Hitachi UTOPIA RAS-4HVRP2E Service Manual page 297

10 Troubleshooting
Troubleshooting procedure
57
Alarm code
• The alarm code is flashed on the 7-segment display of the outdoor unit.
• The alarm code is displayed on the wired controller of the indoor unit.
If the revolution of the fan motor is less than 10rpm in 10 seconds after the fan motor starts operation, the fan motor
stops. The fan motor restarts operation automatically after 10 seconds (During this, the compressor continues to
operate). If this occurs again nine times in the next five minutes, this alarm code is displayed. This alarm is caused by
locking or electrical abnormality of the fan motor.
Restart operation
Yes
Does fan motor run when
inverter failure occurs?
Yes
Is the power supply voltage higher
than 85% of the rated voltage during
operation?
Yes
Turn OFF power supply and check if
the fan blade rotates smoothly
Yes
Fan motor damaged, replace fan motor
295 SMGB0136 rev.0 - 07/2021
Abnormality of Fan Motor
Turn OFF outdoor
unit power supply and
disconnect compressor
No
and fan motor wiring.
Short circuit TCN10 (FCT)
connector.
Does it fail?
No
No
No
Check fan
motor if wiring
is normal
No
Yes
Check the power supply voltage, remove
the fault to avoid the voltage too low or
Check if there are any obstacles.
Replace the fan motor if it is damaged.
Yes
Replace driver
of fan motor
Replace fan
motor
Replace driver
of fan motor
too high
10