Hitachi RAS-5HVRNM1E Service Manual page 279

8 Troubleshooting
54
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.
– If the alarm code "51" or "54" occurs three times within 30 minutes, the alarm code which occurred for the third time
is displayed. The retry operation is performed twice.
Conditions:
• When the temperature of the thermistor for inverter fin excess 100 °C (RAS-(4-12)HRNM(1)(E), 80 °C (RAS-
(3-6)HVRNM(1)E) 3 times in 30 minutes, this alarm is indicated and the operation is stopped. In the case the occurrence
is smaller than 2 times, retry is performed.
Restart the operation.
Does it trip soon?
No
Is the heat exchanger of the
outdoor unit clogged?
No
N O T E
• 1*): Perform the high voltage discharge work by referring to the item
for ES Series, see on page 312 before checking and replacing the inverter components.
271
SMGB0060 rev. 1- 12/2010
Increase in the inverter fin temperature IVX Series
Yes
Is thermistor short circuit or
faulty?
Yes
Yes
No
Replace the dipIPM, ISPM,
IPM. *1
Replace the thermistor
Remove the clogging
Faulty PCB2 or thermistor.
Replace it.
Procedure of checking other main parts
8