This module generates an Unoccupied Status for AHUs that perform DA-T Control (both constant DA-T and single zone Cascaded DA-T). When not Unoccupied, the Status is Unocc Cntrl Not Req'd.
When unoccupied, the zone temperature is monitored to determine when the temperature exceeds the band specified by the two unoccupied temperature setpoints. When this occurs, the Unoccupied status is set appropriately (Unocc Cooling or Unocc Heating) until the zone temperature is satisfied for the length of time specified by the satisfied timer duration. After that period of time, the status is set to Satisfied.
If the temperature is unreliable when unoccupied, the Unoccupied Status is set to Unreliable. When commanded to Vent, the unit runs with maximum outdoor air. When units that serve multiple zones (that is, Cascaded Zone Control = False) are commanded to Warmup or Cooldown, the units run continuously to provide warm or cool air. In both cases, the sequencer switches to Not Unoccupied to allow the main AHU sequencer to control the heating and cooling devices.
You can view and modify the modules in this group’s logic.