Expansion Valve and Receiver (With Internally Regulated Compressor), Checking

Expansion Valve and Receiver (With Internally Regulated Compressor), Checking

NOTE:
- Connect service station.Working With Service Station
- Observe test conditions. Pressures In Refrigerant Circuit, Checking (Using Service Station)

- Set engine speed to 2000 RPM.
- Observe pressure gauge set.

NOTE: Switching pressures and arrangement of refrigerant circuit switches are vehicle-specific.

Pressures must be measured at service connections; component locations of these connections are vehicle-specific

Specified values:

High pressure side:
Increasing from initial pressure (on connecting pressure gauges) to max. 20 bar.

Low pressure side:







Decreasing from initial pressure (on connecting pressure gauges) to value in graph.
A - High pressure in bar
B - Low pressure in bar
C - Permissible tolerance range.







NOTE: If no malfunction can be found and air conditioner operation is not OK when test is repeated, flush refrigerant circuit with compressed air and nitrogen.







If operation is not Ok after refrigerant circuit has been flushed, expansion valve must be replaced.







NOTE: Always replace receiver for this malfunction.







NOTE: If the function of the air conditioning system is not OK when the test is repeated, re-install old expansion valve and flush refrigerant circuit with compressed air and nitrogen. Then replace A/C compressor and receiver.












NOTE:
- If the function of the air conditioning system is not OK when the test is repeated, re-install old expansion valve and flush refrigerant circuit with compressed air and nitrogen. Then replace A/C compressor and receiver.
- With this malfunction, evaporator may ice up although quantity of refrigerant in circuit is 0K.







NOTE: Overfilling with refrigerant oil can occur if, for example, the compressor has been replaced without adjusting the quantity of refrigerant oil.