Bryant 312A Installation, Start-Up, Operating And Service And Maintenance Instructions page 12

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. piece of sheet metal for
flame roll- -out protection in front of burner area for furnaces
closer than 12 inches above the combustible deck or suspended
furnaces closer than 12 inches to joists. The sheet metal MUST
extend underneath the furnace casing by 1 in. with the door
removed.
The bottom closure panel on furnaces of widths 17- -1/2 in. and
larger may be used for flame roll- -out protection when bottom of
furnace is used for return air connection. See Fig. 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 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
side return air inlet(s) are used without a bottom return air inlet.
A
PLENUM
OPENING
B
OPENING
C
Fig. 11 - - Floor and Plenum Opening Dimensions
D
FLOOR
A096283
FURNACE
(OR COIL CASING
WHEN USED)
COMBUSTIBLE
FLOORING
DOWNFLOW
SUBBASE
SHEET METAL
PLENUM
FLOOR
OPENING
Fig. 12 - - Furnace, Plenum, and Subbase installed on a
Combustible Floor
FURNACE
CD5 OR CK5
COIL ASSEMBLY
OR KCAKC
COIL BOX
COMBUSTIBLE
FLOORING
SHEET METAL
PLENUM
FLOOR
OPENING
Fig. 13 - - Furnace, Plenum, and Coil Assembly or Coil Box
Installed on a Combustible Floor
12
A096285
A04140
A04140