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441 01 3700 00
Specifications are subject to change without notice.
10
INSTALLATION
UPFLOW INSTALLATION
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 2 screws holding bottom
filler panel. (See Fig. 9.)
2. Rotate bottom filler panel downward to release holding
tabs.
3. Remove bottom closure panel.
4. Reinstall bottom filler panel and screws.
Side Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return--air opening. This panel MUST be in place when
only side return air is used.
Bottom
Closure Panel
Bottom Filler Panel
A10273
Fig. 9 -- Removing Bottom Closure Panel
NOTE
: Side return--air openings can be used in UPFLOW and
most HORIZONTAL configurations. Do not use side return--air
openings in DOWNFLOW configuration.
Leveling Legs (If Desired)
In upflow position with side return inlet(s), leveling legs may be
used. (See Fig. 10.) Install field--supplied, 5/16 X 1--1/2 in. (8 X
38 mm) (max) corrosion--resistant machine bolts, washers and
nuts.
1
3
/
4
1
3
/
4
1
3/
4
1
3/
4
5/
16
5
/
16
5/
16
5/
16
(44mm)
(8mm)
(44mm)
(8mm)
(8mm)
(8mm)
(44mm)
(44mm)
A89014
Fig. 10 -- Leveling Legs
NOTE
: Bottom closure must be used when leveling legs are
used. It may be necessary to remove and reinstall bottom closure
panel to install leveling legs. To remove bottom closure panel, see
Item 1 in Bottom Return Air Inlet section in Step 1 above.
To install leveling legs:
1. Position furnace on its back. Locate and drill a hole in
each bottom corner of furnace. (See Fig. 10.)
2. For each leg, install nut on bolt and then install bolt with
nut in hole. (Install flat washer if desired.)
3. Install another nut on other side of furnace base. (Install
flat washer if desired.)
4. Adjust outside nut to provide desired height, and tighten
inside nut to secure arrangement.
5. Reinstall bottom closure panel if removed.
DOWNFLOW INSTALLATION
NOTE
: For downflow applications, this furnace is approved for
use on combustible flooring when any one of the following 3
accessories are used:
S
Downflow combustible floor subbase
S
Cased Coil numbers END4X, ENW4X
S
Coil casing model number NAEA
1. Determine application being installed from Table 3.
2. Construct hole in floor per Table 3 and Fig. 11.
3. Construct plenum to dimensions specified in Table 3 and
Fig. 11.
4. If downflow subbase is used, install as shown in Fig. 12. If
Coil model number END4X, ENW4X or Coil Casing
model number NAEA is used, install as shown in Fig. 13.
NOTE
: It is recommended that the perforated supply--air duct
flanges be completely folded over or removed from furnace when
installing the furnace on a factory--supplied cased coil or coil box.
To remove the supply--air duct flange, use wide duct pliers or
hand seamers to bend flange back and forth until it breaks off. Be
careful of sharp edges. (See Fig. 14.)
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 2 screws holding bottom
filler panel. (See Fig. 9.)
2. Rotate bottom filler panel downward to release holding
tabs.
3. Remove bottom closure panel.
4. Reinstall bottom filler panel and screws.
HORIZONTAL INSTALLATION
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.
!
WARNING
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.