"Mikepier" wrote in message
ups.com...
First I like to thank everyone for helping me with my kitchen remodel.
I have yet another question.
My stove and microwave will line up between 2 studs. I want to vent
the microwave out of the back with a 3 1/4 X10 elbow, up between the 2
studs into the attic where it will go out a roof vent.
My queston is should the duct be flush with the sheetrock in the back
of the unit or should it stick out a little? How does the unit connct
to the duct? The instruction manuals on GE's website are kind of vaque
and really does not say how to attach the duct to unit.
Thanks again!

If you look at the square adapter that comes with the m/w, that is used for
venting, you'll see that it leaves a small projection that fits into the
elbow in the wall. However, usually, I think the m/w is vented out the back
normally when it is to be vented straight out the wall to the outside. Most
of the time, the m/w would be vented straight up into the cupboard above the
m/w, where it is converted to round pipe and then straight up through the
cupboard, the soffit, and then on up through the attic and out the roof. If
you're planning on just venting it into the attic and hoping a roof vent
will take care of the added moisture in the attic, I think you'll be
disappointed. Might not meet code, also, as it would have the potential to
push a stove top fire up into the attic. Furthermore, what did you plan to
do about getting that rectangular vent pipe in the wall, through the
horizontal 2x4 capping the wall joists. (couldn't remember what you call
it, actually). Around, here (Northern Illinois), hoods and m/w hoods are
usually ventless because of the loss of heated air and/or infiltration of
cold or hot air in the Winter or Summer. Back in the 70's during the first
energy crunch, I remember that in Wisconsin, you couldn't get a permit for a
gas furnace in new construction if the hood was vented. May not be that way
anymore.
Sorry for the lengthy post...(my experience was in selling these things from
their beginning until my retirement a couple of years ago.

Tom G