17
SECTION V: SERVICE AND TROUBLESHOOTING
NORMAL OPERATION CHECK OF BURNER
1. Appliance calls for heat by raising the thermostat to the desired setting. Note the transformer is always energized with
120 volts.
2. When the thermostat circuit is complete, this allows 24 volts to coil side of the fan relay which are the bottom
terminals.
3. Now that 24 volts (yellow wires) are applied to the coil, this in turn allows the 120 volt contacts to close thus allowing
120 volts to flow to the fan across terminals #2 and #4 which are in series with the fan motor.
4. The combustion fan motor should now be energized.
5. With the fan energized, there will be a 30 second pre-purge.
6. The fan motor will develop 3400 rpm quickly causing the centrifugal endswitch to close. The endswitch can be
identified by the two red wires coming from the end cap of the fan motor.
7. After the endswitch makes, this allows 24 volts to the direct ignition control.
8. Now the ignition process will follow.
9. The direct ignition control will generate a high frequency spark at the same time the gas valve opens. The ignition
control has a 4 second trial for ignition period. If after four seconds the control does not sense a minimum flame signal
of 0.1 microamps then the control will enter into another 30 second pre-purge period followed by a second trial for
ignition. This process will be repeated a third time if necessary. If after three tries for ignition, the control does not
sense a flame, it will go into lockout. To reset the control simply cycle the thermostat off and then set it to the desired
temperature.
10. After the burner is operational, the control shifts into a rectification mode constantly monitoring the flame signal.
11. The burner will now cycle off and on based on the thermostat setting.
TROUBLESHOOTING GUIDE
NOTE 1: BURNERS ARE NOT PRESET FROM THE FACTORY AND MUST BE ADJUSTED AT THE SITE.
NOTE 2: NEW GAS LINE INSTALLATIONS WILL HAVE AIR IN THE LINES AND REQUIRE SEVERAL IGNITION
ATTEMPTS TO PURGE ALL THE AIR FROM THE LINES.
NOTE 3: DO NOT ATTEMPT TO PERFORM ANY WORK ON THIS BURNER UNLESS THE FOLLOWING TOOLS ARE
AVAILABLE AND YOU ARE A CERTIFIED INSTALLER:
1. Volt meter-volts, ohms, continuity
2. Amp meter-clamp type
3. Burner manual
4. Manometer
5. O
2
or CO
2
analyzer
6. CO tester
7. Blade screw drivers
8. Nut drivers
9. Open end wrenches
10. Tape measure
The Wayne burner that you are troubleshooting has the following electrical single phase components:
1. 120 Volt Combustion Fan Motor with End Switch
2. Fan Relay-24 volt coil side and 120 volt fan side
3. Ignition Control (24 volt)
4. Honeywell Gas Valve (24 volt)
5. Transformer- 120 volt side and 24 volt side
6. Ignition Rod/Sensing Rod
7. Ignition Lead
8. T-T (24 volt) terminal
Summary of Contents for SC80
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