Fan - Bosch ZSB18 - 2A Installation And Servicing Instructions

50 | Service and spares
B Rotate fan and air/gas manifold assembly (1.) around
the top of the heat exchanger until the lug on the air/
gas manifold is visible.
1.
Fig. 86 Rotate the air/gas manifold assembly
B Lift up assembly and remove from boiler.
NOTE: After re-assembly, check the CO/CO
levels as described in section 6.6 Setting
the air/gas ratio.
6.8.8

Fan

B Remove the air/gas manifold from the boiler as
described in the previous section.
1. Remove two screws retaining the fan to the air/gas
manifold.
2. Remove the air/gas manifold.
3. Remove the screw holding the retaining plate.
4. Remove the retaining plate.
5. Remove three screws and the mixing chamber.
Re-assemble with new fan ensuring seals are correctly
fitted.
6 720 646 195a (2010/11)
2.
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2
5.
5.
6.
5.
Fig. 87 Dismantling the air/gas manifold assembly
Flap valve assembly
There is no need to remove the mounting flange from the
fan assembly just to gain access to the flap.
B Twist the mixing chamber clockwise to release from
the mounting flange.
B Pull the mixing chamber off the mounting flange.
1. Pull the rubber flap off the flap valve assembly.
B To replace the flap valve:
– Press the two lugs on the back of the flap into the
two slots in the flap valve assembly.
B Push the mixing chamber back onto the mounting
flange and twist anti-clockwise to secure.
Fig. 88 Flap valve assembly
AU/NZ
2.
1.
1.
4.
3.
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1.
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