SettinganUpflowUnit
Whenthesidereturnairinletsareusedinanupflowap-
plication,itmaybenecessarytoinstallshimsonthebottom
ofthefurnace.Ifdesired,usefield-suppliedcorrosion-re-
sistant5/16inchmachinebolts(4)andnuts(8)tolevelthe
furnace,Seefigure8,
NOTE - The maximum length of the bolt is 1-1/2 inches.
1 - Lay the furnace on its back and drill a 5/16 inch diame-
ter hole in each corner of the furnace's bottom, See fig-
ure 8 for the correct location of the holes, Drill through
the bottom panel and the bottom flange of the cabinet.
2 - Install one bolt and two nuts into each hole. Screw the
first nut onto a bolt and then insert the bolt into a hole. A
flat washer may be added between the nut and the bot-
tom of the unit.
3 - Screw another nut onto the bolt on the inside of the fur-
nace base. A flat washer may be added between the
nut and the bottom of the unit,
4 - Adjust the outside nut to the appropriate height and
tighten the inside nut to secure the arrangement,
Leveling Bolt Installation
Inches (mm)
3/8
Furnace Front _ยข
3/8 1-3/4
(44)
1-3/4
(44)
Leveling Bolt
Locati,
Furnace
Bottom
Leveling Bolt
Locations
3/8
(10)
3/8 1-3/4
(10) (44)
I-3/4 (44)
FIGURE 8
Downflow Applications
The unit may be installed three ways in downflow applica-
tions: on non-combustible flooring, on combustible flooring
using an additive base, or on a reverse-flow cooling coil
cabinet. Do not drag the unit across the floor in the
downflow position. Flange damage will result.
Refer to figure 9 for clearances in downflow applica-
tions.
Downflow Application Installation Clearances
Top
LeftSide _ Right Side
Boffom
Top 0
*Front 0
Back 0
Sides 0t
Vent 0
Floor NC$
*Front clearance in alcove installation must be 24 in. (610 ram).
Maintain a minimum of 24 in. (610 ram) for front service access.
tAllow proper clearances to accommodate condensate trap and
vent pipe installation.
SThe furnace may be installed on a combustible wood floor if an
optional additive base is installed between the furnace and the
combustible floor.
FIGURE 9
Installation on Non-Combustible Flooring
1 - Cut floor opening keeping in mind clearances listed on
unit rating plate. Also keep in mind gas supply connec-
tions, electrical supply, flue and air intake connections
and sufficient installation and servicing clearances,
See table 1 for correct floor opening size.
2 - Flange warm air plenum and lower the plenum into the
opening.
3 - Set the unit over the plenum and seal the plenum to
the unit,
4 - Ensure that the seal is adequate,
TABLE 1
NON-COMBUSTIBLE FLOOR
Front to Rear
Model No.
mm
B Cabinet (17.5") 502
CCabinet(21") 502
DCabinet(24.5") 502
in.
19 - 3/4
19 - 3/4
19 - 3/4
)PENING SIZE
Side to Side
in. mm
16 - 5/8 422
20-1/8 511
23 - 5/8 600
NOTE - Floor opening dimensions listed are 1/4 inch (6 mm) larger than
the unit opening. See dimension drawing on page 2.
Page 9