Small closet containing air handler in center of ranch style house with hall way to bedrooms. What are advantages/disadvantages of a short duct from air handler to ret. grill in closet wall? Is there a problem with no duct and using a large filter rack on top of air handler? The closet space would be a return plenum. I can cut a return opening through one wall to a bedroom, no duct. The other two bedrooms could use return grills cut through the wall into the hall way. This would keep return ducts out of unconditioned space.
Theres no advantage to this at all.
Most mobil homes are this way.
the disavantage is the bedrooms being cut off from return air when the doors are shut.
That makes recirculation of the air impossible.
If you cut holes in the walls to let the return air pull from the room. Now you have noise in the bedroom that you can't block off. Or (noise coming from the bedroom)
A cheap way out is to cut the bottom of the doors,
Air can be pulled from the space below the door, when it's shut. Not ideal, but it's cheap.
Thanks Toolpusher. I may try doing it this way. I read of a trick to cut down on the noise when cutting return air passage through the bedroom wall. Put one grill up near the ceiling on one side of the wall and on the other side put it nearer to the floor as long as there is no fire block in the wall space. Should be better than a gap under the door.