Leak Detection - Audi 100 1991 Repair Manual

Audi 100 1991 ➤ , Audi 80 1992 ➤ , Audi A1 2011 ➤ , Audi A2 2001 ➤ , A ...
Note
The relationship between pressure and temperature indicated on
the gauges no longer applies if no liquid is present and the pres‐
sure is built up solely by gas.
4.2

Leak Detection

⇒ "4.2.1 Refrigerant Circuit, Determining Leaks ", page 143
⇒ "4.2.2 Refrigerant Circuit, Tracing Leaks Using Electronic Leak
Detector V.A.G 1796", page 144
⇒ "4.2.3 Refrigerant Circuit, Tracing Leaks Using Leak Detection
System VAS 6201", page 144
4.2.1 Refrigerant Circuit, Determining Leaks
Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
Note
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
Minor leaks can be detected using an electronic leak detector
♦
or UV leak detector lamp.
This repair manual describes two different methods for de‐
♦
tecting leaks in the refrigerant circuit. These methods have
been tested and result in success when used correctly.
Many methods for detecting leaks in the refrigerant circuit are
♦
offered in the open market. These methods do not always
have optimum results and if they are not performed exactly to
the specification and may result that several components in
the refrigerant circuit have leaks. Also, refrigerant circuit com‐
ponents can be damaged by some methods.
♦ Do not repair components with leaks; always replace them.
♦ Do not charge a leaking refrigerant circuit with refrigerant.
Evacuate the circuit and check it for leaks before charging.
Refer to ⇒ "2.4.11 Evacuating Refrigerant Circuit", page 89
Caution
♦ Audi does not approve the use of chemicals to seal leaks
in the refrigerant circuit (leak stop additives).
♦ Chemicals that seal leaks in the coolant circuit form de‐
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.
Note
Chemical materials to seal leaks in the refrigerant circuit react with
air or the moisture in the air and form deposits in the refrigerant
circuit and the A/C service station that lead to malfunctions in the
valves and other components that come into contact with such
chemicals. These deposits cannot be removed 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.
♦ Refrigerant circuit, tracing leaks using electronic leak detector
V.A.G 1796. Refer to
Refrigerant R134a Servicing - Edition 01.2011
.
143
4. Diagnosis and Testing