Sears microwave does not heat

My Kenmore 721.63259301 would not heat items up so I came here and saw the parts required and was just about to order them when I checked the online owners manual and found this. FULL FIVE-YEAR WARRANTY ON
THE MAGNETRON For five years from the date of purchase, if the
magnetron in this Kenmore microwave oven
fails due to a defect in material or workmanship,
Sears will repair it free of charge.
My microwave has a manufacture date of July 2009 so I will be taking it right to the closest Sears repair center for a free repair. I suggest everyone do the same.

Hi and welcome to FixYa. I am Kelly. The majority of the time when you have a working control panel and no heat there are 2 - 3 items that fail.

Service manual for this microwave is actually posted on the sears website:
http://www.searspartsdirect.com/partsdirect/part-model/Sansui-Parts/Microwave-Parts/Model-MW8554W/1763/0123245?pathTaken=


Cost will depend on what part has failed.

Kelly

Micorwave doesn't work when the megatron tube is out. That's probably why it won't heat up. Either replace microwave or the tube. You can get the number from Sears for the megatron tube by calling customer support.

My Kenmore 721.63259301 would not heat items up so I came here and saw the parts required and was just about to order them when I checked the online owners manual and found this. FULL FIVE-YEAR WARRANTY ON
THE MAGNETRON For five years from the date of purchase, if the
magnetron in this Kenmore microwave oven
fails due to a defect in material or workmanship,
Sears will repair it free of charge.
My microwave has a manufacture date of July 2009 so I will be taking it right to the closest Sears repair center for a free repair. I suggest everyone do the same.

That model number's not showing up at the Sears site.

I would suspect that with everything you've said, it's the magnetron.

It should have a magnetron warranty of 5-9 years.

You may want to contact Sears Service to see.

Good luck.

If this is and Over the Range micro, the exhaust fan needs to run ANYTIME the cooktop is on. They make things for quantity and not quality, so the plastic has little tolerance for heat. Running the fan, diminishes heat off the front of the unit. Also, the micro MUST be at leat 24" off the cooktop.

This is probably a shorted triac or relay.

You can find exploded views and order parts by entering your model number at the Sears parts site.

There may also be a "mini-manual" (tech sheet) hidden inside the unit behind the control panel or hidden on the left side behind the grille, which is very helpful when troubleshooting, testing, and locating components.

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

Here are some links you or someone you know can use (in order given) for test help, but read the safety warnings first:

http://www.gallawa.com/microtech/diode.html (if it is NOT shorted, it's probably fine)
http://www.gallawa.com/microtech/mag_test.html
http://www.gallawa.com/microtech/xformer.html

There should also be a "mini-manual" hidden inside the unit behind the control panel or hidden on the left side behind the grille, which is very helpful when troubleshooting & testing.

Your biggest suspects will be a bad connection or relay on the control panel, a bad connection on the magnetron terminals, a bad magnetron, a shorted high voltage rectifier diode or a bad high voltage transformer.

You can find exploded views and part numbers by entering your model number at the Sears parts site.

A full Sears/Kenmore model number has 3 digits, a dot, then 8 more digits, such as ###.########

You may be able to find better part prices than Sears here.

Your magnetron may have a 5-9 year warranty, so check your manual for that. Sears may send you a magnetron if it's bad and warranty.

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

Since it's under warranty, they will replace or repair it at their choice, and if they replace it, it will be the same model or a "like model".

I'd ask them about it.

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

It's probably a shorted high voltage rectifier diode.

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

You can probably find an exploded view by entering your FULL model number here: http://www3.sears.com (the 3 is correct)

You can order Sharp parts from the Sears link above or from Tritronics at http://www.wehaveparts.com
We're happy to help and we appreciate your thoughtful rating of our answer.

If you need more help, please feel free to conact me directly through the links at our site.