Repairing refrigerant circuit — AUDI

Note:

The spare compressor contains all the refrigerant oil to be used to fill the refrigerant circuit (135 cm3).
Check refrigeration capacity => Page
87-80
.
No refrigerant may be filled into the refrigerant circuit (empty system, evacuate and re-fill).
The specified diameters for the O-ring seals and the tightening torque also apply to the screwed connections in the refrigerant pipes or hoses between the individual components.
Adapter to connect the service station to the refrigerant circuit.

=> Air Conditioner with Refrigerant R134a

Depending upon the engine version, it may be necessary to remove the dome strut and the associated bracket, so that the service coupling can be attached to the service connection
Only install O-ring seals approved for refrigerant R134a (present colour coding: "red", "lilac" or "violet").

=> Parts List

Servicing the refrigerant circuit => Page
87-11
.
Checking pressures in the refrigerant circuit :

=> Air Conditioner with Refrigerant R134a

All other repairs and tests not described in this workshop manual

=> Air Conditioner with Refrigerant R134a

The "Air Conditioner with Refrigerant R134a" Workshop Manual can be found in "the workshop information" under "Internet" (globe), "Audi" (flag with your language), "Technical Information" (arrow).

HD = High-pressure side

ND = Low-pressure side

Oil drain plug
O-ring seal:
8.8 mm; 1.5 mm (colour: black)
Tightening torque:
15 Nm

Notes:

To drain refrigerant oil:

Remove compressor.
Remove oil drain plug.
Crank compressor via the magnetic clutch disc to accelerate extraction of oil.

Air conditioner magnetic clutch -N25
Repairing => Page
87-11
.

Compressor
Disconnecting and connecting refrigerant lines =>Page
87-107

Removing and installing compressor bracket

=> Engine, Mechanical Components; Repair group 13
Engine, Mechanical Components

Removing and re-attaching compressor from/to bracket

4-cyl. petrol engine=>Page
87-21
.
6-cyl. engine=>Page
87-23
.

Removing and installing compressor =>Page
87-108

Notes:

Removing and installing poly V-belt.

=> Engine,Mechanical Components; Repair group 13
Engine,Mechanical Components

Mark direction of poly V-belt before removing - reversing the direction of rotation can destroy the belt.
The piston stroke of the compressor is variable and automatically adjusts to the requisite refrigeration capacity.

After the installation of a new compressor or filling with fresh refrigerant oil (e.g. after blowing out the refrigerant circuit), turn the compressor 10 revolutions by hand before the first start to avoid damage to the compressor.

Pressure relief valve
O-ring seal:
8.6 mm; 1.8 mm (colour: black).
Tightening torque: 10 Nm

Note:
The connection is not fitted with a valve; only remove pressure relief valve when refrigerant circuit is empty.
Condenser
Removing and installing => Page
87-102
.

Fluid reservoir
Removing and installing => Page
87-100
.

Service connection
High-pressure side.
For measuring, draining and filling at service station.

Note:
The service connections may be removed only if the refrigerant circuit is empty - the connection is not supplied with a valve.
Note:

Depending upon the engine and the vehicle version, it may be necessary to remove the dome strut in order to be able to attach the service coupling to the service connection.

Cap
With seal, must always be fitted.

Connection with valve
Air conditioner pressure switch -F129 / high-pressure sender -G65
The high pressure sender -G65 gradually replaces the air conditioner pressure switch -F129.
Function, removing and installing pressure switch -F129 => Page
87-16
.

Check function of high-pressure sender -G65 and signal emitted =>Page
01-157
.
Removing and installing high-pressure sender -G65 =>Page
87-19

Expansion valve
Disconnecting and connecting refrigerant lines =>Page
87-105
.
Removing and installing =>Page
87-106
.
Removing and installing heat insulation =>Page
87-54

Evaporator
Removing and installing air conditioner => Page
87-111
.
Dismantling and assembling air-conditioner => Page
87-120
.

Cap
With seal, must always be fitted.

Service connection
Low-pressure side
For measuring and draining with service station.

Note:
The service connections may be removed only if the refrigerant circuit is empty - the connection is not supplied with a valve.
Note:

Depending upon the engine and the vehicle version, it may be necessary to remove the dome strut in order to be able to attach the service coupling to the service connection.

Damping chamber
Installed in the refrigerant line from the expansion valve to the compressor.
Pressure shocks that could arise on the low-pressure end when the compressor is running are reduced in the damping chamber.