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Microwave Magnetron tube has arced

The magnetron in our Bosch HMB405/01 microwave has arced and burned the interior wall of the microwave. The wall surrounding the opening to the magnetron is burned enough that the metal is pitted. Obviously the tube needs replacement. What else needs to be done?

Tom Quattlebaum
After few seconds the cooking cycle has started, the magnetron in my BAJAJ microwave(don't know model number) sparks outside at wall & waveguide cover. It heat ups the food during that interval. It burns the little area around its opening and waveguide cover.

Is Diode Tube also faulty or should I just replace Waveguide & clean+repaint the wall ?

Thank you.
Murtuza Bharmal

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Posted on Feb 08, 2009


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Microwave Magnetron tube has arced

If the cavity metal of the oven is chipped or charred, it will have to be sanded smooth and clean and dried thoroughly.

Then you can apply some high-temperature appliance paint, available from hardware stores, department stores or appliance parts stores.

If your waveguide cover is burned, it will need to be replaced. It provides important protection for the magnetron.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

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