Refrigerant Circuit, Flushing - Audi 100 1991 Repair Manual

Audi 100 1991 ➤ , Audi 80 1992 ➤ , Audi A1 2011 ➤ , Audi A2 2001 ➤ , A ...
Refrigerant R134a Servicing - Edition 01.2011
– Moisture or dirt has gotten into the refrigerant circuit, for ex‐
ample, after a crash.
– Refrigerant oil is dark and viscous.
– There is too much refrigerant oil in the refrigerant circuit after
replacing the compressor.
– The A/C compressor had to be replaced due to internal dam‐
age (for example, noises or no output).
Note
When flushing components with compressed air and nitrogen, al‐
ways extract the gas mixture escaping from the components with
suitable extraction units (workshop extraction system).
1.4.11

Refrigerant Circuit, Flushing

Note
In the case of vehicles on which the refrigerant pipes have no
♦
threads for connection of Adapter set -1785- , use, for exam‐
ple, a flushing gun with rubber end piece or an adapter from
Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
the Adapter case for VW/Audi passenger cars -VAS 6338/1-
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
for blowing through the individual components. When using a
with respect to the correctness of information in this document. Copyright by AUDI AG.
flushing gun with rubber end piece, take special care not to
damage the connections (crushing or scratching).
Evaporator is to be flushed via the connection for low-pressure
♦
pipe (large diameter) after removing expansion valve or re‐
moving restrictor.
Always flush components in direction opposite to refrigerant
♦
flow.
Check expansion valve and replace if dirty or corroded.
♦
Replace any components on which dark, sticky deposits can‐
♦
not be removed with compressed air. Flush these components
using refrigerant R134a or replace.
Thin, light grey deposits on the insides of pipes do not impair
♦
the function of the components.
After flushing, always replace receiver or reservoir and re‐
♦
strictor. Replace dryer cartridge on condensers with dryer.
If the reservoir / dryer cartridge is integrated in the condenser,
♦
then they cannot be replaced individually and the condenser
must be replaced. Refer to the Electronic Parts Catalog (ET‐
KA) and ⇒ Heating, Ventilation and Air Conditioning; Rep. Gr.
87 ; Removal and Installation .
Reservoirs, where it is possible to replace the dryer cartridge,
♦
have an additional filter, which must also be replaced with the
dryer cartridge.
After Blowing Through The Refrigerant Circuit
– Replace these components depending on equipment (restric‐
tor and reservoir, expansion valve and fluid reservoir or dryer
cartridge). Refer to ⇒ Heating, Ventilation and Air Condition‐
ing; Rep. Gr. 87 ; Removal and Installation (vehicle-specific
repair manual) and Electronic Parts Catalog (ETKA).
– Replace the A/C compressor, depending on its condition. Re‐
fer to ⇒ Heating, Ventilation and Air Conditioning; Rep. Gr.
87 ; Removal and Installation (vehicle-specific repair manual)
and Electronic Parts Catalog (ETKA) or drain the rest of the
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Rep. Gr.00 - General, Technical Data