Product data

Fan status alarm — Refer to the Fan Status Alarm table
for specifications.
FAN STATUS ALARM
FUNCTION DESCRIPTION
Controllers Monitor Thermostat
Sensor Required Airflow, Digital Input
Sensor Wiring
Terminals 8 and 9 of 33CSUCE-06
Relay Pack or Wire to Damper Board
Input
Open Contacts at Sensor from
Lack of Airflow
Output
Alarm SE-06, Cannot Detect Fan ON
Alarm SE-12, Cannot Detect Fan OFF
Configuration Option Fan Status
Configuration Values Default OFF, Min OFF, Max ON
Configuration Increments None
Associated Functions Fan Operation for Heat
Operation
The detecting or verifying fan is running. The fan relay
is on or Heat 1 relay is on.
When the monitor thermostat indicates commanded state
of FAN (relay) is on, but flow switch indicates no airflow af-
ter30-second timedelay(sensor contacts stillopen),an alarm
condition is initiated (heat or cool or ventilation mode).
When the monitor thermostat indicates commanded state
of HEAT 1 (relay) is on, but flow switch indicates no airflow
after 120-second delay time (sensor contacts still open), an
alarm condition is initiated. This delay time allows for units
having internal control of heat, versus thermostat control
of heat.
When an alarm condition is initiated:
• system mode (either heat or cool) is dropped
• alarm SE-06, Cannot Detect Fan ON, is issued
• a manual reset is required to reset the alarm
Detecting or verifying fan is OFF. Fan relay is OFF and
Heat 1 relay OFF.
When the monitor thermostat indicates commanded state
of FAN (relay) is OFF, but flow switch indicates that airflow
still exists after 120-second delay time from fan off com-
mand (sensor contacts still closed), an alarm condition is
initiated.
When alarm condition is initiated:
• heat, cool, and fan are shut off
• alarm SE-12, Cannot Detect Fan OFF, is issued
• a manual reset is required to reset the alarm
Configuration example
The Fan Status Switch option is set to ON.
At the start of a cooling mode, the fan relay is switched
on by the monitorthermostat. Fanoperation isinitiated and
the fan has 30seconds togenerate sufficientairflow to close
the normally-open fan-status flow switch. If the sensor con-
tacts are closed within 30 seconds, the system operates
normally and no Fan Status alarm is generated. If, however,
the sensor contacts are not closed within 30 seconds, an
alarm is generated. The thermostat display will not indicate
‘‘fan’’ until fan operation is verified by the fan-status flow
switch.
The alarm will cause the system to shut down. No cool-
ing, heating, or ventilation is available until a reset of the
system is initiated.
In a heat mode, the same sequence is followed, except
that the delay time is increased to 120 seconds. If the Fan
Operation for Heat option is configured OFF, no alarm is
generated in the heat mode.
Filter status alert — Refer to the Filter Status Alert table
for specifications.
FILTER STATUS ALERT
FUNCTION DESCRIPTION
Controllers Monitor Thermostat
Sensor Required Filter, 33CSFS--01, Digital Input
Sensor Wiring
Terminals 10 and 11 of
33CSUCE-06 Relay Pack or
Wire to Damper Board
Input
Closed Contacts from
High Pressure Drop
Output Alarm (SE-09), Dirty Filter
Configuration Option
Humidity Sensor/Filter
Status Switch
Configuration Values
Default 0, Min 0,
Max 2 to activate
Configuration Increments None
Associated Functions None
Operation
This alert is used to indicate the status of the filters in the
HVAC unit. The Dirty Filter alert indicates a high pressure
drop across the filters, caused by collection of excessive par-
ticles and debris on the filter media.
Pressure drop across the filters in the unit increases until
it reaches the Filter Status sensor’s set point. This causes
the contacts of the sensor to close. The contact closure of
the sensor is detected by a discrete input. If the contacts
remain closed for 10 minutes, a Dirty Filter alert is initiated.
A manual reset is required to clear this alert.
Configuration example
The Filter Status sensor will close contacts (alert) when dif-
ferential pressure increases from zero (clean filter, no re-
striction, or pressure drop across filter) to the sensor set
point (dirty filter with restriction across filter). The Humidity
Sensor/Fan Filter Switch option is set to specify the filter
status switch.
During operation of the unit over a period of time, an
SE-09 error is declared. This indicates that the differential
pressure across the filters has increased beyond the set point
value of the sensor. The Alternate Information ‘‘Dirty Filter
Status’’ (information item 10) will read ON, also indicating
a dirty filter.
After the dirty filters are changed, the Dirty Filter Status
must be manually reset. The system then returns to normal
operation and will not alert until the differential pressure set
point of the Filter Status sensor is again reached.
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