Assembly overview – heater unit

Note There are different designs and makes of heater. The individual components of the various heaters are similar but not identical. The combined fitting of different makes of component is therefore not permissible → Electronic Parts Catalogue. The following illustrations show a “Valeo” heater unit. For information on distinguishing features with respect to other makes refer to → Chapter. The figures show a left-hand drive vehicle. The procedure is analogous.

Heater, flap control

1 -	Actuating lever

For actuation of defroster and air distributor flap

2 -	Air distribution flap control motor -V428-

With potentiometer for air distribution flap control motor -G645-.

Checking: Use vehicle diagnostic tester in “Guided fault finding” mode and → Current flow diagrams, Electrical fault finding and Fitting locations

Removing and installing → Chapter

3 -

Bolt

Qty. 2.

1 N·m

4 -

Bolt

Qty. 3.

1 N·m

5 -

Bolt

Qty. 2.

1 N·m

6 -	Temperature flap control motor -V68-

With potentiometer for temperature flap control motor -G92-.

Checking: Use vehicle diagnostic tester in “Guided fault finding” mode and → Current flow diagrams, Electrical fault finding and Fitting locations

Removing and installing → Chapter

7 -	Actuating lever

For actuation of heated air flap.

8 -	Heater unit

Different versions → Chapter.

The combined fitting of different makes of component is not permissible.

The following illustrations show the heater unit from “Valeo”.

The design is largely identical to that of the heater and air conditioning unit. Following components are not fitted: expansion valve, condensation drain, evaporator etc. Instead of the evaporator a flow rate limiter is fitted (only on vehicles without air conditioning system). There is no opening for the expansion valve in the plenum chamber back wall seal or this is closed off by a foam pad

Removing and installing → Chapter

9 -	Defroster and air distribution flap actuation unit

Removing and installing → Chapter

Heater, heat exchanger, auxiliary air heater element

1 -

Bolt

2 N·m

2 -	Coolant pipe with heat exchanger

Different versions. Refer to → Electronic Parts Catalogue.

Coolant supply from the engine

Removing and installing → Chapter

3 -

Clip

4 -	Coolant pipe with heat exchanger

Different versions. Refer to → Electronic Parts Catalogue.

Coolant return to the engine

Removing and installing → Chapter

5 -	Sealing ring

Different versions. Refer to → Electronic Parts Catalogue.

Renew.

6 -

Cover

For heat exchanger.

7 -

Bolt

1 N·m

8 -	Foam spacer

For sealing and insulation.

No opening for expansion valve on vehicles with no air conditioning system → Electronic Parts Catalogue.

Note fitting position.

9 -

Bracket

For coolant pipes.

10 -

Foam

For insulation

Note fitting position.

11 -	Heater unit

On vehicles without auxiliary air heater element -Z35- with auxiliary air heater control unit -J604- the opening for the auxiliary heater is closed.

Removing and installing → Chapter

12 -	Heat exchanger

Different versions. Refer to → Electronic Parts Catalogue.

Removing and installing → Chapter

13 -	Auxiliary air heater element -Z35- with auxiliary air heater control unit -J604-

Checking → Chapter

Removing and installing → Chapter

14 -

Bolt

Qty. 2.

2 N·m

15 -	Electrical wiring

For auxiliary air heater element -Z35- with auxiliary air heater control unit -J604-.

16 -	Earth cable for auxiliary air heater element -Z35- with auxiliary air heater control unit -J604-.

For auxiliary heater.

Nut 9 ± 1 N·m

17 -

Bolt

Qty. 3.

2 N·m

18 -	Clamping piece

19 -	Sealing ring

Different versions. Refer to → Electronic Parts Catalogue.

Renew.

Air intake housing, dust and pollen filter, fresh air blower, flap control

1 -	Plastic bolt or plug depending on version

Qty. 2.

0,3 N·m

2 -	Baffle plate

Removing and installing → Chapter

3 -	Housing for fresh air blower and dust and pollen filter

4 -

Bolt

Qty. 2.

1 N·m

5 -	Air intake duct

Do not dismantle.

With fresh air and air recirculation flap

Different versions. Refer to → Electronic Parts Catalogue.

Removing and installing → Chapter

6 -	Not fitted

Only on vehicles with Climatronic.

7 -	Not fitted

Only on vehicles with Climatronic.

8 -	Air recirculation flap control motor -V113-

Without potentiometer with limit switches at end stops → Current flow diagrams, Electrical fault finding and Fitting locations. Checking: Use vehicle diagnostic tester in “Guided fault finding” mode and → Current flow diagrams, Electrical fault finding and Fitting locations

Removing and installing → Chapter.

9 -

Bolt

Qty. 2.

1 N·m

10 -	Dust and pollen filter

Different versions. Refer to → Electronic Parts Catalogue.

Change interval: → Maintenance tables.

Removing and installing → Chapter.

11 -

Cover

For dust and pollen filter.

12 -	Fresh air blower -V2-

Checking: Use vehicle diagnostic tester in “Guided fault finding” mode and → Current flow diagrams, Electrical fault finding and Fitting locations

Removing and installing → Chapter

13 -	Fresh air blower control unit -J126-

Checking: Use vehicle diagnostic tester in “Guided fault finding” mode and → Current flow diagrams, Electrical fault finding and Fitting locations

Removing and installing → Chapter.

14 -

Bolt

Qty. 2.

1 N·m

Removing and installing fresh air blower -V2-

Removal and installation are identical with procedure for vehicles with air conditioning system → Chapter.

Removing and installing fresh air blower control unit -J126- Removal and installation are identical with procedure for vehicles with air conditioning system → Chapter.

Removing and installing dust and pollen filter Removal and installation are identical with procedure for vehicles with air conditioning system → Chapter.

Removing and installing heater unit It is not necessary to extract the refrigerant and to remove the expansion valve. Further removal and installation are identical with procedure for vehicles with air conditioning system → Chapter.