Cleaning Air Conditioner Evaporator - Audi Air conditioning 2003 A8 Workshop Manual

Audi A8 2003 ➤
Air conditioning - Edition 09.2010
♦ As the activated charcoal layer permanently bonds some of
the pollutant particles, it is appropriate to replace the dust and
pollen filter sooner than prescribed under the following usage
conditions:
- Vehicle operation in areas with severe air pollution
- Vehicle operation with „Automatic air recirculation" function pre‐
dominantly deactivated
♦ On vehicles with air quality sensor -G238- , the air conditioner
should be operated as far as possible in „automatic air recir‐
culation" mode. Should it however be necessary or desirable
to deactivate the function, attention must be paid to the fol‐
lowing:
– The activated charcoal layer in the dust and pollen filter be‐
comes saturated after a certain length of time.
– A saturated filter can no longer absorb pollutants and allows
them to pass unhindered.
♦ The main function of a dust and pollen filter and air quality
sensor is to prevent peak pollution levels entering the pas‐
senger compartment. The following must however be heeded:
– If a vehicle is driven in an area with a relatively clean environ‐
ment (with few gaseous pollutants in the air), the point at which
Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
switching from fresh air to air recirculation mode takes place
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
is different to that in areas with a high basic impact level (e.g.
with respect to the correctness of information in this document. Copyright by AUDI AG.
industrial estates).
– Irrespective of the basic impact level, switching from fresh air
to air recirculation mode always takes place if there is an in‐
crease in pollutant level (e.g. on driving through a cloud of
diesel emissions from a lorry).
5.4

Cleaning air conditioner evaporator

Note
A wide variety of evaporator cleaning methods which act in
♦
different ways are available on the market. The currently ap‐
proved evaporator cleaning method authorised by Audi em‐
ploys the ultrasonic A/C cleaner -VAS 6189- . Information on
any other methods checked and approved by Audi over the
course of time will be made available in the „Audi ServiceNet"
for example.
Air conditioner odours may have different causes. Only some
♦
of these odours occur in the evaporator of the air conditioning
unit and can therefore be eliminated by cleaning the evapo‐
rator with the ultrasonic A/C cleaner -VAS 6189- for example.
5.4.1 Possible cause of odour formation
♦ Smell of burnt oil
– Generally occurs in the engine compartment due to leakage
at the engine or gearbox
♦ Sulphur-like smell of exhaust gas
– Caused by leakage at the exhaust system
– Caused by exhaust gas ingressing into the passenger com‐
partment e.g. on reversing (on driving through cloud of ex‐
haust fumes)
♦ Fishy smell of coolant
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Rep. gr.87 - Air conditioning system