Why do I need mica in the microwave and what should I do if it burns out?

When the microwave starts to sparkle when turned on, most of us are in a hurry to give it up for repair. However, quite often the cause of the breakdown is not so serious and you can fix it yourself. This is the case when the mica for the microwave burned out. What is it, why is a mica plate needed and how to replace it at home?

Why in the microwave mica plate?

In order for our microwave oven to be able to produce microwaves, inside it has a microwave generator - a magnetron. Its waves enter the working chamber of the furnace through a special waveguide. It is his exit that closes the mica. However, it does not conduct electric current, since it is an insulator, but passes any radio waves.

What are the functions of a mica plate?

• Protects the microwave generator from heat during heating or cooking.
• Distributes the microwaves inside the chamber evenly.
• Protects the magnetron from molecules of aromas, particles of steam, fat, food, which, when using a microwave, will inevitably splash around the working chamber.

That is why the protective mica plate should always be kept clean. After all, moisture particles deform mica and lead to its rapid oxidation. And the remnants of food or fat, falling on a protective mica surface, begin to burn under the influence of radiation from a microwave generator. Further, the mica itself also burns out, and through these small “holes”, the radiation enters directly into the furnace chamber, leading to a change in the current propagation pattern and, accordingly, to breakdowns. From here sparks and crackles arise.

To avoid such problems, use a special plastic lid during heating or cooking to prevent food particles from splashing.

About the causes of burnout

In addition to the above reasons for the failure of the mica screen, there are less obvious ones. But all of them sooner or later lead to the need to replace mica in a microwave oven.

• Violate the circuit of the electric current in the furnace and cause arcing "with all the consequences" can dishes containing metal or crystal. Moreover, it does not have to be a completely crystal vase or a metal pan. For example, it is enough for a spoon accidentally forgotten in a plate, inlay or gilding along the edge of a plate, a metallized pattern on a mug. What does crystal have to do with it? Firstly, it does not withstand microwave loads due to its uneven thickness and can scatter into pieces right in the furnace, damaging our protective shield at the same time. Secondly, crystal almost always contains lead and even silver. That is - also metals.
• Even if the dishes are intended for microwave ovens, but at the same time its diameter is larger than a plate of a specific microwave oven, it will cling to the edges of the enameled walls and mica plate during rotation, gradually damaging them. That is, sooner or later with this approach, you will have to not only change the mica, but also paint the oven from the inside.
• The same thing can happen if the dishes are tall. It is less stable during rotation, so it can “fidget”.
• If the microwave oven is installed not clearly horizontally, but at an angle (even very small, sometimes invisible to the eye), when heated, any dishes will “travel”, clinging to the enamel.

What to do if the mica plate in the microwave burns out?

So, if crackles are heard when the microwave is turned on, sparks or even electric arcs are visible - most likely, the mica plate burned out. The first thing to do is turn off the oven and take care of acquiring a new lining. Also, for work, you will need sandpaper, a clerical or similar knife, and special enamel for damaged areas of microwave ovens.

We are not in a hurry to call the master - the lining replacement at home can be done independently.

When purchasing mica, ask the seller for all quality and safety certificates to be sure that you will not harm your health.

It is also necessary to change the plate if the too-clean hostess, tearing the stove to a shine, tore off the protective layer from the mica screen (as a result, the plate is deformed and malfunctions), if traces of soot are visible on the surface of the plate (even in the absence of holes - soon and they will appear). Well, if the holes have a diameter of more than 5 mm - we change immediately!

How to replace mica with your own hands?

First, turn off the stove from the mains. After that, follow this pattern:

1. Remove the damaged pad, depending on how it is attached: to self-tapping screws or plastic latches.
2. Thoroughly rinse the damaged plate to remove any residual contaminants (otherwise they will fall onto a new one when cutting, which can cause its quick breakdown).
3. Now attach the removed overlay to the new plate and cut the figure on this “pattern”. Use a wallpaper, clerical or boot knife to cut - their blades are thin and sharp enough for such work.
4. Punch holes for fastening with an awl or punch with a drill of a suitable diameter.
5. Strip the edges of the resulting workpiece with emery cloth to eliminate bumps.
6. Now the new part needs to be washed and dried to remove the remnants of dust settled during the cutting process.
7. While it is drying, completely degrease the inner chamber of the microwave oven. Especially carefully - in the area of ​​the protective mica screen.
8. Remove the magnetron (shortly before doing this, short-circuit it and the capacitor to remove the residual charge), inspect. If not only the cover plate, but also the protective cap of the microwave generator has burned out, replace it too.
9. If, during the burning of the mica plate, gaps formed under it, clean them with sandpaper and paint the damaged enamel.
10. When all parts have dried, install a new overlay. It will not be difficult to install it, since the location of the old one is clearly marked. This is either a special pocket fastened with a screw in one corner, or metal “tongues” on the case to the size of the plate. In the second case, it will have to be slightly bent so that it snaps into place.

When all work is completed, you need to make sure that everything is done correctly and the device is functioning again, as before. To do this, the oven must be turned on, having previously placed inside some kind of moisture-containing product (at least a bowl of water).

Do not use scissors to cut a new plate. Mica is a material that looks like pressed fine crumbs. Therefore, it is preliminarily applied to a thin but strong base. Scissors simply crumble its edges, and the workpiece will have to be thrown away.

How can I replace mica in the microwave?

If for some reason a new mica plate was not at hand (could not be acquired or there is no time for this), you can replace it with another suitable material. Which one? Today, even in professional workshops, heat-resistant food grade plastic is often used instead of mica. It is safe for human health, has qualities similar to mica, but it is much stronger, which means it will last longer. In addition, food grade plastic is lighter and more convenient to use.

Nevertheless, experienced repair technicians advise not to be smart, but to purchase mica specially designed for this purpose.Because the "native" is always better and more reliable.

Micas in the microwave are an essential element. Without it, it will not work (in any case, it is safe), therefore, it is impossible to turn on the oven if the mica screen is damaged, and even more so if it has already been removed for replacement. Accordingly, fragile, but necessary protection is important to protect. The tips above will help with this. So, it will not be soon to replace the mica pad.