650.75-N4U
035-14370-000
12
Unitary Products Group
This appliance is design certified for line contact for furnaces
installed horizontally. The intersection of the furnace top and
sides form a line. This line may be in contact with combustible
material. Refer to “Where it will not interfere with the cleaning,
servicing or removal of other appliances." Section on page 5
in this manual for additional information.
Secure a platform constructed of plywood or other building
material to the floor joists. Sheet metal, 12" in front of the fur-
nace combustion air openings is recommended. (Refer to
Figure 9.)
Note: The unit must be elevated to allow clearnace fo the
condensate trap and drain pipe. .
NOTE:See crawl space installation for suspending the fur-
nace in attic installations.
CRAWL SPACE INSTALLATION
The furnace can be hung from floor hoists or installed on suit-
able blocks or pad. Blocks or pad installations shall provide
adequate height to ensure the unit will not be subject to water
damage.
When suspending the furnace from rafters or floor joists
using rod, pipe or straps, refer to Physical Data and,Table 3,
“UNIT CLEARANCES TO COMBUSTIBLES,” on page 8, for
furnace weights to determine suitable means of suspension.
Angle supports should be placed at the supply aire end and
near the blower deck. (Refer to Figure 9.) Do not support
at return air end of unit.
Units may also be suspended by using straps or other mate-
rial at the same location. All four suspension points must be
level to ensure quiet furnace operation.
GAS PIPING
The gas supply must be installed in accordance with the cur-
rent National Fuel Gas Code, ANSI Z223.1 (in the U.S.) or
CAN-B149.1 or.2 (in Canada) installation codes and all appli-
cable local and utility requirements. All pipe and fitting mate-
rial, pipe size and installation procedures must comply with
the appropriate code. Some utilities may require larger pipe
sizes than shown in the code. Gas piping may be connected
from either side of the furnace. Each side of the unit has two
gas pipe entry knockouts.
For downflow/horizontal models,
plan your combustion air
piping before determining the correct gas pipe entry. Use 90
degree service elbow(s), or short nipples and conventional 90
degree elbow(s) to enter through the cabinet access holes..
If this furnace is installed over a finished space, a
condensate safety pan must be installed.
When a furnace is installed in an attic or other
insulated space, keep all insulating materials at
least 12" away from furnace and burner combus-
tion air openings.
FIGURE 9 : TYPICAL FURNACE INSTALLATION
USING SUSPENSION MATERIALS
SUPPORT
ROD
ANGLE IRON
BRACKET
6" MIN BETWEEN
ROD & FURNACE
1" MAX BETWEEN
ROD & FURNACE
1" MAX BETWEEN
ROD & FURNACE
In any application where temperatures below
freezing are possible, See “BELOW FREEZING
LOCATIONS” on page 5
An overpressure protection device, such as a
pressure regulator, which conforms to the National
Fuel Gas Code, ANSI Z223.1 (U.S.) or CAN-
B149.1 or.2 (Canada) and acts to limit the down-
stream pressure to a value that does not exceed
0.5 PSI (14" w.c.), must be installed in the gas pip-
ing system upstream of the furnace. Failure to do
so may result in a fire or explosion or cause dam-
age to the furnace or some of its components.
