4
TRANSPORTATION DAMAGE
Check the furnace for any shipping damage. If damage is
found, contact the company where the furnace was pur-
chased.
While checking for transportation damage, remove all
packaging material and dispose or recycle according to
local codes.
THERMOSTAT REQUIREMENTS
The two stage furnace requires a two stage thermostat for
proper operation. A two stage thermostat will have a “W2”
terminal in addition to a “W1” terminal. Refer to Section VI
for proper hookup.
THERMOSTAT LOCATION
Locate the thermostat about 5 feet high on a vibration-free
inside wall, in an area having good air circulation
Do not install the thermostat where it may be affected by:
• drafts or dead spots behind door, in corners or under
cabinets.
• hot or cold air from ducts.
• radiant heat from sun or appliances.
• concealed pipes and chimneys.
• unheated (uncooled) areas behind the thermostat,
such as an outside wall.
Consult the instructions packaged with the thermostat for
mounting instructions.
III. Combustion and Ventilation Air
Requirements
WARNING
Possible death, personal injury or property
damage may occur if the furnace and other
fuel-burning appliances are not provided
with enough fresh air for proper
combustion and ventilation of flue gases.
Most homes require outside air to be
supplied into the furnace area.
Improved construction and additional insulation in buildings
has reduced the heat loss, making these buildings much
tighter around doors and windows so air infiltration is
minimal. This creates a problem supplying combustion and
ventilation air for gas fired and other fuel burning appli-
ances. Use of appliances pulling air out of the house
(clothes dryers, exhaust fans, fireplaces, etc.) increases
this problem causing appliances to starve for air.
This furnace must use indoor air for combustion. It cannot
be installed as a direct vent (i.e., sealed combustion)
furnace. The burner box is present only to help reduce
sound transmission from the burners to the occupied space.
AIR REQUIREMENTS
Most homes will require outside air be supplied to the
furnace area by means of ventilation grilles or ducts con-
necting directly to the outdoors or spaces open to the
outdoors such as attics or crawl spaces.
The following information on air for combustion and venti-
lation is reproduced from the
National Fuel Gas Code
NFPA 54/ANSI Z223.1 Section 5.3.
5.3.1 General:
(a) The provisions of 5.3 apply to gas utilization equipment in-
stalled in buildings and which require air for combustion,
ventilation and dilution of flue gases from within the building.
They do not apply to (1) direct vent equipment which is
constructed and installed so that all air combustion is obtained
from the outside atmosphere and all flue gases are discharged to
the outside atmosphere, or (2) enclosed furnaces which incor-
porate an integral total enclosure and use only outside air for
combustion and dilution of flue gases.
(b) Equipment shall be installed in a location in which the facilities
for ventilation permit satisfactory combustion of gas, proper
venting and the maintenance of ambient temperature at safe
limits under normal conditions of use. Equipment shall be
located so as not to interfere with proper circulation of air. When
normal infiltration does not provide the necessary air, outside
air shall be introduced.
(c) In addition to air needed for combustion, process air shall be
provided as required for: cooling of equipment or material,
controlling dew point, heating, drying, oxidation or dilution,
safety exhaust, odor control, and air for compressors.
(d) In addition to air needed for combustion, air shall be supplied for
ventilation, including all air required for comfort and proper
working conditions for personnel.
(e) While all forms of building construction cannot be covered in
detail, air for combustion, ventilation and dilution of flue gases
for gas utilization equipment vented by natural draft normally
may be obtained by application of one of the methods covered
in 5.3.3 and 5.3.4.
(f) Air requirements for the operation of exhaust fans, kitchen
ventilation systems, clothes dryers, and fireplaces shall be
considered in determining the adequacy of a space to provide
combustion air requirements.
5.3.2 Equipment Located in Unconfined Spaces:
In unconfined spaces (see definition below) in buildings, infiltra-
tion may be adequate to provide air for combustion ventilation
and dilution of flue gases. However, in buildings of tight
construction (for example, weather stripping, heavily insulated,
caulked, vapor barrier, etc.) additional air may need to be
provided using the methods described in 5.3.3-b or 5.3.4.
Space, Unconfined. For purposes of this Code, a space whose
volume is not less than 50 cubic feet per 1,000 BTU per hour of
the aggregate input rating of all appliances installed in that
space. Rooms communicating directly with the space in which
the appliances are installed through openings not furnished with
doors, are considered a part of the unconfined space.
5.3.3 Equipment Located in Confined Spaces:
(a) All Air from Inside the Building: The confined space shall be
provided with two permanent openings communicating directly
with an additional room(s) of sufficient volume so that the
combined volume of all spaces meets the criteria for an uncon-
fined space. The total input of all gas utilization equipment
