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Gas Furnaces
USER MANUAL
M4RC 92.1% AFUE Upfl ow
High Effi ciency Furnaces
Congratulations on the purchase on your new
furnace. With our dedication to quality, superior
reliability, and outstanding warranty, we know
you will be pleased with this new appliance. This
furnace has been designed and built to provide
many years of safe and dependable home comfort,
providing it is properly installed and regular
maintenance has been performed. Improper use
or insuffi cient maintenance can shorten the life of
the furnace and result in serious personal injury
or property damage. Please read this manual
thoroughly and familiarize yourself with the
safety, operation and maintenace procedures for
this furnace.
WARNING:
FIRE OR EXPLOSION HAZARD
• Failure to follow safety warnings exactly
could result in serious injury or property
damage.
• Do not store or use gasoline or other
fl ammable vapors and liquids in the vicinity
of this or any other appliance.
M4RL 92.1% AFUE Downfl ow
High Effi ciency Furnaces
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not
use any phone in your building.
• Leave the building immediately.
• Immediately call your gas supplier from a
neighbors phone. Follow the gas suppliers
instructions.
• If you cannot reach your gas supplier, call
the fi re department.
Installation and service must be performed
by a qualifi ed installer, service agency or the
gas supplier.
WARNING:
PROPOSITION 65 WARNING: This product
contains chemicals known to the state of
California to cause cancer, birth defects or
other reproductive harm.
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Table of Contents
Safety Information .....................................................................................................................3
Air for Proper Combustion ....................................................................................................3
Flammable Vapors ...............................................................................................................3
Gas Supply and Piping ........................................................................................................3
Venting System ....................................................................................................................4
Combustibles .......................................................................................................................4
Flood Damage .....................................................................................................................4
Shutting Down the Furnace .................................................................................................4
Inspection .............................................................................................................................4
Filters ...................................................................................................................................4
Description of Furnace .............................................................................................................5
Furnaces Components.........................................................................................................5
Venting System ....................................................................................................................5
Category IV Furnaces ....................................................................................................5
Combustion Air Requirements .................................................................................................5
Sources of Corrosion ...........................................................................................................5
Furnace in Small Room or Closet ........................................................................................5
Startup and Shutdown ..............................................................................................................6
Starting the Furnace ............................................................................................................6
Shutting Down the Furnace .................................................................................................6
Inspection ...................................................................................................................................6
Frequency ............................................................................................................................6
Venting System ....................................................................................................................6
Blower and Filter .................................................................................................................6
Air for Combustion ...............................................................................................................6
Air for Comfort ......................................................................................................................6
Burner Operation ................................................................................................................7
New Construction ................................................................................................................7
Troubleshooting .........................................................................................................................7
Location of Furnace Components ...........................................................................................8
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SAFETY INFORMATION
WARNING:
The safety information listed throughout this
manual must be followed during the installation,
service, and operation of this furnace. Failure
to follow safety recommendations could result
in possible damage to the equipment, serious
per
sonal injury, or death
.
Gas Supply and Piping
This furnace does not have a pilot. It is equipped with an
ignition device which automatically lights the burner. DO
NOT try to light the burner by hand.
BEFORE OPERATING smell all around the furnace area
for gas. Be sure to smell next to the fl oor because some
gas is heavier than air and will settle to the fl oor.
Safety markings are used frequently throughout this
manual to designate a degree or level of seriousness and
should not be ignored. WARNING indicates a potentially
hazardous situation that if not avoided, could result in
personal injury or death. CAUTION indicates a potentially
hazardous situation that if not avoided, may result in minor
or moderate injury or property damage.
Air for Proper Combustion
WARNING:
Do not reduce the supply of fresh air to the
furnace. This could create the production of
excessive amounts of Carbon Monoxide - a
colorless, odorless gas that is a deadly poison
that could result in serious personal injury
or death. Do not block any openings that are
supplying fresh air to the room or closet the
furnace is in. If your furnace obtains its air
through a pipe to the outdoors, do not allow
the inlet of the pipe to become blocked.
Flammable Vapors
WARNING:
Do not place combustible materials on or against
the furnace cabinet or within 6 inches of the
vent pipe. Do not place combustible materials,
including gasoline or any other fl ammable
vapors and liquids, in the vicinity of the furnace.
A fi re or explosion may result causing property
damage, personal injury or loss of life. Failure to
follow the safety warnings exactly could result
in serious injury, death or property damage.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not
use any phone in your building.
• Leave the building immediately.
• Immediately call your gas supplier from a
neighbors phone. Follow the gas suppliers
instructions.
• If you cannot reach your gas supplier, call
the fi re department.
Installation and service must be performed by
a qualifi ed installer, service agency or the gas
supplier.
WARNING:
All gas piping and shutoff valves must be
installed in compliance with local codes and
utility regulations by licensed installers. DO
NOT attempt to modify, or tap into existing
gas lines yourself. Fire or explosion may result
causing property damage, personal injury or
loss of life. Failure to follow the safety warnings
exactly could result in serious injury, death or
property damage.
WARNING:
The furnace was shipped from the factory
equipped to operate on natural gas. Conversion
to LP/propane gas must be performed by a
licensed HVAC technician using a factory
supplied conversion kit. Failure to use the
proper conversion kit can cause fi re, explosion,
property damage, carbon monoxide poisoning,
personal injury, or death.
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