Intertek ACVC96 Service Instructions Manual page 63

SERVICING
6. Ensure motor and wheel turn freely. Check for interfer-
ence between wheel and housing or wheel and motor.
Repair or replace as needed.
7. Check housing for cracks and/or corrosion. Repair or
replace as needed.
8. Check motor mounting bracket. Ensure mouting bracket
is tightly secured to the housing. Ensure bracket is not
cracked or broken.
UltraCheck-EZ TM Diagnostic Tool
The UltraCheck-EZ TM diaganostic tool is the preferred method
(part # UTT-01) to diagnose the ECM motor.
HIGH VOLTAGE!
Disconnect ALL power before servicing
or installing. Multiple power sources
may be present. Failure to do so may
cause property damage, personal injury
or death.
To use the diagnostic tool, perform the following steps:
1. Disconnect power to the furnace.
2. Disconnect the 4-circuit control harness from the motor.
3. Plug the 4-circuit connector from the diagnostic tool into
the motor control connector.
4. Connect one alligator clip from the diagnostic tool to a
ground source.
5. Connect the other alligator clip to a 24VAC source.
NOTE: The alligator clips are NOT polarized.
NOTE: The UltraCheck-EZ
with a nonreplaceable fuse. Connecting the tool to a source
other than 24VAC could damage the tool and cause the
fuse to open. Doing so will render the diagnostic tool inop-
erable.
6. Turn on power to the furnace.
WARNING
Line Voltage now present.
7. Depress the orange power button on the diagnostic tool
to send a run signal to the motor. Allow up to 5 seconds
for the motor to start.
NOTE: If the orange power button does not illuminate when
depressed, the tool either has an open fuse or is not prop-
erly connected to a 24VAC source.
8. The green LED on the diagnostic tool will blink indicating
communications between the tool and motor. See table
below for indications of tool indicators and motor actions.
TM
diagnostic tool is equipped
Replace or repair as needed.
P o w e r G re e n M o tor
Bu tto n LED Actio n
O FF O F F
Rotating
O N B link ing Rotating
O N O F F Rotating
O N B link ing
Rotating
O N O F F
Rotating
9. Depress the orange power button to turn off motor.
10. Disconnect power. Disconnect diagnostic tool.
11. Reconnect the 4-wire harness from control board to
motor.
Electrical Checks - High Voltage Power Circuits
HIGH VOLTAGE!
Disconnect ALL power before servicing
or installing. Multiple power sources
may be present. Failure to do so may
cause property damage, personal injury
or death.
1. Disconnect power to the furnace.
2. Disconnect the 5-circuit power connector to the ECM
motor.
3. Turn on power to the furnace.
WARNING
Line Voltage now present.
4. Measure voltage between pins 4 and 5 on the 5-circuit
connector. Measured voltage should be the same as the
supply voltage to the furnace.
In d ica tio n (s)
Confirm 24V A C to
TM
UltraChec k -E Z tool.
Not
If 24V A C is c onfirm ed,
diagnos tic tool is
inoperable.
M otor and c ontrol/end
bell are func tioning
properly .
Replac e m otor
c ontrol/end bell.
Not Chec k m otor (s ee
Motor Chec k s below).
Replac e m otor
Not c ontrol/end bell; verify
m otor (s ee Motor
Chec k s below).
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