High velocity or not,the supply air needs to get back to the return ,somehow.Under the door may be a path ,if not enough add a return,or transfer grille.Originally posted by zoom38
In the Unico install manual they only have one central return. Is this not the way to do it? Should there be a return in each room? Or is it that because it is hi velocity only one central return is necessary.
If the supply air to a bedroom,can't get out and back thru the return to the fan,that room will become pressured ,causing "exfiltration",air being forced out of the house.
The return is "looking" for that air,air in the fan equals air out,if it can't "find",it causes infiltration,pulling out side air in,in the part of the home with the return.
Can be a major factor in high bills,and indoor air quality.