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UNIT DAMAGE HAZARD
This gas furnace may be used for construction heat provided
that:
-The furnace is permanently installed with all electrical
wiring, piping, air filters, venting and ducting installed
according to these installation instructions. A return air duct
is provided, sealed to the furnace casing, and terminated
outside the space containing the furnace. This prevents a
negative pressure condition as created by the circulating air
blower, causing a flame rollout and/or drawing combustion
products into the structure.
-The furnace is controlled by a thermostat. It may not be
″
hot
wired
″
to provide heat continuously to the structure without
thermostatic control.
-Clean outside air is provided for combustion. This is to
minimize the corrosive effects of adhesives, sealers and other
construction materials. It also prevents the entrainment of
drywall dust into combustion air, which can cause fouling and
plugging of furnace components.
-The temperature of the return air to the furnace is maintained
between 55°F (13°C) and 80°F (27°C), with no evening
setback or shutdown. The use of the furnace while the
structure is under construction is deemed to be intermittent
operation per our installation instructions.
-The air temperature rise is within the rated rise range on the
furnace rating plate, and the firing rate has been set to the
nameplate value.
-The filters used to clean the circulating air during the
construction process must be either changed or thoroughly
cleaned prior to occupancy.
-The furnace, ductwork and filters are cleaned as necessary to
remove drywall dust and construction debris from all HVAC
system components after construction is completed.
-After construction is complete, verify furnace operating
conditions including ignition, input rate, temperature rise and
venting, according to the manufacturer’s instructions.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in minor property or
unit damage.
If this furnace is installed in an unconditioned space where
the ambient temperatures may be 32°F or lower, freeze
protection measures must be taken. (See Fig. 16.)
Step 2—Furnace Location Relative to Cooling
Equipment
The cooling coil must be installed parallel with or on downstream
side of furnace to avoid condensation in heat exchanger. When
installed parallel with a furnace, dampers or other means used to
control flow of air shall be adequate to prevent chilled air from
entering furnace. If dampers are manually operated, they must be
equipped with a means to prevent operation of either unit unless
the damper is in full-heat or full-cool position.
Step 3—Hazardous Locations
FIRE, EXPLOSION, INJURY OR DEATH HAZARD
Improper location or inadequate protection could result in fire
or explosion.
When the furnace is installed in a residential garage, the
burners and ignition sources must be located at least 18 in.
above the floor. The furnace must be located or protected to
avoid physical damage by vehicles. When the furnace is
installed in a public garage, airplane hangar, or other building
having a hazardous atmosphere, the furnace must be installed
in accordance with the NFGC or NSCNGPIC. (See Fig. 17.)
Step 4—Furnace Location and Application
DIRECT VENT (2-PIPE) APPLICATION
Furnace may be located in a confined space without special
provisions for dilution or ventilation air.
Fig. 14—Proper Condensate Drainage
A02146
UPFLOW OR DOWNFLOW
HORIZONTAL
FRONT
LEVEL (0
″
)
TO
1
⁄
2
″
MAX
MIN
1
⁄
4
″
TO
1
⁄
2
″
MAX
FRONT
Fig. 15—Prohibit Installation on Back
A93043
FRONT
BACK
FRONT
B
A
C
K
Fig. 16—Freeze Protection
A93058
32
°
F MINIMUM INSTALLED
AMBIENT OR FREEZE
PROTECTION REQUIRED
15
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