Coaxial - Dunkirk DMG-240 Installation, Operation & Maintenance Manual

!
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.

6.5 Coaxial

A. Venting Instructions
Maximum Length = L
A B
E F
Coaxial Elbows - Equivalent length
Elbow
45°
90°
Illustration shows examples of maximum equivalent lengths.
B. Coaxial Flue Options
• Standard horizontal termination is suitable only for
horizontal applications.
• Maximum permissible equivalent vent length is 21 ft.
(6.4 m)
• An "in line" elbows in flue system must be taken into
consideration
6 - COMBUSTION AIR AND VENT PIPING
21' (6.4 m)
21' (6.4 m)
Total Length Reduction
1' 8" (0.5 m)
3' 4" (1.0 m)
L = L1 + L2
L2
L1
FIGURE 6-1 Side Wall Concentric Venting
2" (50 mm)
Slope vent pipes
min. 3/4" (2 cm)
for every 3¹/₂ ft.
(1.0m) back to
boiler
FIGURE 6-2 Roof Mount Concentric Venting
• The first elbow in horizontal run is NOT included in any
equivalent length calculations
Elbow
45°
90°
22
18" Vertical
Clearance to
ventilated soffit
X
Min. 8" (181 mm)
Max. 14" (356 mm)
Maintain 12"(305mm)
US (18"(457mm)
Canada) clearance
above highest
anticipated snow level
24" (610mm) above
roof or ground
Maintain 12"(305mm)
US (18"(457mm)
Canada) clearance
above highest
anticipated snow level
Anticipated
Snow Line 24" (610mm) above
roof or ground
Total Length Reduction
1' 8" (0.5 m)
3' 4" (1.0 m)
P/N 240011656, Rev. E [07/30/2018]
Anticipated
Snow Line
Ground
Anticipated
Snow Line
Ground