Use Of Furnace As Construction Heater - Lennox EL296UHE Installation Instructions Manual

In order to ensure proper unit operation in non-direct vent
applications, combustion and ventilation air supply must be
provided according to the current National Fuel Gas Code
or CSA‐B149 standard.
Installation Locations
This furnace is CSA International certified for installation
clearances to combustible material as listed on the unit
nameplate and in the table in figure 12. Accessibility and
service clearances must take precedence over fire protec­
tion clearances.
NOTE - For installation on combustible floors, the furnace
shall not be installed directly on carpeting, tile, or other
combustible material other than wood flooring.
For installation in a residential garage, the furnace must be
installed so that the burner(s) and the ignition source are
located no less than 18 inches (457 mm) above the floor.
The furnace must be located or protected to avoid physical
damage by vehicles. When a furnace is installed in a public
garage, hangar, or other building that has a hazardous at­
mosphere, the furnace must be installed according to rec­
ommended good practice requirements and current Na­
tional Fuel Gas Code or CSA B149 standards.
NOTE - Furnace must be adjusted to obtain a temperature
rise within the range specified on the unit nameplate. Fail­
ure to do so may cause erratic limit operation and prema­
ture heat exchanger failure.
This EL296UHE furnace must be installed so that its
electrical components are protected from water.
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 compart­
ment. 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 manu­
ally operated, it must be equipped to prevent operation 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 Electric
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
(open during cooling operation only)
Heating Unit Installed Upstream of Cooling Coil
AIR FLOW
Cooling Coil
NOTE - This furnace is designed for a minimum continuous
return air temperature of 60°F (16°C) or an intermittent op­
eration 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 EL296UHE furnace may be installed in alcoves, clos­
ets, attics, basements, garages, crawl spaces and utility
rooms in the upflow or horizontal position.
This furnace design has not been CSA certified for installa­
tion in mobile homes, recreational vehicles, or outdoors.

Use of Furnace as Construction Heater

Lennox does not recommend the use of EL296UHE units
as a construction heater during any phase of construction.
Very low return air temperatures, harmful vapors and op­
eration of the unit with clogged or misplaced filters will dam­
age the unit.
EL296UHE units may be used for heating of buildings or
structures under construction, if the following conditions
are met:
The vent system must be permanently installed per
D
these installation instructions.
A room thermostat must control the furnace. The use of
D
fixed jumpers that will provide continuous heating is not
allowed.
The return air duct must be provided and sealed to the
D
furnace.
Return air temperature range between 60°F (16°C) and
D
80°F (27°C) must be maintained.
Air filters must be installed in the system and must be
D
maintained during construction.
D Air filters must be replaced upon construction comple­
tion.
Page 4
Dampers
Gas Unit
AIR FLOW
Air Handler Unit
Dampers
Gas Unit
AIR FLOW
FIGURE 3