Johnson Controls P Series Installation And Maintenance Manual page 23

2. Malfunction of Blocked Protection of IDU Fan Motor H6
Main detection points:
● Is the control terminal of PG motor connected tightly?
● Is the feedback interface of PG motor connected tightly?
● The fan motor can't operate?
● The motor is broken?
● Detection circuit of the mainboard is defined abnormal?
Malfunction diagnosis process:
Test whether the voltage between terminal 1 and terminal 2
Installation and Maintenance
Start
Turn the fan blades
by hand under
power-off condition
Whether the fan blades
can run smoothly?
Yes
Under power-off condition,
check whether the wiring terminal
between indoor fan and main
board is loose.
No
Connect power and restart the unit.
of motor interface is within 280~310VDC.
Yes
Then check whether the voltage
between terminal 2 and terminal 3
of the motor interface is 15VDC.
Yes
Then check whether there is voltage
between terminal 2 and terminal 4
of the motor interface.
Yes
It's the malfunction of motor.
Replace a new motor that is
of the same model.
Adjust the motor and blade
assembly so that rotor can run
No
smoothly.
No
Yes
to check whether the
No
It's the malfunction of main board.
No
Replace a new main board that is
of the same model.
It's the malfunction of main board.
No
Replace a new main board that is
of the same model.
It's the malfunction of main board.
No
Replace a new main board that is
of the same model.
Turn unit on
to check whether the
malfunction is
eliminated.
Reinsert the wiring
terminal of indoor fan.
Turn unit on
Yes
malfunction is
eliminated.
End
Yes
14