Lennox EL280DFE Series

Page 19
To Measure Flame Signal - Integrated Control:
Use a digital readout meter capable of reading DC micro
amps. See figure 15 and table 9 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.
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 9
Flame Signal in Microamps
Normal
Low Drop Out
2.6 or greater 2.5 or less .06
FIGURE 15
Measuring Flame Signal
(upflow furnace shown)
Set dial to measure
DC microamps
(+)
To Flame
Terminal
DIGITAL METER
Red Collar
Indicates
Positive Leads
(+) To Control
Sensor Terminal
Flame
Sensor
Flame Sensor
Wire
Integrated
Control
Remove Sensor Wire from
Integrated Control and
Connect Alligator Clip (−)
to Frame Sensor Lead
Flame Sensor
Terminal
Remove Sensor Wire from
Integrated Control and
Connect Alligator Clip (+)
to Terminal on Control
(+)