Chiller Problem Alarms; Csm Alarms Available For Hardwired Chillers; Table 29. Csm Alarms Available For Hardwired Chillers - McQuay MicroTech II Operation Manual

Fault (Check Unit for Details)
If the chiller's alarm output relay is switched (steady), the "Fault (Check Unit for Details)" alarm will occur. Upon receipt
of this generic alarm, the CSM sets the chiller unavailable and disables it (if enabled). The chiller will not be enabled again
by the CSM until the chiller's alarm output relay changes to a non-fault state. This alarm is automatically cleared at the
CSM when the alarm no longer exists at the chiller.
COMP STOP - Evaporator Water Flow Loss
If the evaporator flow switch re-opens for a period of three seconds anytime after the chiller is running, the
COMPRESSOR STOP – Evaporator Water Flow Loss alarm occurs. This is a Fault alarm and the chiller is immediately
disabled and remains disabled until the alarm is manually cleared at the CSM user interface. Note that this alarm cannot be
cleared at the chiller. The chiller may also have a similar alarm that may require clearing.
COMP STOP - Condenser Water Flow Loss
If the condenser flow switch is open for any period greater than fifteen seconds after the evaporator flow has been proven,
the COMPRESSOR STOP – Condenser Water Flow Loss alarm occurs. This is a fault alarm and the chiller is immediately
disabled and remains disabled until the alarm is manually cleared at the CSM user interface (note that this alarm cannot be
cleared at the chiller).
If this is an air-cooled chiller, place a jumper across DI 2 to disable this alarm.

Chiller Problem Alarms

Problem alarms are defined as alarms that affect the operation of the chiller but do not shut it down (cooling capacity still
available). A flashing (open/closed) alarm output contact from the chiller indicates to the CSM that the chiller has a
Problem alarm. The CSM reads the status of the alarm signal input approximately every two seconds, which means that the
frequency of the flashing relay must read both open and closed at least once within the period of time defined by the Fault
Alarm Proving Time (see Table 27). A chiller's alarm contact must be steadily switched for a period of time greater than
the Fault Alarm Proving Time for the CSM to consider the alarm a Fault.
Problem (Check Unit for Details)
If the chiller's alarm output relay is flashing (alternately opened and closed), the "Problem (Check Unit for Details)" alarm
will occur. The CSM takes no action upon receipt of this alarm, but the alarm is displayed and logged to alert the operator
of a chiller generic alarm. This alarm is automatically cleared at the CSM when the alarm no longer exists at the chiller.

CSM Alarms Available for Hardwired Chillers

CSM alarms are broken down into the three types: Fault, Problem and Warning alarms. The Fault alarm type consists of
alarms that shut down the CSM. The Problem alarm type consists of alarms that affect the control of the system, but do not
shut the system down. The Warning alarm type consists of alarms that do not affect the control of the system and are for
the operator's information only. Chiller alarms displayed by the CSM from a hardwired chiller are limited to the following
alarms. Additional alarm information may be available at the chiller unit controller.

Table 29. CSM Alarms Available for Hardwired Chillers

Alarm Alarm Alarm Message
Type Priority
Fault 0 No Chilled Water Flow
Problem 10 Comm Loss Between CSM and
Chiller X
No Evaporator Flow After
Enabling Chiller X
Warning 100 Cooling Tower Alarm X
Chiller Off-line
Page 132
Indication
All cooling load pumps failed, resulting in a loss of chilled
water flow to the loads
Communications lost between CSM and Chiller X
After a chiller is enabled, the evaporator flow switch must
prove flow before the Wait For Evaporator Flow Timer
property expires
Cooling towers partially or totally failed. See the value
column of the Alarm View screen to determine which
cooling tower output is in alarm
At least one chiller that is part of the current sequence is
unavailable to the CSM
Reset
Manual
Auto
Manual
Auto
Auto
OM 780-2