Use Of Furnace As Construction Heater - Lennox G71MPP Installation Instructions Manual

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 haz-
ardous atmosphere, the furnace must be installed accord-
ing to recommended good practice requirements and cur-
rent National Fuel Gas Code or CSA B149 standard.
NOTE − Furnace must be adjusted to obtain a temperature
rise within the range specified on the unit nameplate. Failure
to do so may cause erratic limit operation.
This G71MPP furnace may be used as a high−static unit
heater. The G71MPP may also be installed in an aircraft
hangar in accordance with the Standard for Aircraft Han-
gars (ANSI/NFPA No. 408−1990).
Installation in parking structures must be in accordance
with the Standard for Parking Structures (ANSI/NFPA No.
88A−1991). Installation in repair garages must be in accor-
dance with the Standard for Repair Garages (ANSI/NFPA
No. 88B−1991).
This G71MPP furnace must be installed so that its electri-
cal components are protected from water.
When this furnace is used with cooling units, it shall be
installed in parallel with, or on the upstream side of, cooling
units to avoid condensation in the heating compartment.
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 oper-
ated, 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.
Do not set thermostat below 60°F (16°C) in heating
mode. Setting thermostat below 60°F (16°C) reduces
the number of heating cycles. Damage to the unit
may occur that is not covered by the warranty.
The G71MPP furnace may be installed in alcoves, closets,
attics, basements, garages, and utility rooms.
This furnace design has not been CSA certified for installa-
tion 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.
Lennox does not recommend the use of G71MPP 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.

Use of Furnace as Construction Heater

G71MPP 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.
D A room thermostat must control the furnace. The use of
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.
Air filters must be replaced upon construction comple-
D
tion.
The input rate and temperature rise must be set per the
D
furnace rating plate.
One hundred percent (100%) outdoor air must be pro-
D
vided for combustion air requirements during construc-
tion. Temporary ducting may supply outdoor air to the
furnace. Do not connect duct directly to the furnace.
The furnace heat exchanger, components, duct system,
D
air filters and evaporator coils must be thoroughly
cleaned following final construction clean−up.
All furnace operating conditions (including ignition, in-
D
put rate, temperature rise and venting) must be verified
according to these installation instructions.
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CAUTION