low oil pressure AUDI A4 2000 B5 / 1.G Refrigerant System Components Workshop Manual

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Refrigerant system (R-134a),
components

A/C compressor


The compressor is driven via a belt on the engine when the A/C clutch
engages (A/C ON).
Low pressure refrigerant gas from the evaporator is compressed by the
compressor. After compression, the refrigerant gas (now high pressure)
flows to the condenser.
The variable displacement A/C compressor varies piston stroke and
output depending on load requirements and suction pressure.
Notes:
Zexel A/C compressors were installed from start of production. During
m.y. 1996, Nippondenso (Denso) type compressors are installed as a
running change. These compressors are not equipped with A/C speed
sensor G111. The compressor contains PAG type refrigerant oil that is mixable
under all temperatures with refrigerant R-134a. A label on the compressor indicates that compressor is for R-134a
systems only.
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Valve connections for pressure
switches


A Schrader valve is installed under A/C system pressure switches to allow
replacement without discharging the refrigerant system.
Note:
A/C system switches are available in different versions. Always refer to
the latest parts information to ensure correct switch application. - A/C system low and high pressure switches use different size threads.
- Use only the correct switches and O-ring seals specified for use with R-
134a refrigerant and PAG oil.
A - Switch connection (soldered)
B - O-ring seal
C - Schrader valve insert
Pa
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gerant s
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(R-134a
), com
ponents
11/21/2002 htt
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play?action=Goto&t
yp
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pair&id=AUDI.B5.HA01.87.6