Lennox EL296UHVX Series Unit Information page 54

Use the following steps to correctly size vent pipe diameter.
Piping Size Process
What is the
furnace capacity?
1
Which style termination
2
being used?
Standard or concentric?
Which needs
most elbows?
3
Intake or
exhaust?
How many elbows?
Count all elbows inside
4
and outside house.
5
Desired pipe size?
What is the altitude of
6
the furnace installation?
See max intake or exhaust
pipe length tables.
7
Includes all vent pipe and
elbows inside and outside
the house.
FIGURE 21
IMPORTANT
Do not use screens or perforated metal in exhaust or
intake terminations. Doing so will cause freeze-ups
and may block the terminations.
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