Rear Expansion Valve

NOTE:

After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side).

-- Disconnect refrigerant lines from rear expansion valve, refer to REAR EXPANSION VALVE, DISCONNECTING AND CONNECTING .

-- Remove bolts -A- (tightening torque 10 Nm).

Fig 1: Identifying Expansion Valve, Removal

Courtesy of AUDI OF AMERICA, LLC

-- Pull off expansion valve -B-.

NOTE:

Seal all open lines and connections on evaporator with suitable caps (to protect from damaged and avoid dirt and moisture from entering the system).

Installing

Installation is carried out in the reverse order while noting the following:

-- Replace O-rings -D- and -E-.

-- Make sure that O-ring seals -C- and -D- are properly seated on connecting pipes to evaporator.

NOTE:

Expansion valve is available in different versions (same housing but a different control characteristic).

Coat the O-ring seals lightly with refrigerant oil prior to installation, refer to REFRIGERANT CIRCUIT O-RINGS .

The retaining plate -E- is installed on the connecting pipes. Make sure they are seated correctly when installing the expansion valve.

-- Place expansion valve -B- on to connections on evaporator.

-- Install bolts -B- (tightening torque 10 Nm).

-- Connect refrigerant lines for rear expansion valve, refer to REAR EXPANSION VALVE, DISCONNECTING AND CONNECTING .

-- Install remaining components.

-- Evacuate and re-charge refrigerant circuit. Refer to OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

-- Operate the A/C system after filling the refrigerant circuit, refer to OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

NOTE:

Note the information regarding operating the A/C system after filling in OPERATING AFTER FILLING REFRIGERANT CIRCUIT .

-- If necessary, check the function of the A/C system using Vehicle Diagnosis, Testing and Information System VAS 5051 in "Guided Fault Finding" function.