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20
P/N 240010943, Rev. C [09/07/2016]
Minimum/Maximum Vent
Lengths
Model
4” (102mm) Pipe
Min.
6 Ft (1.8 m)
Max.
100 Ft (30.5 m)
6 - COMBUSTION AIR AND VENT PIPING
WARNING
Vent extending through exterior wall shall not
terminate adjacent to wall or below building
extensions such as eaves, balconies, parapets or
decks. Failure to comply could result in death or
serious injury.
!
6.4
Vent
Pipe Installation
• Minimum and maximum combustion air and vent pipe
lengths listed in Table 5. Pipe length counted from
combustion air connector to termination.
• 90° elbows equivalent to 5.0 ft (1.6 m). 45° elbows
equivalent to 3.5 ft (1.1 m).
•
Use flexible Polyproplyene piping (PP) in a vertical
position only. Check PP pipe manufacturer for details.
Each foot of PP flexible pipe is equivalent to 2
⅝
feet of
smooth pipe of same diameter.
• Slope vent pipes minimum 1/4" per foot (21 mm/m)
back toward boiler. Support horizontal sections to
prevent sags capable of accumulating condensate.
• Support piping in accordance with pipe manufacturer's
instruction and authority having jurisdiction. In absence
of manufacturer's instruction use pipe hooks, pipe
straps, brackets, or hangers of adequate and strength
located at intervals of 4 ft (1.2m) or less. Allow for
expansion/contraction of pipe.
• Combustion air and vent piping must be air tight and
water tight.
•
Certified vent system components must NOT be
interchanged with other vent systems or unlisted pipe/
fittings.
• Canadian installations only. All venting material, primer
and glue must be listed to ULC S636.
• Canadian installations only. First 3 ft (0.9 m) of
plastic vent pipe from vent connector must be readily
accessible for visual inspection.
6.5
Vent
Termination
•
Terminate combustion air and vent pipes with fittings
or concentric vent kit.
A. See "Parts, Kits and Optional Accessories" manual
for concentric vent kit part numbers.
B. Use horizontal pipe for vent and 90° elbow for
combustion air termination when using fittings.
• Separate vent terminal from air inlet terminal to
prevent flue gas recirculation. If T-Terminal is used on
flue pipe at sidewall, air inlet terminal shall be at least
36" or more away from vent terminal.
• Locate combustion air termination as far as possible
from swimming pool, swimming pool pump house, and
other sources of airborne chlorine.
• Locate combustion air and vent terminals as required
by authority having jurisdiction.
Table 5 - Combustion Air and Vent Piping Length
For Example: Boiler can be installed on outside wall and
vented with one 90° elbow and 1 ft (0.30 m) of vent pipe.
Table 6 -Equivalent Length of Venting Components
Equivalent Length of Venting Components
Component
Feet
Meters
90° Elbow
5
1.6
45° Elbow
3 1/2
1.1
2" x 4" Adapter
0
0
3" x 4" Adapter
0
0
Concentric Vent Kit
5
1.6
Polypropylene Flexible Pipe per Foot
2 5/8
0.8