Use Of Furnace As Construction Heater - Lennox ML195UH Installation Instructions Manual

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 10. Accessibility and ser-
vice clearances must take precedence over fire protection
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 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 standards.
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 and premature heat
exchanger failure.
This ML195UH furnace must be installed so that its electri-
cal 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, cool-
ing coils 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.
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 continu-
ous return air temperature of 60°F (16°C) or an intermit-
tent 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.
The ML195UH 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 ML195UH 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.
ML195UH 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.
Page 5
Dampers
Gas Unit
AIR FLOW
Air Handler Unit
Dampers
Gas Unit
AIR FLOW
FIGURE 3