Is there a problem with a microwave if when operating it the outside of the microwave gets hot?

Answer 1

The outside of a microwave oven will warm up through periods of use. That's normal. But how hot is hot? If you have any doubts, take the unit in or have someone come out and evaluate it. But before that, you might check to see that there is enough space around the unit for adequate ventilation. This is very important, and often overlooked. Your owner's manual will absolutely have this caution and some suggestions. Review it or get some professional input on the issue. When the microwave is on, the magnetron, the microwave generating device, creates a fair amount of heat. This heat is carried to fins (a radiator) on the tube, and a fan blows air through these fins. The air then blows into and through the cavity (the cooking area in the oven), and then out of the unit. In general, the air is drawn in from "one side" of the unit and exhausted on the "other side" of the unit. Poor ventilation allows increased "recirculation" of that air, and the effectiveness of the cooling system drops off dramatically. Having said this, you are smart enough to see the truth here. There are thermal sensors in at least two or three places in the unit that will shut it down if a fire begins in the cavity or the magnetron becomes overheated for some reason. As the microwaves heat the contents of the oven by heating the water in it, steam is often produced. And this heats the cavity walls and the cover or cabinet of the unit as the heated air from the magnetron's radiator is blown through the cavity. It is improbable that a microwave run for even a minute or two will not get somewhat warm to the touch. Why wouldn't it? But how hot it gets, at least as it is set down in the question, is subjective. Any doubts, and that means any doubts, should be cleared up by a technical professional.