Use Of Furnace As A Construction Heaterl; General - Lennox DAVE SIGNATURE SL297UHNV Installation Instructions Manual

Installed in Combination with a Cooling Coil
When this furnace is used with cooling coils (figure 3), it
shall be installed in parallel with, or on the upstream side
of, cooling coils to avoid condensation in the heating com-
partment. 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.
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
In Canada, all electrical wiring and grounding for the unit
must be installed according to the current regulations of
the Canadian Electrical Code Part I (CSA Standard C22.1)
and/or local codes.
Heating Unit Installed Parallel to Air Handler Unit
(open during heating operation only)
AIR FLOW
Air Handler Unit
(open during cooling operation only)
Heating Unit Installed Upstream of Cooling Coil
AIR FLOW
Cooling Coil
FIGURE 3
NOTE - This furnace is designed for a minimum continu-
ous return air temperature of 60°F (16°C) or an intermittent
operation down to 55°F (13°C) dry bulb for cases where a
night setback thermostat is used. Return air temperature
must not exceed 85°F (29°C) dry bulb.
The SL297UHNV furnace may be installed in alcoves,
closets, attics, basements, garages, crawl spaces and
utility rooms in the upflow or horizontal position.
This furnace design has not been CSA certified for instal-
lation in mobile homes, recreational vehicles, or outdoors.
Dampers
Gas Unit
AIR FLOW
Dampers
Gas Unit
AIR FLOW
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 SL297UHNV furnace:
• Place the furnace as close to the center of the air
distribution system as possible. The furnace should
also be located close to the vent termination point.
• When the furnace is installed in an attic or other
insulated space, keep insulation away from the fur-
nace.
• When the furnace is installed in an unconditioned
space, consider provisions required to prevent
freezing of condensate drain system.
• Please consult the manufacturer of your evaporator
coil for their recommendations on distance required
between the heat exchanger and their drain pan.
Adequate space must be provided between the
drain pan and the furnace heat exchanger.
SL297UHNV unit should not be installed in areas
normally subject to freezing temperatures.
Shipping Bolt Removal
Units with 1/2 hp blower motor are equipped with three
flexible legs and one rigid leg. The rigid leg is equipped
with a shipping bolt and a flat white plastic washer (rather
than the rubber mounting grommet used with a flexible
mounting leg). See figure 4. The bolt and washer must
be removed before the furnace is placed into opera-
tion. After the bolt and washer have been removed, the
rigid leg will
Page 5
CAUTION
not touch the blower
UNITS WITH 1/2 HP
BLOWER MOTOR
RIGID LEG
remove shipping bolt and washer
FIGURE 4
housing.