User's Manual

Alarm Descriptions and Solutions
Liebert
®
DCP
™
66
6.3 System Shutdown Causes
Unit Is Off By Coolant Sens Fail
The control has lost its signal from the coolant temperature sensor. The control has no way of
controlling the coolant temperature, so the unit is shut off. Main power (disconnect switch) must be
turned Off, then back On to clear this alarm.
Unit Is Off By High CW Temp
The entering chilled water temperature is too high to keep the pump(s) running normally. If a HIGH
CW TEMP alarm occurs and the pump loses flow, then the Liebert DCP will go into a pre-chill mode.
The Liebert DCP can attempt to start again only if the entering chilled water temperature drops below
the HIGH CW TEMP setpoint.
Unit Is Off By Pump Short Cycle
The control was unable to get a pump started upon startup or after a loss of flow. The control looks at
the SHORT CYCLE time delay. If it cannot establish flow within that amount of time, the unit is shut
down. Main power (disconnect switch) must be turned Off, then back On to clear this alarm.
Unit Is Off By Low Coolant Temp
The control was unable to raise the coolant temperature to the calculated fluid temperature control
point. The unit is shut down because if the control cannot raise the coolant temperature to the
calculated coolant temperature control point, water may condense on the coolant piping and receiving
coils. Main power (disconnect switch) must be turned Off, then back On to clear this alarm.