Hitachi RWM-(H)FSN3E, Service Manual

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12 Troubleshooting
SMGB0070 rev. 1 - 08/2011
384
Alarm code
54
Increase in the inverter fin temperature
• 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 ºC (RAS-(3-6)HVRNME-AF), 80 ºC (RAS-(4-10)
HRNME-AF) 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.
No
Replace the dipIPM, ISPM,
IPM. *1
No
Replace the thermistor
Remove the clogging
Is the heat exchanger of the
outdoor unit clogged?
Faulty PCB2 or thermistor.
Replace it.
No
Yes
Restart the operation.
Does it trip soon?
Is thermistor
short circuit or
faulty?
Yes
Yes
*1) Perform the high voltage discharge work by referring to the item Procedure of checking other main parts before chec-
king and replacing the inverter components.