Daikin DPS Installation And Maintenance Manual page 77

The Fan Fail alarm is initiated if these conditions are
encountered three times between 2:00 am of one day and 2:00
am the following day . If the Fan Fail alarm is then cleared, the
process may be repeated so that the unit may be shut down up
to three more times .
If differential pressure switch PC7 fails to detect airflow for
longer than the airflow timer (Default = 120 seconds) and on
VAV units the current duct static pressure indication is less
than half the static pressure set point after the unit leaves the
Startup operating state or any time afterward, while the unit
is running, the Fan Fail fault occurs . When the Fan Fail fault
occurs, the unit is shut down . It remains shut down until the
Fan Fail fault is manually cleared through the unit keypad or
via a network signal .
NOTE: There is no Fan Retry function or three retry function
when a unit has a CAV supply fan .
Low Discharge Air Temperature – (Lo
Disch Temp: Fault)
If the unit is not in the operating state and the discharge air
temperature is less than the Low Discharge Temperature Limit
(Default = 40°F) for longer than 30 seconds and the supply
fan has been on for longer than the LowDAT temperature
alarm delay (Default = 6 minutes), the Low Discharge Air
Temperature fault occurs . When the Low Discharge Air
Temperature fault occurs, the unit is shut down . It remains shut
down until the Low Discharge Air Temperature fault is manually
cleared through the unit keypad or via a network signal .
High Discharge Air Temperature – (Hi
Disch Temp: Fault)
If the discharge air temperature is greater than the High
Discharge Temperature Limit (Default = 170°F) and the supply
fan has been on for longer than the Temperature Alarm Delay
(Default = 30 seconds), the High Discharge Air Temperature
fault occurs . When the High Discharge Air Temperature fault
occurs, the unit is shut down . It remains shut down until the
High Discharge Air Temperature fault is manually cleared
through the unit keypad or via a network signal .
High Return Air Temperature – (Hi
Return Tmp: Fault)
If the return air temperature is greater than the Return Air
Temperature Limit (Default = 120°F) and the supply fan has
been on for longer than the temperature alarm delay (Default
= 30 seconds), the High Return Air Temperature fault occurs .
When the High Return Air Temperature fault occurs, the unit
is shut down . It remains shut down until the High Return Air
Temperature fault is manually cleared through the unit keypad
or via a network signal .
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Duct High Limit Fault – (Duct Hi Limit:
Fault)
If the unit is variable air volume, the contacts of the duct high
pressure limit control (DHL) open, and the unit state is not Off
or Startup, the Duct High Limit fault occurs . When the Duct
High Limit fault occurs, the unit is shut down . The unit remains
shut down until the Duct High Limit fault is manually cleared
through the unit keypad or via a network signal .
Discharge Air Sensor Fault – (Disch
Tmp: Fault)
If the discharge air temperature sensor (DAT) is open or short
circuited for longer than the Sensor Alarm Delay (Default=
30 seconds), the Discharge Air Sensor fault occurs . When
the Discharge Air Sensor fault occurs, the unit is shut down .
It remains shut down until the Discharge Air Sensor fault is
manually cleared through the unit keypad or via a network
signal .
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