we have 12 years and it takes longer to cook?

A microwave oven's power diminishes over time because its magnetron tube weakens. A magnetron tube is a high-voltage system that uses magnetic and electrical fields to create the oscillating waves that bounce around the oven and heat food. It is the source of a microwave oven's energy and power. So as the magnetron tube becomes weaker and less effective, the microwave oven becomes less powerful.

The typical magnetron tube has an average life of 2,000 hours of operation. That means you should be able to cook and heat food in a typical microwave oven for 2,000 hours before then oven loses power. This may not seem like a lot of time until you think about how you use your microwave oven. If you are like most people, you probably use it for a few minutes or seconds at a time. If you used the microwave oven for a total of 15 minutes every day, it would take 22 years for it to reach the 2,000-hours-of-operation point.

Do Microwave Ovens Lose Power With Time?
Well, now we know ......

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