Question about Panasonic NN-P794SF Microwave Oven

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Microwave turns off after 10-15 seconds.

My microwave turns off after ten-15 seconds. Everything in the control panel works fine. The microwave will run if set under 50%, but nothing gets hot.

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  • chris bean
    chris bean Nov 22, 2008

    The fan runs, and the time it takes to turn off depends on the power setting. The higher the setting, the quicker it turns off. Also, the fan sound as if it's speed is inconsistent, like the power to the fan is fluctuating, seems like something is trying to draw power and causing the fan to slow. I am eventually going to tear into it, but I although I am familiar with capacitors and high voltage, I don't know what sensors or switches may contribute to the turning off. I basically need to know where to start.

  • chris bean
    chris bean Mar 29, 2010

    Thank's for the info. more than likely the sensor model, stainless steel mic with more programming option than my computer. we moved and it got thrown into storage before I could check it out, just pulled it out the other day, I am going to check it today. If I remember correctly it stops right around 16 seconds, won't make it to 22.



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Make sure you hear the fan is still operating in your microwave. Next is to make sure the air intake grill on your microwave is not plugged up with air borne dust and dirt.

for heating problem
Many thing can do this but, common things are....loose high voltage wire.....poor solder joint on board.....magnetron.....power relay

Posted on Nov 13, 2008

Testimonial: "first suggestion pointing out the possibility of a plugged vent. Such a simple idea, yet noone ever considers it."

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If it stops at 16 seconds and is a sensor model, it probably has a defective humidity sensor.

Ifit stops after 22 seconds, that means the controller has detected aproblem, usually a problem with the inverter or a bad magnetron.

Due to the lethal voltages used and produced, I do not recommend that an inexperienced person work on these.

You can find an authorized Panasonic servicer here.

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

Posted on Nov 21, 2008

Testimonial: "Ok, I may be able to buila a hi-volt inverter, I have a friend who does windings for transformers... I will look into that"

  • William Miller
    William Miller Nov 23, 2008

    Okay, that would be a problem with the high-voltage inverter or the magnetron.

    You're right, it is what's called a loading effect due to a failing component.



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