Sequence Of Flushing Procedure
Sequence of flushing procedure (sequence occurs automatically according to the A/C service station program)
- After switching on, the flushing circuit (refrigerant circuit with connecting hoses and refrigerant circuit flushing device) is first evacuated and the refrigerant circuit is simultaneously checked for leaks. Depending on A/C service station version, it is possible that manually switching to advance the program is required.
- A prescribed amount of refrigerant (for example 9lb. (4 kg)) is filled into the evacuated flushing circuit via the high pressure side of the A/C service station (opposite the normal direction of flow during normal A/C system operation and thus on the low pressure side of vehicle refrigerant circuit). Depending on the version of the A/C service station, refrigerant is added until the flushing circuit is completely full. This can be detected by refrigerant no longer flowing in after a certain period of time.
- After the prescribed quantity of refrigerant has been filled, for example. the heater for the refrigerant circuit flushing device is switched on (only in the event the refrigerant is extracted in gaseous form from the refrigerant circuit flushing device), depending on version of A/C service station and refrigerant circuit flushing device.
- After the refrigerant has been extracted, the heater on the refrigerant circuit flushing device (if applicable) switches off, the refrigerant circuit may be evacuated again (depending on the version), and the refrigerant oil extracted from the refrigerant circuit is separated by the A/C service station after evacuating.
- The sequence of filling refrigerant, extracting (and evacuating) is repeated twice (performed a total of three times).
- After the third extraction, the flushing circuit is evacuated depending on the version of the A/C service station.
-- After the flushing cycle has ended, check the viewing glass(es) on the flushing device. If they are dirty, clean them according to the instructions for the flushing device or A/C service station. Perform one addition flushing cycle as a check. One flushing procedure is sufficient (approximately 30 min.)
-- Check pressure in refrigerant circuit, there must be no positive pressure in the refrigerant circuit (evacuate refrigerant circuit briefly once more if necessary).
-- Disconnect A/C service station connections from vehicle refrigerant circuit. There must be no positive pressure in the refrigerant circuit.
-- Replace these vehicle-specific components.
- Restrictor and reservoir
- Expansion valve and fluid reservoir or dryer cartridge in fluid reservoir
-- Refer to [For engine(s) BLV, CCTA, CBFA] Description and Operation .
-- Depending on the complaint, replace A/C compressor. Refer to [For engine(s) BLV, CCTA, CBFA] Removal and Installation or drain the remaining refrigerant oil from the removed A/C compressor. Refer to COMPONENT REPLACEMENT (replace refrigerant circuit components) and re-fill the prescribed quantity of fresh refrigerant oil. Refer to Maintenance, Diagnosis .
A certain prescribed quantity of refrigerant oil is in the A/C compressor original part. On vehicles with two evaporators, a certain quantity of refrigerant oil must also be added to the circuit if necessary. Refer to Maintenance, Diagnosis .
If the A/C compressor is not replaced, the quantity of refrigerant oil in the A/C compressor must be topped off to the prescribed capacity (tilt the refrigerant oil out and refill the prescribed quantity into the A/C compressor or refrigerant circuit). Refer to COMPONENT REPLACEMENT and Maintenance, Diagnosis .
-- Completely reassemble the refrigerant circuit. Refer to [For engine(s) BLV, CCTA, CBFA] Removal and Installation .
-- Evacuate and recharge refrigerant circuit according to specification. Refer to REFRIGERANT CIRCUIT, DISCHARGING WITH SERVICE STATION and REFRIGERANT CIRCUIT, CHARGING WITH SERVICE STATION .
-- Start up A/C system according to specification. Refer to [For engine(s) BLV, CCTA, CBFA] General Information and A/C SYSTEM, OPERATING AFTER CHARGING .