Electrical Checks - Low Voltage Control Circuits; Motor Control/End Bell Checks - Daikin ComfortNet DX16TC Series Service Instructions Manual

SERVICING
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1
Lines 1 and 2 will be connected
for 12OVAC Power Connector
2
applications only
3
Gnd
4
AC Line Connection
5
AC Line Connection
5. Measure voltage between pins 4 and 3. Voltage should be
approximately half of the voltage measured in step 4.
6. Measure voltage between pins 5 and 3. Voltage should be
approximately half of the voltage measured in step 4.
7. If no voltage is present, check supply voltage to air handler
or modular blower. See section S-1.
8. Disconnect power to air handler or modular blower. Re-
connect the 5-circuit power harness disconnected in step
2.

Electrical Checks - Low Voltage Control Circuits

1. Turn on power to air handler or modular.
WARNING
Line Voltage now present.
2. Check voltage between pins on the 4-wire motor control
harness between themotor and control board.
3. Voltage on pins should read:
Pins 1 to 4 = 3.3vdc
Pins 1 to 2 = 3.3vdc
Pins 3 to 4 = 15vdc

Motor Control/End Bell Checks

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 air handler or modular blower.
NOTE: Motor contains capacitors that can hold a charge for
several minutes after disconnecting power. Wait 5 minutes
after removing power to allow capacitors to discharge.
2. Disconnect the motor control harness and motor power
harness.
3. Remove the blower assembly from the air handler or
modular blower.
4. Remove the (3) screws securing the control/end bell to
the motor. Separate the control/end bell. Disconnect the
3-circuit harness from the control/end bell to remove the
control/end bell from the motor.
5. Inspect the NTC thermistor inside the control/end bell (see
figure below). Replace control/end bell if thermistor is
cracked or broken.
6. Inspect the large capacitors inside the control/end bell (see
figure below). Replace the control/end bell if any of the
capacitors are bulging or swollen.
7. Locate the 3-circuit connector in the control/end bell.
Using an ohmmeter, check the resistance between each
terminal in the connector. If the resistance is 100 W or
greater, the control/end bell is functioning properly. Re-
place the control/end bell if the resistance is lower than
100 W.
8. Reassemble motor and control/end bell in reverse of
disassembly. Replace blower assembly into air handler or
modular blower.
Motor Checks
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.
72