User manual

Alarm Descriptions and Solutions
33
• CONTROL VALVE FAILURE—Activated when the chilled water control valve has been com-
manded by the control to open or close and no change is detected from the valve-position signal.
The control will close the valve and then try to control the control valve based on its travel time.
Main power (disconnect switch) must be turned Off, then back On to clear this alarm.
• CONDENSATION DETECTED (optional)—Activated when water is detected at the Liebert
XD cooling module (24VAC is applied to the condensation input on the control). When this alarm
is active, the control will raise its refrigerant control point by 4°F (2.2°C). Alarm will reset when
the 24VAC signal stops being sent.
• FAN FAILURE (optional)—Activated when a 24VAC signal is applied to the fan failure input
on the control board. This alarm will reset when the 24VAC signal stops being sent.
• CUSTOMER INPUT 1—Activated when a 24VAC signal is applied to the customer alarm input
on the control board. This alarm will reset when the 24VAC signal ends. WATER UNDER
FLOOR and SMOKE DETECTED are possible designations for this alarm; they are set with the
Unit Code.
• SMOKE DETECTED—Activated when sensors detect smoke in the vicinity of the Liebert XDP.
• WATER UNDER FLOOR—Activated when sensors detect water under the raised floor under
the Liebert XDP.
• UNIT X DISCONNECTED—Activated when a unit has been disconnected from the network.
• LOSS OF POWER—Activated when the unit is On and operational and 24VAC power to the con-
trol is lost. This alarm will be emitted when power is restored to the control. The Liebert XDP will
restart at a user-defined time delay after power is restored. The alarm will reset itself after 30
seconds of run time.
7.2 Display Lamp Indicators
• The Green lamp will be On only when the Liebert XDP is On and running with no alarms.
• The Red lamp will be On if the unit is On and running with an active alarm, or if the unit is shut
down because of a certain alarm.
• The Red lamp will flash while an alarm is being annunciated. The Red lamp will stop flashing and
the beeper in the display will stop beeping when the ALARM SILENCE / ? key is pressed.
• The Amber lamp will be On if the Liebert XDP has been shut down at the I/O switch or if the unit
has been shut down by an alarm condition.
7.3 System Shutdown Causes
Unit Is Off By Refrig Sens Fail
The control has lost its signal from the refrigerant temperature sensor. The control has no way of con-
trolling the refrigerant 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 refrigerant pump(s) running normally. If
a HIGH CW TEMP alarm occurs and the refrigerant pump loses flow (differential pressure), then the
Liebert XDP will go into a pre-chill mode. The Liebert XDP can attempt to start again only if the enter
-
ing 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 differential pressure. The
control looks at the SHORT CYCLE time delay. If it cannot establish differential pressure 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 Refrig Temp
The control was unable to raise the refrigerant temperature to the calculated refrigerant temperature
control point. The unit is shut down because if the control cannot raise the refrigerant temperature to
the calculated refrigerant temperature control point, water may condense on the refrigerant piping and
receiving coils. Main power (disconnect switch) must be turned Off, then back On to clear this alarm.
NOTE
This is not a room smoke detector and is not intended to replace external smoke detectors.