Figure 44 Control Disassembly; Figure 45 Winding Test; Figure 46 Drip Loop - Bard QW2S3DA Installation Instructions Manual

Replacing ECM Control Module
To replace the control module for the GE variable-speed indoor
blower motor you need to take the following steps:
1. You MUST have the correct replacement module. The
controls are factory programmed for specific operating modes.
Even though they look alike, different modules may have
completely different functionality.
USING THE WRONG CONTROL MODULE VOIDS ALL PRODUCT
WARRANTIES AND MAY PRODUCE UNEXPECTED RESULTS.
2. Begin by removing AC power from the unit being serviced. DO
NOT WORK ON THE MOTOR WITH AC POWER APPLIED. To
avoid electric shock from the motor's capacitors, disconnect
power and wait at least 5 minutes before opening motor.
3. It is not necessary to remove the motor from the blower
assembly, nor the blower assembly from the unit. Unplug the
two cable connectors to the motor control assembly. There
are latches on each connector. DO NOT PULL ON THE
WIRES. The plugs remove easily when properly released.
4. Locate the screws that retain to the motor control bracket
to the sheet metal of the unit and remove them. Remove
two (2) nuts that retain the control to the bracket and then
remove two (2) nuts that retain sheet metal motor control
end plate. Refer to Figure 44.
5. Disconnect the three (3) wires interior of the motor control
by using your thumb and forefinger squeezing the latch tab
and the opposite side of the connector plug, gently pulling
the connector. DO NOT PULL ON THE WIRES, GRIP THE
PLUG ONLY. Refer to Figure 45.
6. The control module is now completely detached from the
motor. Verify with a standard ohmmeter that the resistance
from each motor lead (in the motor plug just removed)
to the motor shell is >100K ohms. Refer to Figure 45.
(Measure to unpainted motor end plate.) If any motor lead
fails this test, do not proceed to install the control module.
THE MOTOR IS DEFECTIVE AND MUST BE REPLACED.
Installing the new control module will cause it to fail also.
7. Verify that the replacement control is correct for your
application. Refer to the manufacturer's authorized
Only remove
Hex Head Bolts
ECM 2.0
Note:
Use the shorter
bolts and
alignment pin
supplied when
replacing an
ECM 2.0
control.
Manual 2100-738C
Page 70 of 73
Figure 6
Figure 44
Figure 3
Control Disassembly
From Motor
Push until
Latch Seats
Over Ramp
Circuit
Board
Motor
Motor Connector
(3-pin)
ECM
ECM 5.0
Control Connector
2.3/2.5
(16-pin)
Power Connector
(5-pin)
Hex-head Screws
replacement list. USING THE WRONG CONTROL WILL
RESULT IN IMPROPER OR NO BLOWER OPERATION.
Orient the control module so that the 3-wire motor plug
can be inserted into the socket in the control. Carefully
insert the plug and press it into the socket until it latches.
A SLIGHT CLICK WILL BE HEARD WHEN PROPERLY
INSERTED.
8. Reverse the steps #5, 4, 3 to reconnect the motor
control to the motor wires, securing the motor control
cover plate, mounting the control to the bracket, and
mounting the motor control bracket back into the unit.
MAKE SURE THE ORIENTATION YOU SELECT FOR
REPLACING THE CONTROL ASSURES THE CONTROL'S
CABLE CONNECTORS WILL BE LOCATED DOWNWARD
IN THE APPLICATION SO THAT WATER CANNOT RUN
DOWN THE CABLES AND INTO THE CONTROL. DO NOT
OVERTIGHTEN THE BOLTS.
9. Plug the 16-pin control plug into the motor. The plug is
keyed. Make sure the connector is properly seated and
latched.
10. Plug the 5-pin power connector into the motor. Even
though the plug is keyed, OBSERVE THE PROPER
ORIENTATION. DO NOT FORCE THE CONNECTOR. It
plugs in very easily when properly oriented. REVERSING
THIS PLUG WILL CAUSE IMMEDIATE FAILURE OF THE
CONTROL MODULE.
11. Final installation check. Make sure the motor is installed as
follows:
a. Motor connectors should be oriented between the 4
o'clock and 8 o'clock positions when the control is
positioned in its final location and orientation.
b. Add a drip loop to the cables so that water cannot enter
the motor by draining down the cables. Refer to Figure
46.
The installation is now complete. Reapply the AC power to the
HVAC equipment and verify that the new motor control module
is working properly. Follow the manufacturer's procedures for
disposition of the old control module.
Figure 7
Figure 45
Figure 4
Winding Test
Motor Connector
(3-pin)
Motor OK when
R > 100k ohm
Figure 8
Figure 46
Figure 5
Drip Loop
Connector Orientation
Back of
Control
Between 4 and 8 o'clock
Drip Loop