Do Microwave Ovens Lose Power With Time?

Microwave ovens have become a staple of kitchens, and most people are so used to being able to heat food in their microwave oven quickly and easily that they don´t stop to think about how well the appliance functions. If you think your old microwave oven has slowed down or lost some of its power, you may be correct. Over time, microwave ovens lose some of their power and cooking ability.

Mcrowave ovens become less effective as they age.


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.

Magnetron Tube Lifespan

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.

Lifespan Reduction Factors

Although the average life of a magnetron tube is 22 years, a number of factors can cause that number to diminish and for the microwave oven to lose power more quickly. They include frequently putting too much metal in the microwave oven, consistently powering the it through a voltage that is too high or too low, improperly installing the appliance, obstructing the microwave oven's wave-guide and continually using the device at the upper limit of its heat tolerance.

Replacement Considerations

A busy restaurant might need to replace its microwave ovens every year, but you may not. If your microwave oven is several years old and you think it has lost power, then its magnetron tube is probably reaching the end of its life. In that case, it may be time to buy in a new microwave oven. If your fairly new microwave oven has trouble heating or cooking food, however, then you might want to consider trying to repair it before you invest in a new microwave oven.

Megan Holahan

Based in Southern California, Megan Holahan has been writing articles for online publications since 2011. She specializes in home and garden, and fashion and style topics. Holahan holds a Bachelor of Arts in political science and English from Bucknell University.