Sequence of Operation
WSHP Open v3
CARRIER CORPORATION ©2021
Integration Guide
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31
Fan Status Alarm
(optional)
–
The control generates a fan status alarm if the fan status input detects the fan is
OFF after any fan speed output has been enabled. A 30 second alarm delay is used to allow the fan to start
operation before an alarm condition is detected. The control monitors the fan output and if the fan is operating at
any speed, the fan status must detect the fan is operating.
Compressor Status Alarm
–
The control generates a compressor failure alarm if the compressor status input
detects the compressor is OFF after the compressor output has been energized. A 6-minute alarm delay is used to
allow the compressor to start (prevents alarms due to timeguard operation) before an alarm condition is detected.
The control monitors the compressor output and if the compressor output is energized, the compressor status
input must detect the compressor operation.
Filter Status Alarm
–
The control provides the ability to generate a dirty filter alarm after the number of fan run
hours exceeds a configurable filter alarm timer limit. The control monitors the fan output and if the fan is
operating at any speed, it accumulates run time. If the fan run time hours exceed the configurable limit, an alarm
is generated. To reset the alarm timer after the alarm has been generated, a
Reset Filter Alarm
input is provided.
You can disable the filter alarm by setting the
Filter Alarm Timer Delay
to
0
(factory default).
Indoor Air Quality Alarm
–
The control provides the ability to generate a high CO
2
level alarm during occupied
periods when the CO
2
sensor value exceeds the adjustable limit. When a transition from unoccupied to occupied
occurs, or the occupied alarm limit is changed to a value that causes an alarm condition to occur, the control will
automatically calculate an alarm delay (equivalent to the configured delay time in minutes/ppm, times the error
that occurred, + 15 minutes). This prevents nuisance alarms from occurring when occupancy changes or the
setpoint is changed. You can disable the IAQ alarm by setting
Occupied High IAQ Alarm Limit
to
0
.
Relative Humidity Alarm
–
The control provides the ability to generate an alarm when the space relative humidity
exceeds the alarm setpoint. Separate occupied and unoccupied high humidity alarm setpoints are provided. The
control provides a 5-minute alarm delay during unoccupied periods. During occupied periods, the controller uses
the occupied high RH alarm limit. When an occupancy transition from unoccupied to occupied occurs, or the
occupied high alarm limit is lowered, causing an alarm condition to occur, the control automatically calculates an
alarm delay (equivalent to the configured delay time in minutes/% RH, times the humidity error condition that
occurred, + 15 minutes). This prevents nuisance alarms when an occupancy change occurs and allows time for
the unit to correct an alarming humidity condition.
Source Water Linkage Failure Alarm
(if
Source Water Linkage
was active)
–
The control generates a
Source
Water Linkage
failure alarm if Linkage fails after once being active. The Linkage status is monitored and if it fails
to be updated from the Loop controller, then a
Source Water Linkage
alarm is generated. There is a 6-minute
alarm delay to prevent false alarms.
NOTE
You can reset this alarm only by re-establishing Linkage and correcting the condition that caused the
Linkage failure, or by momentarily setting the
Shutdown
point to
Active
.
Airside Linkage Failure Alarm
(if
Airside Linkage
was active)
–
The control generates an
Airside Linkage
failure
alarm if Linkage fails after once being active. The Linkage status is monitored and if it fails to be updated from the
master zone controller, then an
Airside Linkage
alarm is generated. There is a 6-minute alarm delay to prevent
false alarms.
NOTE
You can reset this alarm only by re-establishing Linkage and correcting the condition that caused the
Linkage failure, or by momentarily setting the
Shutdown
point to
Active
.
OAT Sensor Alarm
(if
Network OA Temperature
was active)
–
The control generates an OAT Sensor failure alarm if
the value of OAT fails to be updated through the network after once being active. The update status is monitored
and if it fails to be updated, then an OAT sensor alarm is generated. There is an alarm delay (approximately 1
hour) to prevent false alarms, while minimizing the required update rate for OAT.
NOTE
You can reset this alarm by momentarily setting the
Shutdown
point to
Active
.
SPT Sensor Alarm
(if SPT sensor was active)
–
The control generates an SPT sensor failure alarm if the SPT sensor
fails to communicate with the control for 5 minutes or greater. The update status is monitored and if it fails to be
updated, then an SPT sensor alarm is generated.
ZS Sensor Alarm
(if ZS sensor was active)
–
The control generates a ZS sensor failure alarm if the ZS
sensor fails to communicate with the control for 5 minutes or greater. The update status is monitored and if it fails
to be updated, then a ZS sensor alarm is generated.
