18
T O P
B O T T O M
S ID E
S ID E
S ID E
T O P
B O T T O M
U p flo w
C o u n te rflo w
H o riz on ta l
A furnace installed in a confined space (i.e., a closet or utility
room) must have two ventilation openings with a total minimum
free area of 0.25 square inches per 1,000 BTU/hr of furnace input
rating. Refer to Specification Sheet applicable to your model for
minimum clearances to combustible surfaces. One of the venti-
lation openings must be within 12 inches of the top; the other
opening must be within 12 inches of the bottom of the confined
space.
E
XISTING
F
URNACE
R
EMOVAL
NOTE:
When an existing furnace is removed from a venting sys-
tem serving other appliances,
the venting system may be too
large to properly vent the remaining attached appliances.
The following vent testing procedure is reproduced from the
Ameri-
can National Standard/National Standard of Canada for
Gas-Fired Central Furnaces ANSI Z21.4,
CSA-2.3 latest edition Section 1.23.1.
The following steps shall be followed with each appliance connected
to the venting system placed in operation, while any other appliances
connected to the venting system are not in operation:
1. Seal any unused openings in the venting system;
2. Inspect the venting system for proper size and horizontal
pitch, as required by the National Fuel Gas Code, ANSI
Z223.1 or the Natural Gas and Propane Installation Code,
CSA B149.1-05 and these instructions. Determine that
there is no blockage or restriction, leakage, corrosion and
other deficiencies which could cause an unsafe condition.
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 oper-
ate 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 operate continuously.
7. Test for spillage from draft hood appliances at the draft
hood relief opening after 5 minutes of main burner opera-
tion. Use the flame of a match or candle.
8. 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 National Gas and Propane Installation Code CSA
B149.1-05.
9. After it has been determined that each appliance con-
nected to the venting system properly vents when tested as
outlined above, return doors, windows, exhaust fans, fire-
place dampers and any other gas burning appliance to
their previous conditions of use.
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 CSA B149.1-05
Installation Codes.
T
HERMOSTAT
L
OCATION
The thermostat should be placed approximately five feet from
the floor on a vibration-free, inside wall in an area having good air
circulation. Do not install the thermostat where it may be influ-
enced 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.
Combustion & Ventilation Air Requirements
T
O
AVOID
PROPERTY
DAMAGE
,
PERSONAL
INJURY
OR
DEATH
,
SUFFICIENT
FRESH
AIR
FOR
PROPER
COMBUSTION
AND
VENTILATION
OF
FLUE
GASES
MUST
BE
SUPPLIED
. M
OST
HOMES
REQUIRE
OUTSIDE
AIR
BE
SUPPLIED
INTO
THE
FURNACE
AREA
.
WARNING
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 com-
bustion 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 car-
bon monoxide.
PRODUCT DESIGN
