Indirect/direct evaporative cooling system gets clean bill of health
The design takes advantage of northern California's arid climate to provide cost-efficient evaporative cooling with a VAV design that still manages to deliver excellent IAQ during the winter. This is unusual for VAV designs, which tend to decrease the supply air volume to the building as outdoor air temperatures drop. However, this particular AHU configuration includes an air-to-air heat exchanger, which can be used to preheat outdoor air, so that outdoor air minimum flow settings still exceed code.
One hundred percent outdoor air was desirable not only because of the high-density people loading associated with classroom environments, but also because this multi-function facility would provide limited dental care to uninsured members of the community, potentially increasing the number of airborne viruses.