HVAC air returns?

[Davej]

After thinking about this a bit I am curious whether new homes now offer two things that I think would improve they way air returns work in forced-air systems. In my ancient home I of course lack these...

1. Filters located at the entry of the air-returns rather than just before the furnace blower, so that your ductwork will get less dirty over the years.

1. Two level air returns, that can be closed, with one at the floor and one at the ceiling, so that in the Summer you would open the return at the ceiling and in the Winter you would open the one at the floor.

[trader_4]

I've heard of these, but never seen them. I've seen a few new construction homes around here, expensive ones, and all had filters only at the furnace, electronic ones.

I've never seen that either. I have seen return in the ceiling, but only for large homes where one furnace is in the attic for the upstairs part.

[clare]

The second is becoming more common. The first is not a good idea because restricting the inlet to the ducts will put the whole return duct at a lower pressure, causing it to pull dirt etc in through the gaps