35
6 - COMBUSTION AIR AND VENT PIPING
Exhaust and combustion air intake are located in same general
location and are of equal length.
Twin Pipe Maximum Vent
Equivalent Lengths
Terminating in same
location
125/150
160/200
3" [80 mm]
3" [80 mm]
100 ft
100 ft
Note: Twin Pipe Common Atmospheric Zone termination
can be run horizontal or vertical
FIGURE 6-13-TWIN PIPE ROOF VENT
15"
(381mm)
Max.
Vent Combustion
Air
12" (305mm) US,
18" (458mm) Canada
Min. Above
Anticipated Snow Line
Roof Line
12" (305mm) Min.
FIGURE 6-14 - HORIZONTAL TWIN PIPE, EXHAUST AND
INTAKE
12" (305mm)
Minimum Separation
Manufacturer
Recommends
Greater Separation
PN 240012363 REV. A [08/31/2018]