Flushing Circuit With E-Compressor

If an E-compressor is being replaced that does not have a mechanical fault (for example, a faulty circuit board), then determine how much refrigerant is in it.

Quantity: for example 50 cm³

A new E-compressor is filled with 150 cm³ refrigerant oil.

-- Pour 90 cm³ out of the new E-compressor. 10 cm³ is extra.

Fig 1: Identifying Flushing Circuit With E-Compressor Diagram

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

1. A/C service station 
   NOTE:

   Flushing the E-compressor is performed manually.

   -- Extract the refrigerant, if necessary.

   -- Empty the Service Station old oil container.

   NOTE:

   On some Service Stations, the oil is first separated in the vacuum phase and then it goes into the old oil container.

   -- Set the amount of refrigerant on the Service Station to 2 kg and the oil quantity to 0.

   -- Set up the Refrigerant circuit flushing device VAS 6336/1 or Refrigerant circuit flushing device VAS 6337/1A between the service station and refrigerant circuit return line.

   -- Evacuate the refrigerant circuit for 10 minutes. Then observe the vacuum display. If the vacuum remains constant, then fill the circuit with 2 kg refrigerant R134a. Then extract again and repeat the procedure one more time.

2. Refrigerant Hose Of A/C Service Station 
   • From low pressure side of A/C service station (mostly colored blue) to output of refrigerant circuit flushing device.
3. Refrigerant Circuit Flushing Device 
   • Different versions and different construction, for example, Refrigerant circuit flushing device VAS 6336/1 or Refrigerant circuit flushing device VAS 6337/1.
   • With filter, viewing glass, security valve, heater, refrigerant container, etc. (depending on version).
   • Depending on the construction of the A/C service station and of refrigerant circuit flushing device, a check-valve may be installed at output of refrigerant circuit flushing device (to guarantee correct direction of refrigerant flow during flushing).
4. Charge Hose For Refrigerant Circuit Flushing Device 
   • From connection to high pressure side of A/C compressor on refrigerant circuit (smaller diameter) to input of Refrigerant Circuit Flushing Device VAS 6336/1 or Refrigerant Circuit Flushing Device VAS 6337/1.
5. Adapter To Connection For High Pressure Side On Refrigerant Circuit 
   • From VW/Audi passenger vehicle set adapter chest VAS 6338/1 adapter number 6338/3.
6. Refrigerant Line, High Pressure Side, From The E-Compressor 

   -- Remove the centering pin.

7. E-compressor 
8. Refrigerant Line, Low Pressure Side, To The E-Compressor 

   -- Remove the centering pin.

9. Adapter To Connection For Low Pressure Side On Refrigerant Circuit 
   • From VW/Audi passenger vehicle set adapter chest VAS 6338/1 adapter number 6338/6.
10. Refrigerant Hose Of A/C Service Station 
    • From the high pressure side of the service station (mostly red) to the connection on the low pressure line above the engine to the E-compressor