Bosch SSB85 - Cleaning the Heat Exchanger

6720866940 (2017/11) US SSB
26 | Maintenance schedule & procedures
[6] Remove the gasket;
Gasket
Fig. 69 Gasket
[7] Pull out the burner head. Rotate the burner head to align the mark
(A) to the igniter (B);
A B
Fig. 70 Burner head
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WARNING: After cleaning the burner head reassemble with
a new gasket. Replace the gas valve gasket.
8.5 Cleaning the Heat Exchanger
It is necessary to clean the interior surface of the heat exchanger.
Carefully perform all steps below:
[1] To access the combustion chamber repeat the burner head removal
process then proceed to step 2;
[2] Unscrew bolt (A) partially, open the clamp (B) fastening the top cap
to the heat exchanger body;
A B
Fig. 71 Clamp fastening
[3] Remove the exchanger top cap (including the insulation);
Top cap + insulation
Fig. 72 Exchange top cap
[4] The opening provides access to the combustion chamber;
Top cap + insulationBottom insulation disk
Fig. 73 Combustion chamber
[5] To clean the combustion chamber utilize the cleaning kit;