1998 AUDI A4 Heating And Ventilation System Servicing Workshop Manual

87-165

Heater/air conditioner assembly,
removing and installing (1997 )


CAUTION!

Obtain security code for anti-theft radio.
Note customer's pre-set radio stations.
Move power seats to most rearward
position.
Switch off ignition and disconnect battery
ground (GND) strap.

- 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.
Dispose of used coolant properly. Check
local regulations.
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Do not re-use used coolant.
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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.
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87-167


Remove glovebox Repair Manual, Body Interior, Repair Group 70

Remove driver side under-dash panel, center console and instrument
panel outer skin Repair Manual, Body Interior, Repair Group 70
- Plug evaporator openings using cap supplied with replacement
evaporator -C-.
- Remove bulkhead grommet -D-.

- Remove instrument panel support -A-.
- Loosen instrument panel support -B- (the upper mounting bolt to the
heater/air conditioning assembly can not be removed).
- Remove floor outlet page 87
-134
.
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87-168


- Remove bolts -A-.
- Disconnect all electrical connections from instrument panel harness to
heater/air conditioner assembly.

Notes on installation: - Remove bolts -A-.
- Remove heater/air conditioner assembly towards passenger side.
- Install in reverse order of removal.
Replace all damaged heater/air conditioner assembly seals.Replace all removed cable tie wraps in the same location.Always replace evaporator inlet/outlet O-rings.Ensure refrigerant lines fit into evaporator without binding.Check evaporator line and heater core bulkhead grommets for correct
fit. Check evaporator drain and evaporator drain valve for correct fit (1996
page 87
-169
; 1997 page 87
-171
).
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87-169

Evaporator housing drain, checking
(1996)


Notes: - Evaporator drain valve flap -A- must not stick, must close completely
and drain opening must be pointing downwards.
Remove drain valve downwards out of the floor panel.When installed, the drain valve must not be touching the heat shield.The drain valve must not stick as a result of wax or underbody
sealant. If complaints of moisture in passenger compartment exist, check
evaporator drain and drain valve and clean if necessary.
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87-170


Notes: - Foam seal -B- must fit tightly against drain funnel -C-.
- Plate -A- must be fitted at drain in order to support foam seal.
The drain funnel and foam seal can only be replaced with A/C housing
with evaporator assembly removed (removing and installing heater/air
conditioner assembly page 87
-172
).
The stopper -D- on drain prevents liquid flowing back into the foam
seal.

Drain funnel -C- must be secured to floor panel and must not impede
operation of drain valve -E-.
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87-171

Evaporator housing drain, checking
(1997 )


Notes:

Drip guide -A- on the evaporator housing drain prevents liquid from
flowing back into the foam seal -B-.

Should drip guide break off, install stopper -D- and seal with silicone
adhesive to the drain tube.
Pa
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11/21/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.HA01.87.22