Lennox ELITE Series Installation Instructions Manual page 16

Horizontal Installation Offset Requirements
Exhaust Pipe
12" Max.
Horizontal
Gas Furnace
NOTE -
ward unit. A minimum of 1/4" (6mm) drop for each 12" (305mm)
of horizontal run is mandatory for drainage.
NOTE - Exhaust pipe MUST be glued to furnace exhaust fitting,
unless the optional glueless vent adapter kit 17H92 is used..
NOTE - Exhaust piping should be checked carefully to make
sure there are no sags or low spots.
FIGURE 23
TABLE 3
MINIMUM VENT PIPE LENGTHS
EL296UHE MODEL
045, 070, 090, 110, 135
*Any approved termination may be added to the minimum length list-
ed. Two 45 degree elbows are equivalent to one 90 degree elbow.
NOTE - Lennox offers a glueless vent adapter kit 17H92
as an option for exhaust exiting at the furnace top cap
coupling If the kit is not used, the exhaust pipe MUST be
glued to the furnace exaust fitting.
12" Min.
MIN. VENT LENGTH*
15 ft. or 5 ft plus 2 elbows or
10 ft plus 1 elbow
1
2
3
How many elbows?
4
Count all elbows inside
and outside house.
5
What is the altitude of
6
the furnace installation?
7
Do not use screens or perforated metal in exhaust or
intake terminations. Doing so will cause freeze-ups and
may block the terminations.
Page 16
Piping Size Process
What is the
furnace capacity?
045, 070, 090,
110 or 135?
Which style termination
being used?
Standard or concentric?
See table 3.
Which needs
most elbows?
Intake or
exhaust?
Desired pipe size?
2", 2-1/2", 3"
Use table 5 or 6 to find
max intake or exhaust pipe
length. Includes all vent
pipe and elbows inside
and outside the house.
FIGURE 24
IMPORTANT