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The problem started recently. I cook a lot and especially love baking cakes and roasting all sorts of vegetables in the oven. Recently when roasting, I noticed smoke coming out of the oven and the fire alarm went off.
It was because a lot of grime and food drippings had accumulated (for over a year) at the bottom, and it was getting charred. The next day I cleaned up the whole oven (applying baking soda paste overnight then scrubbing with vinegar and steel wool). Except for the top of the oven which I simply can't get perfectly because that would require me to bend over backwards and clean, the rest is all squeaky clean.
However now when I try roasting above 350 F, it still causes the fire alwarm to go off. There's nothing else in the oven that's getting burnt, even the veggies I placed in the oven weren't done completely. I am really puzzled. Any suggestions?