Electrically-Driven A/C Compressor, Cleaning

Vehicles with High-Voltage System

Observe all of the additional warnings for all work performed on vehicles with the high-voltage system. Refer to SAFETY PRECAUTIONS WHEN WORKING ON THE HIGH-VOLTAGE SYSTEM .

If it is necessary to perform work in the vicinity of high-voltage system components, "visually inspect" the high-voltage components and cables for damage and follow the "High-Voltage System General Warnings". Refer to SAFETY PRECAUTIONS WHEN WORKING ON THE HIGH-VOLTAGE SYSTEM .

If it is necessary to perform work on the high-voltage system components, de-energize the high-voltage system (refer to [For engine(s) DPVA] High-Voltage System, De-Energizing ) and observe the "High-Voltage System General Warnings" (refer to SAFETY PRECAUTIONS WHEN WORKING ON THE HIGH-VOLTAGE SYSTEM ).

Flush the A/C compressor

Fig 1: Flush The Electrically Driven A/C Compressor Diagram

Courtesy of AUDI OF AMERICA, LLC

1. A/C Service Station
   • Use electronics and a program to flush the A/C Service Station with flushing device. Refer to the Parts Information.
   • If an A/C Service Station without a flushing program is used, the procedure must be performed manually (evacuate, flush four times with at least 2 kg (4.41 lbs) refrigerant for each and extract the refrigerant again, evacuate).
2. Refrigerant Hose for A/C Service Station
   • From the high pressure side of the A/C Service Station (mostly red colored) to the low pressure side connection of the A/C compressor on refrigerant circuit (larger diameter).
3. Adapter to the Connection for the Low Pressure Side on the A/C Compressor
   • There are different versions depending on vehicle. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .
   • Use the Refrigerant Circuits Adapter Set - Adapter 48:VAS 6338/48  between the refrigerant hose -2- and the adapter -3-.
   • From the VW/Audi - Passenger Vehicle Adapter Set (for example the Adapter: VAS 6338/41  )
4. Refrigerant Line
   • To the A/C compressor connection on the adapter  ELECTRICALLY-DRIVEN A/C COMPRESSOR, CLEANING List Item:Adapter to the Connection for the Low Pressure Side on the A/C Compressor
5. Electrically-Driven A/C Compressor
   • The A/C compressor is flushed in the flow direction (from the low pressure side input to the high pressure side output)
   • So that as much refrigerant oil as possible is flushed out from the A/C compressor, the A/C compressor must be positioned so that the high pressure side output is as low as possible
     NOTE:

     Depending on the A/C compressor a larger refrigerant oil quantity can be filled in a new A/C compressor (refer to the manufacturer label on the A/C compressor and Refer to REFRIGERANT OIL CAPACITIES ).

     On a new A/C compressor that is filled with more than 100 cm³ , pour out as much refrigerant oil as possible before flushing.

     Reason: depending on the A/C Service Station version, the oil amount that is deposited/separated in one step may be limited.

     NOTE:

     If clean refrigerant oil is emptied from a new A/C compressor in a clean container and this is closed air tight, this can be reused to adjust the refrigerant oil quantity in the circuit.

6. Refrigerant Line
   • To the A/C compressor connection on the adapter  ELECTRICALLY-DRIVEN A/C COMPRESSOR, CLEANING List Item:Adapter to the High Pressure Side Connection on the Refrigerant Circuit
   • To remove the flushing circuit use for example a refrigerant line with the part number 7L6 820 721 BF. Refer to the Parts Information.
7. Adapter to the High Pressure Side Connection on the Refrigerant Circuit
   • There are different versions depending on vehicle. Refer to ADAPTER FOR ASSEMBLING FLUSHING CIRCUIT .
   • From the VW/Audi - Passenger Vehicle Adapter Set (for example the Adapter: VAS 6338/40  )
8. Charging Hose for Refrigerant Circuit Flushing Device
   • From the connection to the high pressure side of the A/C compressor on the refrigerant circuit (smaller diameter) to the input of the refrigerant circuit flushing device.
9. Refrigerant Circuit Flushing Device
   • There are different versions of the Refrigerant Circuit Flushing Device. Refer to the Parts Information (Tools; Special Tools and Equipment: A/C and Heating).
   • With filter, viewing glass, safety valve, heater, refrigerant reservoir, etc. (depending on version).
   • Depending on the design of the A/C Service Station and the flushing device for the refrigerant circuits, a connection for a service coupling for the refrigerant circuits can be installed on the output and may also be installed on the input of the flushing device. If a service connection with a valve is installed on the outlet of the flushing device, this valve must be all the way open when the service coupling is attached. A partially opened valve creates a constriction.
   • If on the input of the flushing device a connection for a service coupling is present, modify the input so that the refrigerant hose which comes from the vehicle can be directly connected.
     NOTE:

     A service coupling and a valve in the flushing device input makes a constriction which impairs the refrigerant flow from the vehicle in the flushing device.

10. Refrigerant Hose for A/C Service Station
    • From the low pressure side of the A/C Service Station (mostly blue colored) to the output of the refrigerant circuit flushing device.