20 Most Recent Thermador MBBS Microwave Oven - Page 4 Questions & Answers

HI. Your symptoms are a strong indication Magnetron failure. This is the principal heating device, that is used to produce microwaves that , essentially, excite the water molecules in the food, thus, producing the heating effect. When this device fails, generally, the unit will run, but not heat. This device is very fragile, and can injure you if you are not qualified to handle this type of component. There is a High Voltage Capacitor, that is used to help provide the necessary current for optimal Magnetron operation. This capacitor must be discharged correctly. If not, you could risk serious injury, during the repair, if it is accidental touched.

The Magnetron is linked to a cut-off fuse. If the magnetron becomes unstable, this fuse will shut the device down. It is standard procedure to have this fuse test for continuity. If the fuse has blown, this will be the culprit. Replace the fuse. Now, if the fuse continues to show continuity, this will confirm that the Magnetron has failed. I would advise to inspect the Capacitor, and HV diode for visible burn marks, or swollen top(Cap).

Access can be ac hived to these parts by removing the outside cabinet screws. Once the screws are removed, the cover can be removed, as well. Once the cover is removed, the internal components will be exposed for testing, and visual inspections.

WARNING: IF YOU ARE NOT A QUALIFIED SERVICE TECH, THIS WILL NOT BE A NOVICE DO IT YOURSELF JOB. MICROWAVES ARE VERY DANGEROUS, AND CAN CAUSE SERIOUS INJURY. I RECOMMEND TO CALL FOR SERVICE, IF YOU ARE UNCOMFORTABLE WITH HANDLING THE CAPACITOR, OR MAGNETRON.

The loud noise is probably the magnetron makign the noise. The charred areas on the wall are from possible grease or food particles arching and burning the cavity. Alot of times there is a cover on the wall it burns. it would need to be replaced, as well as sand and paint the cavity area that is damaged with m/w grade paint.

I have found the main cause for this problem is a magnatron assemble that is becoming faulty. I advise changing the Magnatron. Good Luck.

You may want to look into the possibility of a "panasonic" (specifically a "genius" model) microwave unit that should fit there nicely. most of those Thermador 3 component units had the m/w built by panasonic. (though you'll not get them to tell you that)

I'd like to add, I find it unlikely your's is "burned beyond repair". what is the problem, if you'd care to elaborate.
Perhaps your m/w can be saved, or revived.

easy...first thought it was a program glitch. turntable could be turned off manually. nope ...just a bad motor needed replacement

Sounds like the thermal protector on the mag tube quit. It may have gotten too hot and opened up. That is the lesser of all the evils that can happen to a Microwave.

When the microwave sounds okay, but there's no heat, one of the internal door switches, the high voltage circuitry, or the circuit board may have a problem. To resolve this problem, you need the assistance of a qualified appliance repair technician.
I strongly recommend the techie because teh high voltage circuitry in there will still get you even when the unit is unplugged.

This is usually just due to grease or food particles stuck somewhere in the cavity of the oven or stuck on or behind the waveguide cover.

The waveguide cover (also called a spatter shield) is usually about the size of a playing card and often held in place by a plastic rivet.

It can be fragile, and the metal edges of the oven behind it can be sharp, so be careful!

The cover and the metal behind it should be cleaned with a mild, non-ammonia cleaner.

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 places like Wal-Mart, Lowe's or Builder's Square.

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

If so, please double-check your model number on the tag so we can help you better.

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

Quite often this is due to grease or food particles stuck to the inside of the oven or stuck on or behind the waveguide cover.

The waveguide cover is usually about the size of a playing card and held in place by a plastic rivet.

It can be fragile, and the metal edges of the oven behind it can be sharp, so be careful!

The cover and the metal behind it should be cleaned with a mild, non-ammonia cleaner.

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

Then you can apply some high-temperature appliance paint, available from places like Wal-Mart or Lowe's.

If your waveguide cover is burned, it will need to be replaced.

Normally you have to separate the door panels (as shown in the attached photo) and then you'll see the previously hidden screws you need to remove.

Or you can watch a YouTube video (not a video I made) that demonstrates how it's done.

You can usually find helpful exploded view diagrams and order parts by entering your full model number here.

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

Proberly wave guide cover at side it can get grease behind it,And when you used it with small load it tried to cook it and then burned the mica cover,Take mica cover off and try it without it to seeif problem resolved if ok,New cover can be obtained if req.Regards grandadfixer

You can usually find helpful exploded view diagrams and order parts by entering your full model number here.

Normally you have to separate the door panels (as shown in the attached photo) and then you'll see the previously hidden screws you need to remove.

Or you can watch a YouTube video (not a video I made) here that demonstrates how it's done.

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

Quite often this is due to grease or food particles stuck to the inside of the oven or stuck on or behind the waveguide cover.

The waveguide cover is usually about the size of a playing card and often held in place by a plastic rivet.

It can be fragile, and the metal edges of the oven behind it can be sharp, so be careful!

The cover and the metal behind it should be cleaned with a mild, non-ammonia cleaner.

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 places like Wal-Mart, Lowe's or Builder's Square.

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

You should be able to order one here.

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

Normally on over the range models, you would unplug the oven from the wall, remove the 2 or 3 screws holding the top grille in place, remove the screw at the top of the control panel frame, then CAREFULLY lift up and out to remove it.
If it is a counter top model, you need to remove the outer cover before remoing the control panel frame.

If you can give us the full model number from the sticker, we might be able to give you more specific help.

If you or a friend decide to work on it, we have *critical* safety, disassembly, and troubleshooting info at our site, which is linked at our listing here on FixYa: http://tinyurl.com/yzjozk

The manual for the MBES may be close enough:

 

http://www.thermador.com/site_tools/documents_3.aspx?product_id=68

 

Otherwise, you can contact Thermador:

http://www.thermador.com/about_us/contact.aspx

The transformer that supplies the magnatron is fed from the same part of the machine that feeds the turntable motor. The turntable motor is fed through one of the door safety switches. Check the door switches and feed fuse. If a diode pack has failed, that will blow the fuse or even damage the switch as well.

That is a funny looking unit! You know we are Fixya and not Thermador right? There must be too much heat back there and it is over heating the socket and the microwave lead which isn't heat resistant and normally only has its own heat to contend with. What I would do is pull all that appliance out an put it on the other side to the kitchen, and ask a bigger electrical contractor to MOVE and REPLACE a pair of outlets in a kitchen for a remodel. What I would do is to certainly move the microwave outlet to the cupboard next door. Make a decision whether to move to 220 oven outlet as well. Don't mention anything about burning plugs or the 87 volts. Tell them you would like Industrial Quality Outlets and not domestic. I reckon that will fix the problem.

Just measure width and height of what you can see at the front. They are all standard sizes for built in units. Your installer will make it fit the framing at the back. https://www.google.com/search?q=Thermador+%2216-10-585%22 ..