Refrigerant Circuit Cleaning Process

WARNING: This page is about a different car, the 2024 Audi S6 and 2024 Audi A6 Quattro. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

The progress takes place automatically according to the A/C Service Station program. Refer to the A/C Service Station Owner's Manual.

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 A/C Service Station, it may be necessary to manually advance through the program).
After the refrigerant circuit is checked for seals after evacuating, the flushing circuit/refrigerant circuit is checked for correct assembly by filling a specific quantity of refrigerant.
After the pressure test, the refrigerant is extracted, the refrigerant circuit is evacuated again if necessary, and the cleaning (the flushing process) begins.
A prescribed quantity of refrigerant (depending on the internal volume of the flushing circuit for example 3 kg (6.61 lbs)) is filled into the refrigerant circuit via the high pressure side of the A/C Service Station (in opposite direction of normal flow when A/C system is in operation and also on the low pressure side of the vehicle refrigerant circuit), or, as much refrigerant is filled until refrigerant circuit and viewing glasses of refrigerant circuit flushing device are completely filled with fluid refrigerant (depending on version of A/C Service Station, recognized for example that refrigerant no longer flows over a certain time period).
After the prescribed quantity of refrigerant has been filled, the heater for the refrigerant circuit flushing device is switched on, for example (only if the refrigerant is extracted in gaseous form from the refrigerant circuit flushing device), depending on the version of the A/C Service Station and refrigerant circuit flushing device.
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 A/C Service Station separates the refrigerant oil extracted from the refrigerant circuit.
The sequence of charging, extracting (and evacuating) the refrigerant is repeated three times (performed a total of four times).
After the fourth extraction, the flushing circuit is evacuated depending on the version of the A/C Service Station.