Lennox EL180DFE Installation Instructions Manual page 8

Downflow Installation
Downflow unit installs in three ways: on non-combustible
flooring, on combustible flooring using a downflow com­
bustible flooring base, or on a reverse-flow cooling cabinet.
Do not drag the unit across the floor.
Installation on Non-Combustible Flooring (Figure 6)
1 - Cut floor opening keeping in mind clearances listed on
unit rating plate. Also keep in mind gas supply connec­
tions, electrical supply, flue and air intake connections
and sufficient installation and servicing clearances.
See table 1 for correct floor opening size.
2 - Flange warm air plenum and lower the plenum into the
opening.
3 - Set the unit over the plenum and seal the plenum to
the unit.
4 - Ensure that the seal is adequate.
EL180DFE UNIT
OPENING
FIGURE 6
TABLE 1
NON-COMBUSTIBLE FLOOR OPENING SIZE
Front to Rear
Cabinet Width
in.
A (14.5") 19-3/4
B (17.5") 19-3/4
C (21") 19-3/4
NOTE - Floor opening dimensions listed are 1/4 inch (6 mm) larger than
the unit opening. See unit dimensions on page 2.
Installation on Combustible Flooring (Figure 7)
1 - When unit is installed on a combustible floor, a down­
flow combustible flooring base must be installed be­
tween the furnace and the floor. The base must be or­
dered separately.
See table 2 for opening size to cut in floor.
SUPPLY AIR
PLENUM
Side to Side
mm in. mm
502 13-1/4 337
502 16-1/4 413
502 19-3/4 502
The furnace and downflow combustible flooring
base shall not be installed directly on carpeting, tile,
or other combustible material other than wood floor­
ing.
EL180DFE UNIT
PROPERLY
SIZED FLOOR
OPENING
COMBUSTIBLE FLOOR OPENING SIZE
Cabinet Width
A (14.5")
B (17.5")
C (21")
2 - After opening is cut, set combustible flooring base into
opening.
3 - Check sealing strips on combustible flooring base to
make sure they are properly glued and positioned.
4 - Lower supply air plenum into downflow combustible
flooring base until plenum flanges seal against the
strips.
NOTE - Be careful not to damage sealing strips. Check
for a tight seal.
5 - Set the furnace over the plenum.
6 - Ensure that the seal between the furnace and plenum
is adequate.
Installation on Cooling Cabinet (Figure 8)
1 - Refer to reverse-flow coil installation instructions for
correctly sized opening in floor and installation of cabi­
net.
NOTE - Downflow combustible flooring kit is not used
2 - When cooling cabinet is in place, set and secure the
furnace according to the instructions that are provided
with the cooling coil. Secure the furnace to the cabinet.
3 - Seal the cabinet and check for air leaks.
Page 8
CAUTION
SUPPLY AIR PLENUM
DOWNFLOW
COMBUSTIBLE
FLOORING BASE
FIGURE 7
TABLE 2
Front to Rear Side to Side
in. mm in.
22 559 15-3/4
22 559 18-3/4
22 559 22-3/4
mm
400
476
578