Lennox EL280DF Series Unit Information page 13

To Measure Flame Signal - Integrated Control:
Use a digital readout meter capable of reading DC micro­
amps. See figure 9 and table 5 for flame signal check.
1 - Set the meter to the DC amps scale.
2 - Turn off supply voltage to control.
3 - Disconnect integrated control flame sensor wire from
the flame sensor.
4 - Connect (-) lead to flame sensor.
5 - Connect (+) lead to the ignition control sensor wire.
Flame
Sensor
Flame Sensor
Wire
Measuring Flame Signal
(upflow furnace shown)
Integrated
Control
(+)
Remove Sensor Wire from
Integrated Control and
Connect Alligator Clip (+)
to Terminal on Control
FIGURE 9
Page 13
6 - Turn supply voltage on and close thermostat contacts
to cycle system.
7 - When main burners are in operation for two minutes,
take reading.
TABLE 5
Flame Signal in Microamps
Normal
1.9 or greater 1.4 or less
Remove Sensor Wire from
Integrated Control and
Connect Alligator Clip (−)
to Frame Sensor Lead
Flame Sensor
Terminal
(+) To Control
Sensor Terminal
Low Drop Out
.20
DIGITAL METER
Set dial to measure
DC microamps
Red Collar
(+)
Indicates
Positive Leads
To Flame
Terminal