Bosch C 1210 ES Installation Manual page 19

Backdraft reducer
The Heat Fab backdraft reducer (9301BFP) is the pre-
ferred option for limiting backdraft (see Fig. 20).
Fig. 20 Part nr 9301BFP
Installation
For this solution to be effective, the internal flapper must
be 100% closed when the water heater is not running.
Refer to Fig. 22 and 23 for preferred installation posi-
tions in the vent system.
Installation considerations:
• Install damper per the supplied manufacturer's
instructions.
• The damper is only to be used in the exhaust vent
piping.
• Ensure directional arrow on damper label faces in the
same direction as exhaust flow.
• If installed horizontally, the axis must be horizontal or
slightly pitched up towards termination to ensure
damper closes 100% when heater is not running.
• To allow accessibility, damper must not be installed
in an enclosed section of vent pipe.
• Do not install damper in unconditioned spaces (e.g.
attics) Condensation can build up while the heater is
running which can later freeze and potentially block
the flapper.
Fig. 21 Blackflow reducer (9301BFP) installed
6 720 644 887
6720608643-18.1V
Fig. 22
Preferred damper position for vertical terminations
6720608643-19.1V
Fig. 23
Installation instructions
Unconditioned
space. Do not
install damper.
Enclosed vent
pipe. Do not
install damper.
6720608836-30.2V
6720608542-06.2V
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