Page 8
Downow Installation
Downow unit installs in three ways: on non-combustible
ooring, on combustible ooring using a downow com-
bustible ooring base, or on a reverse-ow cooling cabi-
net. Do not drag the unit across the oor.
Installation on Non-Combustible Flooring (Figure 6)
1 - Cut oor opening keeping in mind clearances listed
on unit rating plate. Also keep in mind gas supply
connections, electrical supply, ue and air intake
connections and sufcient installation and servicing
clearances. See table 1 for correct oor 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.
SUPPLY AIR
PLENUM
OPENING
FIGURE 6
TABLE 1
NON-COMBUSTIBLE FLOOR OPENING SIZE
Cabinet
Width
Front to Rear Side to Side
in mm in mm
A (14.5”)
19-3/4 502
13-1/4 337
B (17.5”) 16-3/4 413
C (21”) 19-3/4 502
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 oor,
a downow combustible ooring base must be
installed between the furnace and the oor. The
base must be ordered separately.
See table 2 for opening size to cut in oor.
CAUTION
The furnace and downow combustible ooring base
shall not be installed directly on carpeting, tile, or other
combustible material other than wood ooring.
SUPPLY AIR PLENUM
DOWNFLOW
COMBUSTIBLE
FLOORING BASE
PROPERLY
SIZED FLOOR
OPENING
FIGURE 7
TABLE 2
COMBUSTIBLE FLOOR OPENING SIZE
Cabinet
Width
Front to Rear Side to Side
in mm in mm
A (14.5”)
22 569
15-3/4 400
B (17.5”) 18-3/4 476
C (21”) 22-3/4
578
2 - After opening is cut, set combustible ooring base
into opening.
3 - Check sealing strips on combustible ooring base to
make sure they are properly glued and positioned.
4 - Lower supply air plenum into downow combustible
ooring base until plenum anges 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 s adequate.
Installation on Cooling Cabinet (Figure 8)
1 - Refer to reverse-ow coil installation instructions for
correctly sized opening in oor and installation of
cabinet.
NOTE - Downow combustible ooring 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.