Refrigerant Circuit Cleaning Process

WARNING: This page is about a different car, the 2022 Volkswagen ID.4 and 2021 Volkswagen ID.4. However, it is still accessible from the selected car via links, so may be relevant.

The procedure automatically runs according to the A/C Service Station program for R1234yf or R134a. Refer to the A/C Service Station Operating Instructions.

After turning on, the flushing circuit (refrigerant circuit with connecting hoses and refrigerant circuit flushing device) is evacuated first and the refrigerant circuit is checked for leaks at the same time (depending on the version of the R1234yf or R134a A/C Service Station, it may be necessary to manually advance through the program).
Depending on the A/C Service Station, and after the refrigerant circuit was checked for leaks by evacuating it, the flushing/refrigerant circuit is now checked for correct assembly (pressure test) by adding a specific small amount of refrigerant. Refer to the A/C Service Station Operating Instructions.
After the pressure test, the refrigerant is extracted, the refrigerant circuit is evacuated again if necessary, and the cleaning (the flushing process) begins.
A specified amount of refrigerant (depends on the flushing circuit internal volume, for example 6 kg (13.23 lbs)) is added to the refrigerant circuit via the high-pressure side of an R1234yf or R134a A/C Service Station (with the normal flow direction during A/C system operation; meaning, on the high-pressure side of the vehicle refrigerant circuit), or so much refrigerant is added until the refrigerant circuit and the refrigerant circuit flushing device sight glasses are completely filled with liquid refrigerant (depending on the version of the R1234yf or R134a A/C Service Station, it detects when there is no longer any refrigerant flowing in after a certain amount of time, for example). Refer to the A/C Service Station Operating Instructions.
After the prescribed quantity of refrigerant has been added, for example, the heater for the refrigerant circuit flushing device is switched on (only if the refrigerant is extracted in its gaseous form from the refrigerant circuit flushing device), depending on the version of the R1234yf or R134a A/C Service Station and the refrigerant circuit flushing device. Refer to the A/C Service Station Operating Instructions.
After the refrigerant has been extracted, the heater on the refrigerant circuit flushing device is switched off (if equipped). Depending on the version, the refrigerant circuit may be briefly evacuated again. After evacuating, the R1234yf or R134a A/C Service Station separates the refrigerant oil extracted from the refrigerant circuit.
The process of filling the refrigerant and extracting (and evacuating) is repeated two or three more times; performed three or four times in total (depending on the R1234yf or R134a A/C Service Station). More information can be found in the operating instructions for the A/C Service Station. Refer to the A/C Service Station Operating Instructions.
Depending on the version of the R1234yf or R134a A/C Service Station, the flushing circuit is evacuated after the third or fourth extraction.