Daikin MicroTech III Operation Manuals page 80

OAD Stuck
A warning alarm indicating the outdoor air dampers are stuck
and not modulating will be generated whenever the damper
are stuck open or stuck closed .
The dampers are considered stuck open when either of the
following abnormal situations occurs:
• The damper command value is less than the calibrated
damper end switch closed value continuously for 180
seconds yet the outside air damper end switch input
remains open .
• The damper end switch input does not change from
closed to open with 30 seconds of the damper command
value dropping (and remaining) below the calibrated
damper end switch open value (less the calibrated
maximum switch differential) .
The dampers are considered stuck closed when either of the
following abnormal situations occurs:
• The damper command value is greater than the
calibrated damper end switch open value continuously for
180 seconds yet the outside air damper end switch input
remains open .
• The damper end switch input does not change from
closed to open with 30 seconds of the damper command
value rising above the calibrated damper end switch
closed value (plus the calibrated minimum switch
differential)
The damper stuck warning will also be generated when the
damper end switch operation is unreliable . The ends switches
are considered unreliable when the end switch input remains
closed when the damper command value is between the
calibrated end switch closed and open values (plus and minus
the calibrated minimum and maximum switch differentials) .
The alarm will automatically clear when the conditions causing
the alarm are no longer present .
OM 920-6 • MICROTECH UNIT CONTROLLER
Dirty Filter - (Dirty Filter: Warning)
If the pressure drop across the filter section in the unit
exceeds the setting of the differential pressure switch the
Dirty Filter warning occurs . When the Dirty Filter warning
occurs, unit operation is not affected . The Dirty Filter warning
must be manually cleared through the unit keypad or via a
network signal .
Airflow Switch - (Airflow Sw: Warning)
If the unit has been in the Off operating state for at least
thirty minutes and the PC7 airflow switch input to the main
controller indicates airflow, the Airflow Switch warning occurs.
This normally indicates a problem with the PC7 airflow switch.
When the Airflow Switch warning occurs, unit operation is not
affected. When the alarm condition is corrected, the Airflow
Switch warning must be manually cleared through the unit
keypad or via a network signal .
Conductivity - (Conductivity: Warning)
If the unit is equipped with a Dolphin system and the
Conductivity value rises above the alarm setpoint value,
the conductivity alarm occurs . When the alarm condition is
corrected, the conductivity warning must be manually cleared
through the unit keypad or via a network signal .
Return/Exh Fan Warning
When the unit is equipped with a Return/Exhaust fan VFD or
ECM motor and a loss of Modbus communications for longer
than 10 seconds a Return/Exhaust fan warning alarm occurs .
The alarm is automatically clears when the condition causing
the alarm is corrected .
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