Hello,
I'm having an issue with the supply fan on a packaged VAV with reheat coming on during unoccupied periods when the space temperature is satisfied. The heating coil has 0 output during these hours. It's very inconsistent, sometimes it runs and other times it operates as designed. I've looked over the schedules, changed the schedules, looked at exhaust and a variety of other items. It does appear to happen move often during the heating season, but there is not a consistent pattern for every packaged unit. Besides the space temperature, what else can cause a supply fan to turn on during unoccupied hours?

Thanks,
Adam Rustige