Refrigerant Circuit Flushing With Refrigerant R134A - Audi 100 1991 Repair Manual

Audi 100 1991 ➤ , Audi 80 1992 ➤ , Audi A1 2011 ➤ , Audi A2 2001 ➤ , A ...
Refrigerant R134a Servicing - Edition 01.2011
1.4.13 Refrigerant Circuit Flushing With Refrig‐
erant R134a
Caution
♦ If it is suspected that chemicals were added to the refrig‐
erant circuit to seal leaks, chemical substances to seal
leaks in the refrigerant circuit (leak stop additive), do not
connect the A/C service station and do not extract the re‐
frigerant.
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permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
♦ Chemicals that seal leaks in the coolant circuit form de‐
with respect to the correctness of information in this document. Copyright by AUDI AG.
posits that affect the function of the A/C system and lead
to failure of the A/C system and the A/C service station.
♦ Inform that customer that there are substances in the A/C
system that are no approved by Volkswagen.
Note
Audi does not approve the use of chemicals to seal leaks in
♦
the refrigerant circuit (leak stop additives).
Chemical materials to seal leaks in the refrigerant circuit react
♦
with air or the moisture in the air and form deposits in the re‐
frigerant circuit and the A/C service station that lead to mal‐
functions in the valves and other components that come into
contact with such chemicals. These deposits cannot be re‐
moved completely from the components, even by flushing. It
is only possible to service the refrigerant circuit by replacing
all the components which come in contact with this material.
It is not possible to recognize chemical substances to seal
♦
leaks in the refrigerant circuit (leak stop additive) and the label
that is supposed to come with them is usually not there. There‐
fore be careful when working with if you do not know its service
history.
• Refrigerant circuit must be flushed with refrigerant R134a in
order to force out moisture and other contaminants as well as
old refrigerant oil as efficiently as possible, without wasting
refrigerant, without the need for extensive assembly work and
without endangering the environment.
Flush The Refrigerant Circuit
– In the event of dirt or other contamination in the circuit.
– If vacuum reading is not maintained on evacuating a leak-free
refrigerant circuit (pressure build-up due to moisture in refrig‐
erant circuit).
– If refrigerant circuit has been left open for longer than normal
(such as following an accident).
– Pressure and temperature measurements in the refrigerant
circuit indicate the likelihood of moisture.
– In the event of doubt about the amount of refrigerant oil in the
circuit.
– The A/C compressor had to be replaced on account of internal
damage (such as noise or no output).
– If stipulated by the vehicle-specific repair manual following re‐
placement of certain components.
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Rep. Gr.00 - General, Technical Data