INSTALLATION INSTRUCTIONS
Gas Furnace: (F/G)9MAE
20
440 01 4300 02
Specifications subject to change without notice.
Table 5
Opening Dimensions
−
in. (mm)
FURNACE
CASING WIDTH
IN. (mm)
APPLICATION
PLENUM OPENING
FLOOR OPENING
A
B
C
D
17–1/2
(445)
Upflow Applications on Combustible or Noncombustible Flooring
(subbase not required)
16
(406)
21
−
5/8
(549)
16
−
5/8
(422)
22
−
1/4
(565)
Downflow Applications on Noncombustible Flooring
(subbase not required)
15
−
7/8
(403)
19
(483)
16
−
1/2
(419)
19
−
5/8
(498)
Downflow applications on combustible flooring (subbase required)
15
−
1/8
(384)
19
(483)
16
−
3/4
(425)
20
−
5/8
(600)
Downflow Applications on Combustible Flooring with Coil Assembly or coil
box (subbase not required)
15
−
1/2
(394)
19
(483)
16
−
1/2
(419)
20
(508)
21
(533)
Upflow Applications on Combustible or Noncombustible Flooring
(subbase not required)
19
−
1/2
(495)
21
−
5/8
(549)
20
−
1/8
(511)
22
−
1/4
(565)
Downflow Applications on Noncombustible Flooring
(subbase not required)
19
−
3/8
(492)
19
(483)
20
(508)
19
−
5/8
(498)
Downflow applications on combustible flooring
(subbase required)
18
−
5/8
(473)
19
(483)
20
−
1/4
(514)
20
−
5/8
(600)
Downflow Applications on Combustible Flooring with Coil Assembly or coil
box (subbase not required)
19
(483)
19
(483)
20
(508)
20
(508)
24
−
1/2
(622)
Upflow Applications on Combustible or Noncombustible Flooring
(subbase not required)
23
(584)
21
−
1/8
(537)
23
−
5/8
(600)
22
−
1/4
(565)
Downflow Applications on Noncombustible Flooring
(subbase not required)
22
−
7/8
(581)
19
(483)
23
−
1/2
(597)
19
−
5/8
(498)
Downflow applications on Combustible flooring
(subbase required)
22
−
1/8
(562)
19
(483)
23
−
3/4
(603)
20
−
5/8
(600)
Downflow Applications on Combustible Flooring with Coil Assembly or
coil box (subbase not required)
22
−
1/2
(572)
19
(483)
23
−
1/2
(597)
20
(508)
Figure 22
Furnace, Plenum, and Subbase
Installed on a Combustible Floor
A96285
HORIZONTAL INSTALLATION
NOTE
: The furnace must be pitched forward as shown in
Figure 17
for proper condensate drainage.
!
WARNING
FIRE, EXPLOSION, AND CARBON MONOXIDE POISONING
HAZARD
Failure to follow this warning could result in personal injury, death, or
property damage.
Do not install the furnace on its back or hang furnace with control
compartment facing downward. Safety control operation will be
adversely affected. Never connect return
−
air ducts to the back of the
furnace.
!
CAUTION
MINOR PROPERTY HAZARD
Failure to follow this caution may result in minor property damage.
Local codes may require a drain pan under entire furnace and
condensate trap when a condensing furnace is used in an attic
application or over a finished ceiling.
The furnace can be installed horizontally in an attic or
crawlspace on either the left
−
hand (LH) or right
−
hand (RH)
side. The furnace can be hung from floor joists, rafters or
trusses or installed on a non
−
combustible platform, blocks,
bricks or pad.