Microprocessor Controller for DOAS
7
®
Alarms
The microprocessor controller includes a digital output
for remote indication of an alarm condition, which
connects via the
J15
port. Possible alarms include:
•
Dirty Filter Alarm:
If the outside air or return air
filter differential pressure rises above the differential
pressure switch setpoint, the microprocessor
controller will activate an alarm.
•
Supply and Exhaust Air Proving Alarm:
Microprocessor controller monitors proving switch on
each blower and displays an alarm in case of blower
failure.
•
Sensor Alarm:
Microprocessor controller will send
an alarm if a failed sensor is detected (temperature,
pressure, relative humidity).
•
Supply Air Low Limit:
If the supply air temperature
drops below the supply air low limit (35°F), the
microprocessor controller will de-energize the unit
and activate the alarm output after a preset time
delay (300s).
•
Other Alarms:
Wheel Rotation, High Wheel
Pressure, High/Low Refrigerant Pressure.
Sequence of Operation
