Opening Dimensions; Suspended Furnace Support; Air Inlet - International comfort products R8MXL Installation Instructions Manual

FURNACE
CASING
WIDTH
Upflow Applications on Combustible or Noncombustible Flooring
Downflow Applications on Noncombustible Flooring
14–3/16
(360)
Downflow Applications on Combustible Flooring (subbase required)
Downflow Applications on Combustible Flooring with Coil END4X,
ENW4X or Coil Casing NAEA (subbase not required)
Upflow Applications on Combustible or Noncombustible Flooring
Downflow Applications on Noncombustible Flooring
17–1/2
(445)
Downflow Applications on Combustible Flooring (subbase required)
Downflow Applications on Combustible Flooring Coil with Coil
END4X, ENW4X or Coil Casing NAEA (subbase not required)
Upflow Applications on Combustible or Noncombustible Flooring
Downflow Applications on Noncombustible Flooring
21
(533)
Downflow Applications on Combustible Flooring (subbase required)
Downflow Applications on Combustible Flooring with Coil END4X,
ENW4X or Coil Casing NAEA (subbase not required)
Upflow Applications on Combustible or Noncombustible Flooring
Downflow Applications on Noncombustible Flooring
24−1/2
(622)
Downflow Applications on Combustible Flooring (subbase required)
Downflow Applications on Combustible Flooring with Coil END4X,
ENW4X or Coil Casing NAEA (subbase not required)
HORIZONTAL INSTALLATION
WARNING
!
FIRE, EXPLOSION, AND CARBON MONOXIDE
POISONING HAZARD
Failure to follow this warning could result in personal
injury, death, and/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.
The furnace can be installed horizontally in an attic or crawl
space 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.

Suspended Furnace Support

The furnace may be supported under each end with threaded
rod, angle iron or metal plumber's strap as shown. (See
Figure 15 and Figure 16) Secure angle iron to bottom of
furnace as shown. Heavy−gauge sheet metal straps
(plumber's straps) may be used to suspend the furnace from
each bottom corner. To prevent screws from pulling out, use 2
#8 x 3/4−in. (19 mm) screws into the side and 2 #8 x 3/4−in.
(19 mm) screws in the bottom of the furnace casing for each
strap. (See Figure 15 and Figure 16) If the screws are
attached to ONLY the furnace sides and not the bottom, the
straps must be vertical against the furnace sides and not pull
away from the furnace sides, so that the strap attachment
12
Table 4 – Opening Dimensions − In. (mm)
APPLICATION
(subbase not required)
(subbase not required)
(subbase not required)
(subbase not required)
(subbase not required)
(subbase not required)
(subbase not required)
(subbase not required)
Specifications are subject to change without notice.
PLENUM OPENING
A
12−11/16 21−5/8
(322) (549)
12−9/16
(319) (483)
11−13/16
(284) (483)
12−5/16
(313) (483)
16 21−5/8
(406) (549)
15−7/8
(403) (483)
15−1/8
(384) (483)
15−1/2
(394) (483)
19−1/2 21−5/8
(495) (549)
19−3/8
(492) (483)
18−5/8
(473) (483)
19
(483) (483)
23 21−1/8
(584) (537)
22−7/8
(581) (483)
22−1/8
(562) (483)
22−1/2
(572) (483)
screws are not in tension (are loaded in shear) for reliable
support.
Platform Furnace Support
Construct working platform at location where all required
furnace clearances are met. (See Figure 2 and Figure 17) For
furnaces with 1−in. (25 mm) clearance requirement on side,
set furnace on noncombustible blocks, bricks or angle iron.
For crawl space installations, if the furnace is not suspended
from the floor joists, the ground underneath furnace must be
level and the furnace set on blocks or bricks.
Roll−Out Protection
Provide a minimum 17−3/4 in. x 22 in. (451 mm x 559 mm)
piece of sheet metal for flame roll−out protection in front of
burner area for furnaces closer than 12 inches (305 mm)
above the combustible deck or suspended furnaces closer
than 12 inches (305 mm) to joists. The sheet metal MUST
extend underneath the furnace casing by 1 in. (25 mm) with
the door removed.
The bottom closure panel on furnaces of widths 17−1/2 in.
(445 mm) and larger may be used for flame roll−out
protection when bottom of furnace is used for return air
connection. See Figure 17 for proper orientation of roll−out
shield.
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel
installed in bottom return−air opening. Remove and discard
this panel when bottom return air is used. To remove bottom
closure panel, perform the following:
1. Tilt or raise furnace and remove two screws holding
bottom filler panel. (See Figure 9)
FLOOR OPENING
B C D
13−5/16 22−1/4
(338) (565)
19 13−3/16 19−5/8
(335) (498)
19 13−7/16 20−5/8
(341) (600)
19 13−5/16 20
(338) (508)
16−5/8 22−1/4
(422) (565)
19 16−1/2 19−5/8
(419) (498)
19 16−3/4 20−5/8
(425) (600)
19 16−1/2 20
(419) (508)
20−1/8 22−1/4
(511) (565)
19 20 19−5/8
(508) (498)
19 20−1/4 20−5/8
(514) (600)
19 20 20
(508) (508)
23−5/8 22−1/4
(600) (565)
19 23−1/2 19−5/8
(597) (498)
19 23−3/4 20−5/8
(603) (600)
19 23−1/2 20
(597) (508)
441 01 6100 01