Table of Contents
Advertisement
Managing the alarms
S.N0
Alarm
1
Proof of Air Flow
Alarm (fan
state)
2
Space Freeze
Protection
Alarm
3
Sylk Device
Communicatio
n Failure
4
Discharge Air
Temperature
sensor failure
Managing the alarms
Trigger Scenario
An input (e.g., a current switch or
differential pressure switch) should be
available to monitor proof of air flow in
the Fan Coil Unit. When configured, the
control system will check this digital
input once per second. If the fan is
supposed to be on but is not, an alarm
should be generated.
For example, users can configure a
DIO/UIO terminal as a binary input to
detect the fan's status. When DIO2 is
set as the Fan Command, and the
device sets DIO2 to 'on,' if the digital
input indicates no air flow for 60
consecutive seconds, a 'Proof of Air
Flow' alarm will be triggered.
When the space temperature falls
below 42.8°F (6°C) for more than 2
minutes, a frost alarm will be triggered.
If the controller is disabled, in test
mode, or in any other higher-priority
mode defined by the application, the
frost alarm will not be activated.
If any of the Sylk sensors experience a
malfunction, an alarm will be activated.
This alarm will provide detailed failure
information sourced from Sylk, e.g.,
addr10: DAT sensor malfunction.
1. DAT sensor fault: Open/short limit is
detected on Discharge air
sensor(DIO1/DIO2/UIO1/UIO2)
2. DAT reading outside of the following
range (Range can be set on the Alarm
Limits screen):
High Limit: default 80°F,70°F to 180°F
Low Limit: default 45°F,35°F to 65°F
Action
Depending on the alarm
configuration:
1. Display Only: An alarm will be
generated, and an alarm indicator
will be displayed.
2. The control system will shut down
both heating and cooling outputs.
The fan speed will follow the fan
control logic.
(1) The fan will remain on if there is
still a call for heating or cooling.
(2) In other scenarios where the fan
should be on, the fan will operate
based on the scheduled status:
when the fan speed is set to low/
medium/high, it will be on if the
schedule status is 'occupied,'
'temporary,' or 'permanent.' If the fan
speed is set to 'circulate,' the fan will
run for at least 20 minutes per hour.
3. Upon Alarm: Dehumidification
will be disabled. Both cooling and
heating outputs, as well as the fan,
will be turned off.
1. If the system mode is set to OFF,
the freeze protection feature will
activate, utilizing the effective
heating setpoint, until the room
temperature reaches either the
heating setpoint or 8°C (46°F).
2. If the system mode isn't set to
OFF, it will operate based on the
standard control logic.
In case a sensor malfunctions, the
thermostat will deactivate all control
functions linked with that sensor,
behaving as if that sensor had never
been set up.
1. DAT sensor fault: The thermostat
will deactivate all control functions
related to the failed sensor,
meaning it will function as though
the sensor wasn't configured.
2. DAT out of range: The thermostat
will not deactivate the control
function. The user need to check the
equipment for correct operation.
MANAGING THE ALARMS
Level
High
High
High
High
(failure)/
Medium
(out of
range)
105
- Quick Links:
- Terminal Assignment
- I/O Terminal Assignment
Hide quick links:
Advertisement
Table of Contents
