
- Add additional refrigerant oil as required. For additional information, refer to the procedure in this section.
- Evacuate, leak test and charge the A/C system. For additional information, refer to the procedure in this section.
- Check the system for normal operation.