Code Description Severity Self-Clear Latching Shutdown Shutdown
Detail:
Reading from secondary filter inlet pressure sensor PS5b (Pump 2 outlet) is outside the normal range of -1 to 8 bar (-15 to 116 psi) and
min/max values only will be displayed.
Action: Check sensor connections to the control board, check inline connections, replace sensor.
A17
Secondary Flow Meter Sensor
Fault
2
ü
— — —
Detail: Secondary flow meter output is below 4mA.
Action: Check sensor connections to the control board, check inline connections, replace sensor.
A18* Primary Flow Meter Sensor Fault 3
ü
— — —
Detail: Primary flow meter output is below 4mA.
Action: Check sensor connections to the control board, check inline connections, replace sensor.
A19 MicroSD Card Fault 3
ü
— — —
Detail: The SD card has either been removed or physically damaged.
Action: Replace the SD card.
A20 Pump P1 Inverter Fault 2
ü
— — —
Detail:
Pump 1 is drawing excessive current, or inverter has been subjected to over/under voltage. Alarm will only appear after inverter has gone
into fault condition a second time (default), after first attempting a fault reset. Pump 1 will then run.
Action: Note any fault code on the inverter display and contact Vertiv for more information/corrective action.
A21
Pump P1 Inverter
Communications Fault
2 — — — —
Detail: Controller unable to communicate with pump Inverter 1,
Action: Check wiring and terminations,
A22 Pump 1 Low Flow 2 —
ü
— —
Detail: Pump 1 has not reached the flow rate (or differential pressure) setpoint in the specified time limit (default 100 secs).
Action:
Check that unit has been set for the correct system flow rate (or DP), check for system blockages, check inverter drive for faults, check
non-return valves on Pumps are not sticking open (Pump rotating slowly backwards). Reduce flow setting (or DP).
A23 Pump P2 Inverter Fault 2 —
ü
— —
Detail:
Pump 2 is drawing excessive current, or inverter has been subjected to over/under voltage. Alarm will only appear after inverter has gone
into fault condition a second time (default), after first attempting a fault reset. Pump 2 will then run.
Action: Note any fault code on the inverter display and contact Vertiv for more information/corrective action.
A24
Pump P2 Inverter
Communications Fault
2 —
ü
— —
Detail: Controller unable to communicate with pump Inverter 2.
Action: Check wiring and terminations.
A25 Pump 2 Low Flow 2 —
ü
— —
Detail: Pump 2 has not reached the flow rate (or differential pressure) setpoint in the specified time limit (default 100 secs).
Action:
Check that unit has been set for the correct system flow rate (or DP), check for system blockages, check inverter drive for faults, check
Table 4.41 Alarm Identification and Severity Level (continued)
54 Proprietary and Confidential ©2025 Vertiv Group Corp. 4 Operation
Vertiv™ CoolChip CDU 600 Operation and Maintenance Guide
To Next Page
Loading...
