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with respect to the correctness of information in this document. Copyright by AUDI AG.
Reason:
If refrigerant R134a is released into the environment, it enhances
the green house effect.
Note
♦
Refrigerant R134a has far less of a greenhouse effect than
R12.
♦
Because R-134a does not contain chlorine atoms, the major
catalyst in ozone depletion, refrigerant R-134a has no ozone
depletion potential. Depletion of the ozone layer in the upper
atmosphere is however only brought about by the splitting of
carbon–chlorine bonds (as is the case, for example, with re‐
frigerant R12).
After discharging the air conditioner, disconnect harness connec‐
tor from A/C Compressor Regulator Valve -N280- or from the High
Pressure Sensor -G65- .
Reason:
The A/C compressor regulator valve -N280- is no longer activated
and the A/C compressor runs at idle. The A/C compressor is de‐
signed so the lubrication of the A/C compressor components at
idle is guaranteed by an internal oil circuit (as long as there is
enough refrigerant oil in the A/C compressor).
1.18
Refrigerant Circuit, Repairs
WARNING
Before working on electrical system (wiring), remove relevant
fuse(s).
Note
Disconnect battery before starting electric welding work on vehi‐
cle. Refer to⇒ Electrical Equipment; Rep. Gr. 27 ; Removal and
Installation .
The A/C refrigerant system may be drained and opened only if it
is for safety reasons. Refer to
⇒ “1.5 A/C and Refrigerant Safety Precautions“, page 29
or if
components of the A/C refrigerant system must be replaced. Re‐
fer to
⇒ “1.17 Refrigerant Circuit, Draining“, page 36
.
When performing all other usual vehicle repair work, the refriger‐
ant circuit of the A/C system should remain closed.
Note
The connections for the senders/switches described in this Work‐
shop Manual are fitted with a valve which closes automatically
when the switches are unscrewed. These switches can thus be
replaced in any Audi and Volkswagen workshop even though the
refrigerant circuit is fully charged.
Service work on the A/C system that require the refrigerant circuit
to be discharged and thus cannot be performed in every Audi and
VW workshop are described in
⇒ “2.3 Refrigerant Circuit Components Overview“, page 49
.
Audi TT 2007 ➤
Heating, Ventilation and Air Conditioning - Edition 01.2011
1. General Information
37