You would size the registers for "throw " that's at least 6 to seven feet high ,so the conditioned air "covers" the "occupied"(where people are standing etc.) zone.Critical in cooling to prevent stratification of the air in the occupied zone.Originally posted by hvac-tech-lane
Dash, under the scenario of a second story with floor supplies and a floor return what supply grill face velocity do you set your system up for?Originally posted by dash
Common misconception but the location,high or low ,for returns has very,very little effect on operation or comfort.
You do need a return on each floor and a return "path" from all rooms .back to the main return ,as a minimum .
Keep the velocity below 600 fpm,per grille mfr. spec sheet.