Remove/install heater unit

AR83.70-P-5302F

Remove/install heater unit

07.03.2019

Model

202.### 1# with engine 611.960

with heater booster or Thermo Top C stationary preheating

Illustration shows installation/removal of heater booster

3

Coolant outlet line, heater

9

Coupling, power supply

14

Exhaust line

4

Coolant feed line, heater

10

Coupling, control lines

15

Exhaust line holder

6

Nut, heater mount

11

Heater holder

A6

Heater booster unit

7

Fuel feed line

12

Combustion air intake line

A6m1

Coolant circulation pump (only with code KLA 581)

8

Coupling, coolant circulation pump (only with code KLA 581)

 

Remove/install

 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

Distinguishing features stationary heater/stationary preheater/heater booster

AH83.70-P-0003-01B

1

Remove front section from noise encapsulation

AR94.30-P-5300A

 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

2

Release pressure in coolant circuit

 To do so, turn cap of coolant expansion reservoir to detent position 1.

3

Clamp off coolant feed line and coolant outlet line (4 and 3) at pipes and disconnect

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

 Clamp

*000589543700

4

Clamp off fuel feed line (7) and disconnect heater (A6)

 Clamp

*000589403700

5

Unscrew nuts (6) of heater mount at longitudinal frame member

 Before unscrewing nuts (6), support heater from below.

6

Unscrew nut (6) of heater mount underneath right lamp unit

 Before unscrewing nuts (6), support heater from below.

7

Guide out heater (A6) with holders (11 and 15) in downward direction and, when doing so, disconnect couplings (9 and 10) of electrical connection lines

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

 

Disassemble/assemble

8

Disconnect coupling (8) to coolant circulation pump (A6m1)

 On vehicles with stationary preheating and automatic air conditioning (code 581).

9

Disconnect coolant feed line and coolant outlet line (4 and 3) and combustion air intake line (12) from heater (A6)

10

Disconnect exhaust gas line (14) from heater (A6)

11

Remove holders (11 and 15) from heater (A6)

 On vehicles with stationary preheating, an exhaust muffler is mounted on the holder.

 Model 202Bolt, bracket to heater

*BA83.70-P-1009-01A

12

Disconnect coolant circulation pump (A6m1) with coolant feed hose from heater (A6)

 On vehicles with stationary preheating and automatic air conditioning (code 581).

13

Install in the reverse order

Check

14

Check relay assignment of heater (A6) on left in engine compartment



GF54.15-P-1257-03C

15

Check fuse assignment of heater (A6) on left in engine compartment



GF54.15-P-1256-03B

16

Bleed coolant circuit after installation of heater

AR83.70-P-5302-01D

17

Check cooling system for leaktightness

AR20.00-P-1010HA

18

Perform heater booster (HB) diagnostic function check



AD83.70-P-3004A

19

Perform commissioning of stationary preheating



AZ83.70-P-5302-08B

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

(continue with)



Override malfunction interlock

AR83.70-P-5302-07B

 Stationary heater

Number

Designation

MODEL 170, 202, 208, 210 with Thermo Top C heater

BA83.70-P-1009-01A

Bolt, bracket to heater

Nm

10