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DOWNFLOW/HORIZONTAL
FURNACE COMPONENTS
Manual-Reset Auxiliary Limit Switch
(When Used)
Blower and Blower Motor
Relief Box
Gas Valve Control Knob or Electric Switch
(On/Off)
Gas Valve
Gas Burner
Rating Plate
Blower Door Safety Switch
Blocked Vent Safeguard Tube and Switch
Gas Manifold
Manual Reset Limit Switch (2)
Hot Surface Ignitor
Flame Sensor
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IMPORTANT FACTS
Your furnace must have adequate air-
flow for efficient combustion and safe
ventilation. Do not enclose it in an
airtight room or “seal’’ it behind solid
doors. To minimize the possibility of
serious personal injury, fire, damage
to your furnace, or improper operation;
carefully follow these safety rules:
• Keep the area around your furnace
free of combustible materials, gasoline,
and other flammable liquids and
vapors.
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• Do not cover the furnace, store trash
or debris near it, or in any way block
the flow of fresh air to the unit.
• Combustion air must be clean and
uncontaminated with chlorine or fluo-
rine. These compounds are present in
many products around the home, such
as: water softener salts, laundry
bleaches, detergents, adhesives, paints,
varnishes, paint strippers, waxes, and
plastics.
Make sure the combustion air for your
furnace does not contain any of these
compounds. During remodeling be
sure the combustion air is fresh and un-
contaminated. If these compounds are
burned in your furnace, the heat ex-
changers and metal vent system may
deteriorate.
• A furnace installed in the attic or
other insulated space must be kept free
and clear of the insulating material.
Examine the furnace area when install-
ing the furnace or adding more insula-
tion. Some materials may be
combustible.
NOTE:
Do not use this furnace if any
part has been under water. Immediately
call a qualified service technician to in-
spect the furnace and to replace any
part of the control system and any gas
control which has been under water.
NOTE:
The qualified installer or
agency must use only factory-
authorized re-placement parts, kits,
and accessories when modifying or
repairing this product.
This furnace contains safety devices
which must be manually reset. If the fur-
nace is left unattended for an extended
period of time, have it checked periodi-
cally for proper operation. This precau-
tion will prevent problems associated
with no heat, such as frozen water pipes,
etc. See “Before You Request a Service
Call’’ section in this manual.
SAFETY
CONSIDERATIONS
Installing and servicing heating
equipment can be hazardous due to
gas and electrical components. Only
trained and qualified personnel should
install, repair, or service heating
equipment.
Untrained personnel can perform basic
maintenance functions such as clean-
ing and replacing air filters. All other
operations must be performed by
trained service personnel. Observe
safety precautions in this manual, on
tags, and on labels attached to the fur-
nace and other safety precautions that
may apply.
Recognize safety information: This is
the safety-alert symbol
. When you
see this symbol on the furnace and in
instructions or manuals, be alert to the
potential for personal injury.
Understand the signal words—DAN-
GER, WARNING, and CAUTION.
These words are used with the
!
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