Code Description Severity Self-Clear Latching Shutdown Shutdown
---- No Display —
ü
— — —
Detail: Display not illuminated. Power failure on display board or controller I/O board.
Action:
Open upper electrical panel door to check that 24V DC is available at controller I/O board. If there are no LEDs showing on processor board,
then check I/O board 24V fuse FS1. If LEDs are on, check for wiring faults between I/O board and display.
A01
T1 Primary Temperature Sensor
Fault
3
ü
— — —
Detail: Reading from primary temperature sensor T1 is outside the normal range of -5C° to 74°C (23°F to 165°F) or disconnected.
Action: Check sensor connections to control board, check inline connections, replace sensor.
A02
T2a Secondary Temperature
Sensor Fault
3
ü
— — —
Detail: Reading from secondary supply temperature sensor T2a is outside the normal range of 5 to 74°C (41 to 165°F) or disconnected.
Action: Check sensor connections to the control board, check inline connections, replace sensor.
A03
T2b Secondary Temperature
Sensor Fault
3 — — — —
Detail: Reading from secondary supply temperature sensor T2b is outside the normal range of 5 to 74°C (41 to 165°F) or disconnected.
Action: Check sensor connections to the control board, check inline connections, replace sensor.
A04
T2c Secondary Temperature
Sensor Fault
3 — — — —
Detail: Reading from fluid supply temperature sensor T3b is outside the normal range of 5 to 74°C (41 to 165°F), or disconnected.
Action: Check sensor connections to the control board, check inline connections, replace sensor.
A05
T3 Room Temperature Sensor
Fault
3
ü
— — —
Detail: Reading from Room temperature sensor T3 is outside the normal range of 5 to 70°C (41 to 158°F), or disconnected.
Action: Check sensor connections to the control board, check in-line connections, replace sensor.
A06
T4 Secondary Temperature
Sensor Fault
3
ü
— — —
Detail: Reading from Secondary return temperature sensor T4 is outside the normal range of 5 to 70°C (41 to 158°F), or disconnected.
Action:
A07
T5 Primary Temperature Sensor
Fault
3
ü
— — —
Detail: Reading from Primary return temperature sensor T4 is outside the normal range of 5 to 70°C (41 to 158°F), or disconnected.
Action: Check sensor connections to the control board, check inline connections, replace sensor.
A08
RH Relative Humidity Sensor
Fault
3
ü
— — —
Detail:
Reading from Room humidity sensor RH is outside the normal range of 5 to 100% RH or disconnected. Note: if in Fixed Setpoint + DW
Offset mode, unit will revert to Fixed Setpoint mode – default 18°C (65°F).
Action: Check sensor connections to the control board, check inline connections, replace sensor.
Table 4.41 Alarm Identification and Severity Level
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Vertiv™ CoolChip CDU 600 Operation and Maintenance Guide
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