This module generates the on or off state for the control of a parallel fan within a VAV application according to a flow based algorithm.
If the unit is in Occupied, Standby or Bypass mode and the flow is less the Parallel Fan Occ Min Flow setting, the state output is on. Additionally, if the heating or cooling command are greater than the Fan On Threshold, the state output is on. When the heating and cooling command are both below the Fan Off Threshold, the state output is off. If the Heating Purge Duration is greater than zero, the Heating Command must be below the Fan Off Threshold for the time specified before the state output is off.
This module can be used to provide the on command to single speed fans, three speed fans, or proportional fans.
You can view and modify the modules in this group’s logic.