Volkswagen Workshop Service and Repair Manuals

Notes:

• ◆ Refrigerant must be evacuated with Service station V.A.G 1885 first.
• ◆ The previously used service stations can still be used =>Binder Volkswagen Workshop Equipment.
• ◆ Adhere to the instructions concerning safety measures when working on a refrigerant circuit which has been evacuated .
• ◆ Only the components marked with an * can be replaced without opening and evacuating.
• ◆ To prevent the ingress of dampness all components of the refrigerant circuit which have been opened must be sealed with suitable plugs.

• ◆ The colour coding of O-rings for the R134a refrigerant circuits has been discontinued. Coloured and black O-rings are used.

• Expansion valve
• ◆ Engine compartment right
• ◆ Opening must be sealed sufficiently to stop ingress of water
• ◆ Removing

Function

• ◆ The expansion valve atomizes the instreaming refrigerant and regulates the through flow so that the vapour, depending on temperature, becomes a gas only on reaching the outlet side of the evaporator.
• ◆ The expansion valves for R134a refrigerant circuits are marked with a green sticker.

• O ring
• ◆ 14 mm; 1.8 mm
• Evaporator
• ◆ In passenger compartment
• ◆ Removing => Page 87-165 , Dismantling and assembling housing
• O ring
• ◆ 10.8 mm; 1.8 mm
• O ring
• ◆ 7.6 mm; 1.8 mm
• Evacuating and charging valve
• ◆ High pressure side
• ◆ Evacuatingthe refrigerant into the environment is a punishable offence.
• ◆ Removing and installing => Fig.2
• ◆ Capacities => Page 87-168

• Socket head screw
• ◆ M6X20
• ◆ 7 Nm
• Sight glass
• Compressor
• ◆ With magnetic coupling -N25-
• O ring
• ◆ 20.5 mm; 1.8 mm
• ◆ Qty. 2
• Combi bolt
• ◆ M10X32
• ◆ 30 Nm
• O ring
• ◆ 10.8 mm; 1.8 mm
• 3/4" thread - 17 UNF
• ◆ 35 Nm

• Pressure relief valve
• ◆ Checking => Fig.3
• Condenser
• ◆ Removing => Page 87-162
• 5/8" thread - 18 UNF
• ◆ 15 Nm
• O ring
• ◆ 7.6 mm; 1.8 mm
• 3/4" thread - 16 UNF
• ◆ 35 Nm
• O ring
• ◆ 10.8 mm; 1.8 mm
• O ring
• ◆ 10.8 mm; 1.8 mm

• Fluid container with drier
• ◆ Tasks => Fig. 4
• 5/8" thread - 18 UNF
• ◆ 15 Nm
• O ring
• ◆ 7.6 mm; 1.8 mm

• Air conditioner pressure switch -F129-*
• ◆ Removing and installing:
• ‒ Tightening torque 8 Nm
• ‒ Renew O ring seal (note Part No.).
• ◆ Pressure switch can be removed without evacuating refrigerant from system.
• ◆ Checking air conditioner pressure switch -F129- => Page 87-145
• Function:
• ◆ Switches radiator fan -V7- to next higher speed when pressure increases in refrigerant circuit.
• ◆ Switches off conditioning system when pressure is excessive (for example, insufficient engine cooling).
• ◆ Switches off conditioning system when pressure is too low (for example, loss of refrigerant).

• Compressor magnetic coupling -N25-
• ◆ Manufacturer: Sanden
• Carrying out repairs on the magnetic coupling, with the compressor installed, should only be undertaken in exceptional circumstances.
• ◆ Servicing magnetic coupling with compressor removed => Page 87-152 .
• Oil filling/draining plug
• Evacuating and charging valve
• ◆ Low pressure side
• ◆ Evacuatingthe refrigerant into the environment is a punishable offence.
• ◆ Removing and installing => Fig.1
• ◆ Capacities => Page 87-168
• O ring
• ◆ 16.7 mm; 1.8 mm

→ Fig.1     Removing evacuating and charging valve, low pressure side

• ‒ Extract refrigerant circuit with Service station V.A.G 1885 and then renew the valve -3-.

For further Service stations => Binder Volkswagen Workshop Equipment.

Notes:

• ◆ Draining the refrigerant into the environment is a punishable offence.
• ◆ To prevent the ingress of dampness all components of the refrigerant circuit which have been opened must be sealed with suitable plugs.

•      1 -     Connection with external thread and groove for O-ring
•      2 -     O-ring
• 7.6 mm; 1.8 mm
•      3 -     Extraction and filling valve
•      4 -     O-ring
• 7.6 mm; 1.8 mm
•      5 -     Cap

→ Fig.2     Removing evacuating and charging valve, high pressure side

• ‒ Extract refrigerant circuit with Service station V.A.G 1885 and then renew the valve -3-.

For further Service stations => Binder Volkswagen Workshop Equipment.

Notes:

• ◆ Draining the refrigerant into the environment is a punishable offence.
• ◆ To prevent the ingress of dampness all components of the refrigerant circuit which have been opened must be sealed with suitable plugs.

•      1 -     Connection with internal thread
•      2 -     O-ring
• 10.8 mm; 1.8 mm
•      3 -     Extraction and filling valve with groove and internal thread for cap.
•      4 -     O-ring
• 10.8 mm; 1.8 mm
•      5 -     Cap

→ Fig.3     Checking pressure relief valve on compressor

• ◆ Task: protects refrigerant circuit against excessive pressures
• ◆ The pressure relief valve tell-tale indicates if the valve has operated. A small plate attached by adhesive will be pushed out.

→ Fig.4     Tasks of reservoir and dryer

The fluid reservoir collects the liquid droplets and guides them in a continuous stream to the expansion valve. Moisture, which has entered the refrigerant circuit during assembly is collected by the dryer in the reservoir.

Note:

The fluid reservoir must be renewed each time the refrigerant circuit is opened.

→ Checking pressure switch for air conditioner -F129-

• ◆ The pressure switch can be removed without extracting the refrigerant from the refrigerant circuit.
• ◆ Visual check: Ensure that O-ring 10.8 mm x 1.8 mm is seated in groove

Switch part between chamber 1 and 2 of connector housing switches magnetic coupling -N25- off when refrigerant circuit is insufficiently filled or pressure is too high.

• ‒ Opens below 1.2 bar and closes again above 2.4 bar (switching threshold)
• ‒ Opens above 32 bar and closes again below 24 bar (switching threshold)

→ Checking switch part:

• ‒ Briefly bridge circuit between chambers 1 and 2 with engine running. If the magnetic coupling -N25- switches on, the refrigerant system is empty.

Switch part between chamber 3 and chamber 4 of connector housing switches radiator fan -V7- via radiator fan control unit -J293- to 2nd speed when refrigerant pressure rises.

• ‒ Closes above 16 bar and opens below 12.5 bar (switching threshold)

Evaluating the checks on the pressure switch for the air conditioner -F129-

• ◆ The following checks are performed when installed.

→ To assess the air conditioning system output perform and evaluate the following checks:

• ‒ Check condition of filling, the air conditioner system is switched off when pressure is too low (for example when refrigerant is lost).
• ‒ Check blower switch-on, the radiator fan -V7- is switched to the next highest speed when pressure in the refrigerant circuit rises.
• ‒ Check air conditioner switch-off, the air conditioner is switched off when pressure is excessive (for example when engine cooling is insufficient).