I work 8-5, so yes, I realize apple is open during these hours. I know they are open until roughly 6 or 7pm. It's the after 5pm hours, and sat/sun hours I'm interested in. So I can plan my week.
An air gap for a dishwasher is a requirement set forth by local plumbing codes. It is a device designed to ensure water flows only in the right direction during the dishwasher cycle. As a dishwasher operates, hot water flows in from the sink's hot water connection.
A return air grille is often fitted with a filter to trap smaller particulate materials before they have a chance to get into the ductwork. This limits the amount of cleaning needed and also keeps the system running smoothly, reducing the risk of clogs caused by dust, pet hair, and other materials.