Remove/install heater unit

AR83.70-P-5302NC

Remove/install heater unit

23.07.2019

Model

170.444/449 1# with transmission 722.6

Retrofitted stationary heater Thermo Top C

3

Coolant outlet hose, heater

11

Bracket

15

Heater-unit bracket

4

Coolant feed hose, heater

12

Combustion air intake hose

A6

Stationary heater unit

7

Fuel line

12a

Water separator

A6m1

Coolant recirculation pump

9

Coupling, power supply

14

Exhaust line

D

Spacer sleeve

10

Coupling, control lines

 

Remove/install

Notes on repairing the stationary heater

AH83.70-P-0001-03D

 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

1

Release pressure in coolant circuit

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

2

Remove front engine compartment paneling

AR61.20-P-1105A

 Unscrew exhaust duct on right side of engine compartment lining.

3

Remove fender liner in right front fender

AR88.10-P-1300G

4

Clamp off coolant feed and coolant outlet hose (4, 3)

 Clamp

*000589543700

5

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

6

Disconnect coolant hoses (3, 4) from heater (A6) and coolant circulation pump (A6m1)

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

7

Disconnect fuel line (7) from heater (A6)

 Collect escaping fuel.

8

Remove sheet-metal-screw-and-washer assembly (see arrows) from holder (15)

 Support heater (A6).

9

Unscrew two sheet-metal-screw-and-washer assemblies from holder (11) and detach spacers (D)

 Installation: Position spacer (D) between holder (11) and body.

 Support heater (A6).

10

Guide heater (A6) out in downward direction and, when doing so, detach couplings (9, 10) of electrical connection lines

 

Disassemble/assemble

11

Remove holder (11) with 3 screws (EJOT PT) and holder (15) with one screw (EJOT PT) from heater (A6)

 Installation: Pre-screw existing bore on heater (A6) with screw (EJOT PT) before mounting holders (11, 15).

 Model 170.444/449 1# with transmission 722.6
Retrofitted stationary heater Thermo Top CBolt, bracket to heater

*BA83.70-P-1009-01A

12

Disconnect coolant circulation pump (A6m1) from heater (A6)

AR83.70-P-5700FAA

13

Disconnect combustion air intake hose (12) from heater (A6)

14

Unscrew perforated plate from heater (A6) and remove water separator (12a)

15

Install in the reverse order

16

Bleed coolant circuit after installation of heater

AR83.70-P-5302-01E

Check

17

Check fuse assignment

Fuse assignment of fuse and relay box on right side of engine compartment



GF54.15-P-1256-02AA

 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

18

Commission stationary heater



Start up stationary heater

AZ83.70-P-0008-04A

 If the heater (A6) switches off automatically before reaching its operating temperature and cannot be restarted,

a fault interlock exists:



Override malfunction interlock

AR83.70-P-5302-07CA

19

Check cooling system for leaktightness

AR20.00-P-1010HA

 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