Hitachi RAS-2-HVNP Service Manual page 234

8. Troubleshooting
20
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 code is indicated when the thermistor is short-circuited (less than 1 kΩ) or cut (greater than 6 MΩ) during
the cooling or heating operation.
Phenomenon
Faulty top of compressor
thermistor
Faulty PCB1
The resistance value have fudge factor (+10%).
220
SMGB0079 rev.0 - 01/2013
Abnormality of Thermistor for Discharge Gas Temperature (Compressor Thermistor)
Cause
Fault
Incorrect connection
Check item
Check resistance
Check wiring to PCB1
Replace PCB1 and check
operation
Action
(Turn OFF Main Switch)
Replace thermistor if faulty
Repair wiring and connections
Replace PCB1 if faulty