Service Guide

SYSTEM OPERATION
9
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 R SS Q  RR  RS
JR R     S S  SR
 S  
Follow the instructions listed below when selecting a
furnace location. Refer also to the guidelines provided in the
Combustion and Ventilation Air Requirements section in this
manual or the installation instructions for details.
• Centrally locate the furnace with respect to the proposed
or existing air distribution system.
• Ensure the temperature of the return air entering the
furnace is between 55°F and 100°F when the furnace
is heating.
• If the furnace is installed in an application where the
typical operating sound level of a furnace is deemed
objectionable, an optional sound reduction kit is
available. Consult your local distributor for more details.
• Provide provisions for venting combustion products
outdoors through a proper venting system. Special
consideration should be given to vent/ue pipe routing
and combustion air intake pipe when applicable.
•   All installations must be vented in
accordance with National Fuel Gas Code, NFPA 54/ANSI
Z223.1 - lateset edition. In Canada the furnaces must
be vented in accordance with the National Standard of
Canada, CAN/CGA B149.
• Ensure upow or horizontal furnaces are not installed
directly on carpeting, or any other combustible material.
The only combustible material allowed is wood.
• A special accessory subbase must be used for upright
counterflow unit installations over any combustible
material (including wood). Refer to subbase instructions
for installation details. ( A subbase will not be
required if an air conditioning coil is located beneath
the furnace between the supply air opening and the
combustible oor.
• Exposure to contaminated combustion air will result in
safety and performance-related problems. Do not install
the furnace where the combustion air is exposed to the
following substances:
chlorinated waxes or cleaners
chlorine-based swimming pool chemicals
water softening chemicals
deicing salts or chemicals
carbon tetrachloride
halogen type refrigerants
cleaning solutions (such as perchloroethylene)
printing inks
paint removers
varnishes
hydrochloric acid
cements and glues
antistatic fabric softeners for clothes dryers
and masonry acid washing materials
• Seal o󰀨 a non-direct vent furnace if it is installed near
an area frequently contaminated by any of the above
substances. This protects the non-direct vent furnace
from airborne contaminants. To ensure that the enclosed
non-direct vent furnace has an adequate supply of
combustion air, vent from a nearby uncontaminated
room or from outdoors. Refer to the Combustion and
Ventilation Air Requirements section in this manual or
the installation instructions for details.
• If the furnace is used in connection with a cooling unit,
install the furnace upstream or in parallel with the cooling
unit coil. Premature heat exchanger failure will result if
the cooling unit coil is placed ahead of the furnace.
• If the furnace is installed in a residential garage, position
the furnace so that the burners and ignition source are
located not less than 18 inches (457 mm) above the oor.
Protect the furnace from physical damage by vehicles.
• If the furnace is installed horizontally, the furnace access
doors must be vertical so that the burners re horizontally
into the heat exchanger. Do not install the unit with the
access doors on the “up/top” or “down/bottom” side of
the furnace.

Installations must adhere to the clearances to combustible
materials to which this furnace has been design certied. The
minimum clearance information for this furnace is provided
on the unit’s clearance label. These clearances must be
permanently maintained. Refer to Specication Sheet for
minimum clearances to combustible materials. Clearances
must also accommodate an installation’s gas, electrical, and
drain trap and drain line connections.  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 conned 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. 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 conned space. In a typical
construction, the clearance between the door and door frame
is usually adequate to satisfy this ventilation requirement.