Hitachi UTOPIA RAS-4HVRP2E Service Manual page 269

10 Troubleshooting
Troubleshooting procedure
06
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 either insufficient voltage or overvoltage is detected between the terminal R-S on the inverter PCB (Driver Board)
three times in 30 minutes, the operation stops and this alarm code is displayed. If this occurs less than three times in
30 minutes, the operation is automatically retried.
Start Operation
Yes
Is the power supply voltage within the
range of ± 10% of the rated voltage?
Yes
Is the power supply voltage higher
than 85% of the rated voltage during
operation?
Yes
Is there any other high-power
equipment start during the
operation? Is the power voltage
higher than 85% of the rated
voltage?
Yes
Is the power indicator is light on
when the main relay indicator is ON?
Yes
267 SMGB0136 rev.0 - 07/2021
Abnormal Inverter voltage (Insufficient inverter voltage or over voltage)
No
No
No
No
Check if the wiring of reactor is loose?
No
Replace the damaged driver board or fan
motor driver board if faulty
Check the power supply voltage and
remove the fault to avoid the voltage
too low or too high
Yes
Fasten the wiring
10