This is a resin waveguide cover that sits inside the microwave cavity and shields the magnetron opening from food splatter and moisture. It allows microwave energy to pass through while protecting internal components. Replace this cover if it is cracked, burned, warped, or if you notice arcing or sparking during operation.
Do-It-Yourself Stories from Customers like You
Arcing from the magnetron intermittantly Peter V. • Georgetown , KY • September 29, 2015
I searched the web and it seemed that many people had a similar problem when gunk got on the waveguide plate/cover. When I removed the cover, one of the plastic latches broke so rather than just trying to clean the plate, I had to order a new one. The new one arrived in just a couple of days, I put the plate on and at least for the last few days, no more arcing. <$10 fix for my over the stove microwave.
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