30
Vertical Termination
1. Fig. 24 shows the proper installation and clearances for
vertical vent termination. The vertical roof termination
should be sealed with a plumbing roof boot or equivalent
flashing. The inlet of the intake pipe and end of the ex-
haust vent must be terminated no less than 12
″
(305 mm)
above the roof or snow accumulation level, and 12
″
(305
mm) away from a vertical wall or other protrusion.
2. If the vent system is installed in an existing chimney make
sure clearances shown in Fig. 23 are maintained. Horizont-
al section before the termination elbow can be extended on
the inlet air to provide necessary clearance.
Multi Vent Termination Clearances
When two (2) or more furnaces are vented near each other, each
furnace must be individually vented.
Two (2) vent terminations may be installed as shown in Fig. 25,
26, 27, 28 and 29, but the next vent termination must be at least
36
″
(914 mm) away from first 2 terminations. It is important that
vent terminations be made as shown to avoid recirculation of flue
gases.
Combustion
Air
Exhaust
12
in.
(304.8mm)
Min. Grade or
Snow Level
36” Min.
2” (50.8mm) Max.
36” Min.
OR
(914.4mm)
(914.4mm)
A07718
Fig. 25 -- Concentric Vent and Combustion--Air
Roof Termination
“A”
Vent
Dimension “A” is touching or 2 in. (503.8mm) maximum separation.
25--22--02d
Vent
Combustion Air
Exhaust
1 in. (25.4mm)
Maximum
A07695
Fig. 26 -- Concentric Vent and Combustion Air
Sidewall Termination
Exhaust
“A”
“A”
Inlet
Dimension “A” is touching or 2 in. (50.8mm) maximum separation
8 in. (203.2mm)
Min.
18 in. (457.2mm) Min. for Cold Climates
[Sustained 0
°
F(- 17
°
C) and below for
24 hours or more consecutive hours]
12 in. (304.8mm) Min.
Grade or Snow Level
8 in. (203.2mm) Min.
20 in. (6.1m) Max.
A07696
Fig. 27 -- Sidewall Inlet Vent and Exhaust--Air Termination
Exhaust
Inlet
“A”
“A”
Dimension “A” is touching or 2 in. (503.8mm) maximum separation.
18 in. (457.2mm) Min. for Cold Climates
[Sustained 0
°
F(- 17
°
C) and below for
24 hours or more consecutive hours]
8 in. (203.2mm) Min.
20 in. (6.1m) Max.
8 in. (203.2mm) Min.
12 in. (457.2mm)
Min. Grade or
Snow Level
A07697
Fig. 28 -- Sidewall Inlet Vent and Exhaust--Air Termination
with Exterior Risers
Exhaust
25--22--43
Inlet
12 in. (304.8mm)
Min. Grade or
Snow Level
18 in. (457.2mm) Min. for Cold Climates
[Sustained 0
°
F(- 17
°
C) and below for
24 hours or more consecutive hours]
8 in. (203.2mm) Min.
20 in. (6.1m) Max.
A07698
Fig. 29 -- Rooftop Inlet Vent and Exhaust--Air Termination
359AA
V
