Hitachi UTOPIA RAS-4HVRP2E Service Manual page 289

10 Troubleshooting
Troubleshooting procedure
48
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 instantaneous overcurrent or electronic thermal protection occurs on inverter as follows, the compressor stops. The
operation automatically restarts after three minutes. If this occurs again five times in the next 30 minutes, this alarm code
is displayed.
Condition of Activation:
1 Instantaneous overcurrent
Main causes: Compressor damage, output U, V, W are connected in reverse.
2 Electronic thermal
Main causes: Heavy compressor load, and so on.
3 PFC_A hardware overcurrent
Main causes: Short circuited PFC electric reactor L1, driver hardware is abnormal.
4 PFC_B hardware overcurrent
Main causes: Short circuited PFC electric reactor L2, driver hardware is abnormal.
5 AC input overcurrent
Main causes: AC input voltage under voltage, higher compressor load, and so on.
6 AC input overload
Main causes: AC input voltage overload, higher compressor load, and so on.
287 SMGB0136 rev.0 - 07/2021
Activation of Inverter Overcurrent Protection
10