Francesco,
Marcus and I agree:Â
- AHU fans run continuously during occupied hours
- PFP fan runs whenever the airflow fraction drops below 30% (The PFP fan is "available" 24/7, but only runs when the airflow fraction is lower than the setting)
Perhaps we're understanding some terms differently? "Available" does not mean the fan is actually running in the E+ program; it means that it is permitted to run if needed for temperature control or other reasons. Have you used output:variables to monitor what is happening?
The Night Cycle Manager has a similar feature.Â
- The Applicability Schedule determines when AvailabilityManager:NightCycle is used.
- The Fan Schedule identifies the "occupied" and "unoccupied" periods.
- Then the :NightCycle control turns on the fan when schedule #1 is "ON", schedule #2 is in  the "unoccupied" period AND the zone needs heating or cooling.
I hope that helps and is not too basic - I think I may be missing part of the reason for your questions.