Hitachi RAS-H(V)RNME-AF Service Manual page 348

12 Troubleshooting
04
Alarm code
• 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 displayed when the abnormal operation is maintained for 30 seconds after the normal transmission
between the outdoor unit PCB1 and inverter PCB2. Also, the abnormal operation is maintained for 30 seconds
after the micro-computer is automatically reset. The alarm is displayed when the abnormal transmission is main-
tained for 30 seconds from the starting of the outdoor unit.
Is power fuse for
outdoor unit (EF1 or
EF2) normal?
Yes
Turn ON the power supply
Is LED2 (green)
on PCB2 ON/OFF
flashing?
PCB2 is normal?
PCB1: Inverter PCB
Inverter DIP IPM RAS-(3-6)HVRNME-AF
Inverter ISPM RAS-(4-6)HRNME-AF
338
SMGB0070 rev. 1 - 08/2011
Abnormal transmission between inverter PCB2 and outdoor PCB1
(RAS-(3-6)H(V)RNME-AF)
No
LED2 is ON or OFF
Flashing
Replace fuse if blown
N O T E
Investigate the cause of fuse blown
Faulty PCB2 or faulty
DC fan motor