3. After touching the chassis you may proceed to service the
control or connecting wires as long as you do nothing that
recharges your body with static electricity (for example; DO
NOT move or shuffle your feet, DO NOT touch un-
grounded objects, etc.).
4. If you touch ungrounded objects (recharge your body with
static electricity), firmly touch furnace again before touch-
ing control or wires.
5. Use this procedure for installed and uninstalled (un-
grounded) furnaces.
6. Before removing a new control from its container, dis-
charge your body’s electrostatic charge to ground to protect
the control from damage. If the control is to be installed in
a furnace, follow items 1 through 5 before bringing the
control or yourself into contact with the furnace. Put all
used AND new controls into containers before touching
ungrounded objects.
7. An ESD service kit (available from commercial sources)
may also be used to prevent ESD damage.
INTRODUCTION
The model 373LAV Series E Furnaces are available in sizes
50,000 through 135,000 Btuh input capacities.
The design of the downflow/horizontal gas-fired furnace is
A.G.A./C.G.A. certified for natural and propane gas and for
installation on noncombustible flooring. The furnace may be
installed on combustible flooring when installed with the acces-
sory downflow subbase. This furnace is for installation in alcoves,
attics, crawlspaces, basements, closets, or utility rooms. The
design of this furnace line is not A.G.A./C.G.A. certified for
installation in mobile homes, recreation vehicles, or outdoors.
Before installing the furnace, refer to the current edition of the
NFGC. Canadian installations must be installed in accordance
NSCNGPIC and all authorities having jurisdiction. For further
information, the NFGC is available from National Fire Protection
Association Inc., Batterymarch Park, Quincy, MA 02269; Ameri-
can Gas Association, 1515 Wilson Boulevard, Arlington, VA
22209; or from Literature Distribution.
CAUTION:
Application of this furnace should be in-
doors with special attention given to vent sizing and
material, gas input rate, air temperature rise, and unit
sizing. Improper installation or misapplication of the
furnace can require excessive servicing or cause prema-
ture component failure.
Installation must conform to the regulations of the serving gas
supplier and the local building, heating, and plumbing codes in
effect in the area in which the installation is made, or in the
absence of local codes with the requirements of the NFGC.
This furnace is designed for a minimum continuous return-air
temperature of 60°F db or intermittent operation down to 55°F db
such as when used with a night setback thermostat. Return-air
temperature must not exceed a maximum of 85°F db.
WARNING:
Improper installation, adjustment, alter-
ation, service, maintenance, or use can cause carbon
monoxide poisoning, explosion, fire, electrical shock, or
other conditions which may cause personal injury, loss of
life, or property damage. Consult a qualified installer,
service agency, local gas supplier, or your distributor or
branch for information or assistance. The qualified in-
staller or agency must use only factory-authorized and
listed kits or accessories when modifying this product.
Failure to follow this warning could result in electrical
shock, fire, personal injury, or death.
For accessory installation details, refer to the applicable installa-
tion literature.
NOTE:
Remove all shipping brackets and materials before oper-
ating the furnace.
I.
LOCATION
A.
General
CAUTION:
Do not install furnace in a corrosive or
contaminated atmosphere. Make sure all combustion and
circulating air requirements are followed, in addition to
all local codes and ordinances.
Do not use this furnace during construction when adhe-
sives, sealers, and/or new carpets are being installed. If
the furnace is required during construction, use clean
outside air for combustion and ventilation. Compounds of
chlorine and fluorine when burned with combustion air
form acids which cause corrosion of the heat exchangers
and metal vent system. Some of these compounds are
found in paneling and dry wall adhesives, paints, thin-
ners, masonry cleaning materials, and many other sol-
vents commonly used in the construction process.
This furnace must be installed so the electrical components are
protected from water.
Locate the furnace as close to the chimney/vent and as near the
center of the air distribution system as possible. The furnace
should be installed as level as possible.
When a furnace is installed so that the supply ducts carry air to
areas outside the space containing the furnace, the return air must
also be handled by a duct(s) sealed to the furnace casing and
terminating outside the space containing the furnace.
Provide ample space for servicing and cleaning. Always comply
with the minimum fire protection clearances shown on the unit
rating plate. This furnace shall not be installed directly on
carpeting, tile, or any combustible material other than wood
flooring. The furnace may be installed on combustible flooring
when installed with the accessory downflow subbase, which is
available from your distributor or branch when required.
B.
Location Relative to Cooling Equipment
The cooling coil must be installed parallel with or on the
downstream side of the furnace to avoid condensation in the heat
exchangers. When installed parallel with a furnace, dampers or
other means used to control the flow of air must prevent chilled air
from entering the unit. If the dampers are manually operated, they
must be equipped with means to prevent operation of either unit
unless the damper is in the full-heat or full-cool position.
C.
Hazardous Locations
When the furnace is installed in a residential garage, it must be
installed so that the burners and ignition source are located at least
18 in. above the floor. The furnace should be protected from
physical damage by vehicles.
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