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Kenmore 81682 Won't Heat

I have the Kenmore 81682 Over the Range Microwave Oven. Two weeks ago it stopped heating. I opened it up and the magnatron was cracked in a few places. I located and replace the magnatron (part number 2M289-M47) and it works without an issues for about a week. Today, it stopped heating again. I opened it up and the magnatron is cracked again. Before I replace the magnatron again, what else can I check? What would be causing the magnatron to fail?


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  • stuff734 Dec 19, 2008

    The crack is on the bottom magnet inside the magnatron. I can check the cooling fan to ensure that it is running while the microwave is on and get back to you.


  • stuff734 Dec 19, 2008

    I fired the microwave up this evening and the cooling fan does come on when the microwave is started. It draws cooling air through a squirrel cage type fan. Any other ideas on things to check?


  • William Miller
    William Miller May 11, 2010


  • William Miller
    William Miller May 11, 2010

    The only causes of cracked magnetron magnets that I know of are some kind of odd mechanical stress or overheating.

    An overheating magnetron can be due to:

    - operating oven without cover(s) in place

    - wrong magnetron installed in oven

    - an old or otherwise failing magnetron

    - cracked magnetron magnet

    - improper power line voltage (should be 110-125VAC)

    - foods low in moisture (popcorn & bacon, e.g. - add 1/2 cup of water in rear oven)

    - failed or inoperable cooling fan or hood vent exhaust fan

    - deteriorating foam weatherstripping seals in air ducts or on outside cover

    - blocked air vents (dust, animal nest debris, insufficient free air space behind & around oven, etc.)

    - clogged or greasy charcoal filter or grease filter

    - blocked duct in hood vent exhaust

    Once you look these over, let us know what you find.

  • William Miller
    William Miller May 11, 2010

    Where is it cracked? The antenna at the top or the magnet inside the cooling fins?

    Is the cooling fan running when you cook?

    When I say internal
    cooling fan, I do not mean the hood vent exhaust fan which you can turn
    on and off manually.

    I'm instead talking
    about the internal fan which comes on automatically whenever you

    It is vital that the
    cooling fan runs, or the magnetron will be destroyed.

    When the magnetron overheats, the magnetron thermostat or thermal cutout should interrupt power to the oven. Curious...



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Posted on Jan 02, 2017

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SOURCE: don`t cook

try opening the case and checking the internal fuses. these normally cause the problem

Posted on Feb 21, 2009

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SOURCE: Kenmore microwave making loud buzzing sound.

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

Posted on Mar 06, 2009

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SOURCE: my over the oven model 665.61629100 kenmore has cracked door

The outer door frame CAN be replaced if you like. You can view an exploded view diagram at Just type in your model number and locate item 10 under the "Door" parts listing. The part comes in various colors so make sure you select the correct one.

The door can be easily removed by opening it all the way and lifting straight up at the hinges. The door will come off the hinge pins and can be laid on a flat surface for easier access. Place a layer of towels under the door to prevent damage to the door.

You will need to remove the door handle to get the outer door frame off. To access the door handle mounting screws on MOST microwave ovens, you have to remove the inner door panel that goes around the perimeter of the glass. You can use a small screwdriver to carefully pry the plastic up and work your way slowly around the perimiter of the glass. Most microwave ovens also have grooves in the panel that you can insert the screwdriver into. Use care not to pry against the glass. The glass is tempered and also has an RF shield that prevents harmful microwaves from potentially harming the consumer. If you break the glass, you may need to purchase a new door.

The door handle screws are located behind the inner panel. Remove the door handle and and locate any screws that may be securing the outer door (front) frame in place. Once you install the new outer door frame, re-install the door handle and carefully re-insert the inner door panel. Gradually work your way around the perimeter of the door glass and make sure it snaps back into place.

If you have questions about this repair, please let me know. I hope this helps you.

To answer your initial question, the microwave should continue to be safe to use as long as the inner door seal and door glass are intact. Make absolutely sure you reinstall the door components back together properly. Not doing so will render the oven unsafe to use. Refer to the web site I provided as a reference for how the door components go back together.

NOTE: This part is listed a bit cheaper at Use the part number from the first website I mentioned as your search criteria.

Posted on Jul 31, 2009

  • 672 Answers

SOURCE: i bought a used over the range microwave oven(

Most Kenmore microhoods use a 3" by 10" exhaust duct. Check for correct demensions. Make sure that the existing vent is this size or that you have room to adapt to this size. There should be a damper mounted to the top of the micro which will attach to the vent duct work. You will need an outlet in the cabinet above the micohood. This should be on a circuit of it's own. The microhood should have a wall plate for the back wall. I'm going to assume there are no templates available. Hold the wall plate against the back of the micro to determine the height placement in the opening. Most install centered under and against the cabinet above. Not all do, so this will confirm. Mount the wall plate to the existing wall studs with at least 1/4" by 2-1/2" lag bolts. Bore an 1-1/4" hole in the right rear corner of the cabinet above, about 2" out from the back of the cabinet and 2" in from the side, this is not a critical measurement, it is to pass the electric cord into the upper cabinet. There are two screws that support the front of the hood. I believe they are 1/4" by 3-1/2" long. If not included, check for size. The hardwae will have them, get flat washers to fit both also. Measure from the back of the micro to the mounting holes in the top of the micro, include the wall plate in this measurement, they'll be about 10" out from the back and about 1-1/2" in from the edge, near the front, but check that measurement, they vary. Drill 3/8" holes in the bottom of the cabinet at these locations. If doing this alone, best that you move the range out. It's nice to have a helper at lifting time. With the plate on the wall and the holes in the bottom of the cabinet, your ready. Put the 1/4" screws and someting to drive them in the upper cabinet, so they'll be available. Lift the micro into the opening with the front tilted downward, hook the back of it into the bottom of the wall plate, push the cord into the upper cabinet, tilt the front of the micro up until you can start the front support screws. Start both, don't let go of the micro until you are sure that both screws are started and will support the front weight. Once you're sure, tighten both screws all the way and connect the vent. Steel tape is best for sealing up any leaks. Power up the outlet, plug in the microhood and put in the popcorn. Get a good movie and enjoy in your accomplishment. Congrats. PS: Make sure the roof vent opens when the hood is turned on, I have seen them stuck shut from grease build-up.

Posted on Oct 22, 2009

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What happens is thjis: when the oven is running ane you open the door, the tiny contacts in these little swirtches arc and burn. Eventually, the switches fail. When this happens, the oven doesn't know the door is closed. When The door is open, the oven will not turn on the magnatron. No magnatron, no heat.

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Im sorry to hear you are having this trouble.

I believe you have a faulty door safety interlock switch. Please remove the cover and check the small micro switches with your ohm meter.

What frequently happens is this: because of opening the door during oven operation, the small points inside the switches arc and burn. Once they cannot make contact, they are not able to tell the oven the door is closed and when the door is not closed (forget what YOU think the door is doing) the oven will not turn on the magnatron. No magnatron, no heat.

Please let me know what happens

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