Carrier 58MXA Installation, Start-Up, And Operating Instructions Manual page 28

TABLE 6—MAXIMUM ALLOWABLE PIPE LENGTH (FT) (Continued)
ALTITUDE (FT) UNIT SIZE
040-08
040-12
060-08
060-12
060-16
080-12
080-16
8001 to 9000‡
080-20
100-16
100-20
120-20
140-20
ALTITUDE (FT) UNIT SIZE
040-08
040-12
060-08
060-12
060-16
080-12
080-16
9001 to 10,000‡
080-20
100-16
100-20
120-20
140-20
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.
12. Support combustion-air and vent piping a minimum of every
5 ft (3 ft for SDR-21 or -26 PVC) using perforated metal
hanging strap.
13. Slope combustion-air and vent pipes toward furnace a mini-
mum of 1/4 in. per linear ft with no sags between hangers.
14. Use appropriate methods to seal openings where vent and
combustion-air pipes pass through roof or side wall.
CONCENTRIC VENT AND COMBUSTION-AIR TERMINA-
TION KIT INSTALLATION
NOTE: If these instructions differ from those packaged with
termination kit, follow kit 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. 30, 31, 32, 33, and 34. 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.
TERMINATION PIPE DIA
TYPE (IN.)*
1-1/2
2 Pipe or 2-in
Concentric
2
1-1/2
2 Pipe or 2-in
Concentric
2
2
2 Pipe or 2-in
Concentric
2-1/2
2-1/2
2 Pipe or 3-in
Concentric
3
3† no disk
2 Pipe or 3-in.
Concentric
4† no disk
TERMINATION PIPE DIA
TYPE (IN.)*
1-1/2
2 Pipe or 2-in
Concentric
2
2 Pipe or 2-in
2
Concentric
2
2 Pipe or 2-in
Concentric
2-1/2
2-1/2
2 Pipe or 3-in
Concentric
3
2 Pipe or 3-in.
4† no disk
Concentric
28
NUMBER OF 90° ELBOWS
1 2 3
46 41 36
62 60 58
11 6 NA
49 44 42
33 28 17
62 60 58
23 15 7
59 54 49
10 NA NA
35 30 25
NA
NUMBER OF 90° ELBOWS
1 2 3
42 37 32
57 55 53
45 40 38
30 25 14
57 55 53
21 13 5
54 49 44
10 5 NA
NA
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 penetration
of wall or roof is desired.
NOTE: Shaded parts in Fig. 30, 31, 32, 33, and 34 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. 30 or
31.) 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. 33 or 34 in outside ambient by
insulating pipes as indicated in Table 7.
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 furnace
model.
3. Determine required insulation thickness for exposed pipe
lengths.
4 5 6
31 29 24
56 55 53
NA NA NA
37 35 34
12 10 NA
56 55 53
5 NA NA
44 39 34
NA NA NA
20 15 10
4 5 6
27 25 20
51 49 47
33 31 29
9 7 NA
51 49 47
NA NA NA
39 34 29
NA NA NA