45
At least 36 in.
18 in. maximum
Vertical separation
between combustion
air and vent
8 3/4 in. (222mm)for 3 in. (76mm)kit
6 3/4 in. (172mm)for 2 in. (51mm) kit
Roof Te rmination (Preferred)
Abandoned masonry
used as raceway
(per code)
At least
36 in.
A
Maintain 12
in.
min. clearance above
highest anticipated
snow level, maximum of
24 in. above roof
Concentric Vent and Combustion Air
Roof Termination (preferred)
1
in.
(25mm)
maximum (typ) from wall to inlet
12
in. (305mm)
minimum from
overhang or roof
Maintain 12
in.
min. clearance above
highest anticipated
snow level or grade
whichever is greater
A
A
t le
a
st
3
6
in
.
Concentric Vent
and Combustion - Air
Side Te rmination
A
At least 36 in.
Side wall ter mination
of less than 12
in. (305mm)
above highest snow level
12
in.
min from
overhang or roof
12
in.
(305mm)
separation between
bottom ofcombustion air and
bottom of vent (typ)
Maintain 12
in.
min. clearance above
highest anticipated
snow level or grade
whichever is greater (typ)
A
At least 36 in
.
A
Maintain 12 in. (305mm)min.
clearance above
highest anticipated
snow level
Maximum of 24 in.(614mm)
above roof
90°
Note: "A" denotes 0 to < 2 in.
Between the first 2 vents
Third vent must be > 36 in. away
(typ)
(
91
4m
m)
(305mm)
(914mm)
(305mm)
(305mm)
(914mm)
(914mm)
(457mm)
(51mm)
(914mm)
A05090
Fig. 44 -- Combustion Air and Vent Pipe Termination for Direct Vent (2--pipe) System
Abandoned masonry
used as raceway
(per code)
12 in. (305 mm) min. from
overhang or roof
Maintain 12 in. (305mm)
minimum clearance
above highest anticipated
snow level or grade
whichever is greater.
Side wall termination
with 2 elbows (preferred)
12 in. min. (305 mm)from
overhang or roof
Maintain 12 in. (305mm)
minimum clearance
above highest anticipated
snow level or grade
whichever is greater
6 in. (152mm) minimum clearance
between wall and end of vent pipe.
10 in. (254mm) maximum pipe length
Sidewall Te r mi na ti on
with Straight Pipe (preferred)
Roof Termination (Preferred)
Vent
Maintain 12 in .
minimum clearance
above highest anticipated
snow level maximum of
24 in. (610mm) above roof.
90°
(305mm)
A05091
Fig. 45 -- Vent Pipe Termination for Non-Direct Vent (1-pipe) System
353BAV