In the Underfloor Return System design, outside air and return
air from the room are mixed and filtered, then cooled or heated
through the zone unit; and finally introduced into the Raised
Access Floor plenum by the Zone Units.
In this System design, the floor plenum is divided into air
paths by underfloor baffles, allowing supply and return air
paths to and from the zone unit through the floor plenum.
In the Underfloor Return System, the return air is returned
to the bottom of the Zone Unit from the floor plenum.
