Use and Care Manual

507769C05Page 16 of 55
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Table 6. Minimum Vent Pipe Length
Capacity Min. Vent Length*
045, 070, 090, 110
15 ft. or
5 ft. plus 2 elbows or
10 ft. plus 1 elbow
* Any approved termination may be added to the minimum
length listed.
Do not use screens or perforated metal in exhaust or
intake terminations. Doing so will cause freeze-ups and
may block the terminations.
IMPORTANT
Use the following steps to correctly size vent pipe diameter.
045, 070,
090, 110
Standard or
Concentric?
See Table 5
Intake or
Exhaust?
1-1/2”, 2”,
2-1/2”, or 3”
Furnace capacity?
1
Which termination?
2
Which needs most
elbows?
3
How many?
4
Desired pipe size?
5
What is the altitude?
6
Use Table 7 to find
max pipe length.
7
Figure 21.