On 18 Jun, 11:44, "dnoyeB" wrote:
On Mon, 18 Jun 2007 07:35:09 -0700, DerbyDad03 wrote:
When the AC is being used, my basement tends to get about 5 degrees
cooler than the first floor. The basement is used for laundry, storage
and my workshop, so it doesn't need to be that cold.

Here's my idea: Cut a hole in my return trunk, near the floor, to
recapture the cooler air and send it back upstairs. I'd install a filter
and design it so it could be easily sealed up in the winter.

So, if this isn't a ridiculously bad idea, how would I go about
determining the correct size for the opening?

Sorry to inform you, yes it is a rediculously bad idea

Getting air out of a room is just as important as getting it in when you
want to control the temperature. If you cut the return, you will stop air
from leaving the rooms upstairs. That will mean less air will enter those
rooms. Perhaps that air is cooler now, but I am willing to bet the
reduced quantity is going to hurt you big time.

I doubt your A/C has problem cooling the warmer air it sucks in from the
returns now. If it does you need some work.

I closed all my basement vents.

what you can do is run the fan only. the air coming out will still tend
to be cooler. but it raises the household humidity.

Thanks for the response.

All of my basement vents are closed and I've sealed all the seams on
the furnace/blower unit. I haven't attempted to seal all of the duct
work and insulating all of it would be a major undertaking. I'm not
sure I could do either without dismantling the whole system. A lot of
the ductwork is right up against the floorboards/joists, so there is
not a lot of room for insulation or even room to wrap the seams with
tape.

I have an "chute" where the main stack runs from the basement to the
attic, with an plumbing access panel on the second floor landing. What
if I dropped a length of 4" PVC down this chute and rigged up a fan to
draw the air up from the basement to the second floor? It would drift
back down to the first floor via the stairs.

One last question about something you said:

-- I doubt your A/C has problem cooling the warmer air it sucks in
from the
-- returns now. If it does you need some work.

How would I know? This is my first full season with AC and I really
don't know how to tell if it's working correctly. It seems to take a
very long time to cool the house down, especially compared to how fast
the same system warms the house in the winter.

Anything I can check? Return air temp vs. output air temp?