Remove/install heater unit

AR83.70-P-5302HA

Remove/install heater unit

20.01.2020

Model

240

with code 228 (Additional warm water heating)

1

Nuts

8

Coolant feed hose

2

Bracket

9

Coolant return flow hose

3

Nuts

10

Coolant pump

4

Screw

11

Fuel feed line

5

Screw

12

Electrical connectors

6

Exhaust nozzle

A2/45

Right front TPM [RDK] wheel antenna

7

Circuit

10

Coolant pump

13

Clutch

14

Intake muffler

15

Fuel hose

16

Bolts

17

Bolts

18

Bracket

19

Bolts

20

Combustion air intake hose

21

Coolant hose

22

Bracket

23

Bracket

A6

STH heater unit

 

Remove/install

 Danger

Risk of fire/risk of explosion due to short circuit and escaping oxyhydrogen gas. Risk of (burn) injury caused by caustic burns to eyes, skin and mucous membranes from battery electrolyte/mist, short circuit and arcing. Risk of poisoning caused by swallowing battery electrolyte or absorption of lead through the skin or body orifices. Risk of death due to voltage U >= 30 V AC and U >= 60 V DC.

No fires, sparks, open flames, or smoking. Wear acid-resistant gloves, clothing, and glasses. Pour battery acid only into suitable and appropriately marked containers.

AS54.10-Z-0001-01A

1

Disconnect battery ground line

AR54.10-P-0003H

Topical note

Notes on battery

AH54.10-P-0001-01A

2

Remove finder liner in front fender

AR88.10-P-1300H

3

Unscrew nuts (1) and remove right front TPM wheel antenna (A2/45) with holder (2) from crossmember

 Place right front TPM wheel antenna (A2/45) to one side.

 Warning

Risk of injury to skin and eyes suffering scalding from contact with hot coolantspray. Risk of poisoning from swallowing coolant.

Do not open cooling system unless coolant temperature is below 90 °C. Open cap slowly and release the pressure. Do not pour coolant into beverage containers.
Wear protective gloves, protective clothing and safety glasses.

AS20.00-Z-0001-01A

4

Release pressure in coolant circuit

 To do so, open cap of coolant expansion reservoir.

5

Pinch off coolant feed hose (8) and coolant return line hoses (9) with Matra clamps (7)

 Clamp

*000589403700

6

Disconnect coolant feed hose (8) from stationary heater (A6)

 Collect escaping coolant in a clean vessel and, after installation of heater, pour back into coolant expansion reservoir.

7

Disconnect coolant return hose (9) from coolant pump (10)

 Collect escaping coolant in a clean vessel and, after installation of heater, pour back into coolant expansion reservoir.

 Danger

Risk of explosion caused by fuel igniting, risk of poisoning caused by inhaling and swallowing fuel as well as risk of injury to eyes and skin caused by contactwith fuel.

No fires, sparks, open flames or smoking. Pour fuels into suitable and appropriately marked containers only.
Wear protective clothing when handling fuel.

AS47.00-Z-0001-01A

8

Disconnect fuel line (11)

 Collect escaping fuel.

9

Undo screw (5) by 5 turns

10

Remove nuts (3) and screw (4)

 Nut, heater mount on body

*BA83.70-P-1007-01C

 Bolt, heater bracket on body

*BA83.70-P-1005-01C

11

Detach exhaust nozzle from stationary heater (A6) and swivel stationary heater (A6) forward

12

Disconnect electrical connectors (12) and remove stationary heater (A6) with detachable parts

 

Disassemble/assemble

13

Remove coupling (13) from holder (22)

 Turn coupling (13) counterclockwise and remove from holder (22).

14

Disconnect coolant hose (21) from stationary heater (A6)

15

Remove screws (17) and remove coolant pump (10) with holder (23) from stationary heater (A6)

 Bolt, heater to bracket

*BA83.70-P-1004-01C

16

Remove screws (19) and remove holder (18) from stationary heater (A6)

 Bolt, bracket to heater

*BA83.70-P-1008-01C

17

Disconnect combustion air intake hose (20) from stationary heater (A6)

18

Open cable tie and remove intake muffler (14) from holder (22)

19

Remove screws (16) and remove stationary heater (A6) from holder (22)

20

Install in the reverse order

21

Bleed coolant circuit after installation of the stationary heater (A6)

AR83.70-P-5302-01M



Check

 Danger

Risk of explosion caused by fuel vapors igniting, risk of poisoning caused by inhaling combustible gases and risk of injury caused by burns during and after operation of heater unit

Do not operate stationary heater, auxiliary heater or engine with heater booster in closed rooms or when refueling. Allow heater unit to cool down after operation and wear protective gloves.

AS83.70-Z-0002-01A

22

Start up stationary heater

 See Star Diagnosis.

If the stationary heater (A6) switches off automatically before reaching its operating temperature and cannot then be restarted, a fault interlock is present:



Cancel fault interlock, see Star Diagnosis.

23

Check cooling system for leaktightness

 Stationary heater unit

Number

Designation

Model 240
with Thermo Top C heater unit

BA83.70-P-1004-01C

Bolt, heater to bracket

Nm

5

 Stationary heater unit

Number

Designation

Model 240
with Thermo Top C heater unit

BA83.70-P-1005-01C

Bolt, heater bracket on body

Nm

5

 Stationary heater unit

Number

Designation

Model 240
with Thermo Top C heater unit

BA83.70-P-1007-01C

Nut, heater mount on body

Nm

5

 Stationary heater unit

Number

Designation

Model 240
with Thermo Top C heater unit

BA83.70-P-1008-01C

Bolt, bracket to heater

Nm

8