8
POSITION*
SIDES
REAR
FRONT BOTTOM
FLUE
TOP
Upflow
0"
0"
3"
C
0"
1"
Horizontal
6"
0"
3"
C
0"
6"
C = If placed on combustible floor, floor MUST be wood only.
*MES[92 & 96]* MINIMUM CLEARANCES TO COMBUSTIBLE MATERIALS
(INCHES)
POSITION*
SIDES
REAR
FRONT BOTTOM
FLUE
TOP
Counterflow
0"
0"
3"
NC
0"
1"
Horizontal
6"
0"
3"
C
0"
6"
C = If placed on combustible floor, floor MUST be wood only.
NC = For installation on non-combustible floors only. A combustible subbase
must be used for installations on combustible flooring.
*CES[92 & 96]* MINIMUM CLEARANCES TO COMBUSTIBLE MATERIALS
(INCHES)
TOP
BOTTOM
SIDE
SIDE
SIDE
TOP
BOTTOM
Upflow
Counterflow
Horizontal
Figure 1
Clearances and Accessibility
NOTES:
• For servicing or cleaning, a 24” front clearance is
required.
• Unit connections (electrical, flue and drain) may
necessitate greater clearances than the minimum
clearances listed above.
• Clearance in accordance with local installation
codes, the requirements of the gas supplier and
the manufacturer’s installation instructions.
Dégaugement conforme aux codes d’installation
locaux, aux exigences du fournisseur de gaz et
aux instructions d’installation du fabricant.
• In all cases, accessibility clearance must take
precedence over clearances from the enclosure
where accessibility clearances are greater.
Installations must adhere to the clearances to combustible
materials to which this furnace has been design certified.
The minimum clearance information for this furnace is
provided on the unit’s clearance label. These clearances
must be permanently maintained. Clearances must also
accommodate an installation’s gas, electrical, and drain trap
and drain line connections. If the alternate combustion air
intake or vent/flue connections are used additional clear
-
ance must be provided to accommodate these connections.
Refer to
Vent/Flue Pipe and Combustion Air Pipe
for details.
NOTE:
In addition to the required clearances to combustible
materials, a minimum of 24 inches service clearance must be
available in front of the unit.
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 ventilation openings must be within 12 inches of the top;
the other opening must be within 12 inches of the bottom of
the confined space. In a typical construction, the clearance
between the door and door frame is usually adequate to satisfy
this ventilation requirement.
Existing Furnace Removal
NOTE:
When an existing furnace is removed from a venting
system serving other appliances,
the venting system may
be too large to properly vent the remaining attached ap-
pliances.
The following vent testing procedure is repro duced from
the
American National Standard/National Standard
of Canada for Gas-Fired Central Furnaces ANSI Z21.47,
CSA-2.3 latest edition Section 1.23.1.
Thermostat Location
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
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.
C
ombustion
& V
entilation
R
equiRements
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.
