Vent Pipe Connection To Blower; Coupling Installations According To Vent Sizes - Smith BTF-80 SERIES 210 Installation And Operating Manual

76mm (3 in.)
MIN. LENGTH
A VENT USED IN A
SPECIAL VENTING
SYSTEM WITH POSITIVE
VENT PRESSURE AND
PASSING THROUGH A
ROOF SHALL EXTEND
AT LEAST 458mm (18 in.)
ABOVE THE HIGHEST
POINT WHERE IT PASSES
THROUGH THE ROOF
SURFACE AND ANY
OTHER OBSTRUCTION
WITHIN A HORIZONTAL
DISTANCE OF 458mm
(18 in.). A VERTICAL
VENTING SYSTEM MUST
BE SUPPORTED EVERY
1.5m (5 ft.).
Figure 31

Vent pipe connection to blower

1. The CPVC vent piping connects into the rubber
coupling located on the top of the blower assembly.
This coupling includes gear clamps to connect the
venting to the blower. These connections must be
properly seated and tightened to prevent the leakage
of fl ue gases into the area. See Figure 32 thru Figure
34.
2. The water heater are supplied with a 3" rubber
coupling to accept the vent pipe. Note: Polypropylene
vent systems require separate adaptor.
3. Before installing clean and lightly sand the end of
the CPVC plastic vent piping that will connect into
the rubber coupling. For polypropylene vent systems
follow manufacturer's instructions.
4. Loosen the upper clamp on the rubber coupling
and insert the sanded end of the vent piping a full
32mm (1-1/4 in.). Do not use glue or sealant in the
rubber coupling. Check that there is no stress on the
connection or the vent piping that may be caused by
twisting or bending.
5. Tighten the upper clamp so that the vent piping is
fi rmly secured in the coupling and is gas tight. Do not
over tighten or cause distortion of any of the parts.
Ensure the bottom of the rubber coupling is fi rmly
seated on the blower outlet and that the lower gear
clamp is also secure. Check to ensure there is no
distortion or movement of the clamped assembly once
it is completed.
6. If the outlet vent pipe is to be turned horizontally
directly off the blower, a 76mm (3 in.) long section of
CPVC pipe may be cut from the 1.5m (5 ft.) (supplied)
section of 3" Schedule 40 CPVC vent pipe. This is to
be used to connect the CPVC outlet vent pipe elbow
to the water heater (see Figure 34). This elbow SHALL
be used in equivalent length calculations but does
NOT contribute to the fi rst 1.5m (5 ft.) of the outlet
vent system (see "Venting").
331432-00
TERMINATION
MAY BE 90°
ELBOW
458mm
RODENT
(18 in.) OR
SCREEN
ABOVE
(INSTALL
ANTICIPATED
INTO
SNOW LEVEL
ELBOW)
ROOF
LINE
CAUTION
Property Damage Hazard
• Do not overtighten the top and bottom gear clamps of the
rubber coupling.
• Do not apply solvent cement or silicone to the rubber
coupling connection.

Coupling installations according to vent sizes

CONFIGURATION
FOR HEATERS
CONNECTED TO
3" VENTING.
3" RUBBER
COUPLING
(SUPPLIED)
BLOWER
Figure 32
CONFIGURATION
FOR HEATERS
CONNECTED TO
4" VENTING.
3" RUBBER
COUPLING
(SUPPLIED)
BLOWER
Figure 33
3" CPVC
VENT PIPE
(SUPPLIED)
3" CPVC
VENT PIPE
(SUPPLIED)
BLOWER
Figure 34
3" CPVC
VENT PIPE
4" CPVC
VENT PIPE
3"-4" CPVC
ADAPTER
(FIELD
SUPPLIED)
3" CPVC
VENT PIPE,
76mm (3 in.)
MAX LENGTH
3" CPVC
ELBOW
(FIELD
SUPPLIED)
3" RUBBER
COUPLING
(SUPPLIED)
29