boot AUDI A4 1999 B5 / 1.G Heating And Ventilation System Servicing Workshop Manual

87-160

- Release pressure in coolant system by opening
cap at coolant expansion tank.

WARNING!

With hot engine, cooling system is under
pressure.
Coolant expansion tank cap must be
removed slowly.

CAUTION! - Clamp coolant hoses -A- and -B- with VAG3094 (or equivalent) and
remove from heater core inlet/outlet.
- Place catch basin below heater core connection -A- and carefully blow
coolant out of heater core with compressed air through connection -B-.
- Remove A/C system vacuum supply hose from engine and attach at
heater core inlet/outlet.
- Remove boot -C-.
Dispose of used coolant properly. Check local regulations.Do not re-use used coolant.
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87-161


CAUTION!
Immediately plug open connections on A/C components and lines to
prevent dirt and moisture contamination. - Remove bolt -A-: tightening torque 15 Nm (11 ft lb).
- Loosen refrigerant line clamp and remove lines from evaporator.
- Secure refrigerant lines in engine compartment to allow unobstructed
evaporator re-installation.
- Use blank plug from a replacement evaporator -C- to seal the
connections at the evaporator; this also aids with evaporator re-
installation.

- Remove boot -D-.
- Disconnect low pressure switch -F73- electrical connection and secure
connector end to evaporator fixture.
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87-164

Notes:

When re-installing instrument panel and
heater/air conditioner assembly, ensure the A/C
system vacuum supply hose with heater core
fixture, and low pressure switch electrical
connector and evaporator fixture are inserted
together through the plenum chamber
openings.
Ensure evaporator drain is correctly positioned
page 87
-169
.

Connect coolant hoses correctly:
Ensure boot -C- is correctly installed.Hose -A-: return flow to water pump (with vent hole).Hose -B-: supply from cylinder head.

Replace refrigerant line O-rings -A- and -B-.Evaporator refrigerant line fixture bolt tightening torque: 15 Nm (11 ft
lb). Ensure boot -D- and wiring to low pressure switch are correctly
located and secured when installing.
Pa
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g and ventilation s
ystem, servicin
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11/21/2002 htt
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pair&id=AUDI.B5.HA01.87.22

87-166


CAUTION!
A/C refrigerant system must be discharged before removing
heater/air conditioner assembly. - Clamp coolant hoses -A- and -B- with VAG3094 (or equivalent) and
remove from heater core inlet/outlet.
- Place catch basin below heater core connection -A- and carefully blow
coolant out of heater core with compressed air through connection -B-.
- Remove boot -C-.
- Discharge refrigerant system page 87
-201
.

CAUTION!
Immediately plug open connections on A/C components and lines to
prevent dirt and moisture contamination. - Remove bolt -A-.
- Remove refrigerant lines from evaporator and secure with tie wraps to
prevent interference during installation.
Pa
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g and ventilation s
ystem, servicin
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11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
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