Use Of Furnace As A Construction Heater; General - Lennox SL280UHNV Installation Instructions Manual

Installed in Combination with a Cooling Coil
When this furnace is used with cooling units, it shall be in-
stalled in parallel with, or on the upstream side of, cooling
units to avoid condensation in the heating compartment.
See Figure 2. With a parallel flow arrangement, a damper
(or other means to control the flow of air) must adequately
prevent chilled air from entering the furnace. If the damper
is manually operated, it must be equipped to prevent op-
eration of either the heating or the cooling unit, unless it is
in the full HEAT or COOL setting.
Heating Unit Installed Parallell to Air Handler Unit
(open during heating operation only)
Air Handler Unit
(open during cooling operation only)
Heating Unit Installed Upstream of Cooling Unit
Evaporator
FIgURE 2
When installed, this furnace must be electrically grounded
according to local codes. In addition, in the United States,
installation must conform with the current National Elec-
tric Code, ANSI/NFPA No. 70. The National Electric Code
(ANSI/NFPA No. 70) is available from the following ad-
dress:
National Fire Protection Association
1 Battery March Park
Quincy, MA 02269
NOTE - This furnace is designed for a minimum contin-
uous return air temperature of 60°F (16°C) or an inter-
mittent operation down to 55°F (13°C) dry bulb for cases
where a night setback thermostat is used. Return air tem-
perature must not exceed 85°F (29°C) dry bulb.
Dampers
Gas Unit
Dampers
Gas Unit
The SL280UHNV furnace may be installed in alcoves,
closets, attics, basements, garages, and utility rooms in
the upflow or horizontal position.
This furnace is not designed for installation in mobile
homes, recreational vehicles, or outdoors.
Never use an open flame to test for gas leaks. Check all
connections using a commercially available soap solution
made specifically for leak detection.
Use of Furnace as Construction Heater
Construction heat is not allowed with this furnace.

general

These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
having jurisdiction before installation.
In addition to the requirements outlined previously, the
following general recommendations must be considered
when installing a SL280UHV furnace:
• Place the furnace as close to the center of the air distri-
bution system as possible. The furnace should also be
located close to the chimney or vent termination point.
• Do not install the furnace where drafts might blow di-
rectly into it. This could cause improper combustion and
unsafe operation.
• Do not block the furnace combustion air openings with
clothing, boxes, doors, etc. Air is needed for proper
combustion and safe unit operation.
• When the furnace is installed in an attic or other insulat-
ed space, keep insulation away from the furnace.
• Please consult the manufacturer of your evaporator
coil for their recommendations on distance required
between the heat exchanger and their drain pan. Ad-
equate space must be provided between the drain pan
and the furnace heat exchanger.
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