Servicing components of refrigerant circuit — VW

Engine code AGL=>Page
87-48

Note:

The refrigerant must be evacuated beforehand with the service station V.A.G 1885.
The service stations used up until now may continue to be used
=> V.A.G Workshop Equipment folder.
Dafety measures when working on the evacuated refrigerant circuit =>Page
87-1
, Notes on repair work on air conditioned vehicles and on handling refrigerant
Components marked with * can be renewed without opening and evacuating.

All opened components of the refrigerant circuit must be sealed off against the entrance of moisture with suitable sealing plugs.
The coloured marking of the O-rings for refrigerant circuits with R134a is no longer used. Now black and coloured
O-rings are used.

Evaporator
In passenger compartment
Removing => Page
87-89
, Dismantling and assembling evaporator housing

Refrigerant lines
From evaporator to expansion valve

O-ring
14 mm; 2 mm

O-ring
10.6 mm; 2 mm

Expansion valve
In right of engine compartment
Passage must be splash-water-proof
Removing => Page
87-65

Tasks

The expansion valve atomises refrigerant flowing in and controls the feed rate so that the vapour first becomes gaseous at the outlet in dependence on the heat transport.
The expansion valves for refrigerant circuits with refrigerant R134a are marked with a green adhesive label.

Allen screw
5 Nm

O-ring
7.6 mm; 1.8 mm

O-ring
17.2 mm; 1.8 mm

Refrigerant line
From expansion valve to compressor

Hexagon nut
10 Nm

O-ring
10.8 mm; 1.8 mm

Evacuating and filling valve
Low-pressure side
It is punishable by law to drain off refrigerant into the environment.
Removing and installing =>Fig.
1
Capacities => Page
87-95

Protective cap*

Refrigerant line
From receiver with drier to expansion valve

Thread 5/8" - 18 UNF
17 Nm

O-ring
7.6 mm; 1.8 mm

Receiver with drier
Tasks => Fig.
2

Pressure switch for air conditioner -F129-*
Removing and installing:

Tightening torque 8 Nm
Replacing O-ring seal (observe spare part number).

The pressure switch can be removed without having to evacuate the refrigerant from the refrigerant circuit.
Testing pressure switch for air conditioner -F129- => Page
87-62

Function:

Switches coolant fan -V7- to next highest speed when pressure increases in refrigerant circuit.
Switches the air conditioner off when the pressure is too high (for example, in the case of insufficient engine cooling).
Switches the air conditioner off when the pressure is too low (for example, in the case of coolant loss).

Note:

A pressure switch can also be fitted at this fitting location, which only consists of one instead of two switches:

=> Current flow diagrams, electrical fault finding and fitting locations folder

O-ring
10.8 mm; 1.8 mm

O-ring
7.6 mm; 1.8 mm

Thread 5/8" - 18 UNF
17 Nm

Protective cap*
Evacuating and filling valve
High-pressure side
It is punishable by law to drain off refrigerant into the environment.
Removing and installing =>Fig.
1
Capacities => Page
87-95

O-ring
12.8 mm; 1.8 mm

Refrigerant line
Front receiver with drier to condenser

Thread 5/8" - 18 UNF
17 Nm

O-ring
7.6 mm; 1.8 mm

O-ring
14 mm; 1.8 mm

Condenser
Removing => Page
87-86

Combi hex bolt
Thread 7/8" - 14 UNF
30 Nm

Refrigerant hose
From compressor to condenser

O-ring
14.3 mm; 2.4 mm

Magnetic coupling -N25- of compressor
Manufacturer: Sanden

Repairs to the magnetic coupling for which the compressor remains installed should only be carried out in exceptional cases.

Servicing magnetic coupling with compressor removed: => Seite
87-69
.

Kompressor
with magnetic coupling -N25-
Manufacturer: Sanden
Table of compressor manufacturers: => Seite
87-61

Überdruckablaßventil
prüfen=>Seite
87-60

O-Ring
10.8 mm; 1.8 mm

Cheese head screw
20 Nm

Refrigerant line
From expansion valve to compressor

Cheese head screw
20 Nm

Allen screw
5 Nm

O-ring
10.8 mm; 1.8 mm

O-ring
14 mm; 1.8 mm

Engine codeAGL

Evaporator
In passenger compartment
Removing => Page
87-89
, Dismantling and assembling evaporator housing

Refrigerant lines
From evaporator to expansion valve

O-ring
14 mm; 2 mm

O-ring
10.6 mm; 2 mm

Expansion valve
In right of engine compartment
Passage must be splash-water-proof
Removing => Page
87-65

Tasks

The expansion valve atomises refrigerant flowing in and controls the feed rate so that the vapour first becomes gaseous at the outlet in dependence on the heat transport.
The expansion valves for refrigerant circuits with refrigerant R134a are marked with a green adhesive label.

