Unit installation

CDU Installation Guide Page 43
Cooling Distribution Unit
TROUBLESHOOTING (continued).
Code: a03 – ‘Sec temp T2a out of range’ (self clear)
Reading from secondary temperature sensor T2a is outside the nominated range of -
31°C to +66°C (-23.8°F to +150.8°F).
Action: Check sensor connections to the control board.
Code: a04 – ‘Room temp out of range’ (self clear)
Reading from room temperature sensor T3 is outside the nominated range of -31°C to
+66°C (-23.8°F to +150.8°F).
Action: Check sensor connections to the control board.
Code: a05 – ‘Sec pump LP out of range’ (self clear)
Reading from pressure sensor PS1 is outside the nominated range of -1 to 8Bar (-14.4
to 116PSI).
Action: Check sensor connections to the control board.
Code: a06 – ‘Sec pump HP out of range’ (self clear)
Reading from pressure sensor PS2 is outside the nominated range of -1 to 8Bar (-14.4
to 116PSI).
Action: Check sensor connections to the control board.
Code: a07 – ‘Prim LP out of range’ (self clear)
Reading from pressure sensor PS4 is outside the nominated range of -1 to 8Bar (-14.4
to 116PSI).
Action: Check sensor connections to the control board.
Code: a08 – ‘Prim HP out of range’ (self clear)
Reading from pressure sensor PS3 is outside the nominated range of -1 to 8Bar (-14.4
to 116PSI).
Action: Check sensor connections to the control board.
Code: a10 – ‘Insufficient water level’ (engineer to clear)
Insufficient level in the reservoir after fill pump has been running for 3 minutes (in
automatic mode).
Action: Check that filling wand is fully immersed in water container to pump into the
system. Check the system for leaks.
Code: a11 – ‘Pump P1 inverter fault’ (engineer to clear)
Pump P1 is drawing excessive current, or inverter has been subjected to excessive
voltage. Alarm will cancel when inverter receives a reset signal (controller will pulse a
reset to inverter on new pump start signal after fault received).
Action: Force Pump 1 to run using ‘Manual Control’ function and measure current
drawn by pump. If higher than setting in the inverter (see page 19), then pump
should be replaced. If current is OK, then replace inverter drive unit.
Code: a12 – ‘Pump P1 inverter low flow’ (engineer to clear)
Pump P1 has not reached the correct differential pressure in the specified time limit
via the inverter drive. Alarm will cancel when inverter receives a reset signal
(controller will pulse a reset to inverter on new pump start signal after fault received) .
Action: Check unit has been set up for the correct number of racks. Check inverter
drive for faults. Check non-return valves are not sticking open.
Code: a13 – ‘Pump P2 inverter fault’ (engineer to clear)
Pump P2 is drawing more than the over current setting in the inverter drive. Alarm will
cancel when inverter receives a reset signal (controller will pulse a reset to inverter on
new pump start signal after fault received).
Action: Force Pump 2 to run using ‘Manual Control’ function and measure current
drawn by pump. If higher than inverter setting (see page 19), then pump
should be replaced. If current is OK, then replace inverter drive unit.