Hitachi RAS-10HRNM, Service Manual, Page: 285 / 482

Alarm code
57
Abnormality of fan motor protection (DC fan motor) for IVX series
• The RUN LED flickers and “ALARM” is displayed on the remote control switch.
• The unit number, the alarm code and the unit code are alternately displayed on the set temperature section. The unit
number and the alarm code are displayed on the display of the outdoor unit PCB.
– This alarm is indicated when the revolution pulse output from the fan motor is 10 rpm or less and the reverse
revolution signal is detected. The fan motor is stopped once, and restarted after 10 seconds.
If it occurs more than 10 times in 30 minutes, this alarm is indicated. The abnormality occurs when the fan motor is
stopped.
Yes
This alarm is indicated due
to detected overcurrent by
the contrary wind. This is
normal.
Does the motor run?
Remove the foreign matter.
Does the fan stop by the foreign
matter?
Check to remove the connector connection of CN15 (on PCB1)
and CN201, CN202, PCN201, PCN203 (on PCB5).
Faulty
Restart operation
No
Alarm code is not indicated
Yes
No
Are the connectors abnormal?
Connect it correctly.
Restart operation
Does the motor run?
This is normal
Replace the fan motor
Restart operation
Does the motor run?
Yes
Good
This is normal
Yes
No
Alarm code is not indicated
Replace the PCB1
No
N O T E
• In the case that the fan motor does not run even the PCB1 is replaced, replace PCB5.
• Check to ensure that DC Fan Motor is checked according to the item Procedure of checking other main parts
for ES Series , see on page 312.
8 Troubleshooting
277
SMGB0060 rev. 1- 12/2010
8