Allen screw
5 Nm

O-ring
7.6 mm; 1.8 mm

O-ring
17.2 mm; 1.8 mm

Refrigerant line
From expansion valve to compressor

Hexagon nut
10 Nm

O-ring
10.8 mm; 1.8 mm

Evacuating and filling valve
Low-pressure side
It is punishable by law to drain off refrigerant into the environment.
Removing and installing =>Fig.
1
Capacities => Page
87-95

Protective cap*
Refrigerant line
From receiver with drier to expansion valve

Thread 5/8" - 18 UNF
15 Nm

O-ring
7.6 mm; 1.8 mm

Receiver with drier
Tasks => Fig.
2

Pressure switch for air conditioner -F129-*
Removing and installing:

Tightening torque 8 Nm
Replacing O-ring seal (observe spare part number).

The pressure switch can be removed without having to evacuate the refrigerant from the refrigerant circuit.
Testing pressure switch for air conditioner -F129- => page
87-62

Function:

Switches coolant fan -V7- to next highest speed when pressure increases in refrigerant circuit.
Switches the air conditioner off when the pressure is too high (for example, in the case of insufficient engine cooling).
Switches the air conditioner off when the pressure is too low (for example, in the case of coolant loss).

Note:

A pressure switch can also be fitted at this fitting location, which only consists of one instead of two switches:

=> Current flow diagrams, electrical fault finding and fitting locations folder

O-ring
10.8 mm; 1.8 mm

O-ring
7.6 mm; 1.8 mm

Thread 5/8" - 18 UNF
15 Nm

Protective cap*
Evacuating and filling valve
High-pressure side
It is punishable by law to drain off refrigerant into the environment.
Removing and installing =>Fig.
1
Capacities => Page
87-95

O-ring
12.8 mm; 1.8 mm

Refrigerant line
Front receiver with drier to condenser

Thread 5/8" - 18 UNF
15 Nm

O-ring
7.6 mm; 1.8 mm

Condenser
Removing => Page
87-86

Coolant fan -V7-*
Fastened to condensor with 3 bolts

Combi hex bolt
Radiator

Thread 7/8" - 14 UNF
30 Nm

O-ring
14 mm; 1.8 mm

Refrigerant hose
From compressor to condenser

Cheese head screw
20 Nm

O-ring
11.1 mm; 1.8 mm

Cheese head screw
20 Nm

Pressure relief valve
Checking=>Page
87-60

Magnetic coupling -N25- of compressor
Manufacturer: Denso

Repairs to the magnetic coupling for which the compressor remains installed should only be carried out in exceptional cases.

Servicing magnetic coupling with compressor removed: => page
87-79
.

Compressor
With magnetic coupling -N25-
Manufacturer: Denso
Table of compressor manufacturers: => page
87-61

O-ring
23.8 mm; 2.4 mm

Cheese head screw
20 Nm

Allen screw
5 Nm

O-ring
10.8 mm; 1.8 mm

O-ring
14 mm; 1.8 mm

Fig.1
Removing evacuating and filling valves, high and low-pressure side

First evacuate refrigerant circuit with service station
V.A.G 1885, then renew valves.

For other service stations => V.A.G Workshop Equipment folder.

Note:

It is punishable by law to drain off refrigerant into the environment.
All opened components of the refrigerant circuit must be sealed off against the entrance of moisture with suitable sealing plugs.

1 -
O-ring
12.8 mm; 1.8 mm

2 -
High-pressure valve
3 -
Cap of high-pressure valve
4 -
Cap of low-pressure valve
5 -
Low-pressure valve
6 -
O-ring
10.8 mm; 1.8 mm

When installing valves, moisten sealing rings with oil and lay in groove (arrow) of valves.

Fig.2
Tasks of receiver with drier

The receiver collects the liquid drops and then carries them in a continuous stream to the expansion valve. Moisture which has entered the refrigerant circuit during assembly is trapped in the receiver by a drier.

Note:

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