Expansion Valve: Service and Repair

Expansion Valve

NOTE: The illustrations in this service information are used for different model years and/or models. Some variation may occur. However, the essential information in the illustrations is always correct.

Preparatory work

Draining the air conditioning (A/C) system

WARNING: Follow the safety instructions for work on air conditioning systems. See: Refrigerant

CAUTION: Always use new O-rings lubricated with compressor oil.

NOTE: Plug the pipes and connections when working on the climate control system.

Drain the refrigerant from the air conditioning (A/C) system. See: Refrigerant, draining.

Removing the expansion valve (orifice)





Clean the join thoroughly.
Slacken off the cap nut.

NOTE: Make a note of the position of the expansion valve in the pipe.

Pull or work out the expansion valve. See the illustration.
It is not screwed in place.

HINT: The expansion valve can be removed using round-nosed pliers.

CAUTION: Make sure that the expansion valve does not come off.

Inspecting the filter section of the expansion valve (A) shows an approved expansion valve.





(A) shows an approved expansion valve.

If 4 or 5 filter sections in the expansion valve are clogged (B) , the compressor oil must be inspected.

If the filter is extremely clogged or if it contains a large volume of metal particles, the compressor may need to be replaced.

If the compressor oil is black or very dirty, replace the compressor.
If the compressor is dry, replace the compressor.

Installation

Installing the expansion valve (orifice)

Install a new expansion valve.

NOTE: Make sure that the expansion valve is properly pressed into the pipe section at the evaporator.

Install the cap nut. Tighten. See: Tightening torque.

Finishing

Checking the function and leak tracing

Vacuum pump the air conditioning (A/C) system. See: Vacuum pumping.
Fill the air conditioning (A/C) system with refrigerant. See: Refrigerant, filling.
Leak trace the air conditioning (A/C) system. See: Leak detection, tracer agent or: Leak tracing, electronic leak tracer.

Checking the performance

Carry out a performance test on the climate control unit. See: Climate control system, check.