Page 10
The unit may be installed three ways in downflow applica
-
tions: on non-combustible flooring, on combustible floor
-
ing using an additive base, or on a reverse-flow cooling
coil cabinet.
Do not drag the unit across the floor in the
downflow position. Floor and furnace flange damage
will result.
Refer to FIGURE 13 for clearances in down-
flow applications.
Downflow Application Installation Clearances
Top
Bottom
Left Side
Right Side
Top
0
*Front
0
Back
0
Sides
0†
Vent
0
Floor
NC
‡
*Front clearance in alcove installation must be 24 in. (610 mm).
Maintain a minimum of 24 in. (610 mm) for front service access.
†Allow proper clearances to accommodate condensate trap and
vent pipe installation.
‡
tional base is installed between the furnace and the combustible
floor.
FIGURE 13
Installation on Non-Combustible Flooring FIGURE 14
1 -
Cut floor opening keeping in mind clearances listed
on unit rating plate. Also keep in mind gas supply
connections, 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.
TABLE 1
NON-COMBUSTIBLE FLOOR OPENING SIZE
Cabinet
Width
Front to Rear
Side to Side
in.
mm
in
mm
B (17.5”)
19-3/4
502
16-5/8
422
C (21”)
19-3/4
502
20-1/8
511
NOTE - Floor opening dimensions listed are 1/4 inch (6 mm) larger than
the unit opening. See dimension drawing on page 2.
SUPPLY AIR
PLENUM
PROPERLY
SIZED FLOOR
OPENING
FURNACE
FIGURE 14
Installation on Combustible Flooring FIGURE 15
1 -
When unit is installed on a combustible floor,
a downflow combustible flooring base must be
installed between the furnace and the floor. The
base must be ordered separately. See TABLE 2 for
opening size to cut in floor.
CAUTION
The furnace and combustible flooring base shall not be
installed directly on carpeting, tile, or other combustible
material other than wood flooring.