View of PTAC unit removed from wall sleeve-room side is to right. Inset in upper left shows front view of unit in sleeve with cover removed. Supply fan draws unconditioned outdoor air (red arrows) into supply fan plenum. Fan also draws room return air (yellow arrows) through evaporator coil cooling room air (blue arrows). Unconditioned outside air mixes with conditioned room air and discharges to room (green arrows) through supply air louvers.