On Sep 19, 10:29*pm, Ed Pawlowski wrote:
On Wed, 19 Sep 2012 20:37:19 -0400, Jan Philips

wrote:
We are having our kitchen remodeled. We are reusing our microwave oven
(a Kenmore 665.6170911). *The contractor says that there is supposed
to be a piece on top of it that lets air out the vent but closes to
keep anything from coming in. *I looked in the manual and don't see
anything like that, even in the installation instructions. Is there
such a thing, and if so, how can I find out the part number for one
for this microwave oven?

In my limited experience of installing three such microwaves, none had
an included damper. *It had a duct outlet, but the damper was provided
by the installer or customer.

They are readily available at home stores and come in a variety of
sizes.

+1 to that. I don't see why the contractor doesn't just
put one outside, where the exhaust exits. I'd much
rather have it there. If it gets stuck, dirty, etc it's
accessible instead of being buried above an installed
microwave.