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Table 7—Maximum Allowable Pipe Length (ft)
ALTITUDE (FT) | UNIT SIZE | TERMINATION | PIPE DIA |
|
| NUMBER OF 90° ELBOWS |
| ||||
TYPE | (IN.)* | 1 | 2 |
| 3 | 4 |
| 5 | 6 | ||
|
|
|
| ||||||||
| 042040 | 2 Pipe or | 50 | 45 |
| 40 | 35 |
| 30 | 25 | |
| Concentric | 2 | 70 | 70 |
| 70 | 70 |
| 70 | 70 | |
|
|
|
| ||||||||
| 042060 | 2 Pipe or | 50 | 45 |
| 40 | 35 |
| 30 | 25 | |
| Concentric | 2 | 70 | 70 |
| 70 | 70 |
| 70 | 70 | |
|
|
|
| ||||||||
| 042080 | 2 Pipe or | 30 | 25 |
| 20 | 15 |
| 10 | 5 | |
0 to 2000 | 060080 | Concentric | 2 | 70 | 70 |
| 70 | 70 |
| 70 | 70 |
| 060100 | 2 Pipe or | 2 | 45 | 40 |
| 35 | 30 |
| 25 | 20 |
| Concentric | 70 | 70 |
| 70 | 70 |
| 70 | 70 | ||
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|
|
| ||||||||
|
| 2 Pipe or | 10 | NA |
| NA | NA |
| NA | NA | |
| 060120 | 3 | 35 | 30 |
| 15 | NA |
| NA | NA | |
| Concentric |
|
| ||||||||
|
| 3† | 70 | 70 |
| 70 | 70 |
| 70 | 70 | |
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ALTITUDE (FT) | UNIT SIZE | TERMINATION | PIPE DIA |
|
| NUMBER OF 90° ELBOWS |
|
| |||
TYPE | (IN.)* | 1 | 2 |
| 3 | 4 |
| 5 | 6 | ||
|
|
|
| ||||||||
| 042040 | 2 Pipe or | 45 | 40 |
| 35 | 30 |
| 25 | 20 | |
| Concentric | 2 | 70 | 70 |
| 70 | 70 |
| 70 | 70 | |
|
|
|
| ||||||||
| 042060 | 2 Pipe or | 45 | 40 |
| 35 | 30 |
| 25 | 20 | |
| Concentric | 2 | 70 | 70 |
| 70 | 70 |
| 70 | 70 | |
|
|
|
| ||||||||
2001 to 3000 | 042080 | 2 Pipe or | 26 | 21 |
| 16 | 11 |
| 6 | NA | |
060080 | Concentric | 2 | 70 | 70 |
| 70 | 70 |
| 70 | 70 | |
|
|
| |||||||||
| 060100 | 2 Pipe or | 2 | 40 | 35 |
| 30 | 25 |
| 20 | 15 |
| Concentric | 70 | 70 |
| 70 | 70 |
| 70 | 70 | ||
|
|
|
| ||||||||
| 060120 | 2 Pipe or | 3 | 31 | 26 |
| 12 | NA |
| NA | NA |
| Concentric | 3† | 63 | 62 |
| 62 | 61 |
| 61 | 61 | |
|
|
|
| ||||||||
ALTITUDE (FT) | UNIT SIZE | TERMINATION | PIPE DIA |
|
| NUMBER OF 90° ELBOWS |
|
| |||
TYPE | (IN.)* | 1 | 2 |
| 3 | 4 |
| 5 | 6 | ||
|
|
|
| ||||||||
| 042040 | 2 Pipe or | 42 | 37 |
| 32 | 27 |
| 22 | 17 | |
| Concentric | 2 | 70 | 70 |
| 70 | 70 |
| 70 | 70 | |
|
|
|
| ||||||||
| 042060 | 2 Pipe or | 42 | 37 |
| 32 | 27 |
| 22 | 17 | |
| Concentric | 2 | 70 | 70 |
| 70 | 70 |
| 70 | 70 | |
|
|
|
| ||||||||
3001 to 4000 | 042080 | 2 Pipe or | 25 | 20 |
| 15 | 10 |
| 5 | NA | |
060080 | Concentric | 2 | 70 | 70 |
| 70 | 70 |
| 70 | 70 | |
|
|
| |||||||||
| 060100 | 2 Pipe or | 2 | 38 | 33 |
| 28 | 23 |
| 18 | 13 |
| Concentric | 70 | 70 |
| 70 | 70 |
| 70 | 70 | ||
|
|
|
| ||||||||
| 060120 | 2 Pipe or | 3 | 29 | 24 |
| 10 | NA |
| NA | NA |
| Concentric | 3† | 59 | 59 |
| 58 | 57 |
| 57 | 56 | |
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See notes at end of table.
NOTE: Do not count elbows or pipe sections in terminations or within furnace. See shaded areas in Fig. 40, 41, 42, 43, and 44.
EXAMPLE: An 042080 size furnace located in Indianapolis, elevation 650 ft above sea level, could be installed in an application requiring 3 elbows and 17 ft of vent pipe, along with 5 elbows and 16 ft of
COMBUSTION-AIR AND VENT PIPE ATTACHMENT
NOTE: All pipe joints must be watertight except attachment of
1.Attach
a.Determine location of
b.Reposition
c.If required, insert perforated disk assembly
d.Install pipe support
e.Insert
f.Install casing hole filler cap