SYSTEM OPERATION
9
cabinets.
• Hot or cold air from registers.
• Radiant heat from the sun.
• Light fixtures or other appliances.
• Radiant heat from a fireplace.
• Concealed hot or cold water pipes, or chimneys.
• Unconditioned areas behind the thermostat, such as an
outside wall.
Consult the instructions packaged with the thermostat for
mounting instructions and further precautions.
Combustion & Ventilation Air Requirements
Improved construction and additional insulation in buildings have
reduced heat loss by reducing air infiltration and escape around
doors and windows. These changes have helped in reducing
heating/cooling costs but have created a problem supplying
combustion and ventilation air for gas fired and other fuel burning
appliances. Appliances that pull air out of the house (clothes
dryers, exhaust fans, fireplaces, etc.) increase the problem by
starving appliances for air.
House depressurization can cause back drafting or improper
combustion of gas-fired appliances, thereby exposing building
occupants to gas combustion products that could include carbon
monoxide.
If this furnace is to be installed in the same space with other
gas appliances, such as a water heater, ensure there is an
adequate supply of combustion and ventilation air for the other
appliances. Refer to the latest edition of the National Fuel
Gas Code NFPA 54/ANSI Z223.1 or CAN/CSA B149.1-15
Installation Codes or applicable provisions of the local building
codes for determining the combustion air requirements for
the appliances.
Most homes will require outside air be supplied to the furnace
area by means of ventilation grilles or ducts connecting
directly to the outdoors or spaces open to the outdoors such
as attics or crawl spaces.
Installation Positions
This furnace may be installed in an upright position or horizontal
on either the left or right side panel. Do not install this furnace
on its back. For
upright upflow
furnaces, return air ductwork
may be attached to the side panel(s) and/or basepan. For
horizontal upflow
furnaces, return air ductwork must be
attached to the basepan. For both
upright or horizontal
counterflow
furnaces, return ductwork must be attached to
the basepan (top end of the blower compartment).
NOTE:
Ductwork must never be attached to the back of the furnace.
Contact your distributor for proper airflow requirements
and number of required ductwork connections. Refer to
“Recommended Installation Positions” figure for appropriate
installation positions, ductwork connections, and resulting
airflow arrangements.
Horizontal Applications & Considerations
TILT OUTWARD TOALLOWFOR
DOOR AND CIRCULATOR BLOWER
REMOVAL
DIAMETER
THREADED ROD
PLACES
3/8"
(6
)
PROVIDE
MINMUM CLEARANCE BETWEEN
CENTER ROD AND FURNACE CABINET
TO ALLOW FOR CIRCULATOR BLOWER REMOVAL
8"
ASSURE FURNACE IS LEVEL FROM
END TO END AND HAS A SLIGHT
FORWARD TILT WITH THE FRONT
OF THE FURNACE
BELOW THE BACK OF THE FURNACE
0"-3/4"
POSITION AS CLOSE AS POSSIBLE
TO BLOWER DECK TO ALLOW FOR
CIRCULATOR BLOWER REMOVAL
ANGLE IRON
PLACES
2" 2" 3/8"
(3
)
X X
HOLD DOWN
NUTS
SUPPORT
NUTS
Figure 2
When installing a furnace horizontally, additional consideration
must be given to the following:
Furnace Suspension
If suspending the furnace from rafters or joists, use 3/8” threaded
rod and 2”x2”x1/8” angle iron as shown in the following diagram.
The length of rod will depend on the application and the clearances
necessary.
If the furnace is installed in a crawl space it must be
suspended from the floor joist or supported by a concrete
pad. Never install the furnace on the ground or allow it to be
exposed to water.
Front Cover Pressure Switch Tube Location
When a furnace is installed horizontally with left
side down the front cover pressure switch tube
must be re-located to the lower port of the collec
-
tor box cover.
1. Remove tube from front cover pressure switch and
collector box cover.
2. Remove rubber plug from bottom collector box port and
install on top collector box port.
3. Locate 24” x 1/4” tube in bag assembly.
4. Install one end on front cover pressure switch.
5. Route tube to lower port on collector box cover and cut
off excess tubing.
Drain Trap and Lines
In horizontal applications the condensate drain trap is secured
to the furnace side panel, suspending it below the furnace. A
minimum clearance of 5 ½” below the furnace must be provided
for the drain trap. Additionally, the appropriate downward
piping slope must be maintained from the drain trap to the
drain location. Refer to
Condensate Drain Trap and Lines
for
further details. If the drain trap and drain line will be exposed
to temperatures near or below freezing, adequate measures
must be taken to prevent condensate from freezing.
