I have a through-wall PTAC unit in an apartment building. It's enclosed in some cabinetry with a stone top. The stone top has a grille in it that is supposed to allow air to flow out of the PTAC into the room.
However, presumably because of the angle of the vent on the PTAC, the air gets trapped inside the cabinet and the room is not effectively heated/cooled.
Any ideas for how I could redirect the air straight upwards?