Abstract: An air handling unit includes a manifold having an inlet configured to receive a supply of air, a plurality of apertures formed in the manifold, the apertures enabling a passage of air from the manifold out of said the handling unit, a bypass plenum formed in the manifold, and a damper positioned within the bypass plenum. The damper is pivotable between a closed position and an open position to allow air from the manifold to exit the air handling unit without passing through the apertures when a pressure within the manifold exceeds a threshold pressure.