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Combustion Air Inducer
A combustion air inducer proving switch checks
combustion air inducer operation before allowing power
to the gas controller. The gas controller will not operate if
the inducer is obstructed.
Under normal operating conditions, the combustion air
inducer wheel should be checked and cleaned prior to the
heating season. However, it should be examined
periodically during the heating season to establish an
ideal cleaning schedule.
Clean the combustion air inducer as follows:
1− Turn off the electrical power and the gas supply to the
unit.
2− Disconnect the pressure switch air tubing from the
combustion air inducer port.
3− Remove and retain the screws securing the
combustion air inducer to the flue box. Remove and
retain the screw securing the combustion air inducer
to the vent connector. See figure 3.
4− Clean the inducer wheel blades with a small brush
and wipe off any dust from the housing. Clean
accumulated dust from the front of the collector box
cover.
5− Return the combustion air inducer motor to the
original location and secure with retained screws. It
is recommended that the combustion air inducer
gasket be replaced during reassembly.
6− Use a small brush to clean the combustion air inlet
louvers on the heat access panel.
Flue Passageway and Flue Box
1− Remove the combustion air inducer assembly as
described in the Combustion Air Inducer subsection.
2− Remove the flue box cover. Clean the flue box with a
wire brush as required.
3− Clean the tubes with a wire brush.
4− Reassemble the unit. The flue box cover gasket and
combustion air inducer gasket should also be
replaced during reassembly.
Service Reminder
Call a qualified service technician if the unit is inoperative.
Before calling, always check the following to be sure
service is required:
1− Be sure electrical disconnect switches are
ON
.
2− Check room thermostat for proper setting.
3− Replace any blown fuses or reset circuit breakers.
4− Gas valve should be
ON
.
5− Air filters should not be plugged, limiting air flow.
6− Make sure all access panels are in place.
Repair Parts Listing
When ordering repair parts, include the complete model number and serial number listed on the ETL rating plate − e.g.
SGA480H4BH1Y.
Gas Heat Section Parts
Heat Exchanger
Combustion Air Assembly
Combustion Air Proving Switch
Burner Assembly
Burner Manifold Assembly
Main Burner Orifices
Flame Roll−out Switches
Auxiliary Limit Controls
Ignition Electrode Assembly
Ignition Lead
Ignition Sensor Assembly
Sensor Lead
Combination Gas Valve
Limit Controls
Cooling Parts
Compressors
Condenser Fan Motors
Condenser Fan Blades
Condenser Fan Run Capacitors
Freezestats
Condenser Fan Mounting Bracket
Fan Grille
Indoor Blower Motors
Blower Wheel
Expansion Valve
Distributor
Exhaust Fans (Opt.)
Electrical Control Parts
IMC Control Board
Compressor Contactors
Circuit Breakers (Opt.)
Transformer (Control)
Transformer (Contactor)
Blower Contactor
Limit, Blower Relay
Heat Relays
Condenser Fan Relays
Capacitor CAB
Relay CAB
Crankcase Heaters
Disconnect Switch (Opt.)
