Hitachi UTOPIA RAS-4HVRP2E - Page 259

10 Troubleshooting
Troubleshooting procedure
SMGB0136 rev.0 - 07/2021
257
10
Alarm code
55
Abnormality of inverter module
• Actual frequency from Inverter PCB is less than 10 Hz (after inverter frequency output form PCB1 to Inverter PCB).
• This alarm is displayed when it occurs 3 times in 30 minutes. Retry operation is performed up to the occurrence of
2 times.
• Condition of Activation:
- This alarm is indicated when Inverter PCB is not performed normally.
• This alarm forces all operations to stop (Outdoor & Indoor Units).
• The unit should be stopped to release the alarm.
Faulty Inverter PCB (DIP-
IPM or ISPM) Replace
it (*2)
Normal
Inverter PCB is normal.
Checkthenoiselter.
If there is no abnormality,
the normal operation can
be performed
Is alarm 55
indicated?
No
Replace inverter PCB
Turn OFF the power, after all LEDS
on PCB are turned OFF, restart the
operation
Yes
? NOTE
When the excessive surge current is applied to the unit due to lighting or other causes, this alarm code or the cause code of inverter stop-
page (Itc=11) will be indicated on the 7-segment display on OU PCB1 and the unit can not be operated. In this case, check to ensure the
surge absorber (SA) on the PCB1. The surge absorber may be damaged if the inner surface of the surge absorber is changed to black. If
thesurgeabsorberisdamaged,replacethenoiselter.Ifthesurgeabsorberdoesnothaveabnormality,turnOFFthepowersourceonce
and wait until turning OFF all LEDS on inverter PCB for approx. 5 min. Then, turn ON again.