Volkswagen Golf / Golf GTI / Jetta. Manual — part 1005

refrigerant circuit and servicing (retrofit)

Note:

- For environmental reasons and on account of the
corresponding legislation, refrigerant R12 can no longer be
manufactured or supplied. Refrigerant R134a has been
developed as a replacement for R12.

- Air conditioning systems developed and designed for
refrigerant R12 cannot however simply be charged with
refrigerant R134a. To ensure trouble-free operation of the
air conditioning system even after conversion, various
components of the refrigerant circuit must be replaced.

- A precise description of the conversion procedure and
information on the servicing of converted refrigerant circuits
can be found in

Repair Manual: Air conditioner with

refrigerant R12 Parts 2 and 3 .

Keeping refrigerant records

The environmental statistics law requires records to be kept
on the use of refrigerants.

Consequently, motor vehicle workshops may well have to
provide the relevant local authorities with information on
their use of refrigerant. It is therefore advisable to keep
records

HSO Environment Vol. 2-2. 43

Laws and regulations

13/2/2005

00 - 4

Refrigerant circuit

Important repair notes on air conditioning
systems

- Air conditioning systems designed for refrigerant R12 are
never to be filled with refrigerant R134a without a retrofit

00-3, R12 refrigerant circuit, converting to R134a
refrigerant circuit and servicing (retrofit)

.

- The refrigerant oils specifically developed for R134a and
R12 refrigerant circuits are never to be mixed.

- Service stations which come in contact with the refrigerant
are only to be used for the intended refrigerant.

- Components of R134a refrigerant circuits can be
recognized from their labelling, green stickers or design
(e.g. different threads) to prevent interchange with
components for refrigerant R12.

- A label indicating the refrigerant used is provided in the
engine compartment on the lock carrier or in the plenum
chamber.

- Different refrigerants are never to be mixed.

Note:

- When working on the refrigerant circuit, always follow the
information given in the Sections on "Safety measures"

00-1, Safety measures for working on vehicles with air
conditioning system and for handling refrigerant R134a

and

"Basic rules for working on refrigerant circuit"

00-1,

Basic rules for working on refrigerant circuit

.

Refrigerant circuits, converting from R12
refrigerant to R134a refrigerant

CFC refrigerants are no longer used in the automotive
industry.

Converting refrigerant circuits from R12 refrigerant to
R134a refrigerant and servicing converted circuits.

Repair Manual Air conditioner with refrigerant R12 Parts

2 and 3

Working with the service station

Important notes for working with the service

Refrigerant circuit

13/2/2005

station

Observe the following with regard to service station
operation (e.g. A/C service station VAS 6007A ):

- The filters and dryers installed must be replaced at the
latest on completion of the service life specified in the
relevant operating instructions.

- Exclusive use is to be made of refrigerant oils which have
been approved for the vehicle-specific refrigerant circuit.

Parts Catalog

In the following situations, extracted refrigerant is not to be
re-used even after treatment in the service station:

- In the event of compressor damage causing
decomposition of the refrigerant due to overheating.

- If dark, sticky deposits are present in the refrigerant circuit
(this can only be determined after opening system).

- If there is any doubt about the composition of the
refrigerant extracted from the refrigerant circuit.

The service station is to be drained in all these cases

00-4, Refrigerant circuit, discharging using service station

,

the system cleaned if necessary and the filters, dryers and
refrigerant oil replaced.

Contaminated refrigerant can, e.g. in the Federal Republic
of Germany, be returned to the supplier in so-called
recycling containers for recycling or for environmentally
safe disposal (other or additional regulations may apply in
other countries).

Commercially available service stations can be classified in
2 groups:

- A. Service stations which clean extracted refrigerant for
re-use (so-called extraction and recycling stations), e.g.

Refrigerant circuit

13/2/2005

A/C service station VAS 6007A .

- B. Service stations which transfer extracted refrigerant to
recycling containers (for large-scale recycling). These are
referred to as extraction systems.

Service station, connecting for
measurement and testing

- Work procedure may vary depending on the type of tools
selected (the tool-specific operating instructions should
therefore be followed).

Note:

- The work procedure is always to be performed as
described in the operating instructions for the r A/C service
station VAS 6007A .

The charging hoses are to be connected as follows to
prevent the ingress of air or moisture into the refrigerant
circuit:

- Switch ignition off.

- Connect service station to power supply.

- Unscrew caps from service connections or connections
with valve (refer to vehicle-specific refrigerant circuit).

Repair Manual, Heating & Air Conditioning, Repair

Group 87 ,

- Evacuate charging hoses if necessary.

Note:

- Connect quick-release couplings to service connections of
refrigerant circuit.

Warning!

A/C compressor or service station may be damaged if
quick-release couplings are opened.

A "short circuit" may occur between high and low-
pressure sides of refrigerant circuit if engine is running
and quick-release couplings have been opened.

Engine must not be running or quick-release couplings
at service connections must be closed.

Refrigerant circuit

13/2/2005