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No Evaporator Flow After Enabling Chiller X
Some chillers have a “Waiting For Flow” status condition where the compressors will not run because evaporator flow does
not exist. Since chillers may remain in this state indefinitely if flow is never provided, the CSM must recognize this
condition and enable different chillers to meet load requirements.
After enabling a chiller, the CSM monitors that chillers evaporator flow switch to verify that the evaporator pump operating
properly. After enabling, if flow is not proven by the time the “Wait For Evaporator Flow Timer” expires, the No
Evaporator Flow After Enabling Chiller X alarm will occur. The chiller will be disabled and the Next-ON chiller will be
immediately enabled. This alarm sets the chiller unavailable (Misc screen) which means the chiller will not be enabled
again until this alarm in manually cleared at the CSM user interface. For an indication of which chiller caused this alarm to
occur, the number in the Value column for this alarm in the View Alarm (see Figure 48) indicates the chiller number which
didn’t receive evaporator flow on startup.
Warning Alarms
Cooling Tower Fail X (x could be cooling tower output 1 through 16)
If a cooling tower output has been enabled and a contact connected to the cooling tower alarm input with the same number
is closed for the delay time of 30 seconds, the cooling tower fail X alarm occurs. When the contact connected to the alarm
input is opened again or the tower output is disabled for the delay time of 30 seconds, the alarm automatically clears. See
the Cooling Tower Output in Alarm value on the Clg Tower Status screen to determine X (which cooling tower output is in
alarm).
System operation is not affected by this alarm and wiring a contact to the tower alarm inputs is optional. This alarm is
provided so that an external alarm-logic circuit for cooling tower equipment can be field wired.
Leaving Condenser Water Temperature Sensor Fail Warning
If the common leaving condenser water temperature sensor fails while it is not the selected Control Temperature source for
the cooling tower, the leaving condenser water temp sensor fail warning alarm occurs as a Warning. System operation is
not affected by this alarm. When the alarm condition is gone, the alarm automatically clears.
If you don’t have a common leaving condenser water temperature sensor connected to the CSM, leave the Leaving
Condenser Water Sensor Present Flag = “No” (I/O Config screen) so that the alarm is inhibited from changing.
Entering Condenser Water Temperature Sensor Fail Warning
If the common entering condenser water temperature sensor fails while it is not the selected Control Temperature source for
the cooling tower, the entering condenser water temp sensor fail warning alarm occurs as a Warning. System operation is
not affected by this alarm. When the alarm condition is gone, the alarm automatically clears.
If you don’t have a common entering condenser water temperature sensor connected to the CSM, leave the Entering
Condenser Water Sensor Present Flag = “No” (I/O Config screen) so that the alarm is inhibited from changing.
Chiller Off-line
The chiller off-line alarm occurs whenever at least one chiller is part of the current sequence but unavailable. This alarm
does not affect system operation, but it is an indication that total system capacity will be decreased. When no off-line
chillers exist, the alarm automatically clears.
Chiller X In Alarm (x could be any commissioned chiller number)
The chiller X in alarm occurs whenever a connected chiller has at least one active alarm. When all chiller alarms are
cleared, the alarm automatically clears. For a text description of the current active alarms on a particular chiller:
1. See the “Alarm” line of that chiller on the Chiller Status screen.
2. See that chillers alarm log on the Misc screen.
3. Or go directly to the chiller’s unit controller.
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