"Kurt Ullman" wrote in message
...
In article
,
aemeijers wrote:


Within limits, you can do a poor man's zoning of the cooling system by
the old trick of partially blocking some of the downstairs registers and
air returns. Pay close attention though- if system starts running
longer, or coil starts freezing up, it didn't like whatever you did. Do
you have enough air returns upstairs? A lot of builders cheap out and
only put one in the center hallway, and count on air under the doors to
provide a return path. That often gets blocked by carpet. Try leaving
all the upstairs doors open during the day, if you normally leave them
closed.
The air returns are the ones high on the wall, right? Every
room upstairs (we have four bedrooms)has one. Each room also has at
least one and some have two on the floor. Kids have moved out, so we
don't use three of the four bedrooms. We turned off the registers and
keep the doors closed to these. Should we open them back up and them
maybe close the ones downstairs?


The 'returns' high on the wall are likely -supply- vents, not returns. And,
if there are three such vents, one is a return (on the floor or low on the
wall) and the other two are supply. One is for summer, (a/c) it is up high,
and the other is for winter (heat) it is down low. Unblock the return and
the upper vents, leave the other (heat) one blocked.