Many of the VAV terminals on the lab side of the OSB have been showing erroneous airflow readings and damper positions. I believe the cause of this is the VAV programming, which was written to drive the dampers closed during unoccupied hours, during which the damper actuators would calibrate their zero points to maintain correct readings of airflow and damper positions. Because these VAV units never go unoccupied since they are not on a schedule, the controllers have drifted over time and their zero points are no longer accurate. To correct this, I switched half of the VAV units to unoccupied mode, but the fans in AHU-3 did not respond quickly which led to an overpressure condition in the supply ducting which tore the flexible ducting at a VAV terminal in the control room. We had to shut down AHU-3 in order to get the duct reattached. This shutdown occurred ~8:30 local time and lasted about a half hour. Prior to the shutdown, their was a period of time ~10 minutes in which the airflow noise in the control room dramatically increased. 

The VAV reset was mildly effective; the cold deck static pressure was trending at .06" W.C. before the reset. After the reset it is trending closer to .09" W.C. The hot deck static pressure was trending at .09" W.C. prior to the reset, and at 1.4" W.C. after the reset. This shows that some of the terminal units have adjusted their flow rates, but there are still erroneous readings which will require further investigation.