Sears PG8MAA Installation, Start-Up And Service Instructions Manual page 11

NOTE: Side return-air openings can be used in UPFLOW and
most HORIZONTAL configurations. Do not use side return-air
openings in DOWNFLOW configuration.
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 ram) (max) corrosion-resistant machine bolts, washers and
nuts.
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.
(8mm)
I 3/4'
(44mm)
(8mm)
5/16"
(44mm) 1 3/4"
(44mm)
I
3/4'_"_
1
3/4"
(44mm)
(8mm)
A89014
Fig. 10 - Leveling Legs
Leveling Legs (If Desired)
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 and
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:
• Special Base, KGASB
• Cased Coil Assembly Part No. CNPV, CNRV, CAR,
or CAP
• Coil Box Part No. KCAKC
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 4 and
Fig. 11.
4. If downflow subbase, KGASB is used, install as shown in
Fig. 12. If Coil Assembly Part No. CNPV, CNRV, CAR,
or CAP or Coil Box Part No. KCAKC is used, install as
shown in Fig. 13.
A96283
Fig. 11 - Floor and Plenum Opening Dimensions
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. 140
FURNACE
(OR COIL CASING
WHEN USED)
COMBUSTIBLE
FLOORING \
SUBBASE
SHEET METAL
PLENUM
FLOOR
OPENING
A96285
Fig. 12 - Furnace, Plenum, and Subbase Installed on a
Combustible Floor
11