Alarm Indication - Hitachi SAMURAI Series Service Manual

4 Troubleshooting
Alarm indication

4.5 Alarm indication

In case of occurrence of sensor abnormalities while the chiller unit is stopped, or of abnormalities that would not trigger
an alarm stop, a warning is output to the outside and warning display is conducted. The mark
Screen during warning external output.
The content of warning is shown in the table below.
Warning indication
Freeze prevention
Inlet water temperature thermistor
abnormality (CN4)
Outlet water temperature thermistor
abnormality (CN5)
Cooler inlet thermistor abnormality (CN29)
Discharge gas thermistor abnormality
(CN26)
Liquid temp thermistor abnormality (CN24)
Outlet rear side thermistor abnormality
(CN25)
Suction gas thermistor abnormality (CN27)
Discharge pressure sensor abnormality
(CN31)
Suction pressure sensor abnormality
(CN32)
Water supply header thermistor
abnormality (CN13)
Water return header thermistor
abnormality (CN14)
CPU-I/O Transmission
COMP Run/Stop Frequency
Transmission of Control of Master/Slave
group
Incorrect Setting of Control of Master/
Slave group
Insufficient number of operable units
Overhaul Period
I/O internal transmission
*1. It becomes an alarm when compressor is in operation.
*2. It becomes an alarm when the chiller unit is put to operation while in alarm output status.
*3. The spanner mark disappears when operating time period of the compressor is changed to less than 40000 hours. Warning display is
automatically released when the abnormal condition is cleared.
93 SMGB0120 rev.0 - 11/2017
Warning icon is
shown
Caution is
illuminated
Contents of warning
Water temperature is 1ºC or below
Disconnection or short-circuit of the inlet water
temperature thermistor
Disconnection or short-circuit of the outlet water
temperature thermistor
Disconnection or short-circuit of the cooler inlet
(evaporating temperature) thermistor
Disconnection or short-circuit of the discharge gas
thermistor
Disconnection or short-circuit of the liquid
temperature thermistor
Disconnection or short-circuit of the (rear side)
outlet water temperature thermistor
Disconnection or short-circuit of the suction gas
thermistor
Disconnection or short-circuit of the high pressure
sensor
Disconnection or short-circuit of the low pressure
sensor
Disconnection or short-circuit of the water supply
header thermistor
Disconnection or short-circuit of the water return
header thermistor
Transmission abnormality between CPU-I/O PCBs When the chiller unit is stopped *2
Frequency of compressor run/stop higher than 6
times/hour
Transmission abnormality between Unit No.1 and
Unit No.2 and the following
Incorrect setting of DIP Switch / Rotary Switch
Number of operable chiller units < Setting value of
minimum number of operating units
Operating time period of compressor higher than
40000 hours *3
CO072 (I/O PCB) Abnormality
is shown on the LCD
Spanner mark
Warning
contents display
Yellow during
occurrence of warning
Notes
When compressor is stopped while
the chiller unit is in operation *1
When the chiller unit is stopped *2
When the chiller unit is stopped *2
When the chiller unit is stopped *2
When the chiller unit is stopped *2
When the chiller unit is stopped *2
When the chiller unit is stopped *2
When the chiller unit is stopped *2
When the chiller unit is stopped *2
When the chiller unit is stopped *2
When using the function to control
the number of units / When system
is stopped (in 2-pump system I or II)
When using the function to control
the number of units / When system
is stopped *2
When using the function to control
the number of units / When system
is stopped *2
When using the function to control
the number of units
Warning mark is not displayed.
Spanner mark is displayed
When chiller unit is stopped *2
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