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6 - COMBUSTION AIR AND VENT PIPING
6.4 Concentric Venting Instructions
A.
General
• Examine all components for possible shipping damage,
prior to installation.
• Venting system must be free to expand and contract.
• Support venting system in accordance with these
instructions.
• Vent system must have unrestricted movement through
walls, ceilings and roof penetrations.
• Check for proper joint construction when joining pipe to
fittings.
• If vent is penetrating ceilings and floors, openings must
have means of firestopping in joist areas and proper
firestop spacer assemblies installed.
• Standard roof flashing methods must be employed to
install roof flashing.
• Wall and roof openings must be framed to provide support
attachment of termination assemblies.
• Slope vent pipes minimum 3/4" (2 cm/m) for every 3 ½ ft
(1.0 m) back toward boiler. Support horizontal sections to
prevent sags capable of accumulating condensate.
• For horizontal flues a minor deviation from the horizontal
is allowable, provided it results in a downward slope
towards the boiler. For the vertical flue termination, refer
to the separate installation instructions supplied with the
assembly.
• Use of additional flue components as follows:
Elbow
Total Length Reduction
45°
1' 8" (0.5 m)
90°
3' 4" (1.0 m)
Total flue length shall not exceed 21 ft (6.4 m) to include
allowance for elbows.
• Connect flue elbow to top of boiler and adjust direction of
elbow to desired orientation (rear, right or left).
• Measure distance from outside wall face to elbow. This
dimension will be known as 'X'. add distance "Y" + 2" (50
mm) to "X" this is the total dimension of the vents.
• Mark dimension from above on outer aluminum intake
vent. Measure length of waste material, and transfer
dimension to inner grey flue pipe.
WT
(X)
(X)
Wall Thickness
WT = Wall Thickness
FIGURE 6-2 Side Wall Concentric Venting
WARNING
• Covering non-metallic vent pipe and fittings with
thermal insulation shall be prohibited.
• Use of cellular core PVC for venting flue gas could
result in death, or serious injury.
• Concentric venting shall be fastened with screws.
Dual flue venting is NOT fastened with screws.
!
FIGURE 6-3 Roof Mount Concentric Venting
FIGURE 6-1
2” (50 mm)
X
Min. 8" (181 mm)
Max. 14" (356 mm)
Slope vent pipes
min. 3/4" (2 cm)
for every 3
¹
/
₂
ft.
(1.0m) back to
boiler
Maintain 12"(305mm)
US (18"(457mm)
Canada) clearance
above highest
anticipated snow level
24" (610mm) above
roof or ground
Ground
Anticipated
Snow Line
Ground
Anticipated
Snow Line
Maintain 12"(305mm)
US (18"(457mm)
Canada) clearance
above highest
anticipated snow level
24" (610mm) above
roof or ground
Anticipated
Snow Line
18" Vertical
Clearance to
ventilated soffit
P/N 240011664, Rev. E [09/15/2017]