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Filter Removal
Depending on the installation, differing filter arrangements
can be applied. Filters can be installed in either the central
return register or a side panel external filter rack (upflow
only). A media air filter or electronic air cleaner can be used
as an alternate filter. Follow the filter sizes given in the Rec
-
ommended Minimum Filter size table or instruction provided
by the media or electronic air cleaner manufacturer to ensure
proper unit performance.
To remove filters from an external filter rack in an upright up
-
flow installation, follow the directions provided with external
filter rack kit.
Induced Draft and Circulator Blower Motors
The bearings in the induced draft blower and circulator blow-
er motors are permanently lubricated by the manufacturer.
No further lubrication is required. Check motor windings for
accumulation of dust which may cause overheating. Clean
as necessary.
Flame Sensor (Qualified Servicer Only)
Under some conditions, the fuel or air supply can create a
nearly invisible coating on the flame sensor. This coating
acts as an insulator causing a drop in the flame sense sig
-
nal. If the flame sense signal drops too low the furnace will
not sense flame and will lock out. The flame sensor should
be carefully cleaned by a qualified servicer using steel wool.
The flame sense signal should be 1 to 3 microamps.
Igniter (Qualified Servicer Only)
At room temperature, the igniter ohm reading should be from
37 - 68 ohms.
Burners
WARNING
To prevent personal injury or death, do not remove any
internal compartment covers or attempt any adjustment.
Electrical components are contained in both compartments.
Contact a qualified service agent at once if an abnormal
flame appearance should develop.
Periodically during the heating season, make a visual check
of the burner flames. Turn the furnace on at the thermostat.
Wait a few minutes, since any dislodged dust will alter the
normal flame appearance. Flames should be stable, quiet,
soft and blue with slightly orange tips. They should not be
yellow. They should extend directly outward from the burner
ports without curling downward, floating or lifting off the ports.
Cleaning (Qualified Servicer Only)
1.
Shut off electric power and gas supply to the furnace.
2.
Disconnect the rollout limit wires, flame sensor wire,
and disconnect the igniter plug.
CAUTION
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and dangerous
operation. Verify proper operation after servicing.
3. Remove four (4) screws securing the burner box top.
CAUTION
The igniter is fragile and can be easily damage. Use extreme
caution when removing the burner box top.
4. Remove the screws securing the burners to the burner
bracket. Remove the burners.
5.
Use bottle brush to clean burner insert and inside of
burner.
6. Replace burner (opposite of removal). Ensure burners
are fully seated on burner bracket and are properly
aligned. Replace burner box top. Reconnect wiring.
7. Turn on electric power and gas supply to the furnace.
8. Check furnace for proper operation. Refer to
“Operational
Checks”
section to verify burner flame characteristics.
BEFORE LEAVING AN INSTALLATION
• Cycle the furnace with the thermostat at least three
times. Verify cooling and fan only operation.
• Review the Owner’s Manual with the homeowner and
discuss proper furnace operation and maintenance.
• Leave literature packet near furnace.
REPAIR AND REPLACEMENT PARTS
• When ordering any of the listed functional parts, be
sure to provide the furnace model, manufacturing, and
serial numbers with the order.
• Although only functional parts are shown in the parts
list, all sheet metal parts, doors, etc. may be ordered
by description.
• Parts are available from your distributor.
Functional Parts List-
Blower/Collector Box Gasket Gas Valve
Natural Gas Orifice
Primary Limit Switch
Propane Gas Orifice
Rollout Limit Switch
Burner
Auxiliary Limit Switch
Hot Surface Igniter
Heat Exchanger
Flame Sensor
Door Switch
Gas Manifold
Transformer
Ignition Control
Blower Wheel
Blower Mounting Bracket
Blower Housing
Pressure Switch
Blower Cutoff
Pressure Switch Hose
Blower Motor
Induced Draft Blower
Motor Mount Bracket
Collector Box
Capacitor
