Lennox EL196UHE Series Information page 29

Intake Piping
The EL196UHE furnace may be installed in either direct
vent or non-direct vent applications. In non-direct vent ap-
plications, when intake air will be drawn into the furnace
from the surrounding space, the indoor air quality must be
considered and guidelines listed in Combustion, Dilution
and Ventilation Air section must be followed.
Follow the next two steps when installing the unit in Di-
rect Vent applications, where combustion air is taken from
outdoors and flue gases are discharged outdoors. The
provided air intake screen must not be used in direct vent
applications (outdoors).
1 - Use transition solvent cement or a sheet metal screw
to secure the intake pipe to the inlet air connector.
2 - 2 - Route piping to outside of structure. Continue
with installation following instructions given in
general guidelines for piping terminations and
intake and exhaust piping terminations for direct
vent sections. Refer to TABLE 13 for pipe sizes.
Follow the next two steps when installing the unit in Non-
Direct Vent applications where combustion air is taken
from indoors and flue gases are discharged outdoors.
1 - Use field-provided materials and the factory-
provided air intake screen to route the intake piping
as shown in FIGURE 28 or FIGURE 29. Maintain
a minimum clearance of 3" (76mm) around the
air intake opening. The air intake opening (with
the protective screen) should always be directed
forward or to either side in the upflow position, and
either straight out or downward in the horizontal
position.The air intake piping must not terminate
too close to the flooring or a platform. Ensure
that the intake air inlet will not be obstructed by
loose insulation or other items that may clog the
debris screen.
2 - If intake air is drawn from a ventilated attic (FIGURE
30) or ventilated crawlspace (FIGURE 31) the
exhaust vent length must not exceed those listed
in TABLE 6. If 3" diameter pipe is used, reduce
to 2" diameter pipe at the termination point to
accommodate the debris screen.
3 - Use a sheet metal screw to secure the intake pipe
to the connector, if desired.
TYPICAL AIR INTAKE PIPE CONNECTIONS
Min 2"
NOTE - Debris screen and elbow may be rotated, so that
screen may be positioned to face forward or to either side.
TYPICAL AIR INTAKE PIPE CONNECTIONS
HORIZONTAL NON−DIRECT VENT APPLICATIONS
(Horizontal Right−Hand Air Discharge Application Shown)
NOTE - Debris screen may be positioned straight out
(preferred) or with an elbow rotated to face down.
Page 29
UPFLOW NON−DIRECT
VENT APPLICATIONS
INTAKE
DEBRIS
SCREEN
(Provided)
FIGURE 28
PVC pipe
Min 2"
(Provided)
FIGURE 29
coupling
OR
INTAKE
DEBRIS
SCREEN