Lennox ELITE Series Installation Instructions Manual page 18

Piping Size Process
What is the
furnace capacity?
1
Which style termination
being used?
2
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 and min length
tables. Include all vent pipe
7
and elbows inside and
outside the hpouse
Figure 23
Do not use screens or perforated metal in exhaust or
intake terminations. Doing so will cause freeze-ups and
may block the terminations.
Page 18
IMPORTANT