ICP 8MPT Installation Insrtuctions page 28

FIRE HAZARD
Failure to install furnace on noncombustible
subbase could result in personal injury, death
and/or property damage.
Place furnace on noncombustible subbase on
downflow applications, unless installing on
non-combustible flooring.
Sub-Bases for Combustible Floors - Furnace Only
Note: When using the subbase for combustible floors, the dis-
charge air duct flanges on the furnace MUST be broken down to
provide proper fit up to the subbase. Use duct pliers to bend the
duct flanges flat onto the furnace casing. DO NOT bend the duct
flanges inward (toward the heat exchangers) as air flow restric-
tions may occur.
The Sub-base for Combustible Floors MUST be used when a
downflow furnace is set on a combustible floor, even when the fur-
nace is installed on a coil box.
1. Cut the opening in the floor according to the dimensions in
Table 7 because the base is equipped with locating tabs that
center the base over the opening.
The opening in the base is 11/4" (31.8mm) shorter and 11/8"
(28.6mm) narrower than the minimum required size of the
opening in the floor. This is done to maintain a 1" clearance
between the floor and the plenum.
2. Fabricate the plenum to the dimensions given in Table 7.
Note that the dimensions given are outside dimensions.
3. Set the base over the opening in the floor, centering the open-
ing in the base over the opening in the floor. Fasten the base
to the floor with screws or nails. See Figure 28 and
Figure 29.
4. Drop the plenum through the opening in the base. The flange
of the plenum should rest on top of the combustible floor
base.
Sub-bases for Combustible Floors Dimensions in(mm)
Sub-base for
Combustible Floors
Part Number H*
Subbase for Furnace Only
NAHH001SB
NAHH002SB
NAHH003SB
Subbase for Coil Box
NAHH004SB
NAHH005SB
NAHH006SB
1511/16
(398.5)
195/16
(490.5)
221b/16
(582.6)
153/4
(25.4)
193/8
(181.1)
23 (284.2)
Sub-base for Combustible
Floor Dimensions
J_
283/4(730.3)
283/4(730.3)
283/4 (730.3)
209/16
(522.3)
K _
149/16 (369.9) 16(406.4)
183/16 (462) 16(406.4)
2113/16(554) 16(406.4)
161/16
149/16 (369.9) (408)
183/16 (462) 161/16
(4o8)
161/16
2113/16(554) (408)
Opening In Floor
161/4
(412.8)
161/4
(412.8)
161/4
(412.8)
161/4
(412.8)
N
145/8
(371.5)
181/4
(463.6)
21//8
(555.6)
145/8
(371.5)
181/4
(463.6)
21//8
(555.6)
Opening In
Base For Plenum
15 (381)
15 (381)
15 (381)
R
131/2
(342.9)
171/8
(435.6)
19_/4
(501.7)
131/2
(342.9)
171/8
(435.6)
19_/4
(501.7)
Typical Plenum
Dimensions
S T
15 (381)
15 (381)
15 (381)
15 (381)
15 (381)
15 (381)
209/16
(522.3)
209/16
(522.3)
161/4
(412.8)
161/4
(412.8)
15 (381)
15 (381)
15 (381)
131/2
(342.9)
171/8
(435.6)
19_/4
(501.7)
131/2
(342.9)
171/8
(435.6)
19_/4
(501.7)
Outside Dimension
** BaseSpacer SideTo Side
i ii
Exploded View of Sub-Base for
: ; r_i_u_'=°; Furnace ONLY
iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
z" _<3_r_ _ s A = 4 1/4" (108mm) Minimum
_1 .... _" clearance from back of hole
S_ Plenum _: to wall or other obstruction.
H_ _ 2" (50.8mm)
2" (50.8mm)__'_ 1" (25.4mm)
Sub-base for Combustible Floors- Downflow Coil
Adapter Box
The sub-base for combustible floors is not required when a down-
flow furnace, used with a downflow coil box, is set on combus-
tible flooring.
1. Cut the opening in the floor according to the dimensions in
Table 7 because the base is equipped with locating tabs
that center the base over the opening.
The opening in the base is 11/4" (31.8mm) shorter and 11/8"
(28.6mm) narrower than the minimum required size of the
opening in the floor. This is done to maintain a 1" (25.4mm)
clearance between the floor and the plenum.
44101 202301
Specifications are subject to change without notice
28