Function	Filter perspective	Valve, supply routing	Valve, return routing	Purpose
Filter	In from supply, out to return	Pool drain/skimmer to filter supply (housing)	Filter return pipe to pool jets	Normal filtering of pool water
Backwash	In from return, out supply	Pool drain/skimmer to filter return (grid interior)	Filter supply pipe to street	Send old, used DE accumulated on outer surface of grids to the street.
Rinse	In from supply, out to return	Pool drain/skimmer to filter supply (housing)	Filter return pipe to street	Send any particles/sentiment accumulated inside the grids into the street. This is done after backwash because the backwashing process pushes unfiltered water, possibly including leaf or pine needle fragments, into the interior of the grids. You don't want that junk going back into your pool, so you rinse it out into the street.
Waste	No flow	Pool drain/skimmer to street	Pool drain/skimmer to street	Lower the pool level without involving the filter
Recirculate	No flow	Pool drain/skimmer to pool jets	Pool drain/skimmer to pool jets	Provide pool circulation without involving the filter
Close	No flow	No flow	No flow	???