Volkswagen Golf / Golf GTI / Jetta. Manual — part 965

87-77

Airborne properties

Escaped refrigerant gases are heavier than

air and will gather first in low places, like
under the car. R-134a refrigerant gas
displaces oxygen and may cause
suffocation in low areas of poor air
circulation.

Refrigerant R-134a is not poisonous in any

state (liquid or gas) and is safe when used
properly.

Affects on plastic

Refrigerant R-134a will deteriorate some

plastics. Therefore, when making system
repairs, use only genuine VW replacement
parts which are specified for use with R-
134a refrigerant.

Affects on metal

In its pure state, refrigerant R-134a is

chemically stable and will not attack iron,
copper, brass or aluminum. However, the
mixture of R-134a and PAG oil may
deteriorate certain metals (copper).
Therefore, when making system repairs,
use only genuine VW replacement parts
which are specified for use with R-134a
refrigerant.

Water solubility

Liquid R-134a refrigerant will absorb only

very minute quantities of moisture.
However, R-134a vapor can absorb large
amounts of moisture.

A/C refrigerant system

13/2/2005

87-78

Flammability

R-134a refrigerant is not flammable.

Refrigerant containers

DO NOTexceed maximum rated capacity of

refrigerant container.

Leak detection

Use halogen leak detector Hitec HI400A-

TELor equivalent to check for R-134a
system leaks. This tool can also be used to
detect leaks in R-12 systems. Many
currently available R-12 leak detectors
cannot detect R-134a refrigerant leaks.

R-134a refrigerant oil

A special Polyalkylene Glycol (PAG)

synthetic oil is used in R-134a systems. This
oil is NOT compatible with mineral based
oils used in R-12 systems.

A/C refrigerant system

13/2/2005

87-79

A/C refrigerant system,
identification

Note:

Before carrying out any work on the
A/C refrigerant system, refer to A/C
system safety measures

Page 87-

69

.

A/C refrigerant system is charged
with refrigerant R-134a.

A label specifying refrigerant type
may be located on the compressor
or radiator support.

A/C refrigerant circuit with

expansion valve and receiver
drier

Note:

Arrows indicate direction of
refrigerant flow.

1 - Evaporator

2 - Expansion valve

3 - High pressure service valve

4 - Sight glass (if equipped)

5 - Receiver drier

6 - Condenser

7 - Compressor

A/C refrigerant system

13/2/2005

87-80

A/C refrigerant system,
component overview

Compressor

The compressor is driven via a belt
on the engine when the A/C clutch
engages (A/C "ON").

Low-pressure refrigerant gas from
the evaporator is compressed by the
compressor. After compression, the
refrigerant gas (now high-pressure)
flows to the condenser.

Notes:

The compressor contains

refrigerant oil that is mixable
under all temperatures with the
refrigerant.

A label on the compressor

indicates that compressor is for
R-134a systems only.

Condenser

The condenser transfers heat from
the compressed refrigerant gas to
the outside air which causes the
refrigerant to change state from a
gas to a liquid.

Note:

The condenser for the R-134a
refrigerant system may be identified
with a green label.

A/C refrigerant system

13/2/2005