Volkswagen Amarok 2011 Workshop Manual page 75

Amarok 2011 ➤ , Beetle 2012 ➤ , Bora 1999 ➤ , CC 2010 ➤ , CC 2012 ➤ , ...
Caution
♦ If there is evidence to suggest that chemical substances
have been added in the vehicle to seal leaks, do not con‐
nect the air conditioner service station and do not extract
the refrigerant.
♦ Chemical substances used to seal leaks form deposits in
the refrigerant circuit. These can impair the function of the
air conditioning system and cause the air conditioning
system (and your air conditioner service station) to fail.
♦ Make your customer aware of the fact that there are sub‐
stances in his/her air conditioning system that do not have
VW approval and therefore the refrigerant circuit cannot
be purged. The refrigerant circuit can only be repaired by
replacing all components that have come into contact with
this substance.
Note
Volkswagen rejects the use of chemical substances for pur‐
♦
poses of sealing leaks in refrigerant circuits.
Chemical substances used for sealing leaks in refrigerant cir‐
♦
cuits often react with the surrounding air and the humidity
contained within. They cause deposits to build up in the re‐
frigerant circuit (and your air conditioner service station),
valves to malfunction and defects in other components with
which they come into contact. These deposits cannot be com‐
pletely removed from the components (not even by purging).
The refrigerant circuit can only be repaired by replacing all
components that have come into contact with this substance.
It is often not possible to detect from the outside whether
♦
chemical substances have been used to seal leaks in the re‐
frigerant circuit. The adhesive label that serves to identify its
use can usually not be found. Therefore, exercise caution on
vehicles for which you have no service or repair record.
• To work as cleanly as possible and avoid the task becoming
labour intensive when removing contaminants (e.g. friction
dust and particles from defective air conditioner compressor)
and old refrigerant oil, the refrigerant circuit must be purged
using refrigerant R134a.
On vehicles with electrical air conditioner compressor, observe
the notes on renewing the electrical air conditioner compressor -
V470-. If the electronics of the air conditioner compressor are
damaged, the refrigerant circuit must not always be cleaned
⇒ page 161 .
The refrigerant circuit must be purged with refrigerant R134a if:
♦ Dirt or other contaminants are in the refrigerant circuit.
♦ If during evacuation of a leak-tight refrigerant circuit the vac‐
uum display is not constant on gauge (moisture in the refrig‐
erant circuit, which generates vapour pressure).
♦ If the refrigerant circuit has been left open for longer than nor‐
mally required for repairs (e.g. following an accident).
♦ Pressure and temperature measurements in the refrigerant
circuit indicate that there is moisture in the refrigerant circuit.
♦ There is doubt about the amount of refrigerant oil in the refrig‐
erant circuit. If the air conditioner compressor is to be reinstal‐
led, drain refrigerant oil out of air conditioner compressor via
Air conditioning system with refrigerant R134a - Edition 10.2014
7. Clearing refrigerant circuit of contaminants
69