Refrigerant Capacity

Note: The vehicle should not be exposed to sunshine before and during test.

1. Test tension of V-belt for compressor drive.






Layout of pressure switch in receiver dehydrator:
17 Pressure switch for refrigerant compressor

2. Engage air conditioning system and watch through sight glass (refer to arrow, Fig.) in receiver dehydrator whether the refrigerant flows free of bubbles shortly after switching on electromagnetic clutch. Add refrigerant if system is insufficiently filled. In the event of a refrigerant loss above 200 g. check system for leaks.






3. Open fresh air center and side vent (21). Close side vent (22).
4. Mount a thermometer for outside air temperature (ambient temperature) approx. 2 m from driver's side.






5. Place a hygrometer into tray of center console.
6. Connect suction and pressure gauges to service valves.
7. Plug one thermometer each into center jet and lateral jet at left.
8. Open windows and rear passenger compartment vent. Close vehicle doors and engine hood.






9. Temperature dial engaged in "MIN" position. Push blower switch (f) 6th stage.
10. Push function selection button "c" and run engine at approx. 2000/rpm.






Layout control unit:
3 Temperature dial
4 Pushbutton switch with 5 functions
5 Blower switch

11. Read data on thermometers and pressure gauges, as well as on hygrometer, after an operating period of approx. 10 minutes and compare with values on table.

Note: Specified data are max. data and should not be exceeded.






Engine 110:
1) Relative humidity
ta Outside temperature (°C)
A Air outlet temperature (°C)
B Pressure before compressor (bar)
C Pressure after compressor (bar)
D Coolant temperature (°C)






Engine 116, 117:
1) Relative humidity
ta Outside temperature (°C)
A Air outlet temperature (°C)
B Pressure before compressor (bar)
C Pressure after compressor (bar)
D Coolant temperature (°C)






12. Check cutout temperature of ETR-switch (29) and/or evaporator temperature sensor (B 10/6) by inserting a thermometer into the center outlet. Push blower switch (h) 1st stage, press key (c) in control unit and run engine at approx. 2000 rpm. When the electromagnetic clutch cuts out for the 3rd time, the outlet temperature should be approx. + 4 °C, but must not be less than + 3 °C.






Note: If cooling capacity is insufficient, check that capillary of ETR-switch (29) or evaporator temperature sensor (B 10/6) is correctly installed or replace switch or sensor if necessary.