Combustion-Air And Vent Piping - Bryant H Series Installation, Start-Up, And Operating Instructions Manual

Above grade level or above
anticipated snow depth
Dryer/Water heat vent
From plumbing vent stack
From any mechanical fresh air intake
For furnaces with an input capacity of
100,000 Btuh or less—from any non-
mechanical air supply (windows or doors
which can be opened) or combustion-air
For furnaces with an input capacity greater
than 100,000 Btuh—from any non-
mechanical air supply (windows or doors
which can be opened) or combustion-air
From service regulator vent, electric and
gas meters and relief equipment
Above grade when adjacent to public
† 18 in. above roof surface in Canada.
NOTES:
1. If installing 2 adjacent Furnaces, refer to Multiventing and Vent Terminations section for proper vent configurations.
2. When locating combustion-air and vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the
appliance's own flue products or the flue products of adjacent vents. Recirculation can cause poor combustion, inlet condensate problems, and accelerated corrosion of heat
exchangers.
3. Vent termination can not terminate less than 2 ft horizontal and 7 ft above public walkway or where condensate vapor or droplets may be a hazard.
4. Vent termination must be at least 3 feet above any forced draft inlets within 10 feet horizontal. Vent termination must be at least 3 feet horizontal from other direct vent
appliances intake unless otherwise specified by manufacturer. 5. 3 ft radius of furnace air-intake terminal and 1 ft horizontally from vertical centerline of furnace air-intake
terminal.
6. Above a meter/regulator within 3 feet horizontally of vertical centerline of meter/regulator vent outlet to a maximum vertacal distance of 15 feet.
Vent system or vent connectors may need to be resized. For any
other appliances when resizing vent systems or vent connectors,
system or connector must be sized to approach minimum size as
determined using appropriate table found in the NFGC or NSC-
NGPIC.
B. Combustion-Air and Vent Piping
GENERAL
Combustion-air and vent pipe, fittings, primers, and solvents must
conform to American National Standards Institute (ANSI) stan-
dards and American Society for Testing and Materials (ASTM)
standards. See Table 6 for approved materials for use in the U.S.A.
and Canada. In Canada construct all combustion-air and vent pipes
for this unit of CSA or ULC listed schedule-40 PVC, PVC-DWV
or ABS-DWV pipe and pipe cement. SDR pipe is NOT approved
in Canada.
See Table 7 for maximum pipe lengths and Fig. 36, 37, 38, 39, and
40 for exterior piping arrangements.
NOTE: Furnace combustion-air and vent pipe connections are
sized for 2-in. pipe. Any pipe size change should be made outside
furnace casing in vertical pipe. (See Fig. 32.) This allows proper
drainage of vent condensate.
Combustion-air and vent pipes must terminate together in same
atmospheric pressure zone, either through roof or sidewall (roof
termination preferred), using accessory termination kit. See Table
5 for required clearances.
Furnace combustion-air and vent pipe connections must be at-
tached as shown in Fig. 33. Combustion-air intake plug fitting and
inducer housing alternate vent cap may need to be relocated in
some applications.
NOTE: Slope combustion-air and vent pipes a minimum of
1/4-in. per linear ft with no sags between hangers.
TABLE 5—COMBUSTION-AIR AND VENT PIPE
TERMINATION CLEARANCES
LOCATION
opening
opening
walkway
U.S.A.
1
See Note 5
3
See Note 4
1
1
See Note 6
See Note 3
NOT IN
HORIZONTAL
SECTION
Fig. 32—Combustion-Air and Vent Pipe Diameter
Transition Location and Elbow Configuration
CAUTION: When combustion-air pipe is installed
above a suspended ceiling, pipe must be insulated with
3/8-in. thick Armaflex-type insulation. Combustion-air
pipe should also be insulated when it passes through
warm, humid space.
An abandoned masonry chimney may be used as a raceway for
properly insulated and supported combustion-air and vent pipes.
Each furnace must have its own set of combustion-air and vent
pipes and be terminated individually, as shown in Fig. 42.
Other gas appliances with their own venting system may also use
the abandoned chimney as a raceway providing it is permitted by
local code, the current edition of the NFGC or NSCNGPIC, and
the vent or liner manufacturer's Installation Instructions. Care
must be taken to prevent the exhaust gases from one appliance
from contaminating the combustion air of other gas appliances.
—24—
CLEARANCE (FT)
Canada
1†
See Note 5
3
6
1
3
See Note 6
See Note 3
FURNACE
PIPE DIAMETER
TRANSITION IN
VERTICAL SECTION
A93034