What happened to my microwave?

Demo24

Diamond Member
Aug 5, 2004
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Recently I've noticed a difference in sound when using the microwave, but wasn't sure what was going on. Then the other day I noticed a flash of light inside and that's when I realized something far greater was wrong. Even more recently I looked in and realized that it was actually burning a hole through this one part pictured below and catching on fire. :|

Pic:
IMG_20111024_130730-7.jpg



In using it today I watched it closely and watched that hole in the top grow larger and flames came out, then at one point it started violently flashing above that plate. That's when I quickly turned it off. Now it doesn't happen everytime, but getting more frequent and it's obviously no good so I ask ye ATOT what just happened? Btw, microwave is like 15yrs old but it's worked flawlessly until now.


And yes it's kind of dirty in there, deal with it :colbert:
 

Demo24

Diamond Member
Aug 5, 2004
8,356
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15 years old? How long does it take to heat stuff in there?

Not that long, it works quite well unless it's catching on fire. :biggrin:


Food particles catching on fire. Clean the freking thing.

I thought that to, but I did clean the metal plate and there isn't anything on it. It's coming in from above and literally burning a hole through the metal.
 

PsiStar

Golden Member
Dec 21, 2005
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Food particles catching on fire. Clean the freking thing.

Thanks!


Sigh, time to go search for a new one. :\
I know of two 15 y/o microwaves still in good operation. The accumulated crap on the walls also absorbs energy. Burned holes in the wall are no surprise.

So, yes, *now* you need a new microwave. But, if you had just sterilized the kitchen sponge every couple of days in it and then wiped down the inside of the microwave ... you wouldn't be posting this.
 

Demo24

Diamond Member
Aug 5, 2004
8,356
9
81
I know of two 15 y/o microwaves still in good operation. The accumulated crap on the walls also absorbs energy. Burned holes in the wall are no surprise.

So, yes, *now* you need a new microwave. But, if you had just sterilized the kitchen sponge every couple of days in it and then wiped down the inside of the microwave ... you wouldn't be posting this.


I do so every so often, the flash made it look significantly worse than it actually is. However as I mentioned earlier there wasn't anything on the metal plate which it burned through.
 

PsiStar

Golden Member
Dec 21, 2005
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the "flash" from the microwave ... and depending on what was in it at the time ... is pretty telling.

Not doing any web searches to help refresh my memory, but I vaguely remember reading about things that can cause a flash ... aka arc over ... hmmm, did you have any kind of metal in it at the time? And, I am too lazy at this instant to look back over the thread as you might have said this, but is it taking longer to heat things up, significantly?
 

Demo24

Diamond Member
Aug 5, 2004
8,356
9
81
the "flash" from the microwave ... and depending on what was in it at the time ... is pretty telling.

Not doing any web searches to help refresh my memory, but I vaguely remember reading about things that can cause a flash ... aka arc over ... hmmm, did you have any kind of metal in it at the time? And, I am too lazy at this instant to look back over the thread as you might have said this, but is it taking longer to heat things up, significantly?


Nope, no metal. The flashing was contained above that metal plate, the hole basically starts to glow red then eventually flames will come out. I tried to get a pic for ATOT, but it stopped doing it and I don't really feel like turning it back on. And no reduction in performance.
 

PottedMeat

Lifer
Apr 17, 2002
12,363
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Nope, no metal. The flashing was contained above that metal plate, the hole basically starts to glow red then eventually flames will come out. I tried to get a pic for ATOT, but it stopped doing it and I don't really feel like turning it back on. And no reduction in performance.

that's not a metal plate covering the waveguide - it's mica or something microwave transparent. it's just there to keep food out. take off the plate and see if there's something on the other side. there really shouldn't be any way for gunk to get on that side but who knows.
 

Modelworks

Lifer
Feb 22, 2007
16,240
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It is a mica cover for the waveguide. It is there to prevent food from getting into the magnetron. You can replace it yourself . There isn't anything brand specific about it, you just need one the same size or cut one to fit.

They cost about $5. Search for wave guide cover. The reason it arc'd is because it got damaged and sharp edges developed. Microwaves like to build up and reflect on sharp object, the reason why metal often arcs. Aluminum foil is microwave safe, IF you are careful not to have sharp edges. Used to do it all the time to defrost things like chicken without overcooking.
 

Demo24

Diamond Member
Aug 5, 2004
8,356
9
81
It is a mica cover for the waveguide. It is there to prevent food from getting into the magnetron. You can replace it yourself . There isn't anything brand specific about it, you just need one the same size or cut one to fit.

They cost about $5. Search for wave guide cover. The reason it arc'd is because it got damaged and sharp edges developed. Microwaves like to build up and reflect on sharp object, the reason why metal often arcs. Aluminum foil is microwave safe, IF you are careful not to have sharp edges. Used to do it all the time to defrost things like chicken without overcooking.


Good to know, but where would I find such an item?