Lennox EL296UHVX Series Unit Information page 41

B- Indoor Blower Motor
Power Choke
Blower Motor
(4 and 5 Ton Only)
To Remove Blower From Unit: Remove access panels,
Control box, Bolts and Wiring Jackplugs.
Then Slide Out Front of Unit.
FIGURE 6
Blower Drive -045
Some EL296UHV units will be equipped with a blower drive
shown in figure 7 with LED codes for operation in table14.
The blower drive is not repairable. If it fails replace the
drive,.
BLOWER DRIVE
Located in the control box
Three pin connector to
blower motor
FIGURE 7
(B3)
Led*
1 Short Blink
2 Short Blinks
3 Short Blinks
4 Short Blinks
5 Short Blinks
1 Long Blink + 1 Short Blink
1 Long Blink + 2 Short Blinks
1 Long Blink + 3 Short Blinks
* Do not touch or remove drive for replacement until all blinking lights
are off. Blinking light(s) indicates drive still has power.
During blower operation, the ECM motor emits ener­
gy that may interfere with pacemaker operation. In­
terference is reduced by both the sheet metal cabinet
and distance.
The motor communicates with the integrated control via a
2-way serial connection. The motor receives all necessary
functional parameters from the integrated control and does
not rely on a factory program like traditional variable speed
motors. EL296UHV units use a three‐phase, electronically
controlled D.C. brushless motor (controller converts single
phase a.c. to three phase D.C.), with a permanent‐magnet‐
type rotor (figure 8). Because this motor has a permanent
magnet rotor it does not need brushes like conventional D.C.
motors.
The stator windings are split into three poles which are electri­
cally connected to the controller. This arrangement allows
motor windings to turn on and off in sequence by the con­
troller.
Earlier ECM motors used on other Lennox furnace
models are not interchangeable with motors used on
the EL296UH furnace line.
A solid‐state controller is permanently attached to the
motor. The controller is primarily an A.C. to D.C. con­
verter. Converted D.C. power is used to drive the motor.
The controller contains a microprocessor which moni­
tors varying conditions inside the motor (such as motor
workload).
BLOWER MOTOR COMPONENTS
STATOR
(WINDINGS)
BEARING
Page 41
TABLE 14
Blower Drive LEDs
Meaning
Normal heartbeat
Drive fault
(replace drive)
Temporary fault
(see troubleshooting
Page 44)
WARNING
IMPORTANT
ROTOR
FIGURE 8