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The information listed below is for reference purposes only
and does not necessarily have jurisdiction over local or state
codes. Always consult with local authorities before installing
any gas appliance.
Combustion & Ventilation Air
• US: National Fuel Gas Code (NFGC), Air for Combustion
and Ventilation
• CANADA: Natural Gas and Propane Installation Codes
(NSCNGPIC), Venting Systems and Air Supply for
Appliances
Duct Systems
• US and CANADA: Air Conditioning Contractors Association
(ACCA) Manual D, Sheet Metal and Air Conditioning
Contractors National Association (SMACNA), or American
Society of Heating, Refrigeration, and Air Conditioning
Engineers (ASHRAE) Fundamentals Handbook
Electrical Connections
• US: National Electrical Code (NEC) ANSI/NFPA 70
• CANADA: Canadian Electrical Code CSA C22.1
Gas Piping & Gas Pipe Pressure Testing
• US: NFGC and National Plumbing Codes
• CANADA: NSCNGPIC
General Installation
• US: Current edition of the NFGC and the NFPA 90B. For
copies, contact the National Fire Protection Association Inc.,
Batterymarch Park, Quincy, MA 02269; or American Gas
Association, 400 N. Capitol, N.W., Washington DC 20001
or www.NFPA.org
• CANADA: NSCNGPIC. For a copy, contact Standard Sales,
CSA International, 178 Rexdale Boulevard, Etobicoke
(Toronto), Ontario, M9W 1R3 Canada
Safety
• US:(NFGC) NFPA 54–1999/ANSI Z223.1 and the Installation
Standards, Warm Air Heating and Air Conditioning Systems
ANSI/NFPA 90B.
• CANADA:CAN/CGA-B149.1 and .2–M00 National Standard
of Canada. (NSCNGPIC)
Combustion Air Quality
CAUTION:
Combustion air must not be drawn from a
corrosive atmosphere.
To maximize heat exchanger life, the combustion air
must be free of chemicals that can form corrosive acidic
compounds in the combustion gases. The recommended
source of combustion air is to use outdoor air. However,
the use of indoor air in most applications is acceptable
except as listed:
• If the furnace is installed in a confined space, it is
required that the necessary combustion air come from
the outdoors by way of attic, crawl space, air duct, or
direct opening. For Installations in confined spaces, see
page 7
for combustion air requirements.
• Installations in these locations may require outdoor air
for combustion, due to chemical exposures:
Commercial buildings
Buildings with indoor pools
Furnaces installed in laundry rooms
Furnaces installed in hobby or craft rooms
• Exposure to the following substances in the combustion
air supply may require outdoor air for combustion:
Permanent wave solutions
Chlorinated waxes and cleaners
Chlorine based swimming pool chemicals
Water softening chemicals
De-icing salts or chemicals
Carbon Tetrachloride
Halogen type refrigerants
Cleaning solvents (perchloroethylene)
Printing inks, paint removers, varnishes, etc.
Hydrochloric Acid
Cements and glues
Antistatic fabric softeners
Masonry acid washing materials
Heating Load
This furnace should be sized to provide the design heating
load requirement. Heating load estimates can be made
using approved methods available from Air Conditioning
Contractors of America (Manual J); American Society of
Heating, Refrigerating, and Air Conditioning Engineers;
or other approved engineering methods. Excessive
oversizing of the furnace could cause the furnace
and/or vent to fail prematurely. The ductwork should
be appropriately sized to the capacity of the furnace to
ensure its proper airflow rating.
For installations above 2,000 ft., the furnace should have
a sea level input rating large enough that it will meet the
heating load after deration for altitude.
Two-stage furnaces operate at two input rates to better
meet heating loads. The lower heating rate (low fire) is
65% of the high fire rate. The greatest degree of control
over the furnace can be gained by controlling it with a two
stage thermostat. This allows the thermostat to directly
request either high or low fire. However, it is possible to
operate the furnace using a single stage thermostat. In
this application the furnace control can be set to increase
from low to high fire, based on a timer. See Autostaging
for Single Stage Thermostats
Furnaces are properly sized to meet the expected
maximum heating load. But this load occurs infrequently.
So, during more moderate weather, the furnace is likely to
use low fire a considerable part of the time. This is normal
and has the benefit of quieter and more efficient operation.
Installation in a Garage
This Gas-fired furnace may be installed in a residential
garage with the provision that the burners and igniter
are located no less than 18 inches (457mm) above the
floor. The furnace must be located or protected to prevent
physical damage by vehicles.
(page
26).
5
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