Operating instructions

Combustion-air and vent pipes must terminate outside structure. A
factory accessory termination kit must be installed in 1 of the
installations shown in Fig. 36, 37, 38, 39, and 40. Four termination
kits are available.
1. The 2-in. termination bracket kit is for 1-in., 1-1/2 in., and
2-in. diameter 2-pipe termination systems.
2. The 3-in. termination bracket kit is for 2-1/2 in., 3-in., and
4-in. diameter 2-pipe termination systems.
3. The 2-in. concentric vent/air termination kit is for 1-in.,
1-1/2 in., 2-in., and 2-1/2 in. diameter pipe systems when
single penetration of wall or roof is desired.
4. The 3-in. concentric vent/air termination kit is for 2-1/2 in.,
3-in., and 4-in. diameter pipe systems when single penetra-
tion of wall or roof is desired.
NOTE: Shaded parts in Fig. 36, 37, 38, 39, and 40 are considered
to be termination. These components should NOT be counted
when determining pipe diameter. Roof termination is preferred
since it is less susceptible to damage, has reduced chances to take
in contaminants, and has less visible vent vapors. (See Fig. 36 or
37.) Sidewall termination may require sealing or shielding of
building surfaces with a corrosive resistance material due to
corrosive combustion products of vent system.
EXTENDED EXPOSED SIDEWALL PIPES
Sidewall combustion-air and vent pipe terminations may be
extended beyond area shown in Fig. 39 or 40 in outside ambient by
insulating pipes as indicated in Table 8.
1. Determine combustion-air and vent pipe diameters, as
stated above, using total pipe length and number of elbows.
2. Using winter design temperature (used in load calculations),
find appropriate temperature for your application and fur-
nace model.
3. Determine required insulation thickness for exposed pipe
lengths.
NOTE: Pipe length (ft) specified for maximum pipe lengths
located in unconditioned spaces. Pipes located in unconditioned
space cannot exceed total allowable pipe length as specified in
Table 7.
TWO-PIPE TERMINATION KIT
1. Determine location for termination.
Consideration of the following should be made when
determining an appropriate location for termination kit.
a. Comply with all clearance requirements as stated in
Table 5.
b. Termination kit should be positioned where vent vapors
will not damage plants/shrubs or air conditioning equip-
ment.
c. Termination kit should be positioned so that it will not be
affected by wind eddy (such as inside building corners)
or allow recirculation of flue gases, airborne leaves, or
light snow.
TABLE 7—MAXIMUM ALLOWABLE PIPE LENGTH (FT) (CONTINUED)
ALTITUDE (FT) UNIT SIZE
TERMINATION
TYPE
PIPE DIA
(IN.)*
NUMBER OF 90° ELBOWS
123456
8001 to 9000‡
024040
036040
2 Pipe or 2-in
Concentric
1-1/2 46 41 36 31 29 24
2 626058565553
024060
036060
048060
2 Pipe or 2-in
Concentric
1-1/2 11 6 NA NA NA NA
2 494442373534
036080
048080
060080
2 Pipe or 2-in
Concentric
2 3328171210NA
2-1/2 62 60 58 56 55 53
048100
060100
2 Pipe or 3-in
Concentric
2-1/2 23 15 7 5 NA NA
3 595449443934
060120
2 Pipe or 3-in.
Concentric
3† no disk 10 NA NA NA NA NA
4† no disk 35 30 25 20 15 10
060140 NA
ALTITUDE (FT) UNIT SIZE
TERMINATION
TYPE
PIPE DIA
(IN.)*
NUMBER OF 90° ELBOWS
123456
9001 to 10,000‡
024040
036040
2 Pipe or 2-in
Concentric
1-1/2 42 37 32 27 25 20
2 575553514947
024060
036060
048060
2 Pipe or 2-in
Concentric
2 454038333129
036080
048080
060080
2 Pipe or 2-in
Concentric
230251497NA
2-1/2 57 55 53 51 49 47
048100
060100
2 Pipe or 3-in
Concentric
2-1/2 21 13 5 NA NA NA
3 544944393429
060120
2 Pipe or 3-in.
Concentric
4† no disk 10 5 NA NA NA NA
060140 NA
Disk usage-Unless otherwise specified, use perforated disk assembly (factory-supplied in loose parts bag). If one disk is stated, separate 2 halves of perforated disk
assembly and use shouldered disk half. When using shouldered disk half, install screen side toward inlet box.
†Wide radius elbow.
‡Vent sizing for Canadian installations over 4500 ft (1370 m) above sea level are subject to acceptance by the local authorities having jurisdiction.
NA-Not Allowed; pressure switch will not make.
NOTES:
1. Do not use pipe size greater than those specified in table or incomplete combustion, flame disturbance, or flame sense lockout may occur.
2. Size both the combustion-air and vent pipe independently, then use the larger diameter for both pipes.
3. Assume two 45° elbows equal one 90° elbow. Long radius elbows are desirable and may be required in some cases.
4. Elbows and pipe sections within the furnace casing and at the vent termination should not be included in vent length or elbow count.
5. The minimum pipe length is 5 ft for all applications.
6. Use 3-in. diameter vent termination kit for installations requiring 4-in diameter pipe.
—30—