Bryant 350AAV Installation, Start-Up, And Operating Instructions Manual page 40

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EXAMPLE:
An 080-12 size furnace located in Indianapolis, elevation
650 ft above sea level, could be installed as either a direct
vent/2-pipe system that requires 3 elbows and 32 ft of vent
pipe, along with 5 elbows and 34 ft of combustion-air pipe
OR a non-direct vent/1-pipe system that requires 3 elbows
and 32 ft vent pipe.
For a direct vent/2-pipe system, Table 11 indicates this
application would allow a 2-in. diameter vent pipe, but
require a 2-1/2 in. diameter combustion air pipe. According
to Table 11, 2-in. diameter pipe is good for 35 ft with 3
elbows, but only 30 ft with 5 elbows. Therefore, 2-1/2 in.
diameter pipe must be used for both vent and combustion-
air pipes since larger required diameter must always be
used for both pipes.
For a non-direct vent/1-pipe system, Table 11 indicates that
this application would allow a 2-in. diameter vent pipe.
If same installations were in Albuquerque, elevation 5250 ft
above sea level:
For a direct vent/2-pipe system, Table 11 indicates that
2-1/2 in. diameter vent pipe and combustion-air pipe are
required.
For a non-direct vent/1-pipe system, Table 11 indicates that
2-1/2-in. diameter vent pipe is required.
If same applications are to be installed at 5001- to 6000 ft
elevation:
For a direct vent/2-pipe system, 2-in. pipe is only good for
23 ft (with 3 elbows) and 17 ft (with 5 elbows). Therefore,
2-1/2 in. diameter combustion air and vent pipe must be
used.
For a non-direct vent/1-pipe system, a 2-in. diameter pipe is
only good for 23 ft with 3 elbows. A 2-1/2-in. diameter vent
pipe must be used.
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G. Vent Termination
GENERAL
Combustion-air (direct vent/2-pipe system only) and vent pipe
must terminate outside structure, either through sidewall or roof.
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Roof Termination (Preferred)
Vent
Maintain 12 in.
minimum clearance
above highest anticipated
snow level maximum of
24 in. above roof.
Abandoned masonry
used as raceway
(per code)
12 in. min. from
overhang or roof
90°
Side wall termination
with 2 elbows (preferred)
Fig. 43—Vent Pipe Termination for Non-Direct
Vent (1-pipe) System (Sizes 040 Through 120 Only)
—40—
For vent termination clearance, refer to Table 8 for Direct
Vent/2-Pipe system and Table 9 for Non-direct Vent/1-Pipe
system. For exterior piping arrangements, refer to Fig. 42 for
Direct Vent/2-Pipe system and Fig. 43 for Non-Direct/1-Pipe
system.
Roof termination is preferred since it is less susceptible to damage
or contamination, and it has less visible vent vapors. Sidewall
termination require sealing or shielding of building surfaces with a
corrosive resistance material due to corrosive combustion products
of vent system.
NOTE: (Direct Vent/2-Pipe system ONLY) A factory accessory
termination kit MUST be used. See section "Vent Termination Kit
(Direct Vent/2-Pipe System Only)" in this instruction.
When determining appropriate location for termination, consider
the following guidelines:
1. Comply with all clearance requirements stated in Table 8 or
Table 9 per application.
2. Termination or termination kit should be positioned where
vent vapors will not damage plants/shrubs or air condition-
ing equipment.
3. Termination or termination kit should be positioned so that
it will not be affected by wind eddy, such as inside building
corners, nor by recirculation of flue gases, airborne leaves,
or light snow.
4. Termination or termination kit should be positioned where
it will not be damaged by or subjected to foreign objects
such as stones, balls, etc.
5. Termination or termination kit should be positioned where
vent vapors are not objectionable.
EXTENDED EXPOSED SIDEWALL PIPES
Sidewall combustion air pipe termination (direct vent/2-pipe
system only) and vent pipe termination may be extended beyond
area shown in Fig. 42 or in Fig. 43 per application in outside
ambient by insulating pipe as indicated in Table 10.
1. Determine combustion air pipe diameter (direct vent/2-pipe
system only) and vent pipe diameter, as stated above, using
total pipe length and number of elbows.
6 in. minimum clearance
between wall and end of vent pipe.
10 in. maximum pipe length
Maintain 12 in.
minimum clearance
above highest anticipated
snow level or grade
whichever is greater.
12 in. min. from
overhang or roof
Maintain 12 in.
minimum clearance
above highest anticipated
snow level or grade
whichever is greater
Sidewall Termination
with Straight Pipe (preferred)
A05091