How can I tell if my microwave oven is unsafe?

[Ted Shoemaker]

Hello,

Our microwave oven has been sparking intermittently.

On the inside wall of the oven, (i.e. in the food area) is a shield
made of sheet metal, about 2 inches by 4 inches. The sparking has
occurred at the top center of that shield. Now there is a small hole
at the sparking site, about 1/8 inch across.

How safe (or unsafe) is this oven? Is it fixable?

Thank you very much!

Ted Shoemaker

 

[Mistress]

On the inside wall of the oven, (i.e. in the food area) is a shield
made of sheet metal, about 2 inches by 4 inches. The sparking has
occurred at the top center of that shield. Now there is a small hole
at the sparking site, about 1/8 inch across.

How safe (or unsafe) is this oven? Is it fixable?

"Safe" is a subjective judgement. It is fairly obvious that this condition
needs to be fixed. I would recommend not using the unit until it is.

I am trying to guess what the piece may be. Are you sure it is metal? (The
size and placement lead me to think it might be a difuser; mentioned in my
response post a couple days ago)

If it is metal, are there screws securing it to the other metal? If so, try
removing the piece, cleaning the goop off it and securely replacing it. A
metal part must be securely connected to the cabinet wall. Of course the
new hole in it suggests you should replace the part anyway.

These are only long-distance guesses. Good luck.

 

[Just Me!]

"Safe" is a subjective judgement. It is fairly obvious that this condition
needs to be fixed. I would recommend not using the unit until it is.

I am trying to guess what the piece may be. Are you sure it is metal? (The
size and placement lead me to think it might be a difuser; mentioned in my
response post a couple days ago)

If it is metal, are there screws securing it to the other metal? If so, try
removing the piece, cleaning the goop off it and securely replacing it. A
metal part must be securely connected to the cabinet wall. Of course the
new hole in it suggests you should replace the part anyway.

These are only long-distance guesses. Good luck.

think it was my post you refer to, yes indeed a diffuser(in my case),
developed slight hole and started arcing, removed it cleaned it off both
sides and replaced as securely as it was. Now works fine but has small
hole through middle, does this mean the micro part is now focused
through the hole and not diffused, if so is there any danger to anyone
using it? its a combi and the oven is used more than the micro

will replace as soon as I can find someone that knows what I am talking
about

HTH OP
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[Mistress]

Now works fine but has small
hole through middle, does this mean the micro part is now focused
through the hole and not diffused

Good question. I have no idea what effect the hole would have.

Maybe the lurkers can come up with some truly diabolical experiments to
determine the new diffusion pattern.

 

[Sam Goldwasser]

think it was my post you refer to, yes indeed a diffuser(in my case),
developed slight hole and started arcing, removed it cleaned it off
both sides and replaced as securely as it was. Now works fine but has
small hole through middle, does this mean the micro part is now
focused through the hole and not diffused, if so is there any danger
to anyone using it? its a combi and the oven is used more than the
micro

will replace as soon as I can find someone that knows what I am
talking about

As far as I know, it's just cover for the waveguide and doesn't affect
the distribution of microwave energy in any way. The turntable or
rotating paddle distributes the microwaves more evenly.

Also keep in mind that the wavelength of the microwaves is about 5
inches. They don't sneak through little holes.

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[Sam Goldwasser]

Good question. I have no idea what effect the hole would have.

Nothing at all. 2.45 GHz (5 inch) microwaves won't go through a 1/4" hole.

But that's even irrelevant since the plate is most likely just an inert
waveguide cover, not a "diffuser".

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Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header is ignored.
To contact me, please use the feedback form on the S.E.R FAQ Web sites.

 

[Jerry Greenberg]

Personaly I would have the microwave oven properly checked by someone
who is experienced at servicing them. If you have something that is
sparking, there is definately something wrong. The sparking means that
something is conducting to itself or ground, and acting as a load.
This can damage the magnetron after a period of time.

If you are cooking, and there is sparking, the sparks can be releasing
some fumes due to the breakdown of the material being arced. This may
not be safe for the food, depending on the material composition that
is arcing.

As for radiation safety, this depends on how well sealed the cabinet
and doors are. This can be properly checked with a microwave oven
radiation meter.

Any of the service centers that service microwave ovens can check this
for you. If your oven is a low cost oven and it is out of warranty,
and you do not have the experience and skills to service it yourself,
you may be better off to get a new one if the service cost will be
high. First, take it in to the service center find out what is
involved.

Jerry G.
========

 

[Ted Shoemaker]

Thank you for all answers.

Ted Shoemaker

 

[CSA722]

Had the same thing happen to an old Emerson microwave. It was just a waveguide
cover held on by plastic snaps. Grease had made its way around the edges and up
over the top of it and thats what burned and caused a hole. A nearby appliance
store had a new cover. Cheap.

 

[Harry Hotspur]

It's the wave guide cover,needs replacing before working the oven again.
Some models[Matsui etc] have metal waveguides,others have the more easily cut
foil lined cardboard guides.
Metal you need the original part replacement,foiled cardboard you can buy a
sheet and cut[carefully] to shape. Either way it should be a cheap repair.