Hitachi RCUE40AG2 Service Manual page 120

Troubleshooting

Alarm code

[Alarm Stop Reason]
- Refrigerant temperature in water side heat
exchanger inlet (Tr) is less than –6.5°C during 3
seconds. (only for cooling operation)
*Alarm stop: 3 retries during 30 minutes.
(Compressor stop, automatic restart in 3 minutes)
- Refrigerant temperature in water side heat
exchanger inlet (Tr) is less than -35°C during 10
seconds. (only for defrosting operation)
- If the time between the end of a defrost, and
the confi rmation of the conditions to start again a
defrost in the same cycle is less then 13 minutes.
*No retry during defrosting operation. Alarm stop
immediately.
Is the wiring of connector
in the Printed Circuit Board
for Relay (PCB ) correct?
D
Yes
Pull out connector and
measure thermistor
resistance. Is resistance
correct?
Yes
Yes
Check Printed Circuit
Board for Relay
(PCB )
D
pag. 118
SMGB0003 rev.0 - 01/2007
Excess Low Temperature of Cooler Inlet Refrigerant (Tr)
No
No
[PCB Monitoring Position]
No. 1 Cycle: PCB
D1
No. 2 Cycle: PCB
D2
No. 3 Cycle: PCB
D3
No. 4 Cycle: PCB
D4
No. 5 Cycle: PCB
D5
[Retry Code]
No. 1 Cycle: C1-P6
No. 2 Cycle: C2-P6
No. 3 Cycle: C3-P6
No. 4 Cycle: C4-P6
No. 5 Cycle: C5-P6
Plug correctly and
repair wiring
Replace thermistor
Check the water fl ow rate.(Check
temperature of inlet and outlet.)
Clogging of water strainer
Pump reverse rotating check
Check the air mixing
Check chilled water thermostat setting value
(Within the working range)
Shortage of refrigerant / Gas leakage
Clogging of low pressure pipe
Clogging of expansion valve
Malfunction of check valve
Malfunction of expansion valve
(I/O PCB) CN27Tr2
(I/O PCB) CN27Tr2
(I/O PCB) CN27Tr2
(I/O PCB) CN27Tr2
(I/O PCB) CN27Tr2