Expansion Valve: Service and Repair

Expansion Valve

Special tools, testers and auxiliary items required

• Torque Wrench (V.A.G 1331)

• Robinair A/C Service Unit (ROB 134APF) or newer model

• Engine Bung Set (VAS 6122)

There is a danger of ice-up.

Refrigerant leaks out if refrigerant circuit is not discharged.

Refrigerant must be extracted before opening the refrigerant circuit. If the refrigerant circuit is not opened within 10 minutes after extracting it, pressure may build up in the circuit again. The refrigerant must be extracted again.

• The expansion valve atomizes the streaming refrigerant and controls the flow quantity so that the vapor is gaseous only at the evaporator outlet, depending on the heat transmission.

• Extract the refrigerant using the (ROB 134APF) (or succeeding model).

• Environmentally hazardous draining of refrigerant is an offense punishable by law.

• See notes, refer to => [ Repairing Vehicles Equipped with A/C and Handling Refrigerants ] Repairing Vehicles Equipped with A/C and Handling Refrigerants.

• Depending on engine and version of vehicle, it may be necessary to loosen or to remove the following components: top engine cover, pressurized air pipe to throttle valve part and depending on engine the intake manifold, etc.

Removing

- Extract the refrigerant with the (ROB 134APF) (or newer models) from the refrigerant circuit.

• The heat shield is installed in front of the expansion valve, depending on engine.

• Loosen, but do not remove, the heat shield and pull it off slightly. The coolant system does not need to be opened.

If equipped, loosen the heat shield

- Remove nut - 1 - (10 Nm).

- Remove the lock washer - 2 - and the clip - 3 -.

- Loosen the heat shield for the expansion valve - 4 - from the bulkhead.






All vehicles

- Remove the refrigerant line - 2 - bolts - 1 - (10 Nm).

- Carefully remove the refrigerant lines - 2 - from the expansion valve - 4 -.

- Remove the expansion valve - 4 - bolts - 8 - (5 Nm).

- Carefully remove the expansion valve - 4 - from the heater and A/C unit.






Installing

Install the expansion valve in reverse order. Note the following when doing this:

• Always replace the O-ring for the high pressure refrigerant line - 3 and 5 -.

• Always replace the O-ring for the low pressure refrigerant line - 6 and 7 -.

• Lubricate O-ring seal lightly with refrigerant oil before installing.