3. As far as practical, close all building doors and windows and
all doors between the space in which the appliance(s)
connected to the venting system are located and other
spaces of the building.
4. Close fireplace dampers.
5. Turn on clothes dryers and any appliance not connected to
the venting system. Turn on any exhaust fans, such as range
hoods and bathroom exhausts, so they shall operate at
maximum speed. Do not operate a summer exhaust fan.
6. Follow the lighting instructions. Place the appliance being
inspected in operation. Adjust thermostat so appliance shall
7. Test for spillage from draft hood appliances at the draft hood
relief opening after 5 minutes of main burner operation. Use
the flame of a match or candle.
8. After it has been determined that each appliance connected
to the venting system properly vents when tested as outlined
above, return doors, windows, exhaust fans, fireplace
dampers and any other gas-burning appliance to their
previous conditions of use.
9. If improper venting is observed during any of the above tests,
the venting system must be corrected in accordance with the
National Fuel Gas Code ANSI Z223.1/NFPA 54 and/or CAN/
CSA B149 Installation Codes.
COMBUSTION AND VENTILATION AIR REQUIREMENTS
To avoid property damage, personal injury or death,
sufficient fresh air for proper combustion and ventilation
of flue gases must be supplied. Most homes require
outside air be supplied into the furnace area.
Improved construction and additional insulation in buildings have
reduced heat loss by reducing air infiltration and escape around
doors and windows. These changes have helped in reducing
heating/cooling costs but have created a problem supplying
combustion and ventilation air for gas-fired and other
fuel-burning appliances. Appliances that pull air out of the house
(clothes dryers, exhaust fans, fireplaces, etc.) increase the
problem by starving appliances for air.
House depressurization can cause back drafting or improper
combustion of gas-fired appliances, thereby exposing building
occupants to gas combustion products that could include carbon
If this furnace is to be installed in the same space with other gas
appliances, such as a water heater, ensure that there is an
adequate supply of combustion and ventilation air for the other
appliances. Refer to the latest edition of the National Fuel Gas
Code NFPA 54/ANSI Z223.1 or CAN/CSA B149 Installation
Codes or applicable provisions of the local building codes for
determining the combustion air requirements for the appliances.
NOTE: This furnace must use indoor air for combusion. It cannot
be installed as a direct vent, or sealed combustion, furnace.
Most homes will require outside air to be supplied to the furnace
area by means of ventilation grilles or ducts connecting directly
to the outdoors or spaces open to the outdoors such as attics or
If resizing is required on any portion of the venting system, use
the appropriate table in Appendix G in the latest edition of the
National Fuel Gas Code ANSI Z223.1 and/or CAN/CSA B149
The thermostat should be placed approximately 5 ft (1.5 m) from the
floor on a vibration-free, inside wall in an area having good air
NOTE: Do not install the thermostat where it may be influenced
by any of the following:
Drafts, or dead spots behind doors, in corners or under cabinets
Hot or cold air from registers
Radiant heat from the sun
Light fixtures or other appliances
Radiant heat from a fireplace
Concealed hot or cold water pipes or chimneys
Unconditioned areas behind the thermostat, such as an outside wall
Consult the instructions packaged with the thermostat for
mounting instructions and further precautions.
Category I Venting—Vertical Venting
To prevent possible personal injury or death due to
asphyxiation, this furnace must be Category I vented.
Do not vent using Category III venting.
Provisions must be made for venting combustion
products outdoors through a proper venting system.
The length of flue pipe could be a limiting factor in
locating the furnace.
Category I Venting is venting at a nonpositive pressure. A furnace
vented as Category I is considered a fan-assisted appliance. The
vent system does not have to be "gas tight."
NOTE: Single-stage gas furnaces with induced draft blowers
draw products of combustion through a heat exchanger allowing,
in some instances, common venting with natural draft appliances
(for example, water heaters).
All installations must be vented in accordance with National Fuel
Gas Code NFPA 54/ANSI Z223.1—latest edition. In Canada, the
furnaces must be vented in accordance with the National
Standard of Canada, CAN/CSA B149.1 and CAN/CSA B149.2—
latest editions and amendments.
NOTE: The vertical height of the Category I venting system must
be at least as great as the horizontal length of the venting system.
To prevent possible personal injury or death, due to
asphyxiation, common venting with other manufacturer's
induced draft appliances is not allowed.