Hitachi SAMURAI Series Service Manual page 110

4. Troubleshooting
Troubleshooting by alarm code
C1-91
Alarm code
Alarm stop reason
Inlet refrigerant temperature of the heat exchanger (Te) becomes lower than -6.5ºC for more than 3 seconds. (only enabled
in cooling).
N O T E
Causes alarm stop with 3 occurrences in 30 minutes. Retry control is performed until the second one. (Compressor
stops, and restarts automatically after 3 minutes)
Inlet refrigerant temperature of the heat exchanger (Tr) becomes lower than -35ºC for more than 10 seconds. (only enabled
in defrosting)
N O T E
Retry is not performed during during defrosting.
Retry indication
LCD: By touching "Inspection", "Cooler Inlet Retry" is shown in "No.1 Cycle".
Retry code
C1-P6
PCB monitoring position
PCBd (I/O PCB) CN29 (Cooler inlet thermistor)
Cooler inlet
refrigerant temperature
has actually dropped to the
activation value
No
The connection and
insertion of connector
CN29 on PCB (I/O PCB)
d
are correct
Yes
There are
problems with thermistor
characteristics
No (There are no problems)
Check of PCB (I/O PCB)
d
103
SMGB0097 rev.0 - 07/2015
Cooler Inlet Decrease
Yes
No
Correction of
connections
Yes (There are problems)
Replace thermistor
Adjustment of water quantity (adjustment
of inlet-outlet water temperature)
Clogging of water strainer
Adjustment of reverse rotation of pump
Adjustment of cold water thermo settings.
Shall be within usage range
Lack of refrigerant. Gas leakage
Clogging of low pressure side pipes
Clogging of expansion valve
Malfunction of check valve
Malfunction of expansion valve
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