Operation CHARM: Car repair manuals for everyone.

Filling Air-Conditioning System




Filling air-conditioning system

1. All procedures described so far must have been carried out, i.e., the system must be evacuated, flushed, evacuated once more, and must be sealed.

2. Close all valves on service unit. The filling cylinder must contain sufficient refrigerant; if not, refill.

3. To fill the system, there must be positive pressure of approx. 7 bar in the filling cylinder. To reach this pressure, switch on the filling cylinder heating.





Note: A pressure rise of 1 bar takes approx. 10 minutes.




4. Depending on the value displayed on the pressure gauge (e.g. 7 bar), set the filling cylinder scale so that the value indicated on the upper edge of the scale comes to rest over the viewing glass.




It should be noted that this scale is designed for use with more than one refrigerant. The refrigerant designations are found on the lower edge of the scale.
For automotive air-conditioning systems, only the scales for R 12 can be used.

5. Set the required refrigerant quantity on the filling cylinder with the sliding ring (difference from previous refrigerant level).

6. Again check to see that all valves - particularly the torrmeter cutoff valve 14 - are closed.

7. Open the filling valve 2 and high pressure valve 6.

8. Observe the fluid display in the viewing glass of the filling cylinder. When the level of liquid has reached the setting ring, close valve 2. Open filling valve 9 for a short period, in order to force the quantity remaining in fill hose into the air-conditioning system. Close high-pressure valve

9. Switch off heating. Disconnect fill hoses from compressor. Screw protective cap on to valves.