-- 18 --
Step 3—Hazardous Locations
FIRE, EXPLOSION, INJURY OR DEATH HAZARD
Failure to follow this warning could result in personal injury,
death or property damage.
When furnace is installed in a residential garage, it must be
installed so that burners and ignition sources are located a
minimum of 18 in. (457 mm) above floor. The furnace must
be located or protected to avoid physical damage by vehicles.
When furnace is installed in a public garage, airplane hangar,
or other building having a hazardous atmosphere, the furnace
must be installed in accordance with NFGC or NSCNGPIC.
(See Fig. 17.)
!
WARNING
Step 4—Furnace Location and Application
DIRECT VENT (2-PIPE) APPLICATION
Furnace may be located in a confined space without special
provisions for dilution or ventilation air.
18-IN. (457.2 mm)
MINIMUM TO BURNERS
A93044
Fig. 17 -- Installation in a Garage
NON-DIRECT VENT (1-PIPE) APPLICATION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in intermittent
unit operation.
Do not install furnace in a corrosive or contaminated
atmosphere. Make sure all combustion and circulating air
requirements are met.
CAUTION
!
Refer to the AIR FOR COMBUSTION AND VENTILATION
section for details.
AIR FOR COMBUSTION AND
VENTILATION
Provisions for adequate combustion, ventilation, and dilution air
must be provided in accordance with:
S
U.S. Installations:
Section 9.3 NFPA 54/ANSI Z223.1----2006,
Air for Combustion and Ventilation and applicable provisions
of the local building codes.
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Canadian Installations:
Part 8 of CAN/CS----B149.1----05,
Venting Systems and Air Supply for Appliances and all
authorities having jurisdiction.
FURNACE CORROSION HAZARD
Failure to follow this warning could result in reduced furnace
component life.
Air for combustion must not be contaminated by halogen
compounds, which include fluoride, chloride, bromide, and
iodide. These elements could corrode heat exchangers and
shorten furnace life. Air contaminants are found in aerosol
sprays, detergents, bleaches, cleaning solvents, salts, air
fresheners, and other household products.
!
WARNING
The following types of furnace installations may require
OUTDOOR AIR for combustion due to chemical exposures:
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Commercial buildings
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Buildings with indoor pools
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Laundry rooms
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Hobby or craft rooms, and
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Chemical storage areas
If air is exposed to the following substances, it should not be used
for combustion air, and outdoor air may be required
for combustion:
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Permanent wave solutions
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Chlorinated waxes and cleaners
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Chlorine based swimming pool chemicals
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Water softening chemicals
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De-icing salts or chemicals
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Carbon tetrachloride
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Halogen type refrigerants
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Cleaning solvents (such as perchloroethylene)
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Printing inks, paint removers, varnishes, etc.
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Hydrochloric acid
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Cements and glues
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Antistatic fabric softeners for clothes dryers
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Masonry acid washing materials
All fuel-burning equipment must be supplied with air for fuel
combustion. Sufficient air
must
be provided to avoid negative
pressure in the equipment room or space. A positive seal
must
be
made between the furnace cabinet and the return-air duct to
prevent pulling air from the burner area and from draft
safeguard opening.
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury
or death.
The operation of exhaust fans, kitchen ventilation fans, clothes
dryers, attic exhaust fans or fireplaces could create a
NEGATIVE PRESSURE CONDITION at the furnace.
Make-up air MUST be provided for the ventilation devices, in
addition to that required by the furnace. Refer to the Carbon
Monoxide Poisoning Hazard warning in the venting section of
these instructions to determine if an adequate amount of
make-up air is available.
!
WARNING
The requirements for combustion and ventilation air depend upon
whether or not the furnace is located in a space having a volume
of at least 50 cubic feet per 1,000 Btuh input rating for all gas
appliances installed in the space.
S
Spaces having less than 50 cubic feet per 1,000 Btuh require
the
OUTDOOR COMBUSTION AIR
METHOD.
