Couple of thoughts -
First, the BCU should not control the AHU via a schedule if it has VAVs. It should be using the VAS application - schedule>area>vavs>vas>ahu. If the AHU is not looking at the occupancy of the VAVs, I would suggest changing the programming. There maybe a mixed programming between area, vas, and schedule.
Also, is the BCU changing the mode of the PCM or is there a BOP it is referenced to?
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