Bryant 340MAV Installation, Start-Up, And Operating Instructions Manual page 25

TABLE 6—APPROVED COMBUSTION-AIR AND VENT PIPE, FITTING AND CEMENT MATERIALS
ASTM SPECIFICATION
MATERIAL PIPE FITTINGS SOLVENT CEMENT AND PRIMERS
(MARKED ON MATERIAL)
D1527
D1785
D2235
D2241
D2466
D2468
D2564
D2661
D2665
F438
F441
F442
F493 For CPVC
F628
F656
F891
NOTE: The minimum combustion-air and vent pipe length (each)
for these furnaces is 5 ft. Short pipe lengths (5-8 ft) may discharge
water droplets. These droplets may be undesirable, and a 12-in.
minimum offset pipe section is recommended, as shown in Fig. 34,
to reduce excessive droplets from exiting vent pipe outlet.
B. Combustion-Air and Vent Pipe Diameter
Determine combustion-air and vent pipe diameter.
1. Using Table 7, individually determine the smallest
combustion-air and vent pipe diameters permitted for each
pipe. Pick the larger of these 2 pipe diameters and use this
diameter for both combustion-air and vent pipes.
NOTE: Select 1 vent pipe connection and
1 combustion-air pipe connection.
AIR
FLOW
COMBUSTION- COMBUSTION-
AIR AIR
VENT
VENT
UPFLOW
COMBUSTION-
AIR
VENT
AIR
FLOW
HORIZONTAL-LEFT DISCHARGE
Fig. 33—Combustion-Air and Vent Pipe Connections
ABS Pipe —
PVC Pipe —
For ABS — —
PVC Pipe —
PVC — Fittings
ABS — Fittings
For PVC — —
ABS Pipe Fittings
PVC Pipe Fittings
CPVC — Fittings
CPVC Pipe —
CPVC Pipe —
— —
ABS Pipe —
For PVC — —
PVC Pipe —
NOTE: Select 1 vent pipe connection and
1 combustion-air pipe connection.
VENT
VENT
COMBUSTION- COMBUSTION-
AIR AIR
AIR
FLOW
DOWNFLOW
COMBUSTION-
AIR
VENT
AIR
FLOW
HORIZONTAL-RIGHT DISCHARGE
A96187
—
—
Solvent
Cement
—
—
—
Solvent
Cement
—
—
—
—
—
Solvent
Cement
—
Primer
—
2. When installing vent systems of short pipe length, use the
smallest allowable pipe diameter. Do not use pipe size
greater than required or incomplete combustion, flame
disturbance, or flame sense lockout may occur.
NOTE: Do not count elbows or pipe sections in terminations or
within furnace. See shaded areas in Fig. 36, 37, 38, 39, and 40.
EXAMPLE:
An 036080 size furnace located in Indianapolis, elevation
650 ft above sea level, could be installed in an application
requiring 3 elbows and 32 ft of vent pipe, along with 5
elbows and 34 ft of combustion-air pipe. Table 7 indicates
this application would allow a 2-in. diameter vent pipe, but
require a 2-1/2 in. diameter combustion air pipe (2-in. 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. If same
installation were in Albuquerque, elevation 5250 ft above
sea level, installation would require 2-1/2 in. vent pipe and
combustion-air pipe. At 5001- to 6000-ft elevation, 2-in.
pipe is only good for 17 ft with 5 elbows, and 2-1/2 in. pipe
is good for 70 ft with 5 elbows.
C. Combustion-Air and Vent Pipe Attachment
NOTE: All pipe joints must be cemented except attachment of
combustion-air pipe to inlet housing connection, since it may be
necessary to remove pipe for servicing.
1. Attach combustion-air pipe as follows:
a. Determine location of combustion-air intake pipe con-
nection to combustion-air intake housing as shown in
Fig. 33 for application.
b. Reposition combustion-air intake housing plug fitting in
appropriate unused intake housing connection.
c. If required per Table 7, insert perforated disk assembly
(factory-supplied in loose parts bag) in intake housing
where combustion-air intake pipe will be connected. If
half disk set is required, install with shoulder of disk
against stop in combustion-air inlet.
—25—
DESCRIPTION
Schedule-40
Schedule-40
For ABS
SDR-21 & SDR-26
Schedule-40
Schedule-40
For PVC
DWV at Schedule-40 IPS sizes
DWV
Schedule-40
Schedule-40
SDR
For CPVC
Cellular Core DWV at Schedule-40 IPS sizes
For PVC
Cellular Core Schedule-40 & DWV