An apparatus for dispensing solid articles includes a manifold assembly. The manifold assembly includes a manifold and a door assembly. The manifold has a plenum and an inlet port in fluid communication with the plenum. The door assembly includes a door panel and a shield. The door panel is selectively moveable between a closed position, wherein the door panel restricts airflow through the inlet port, and an open position, wherein the door panel permits airflow through the inlet port. The shield defines a pocket to receive the door panel in the open position and thereby reduce or restrict flow of air behind the door panel.