Question about GE JVM1870 Microwave Oven

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GE JVM1870 Runs, but won't heat up

Some advice that I have received has been that the magnetron, high voltage capacitor, or diode could be bad. Another person in this forum suggested that I check the fuses. After disconnecting the power I have partially disassembled the MWO (microwave oven). I do see two fuses - "Main Fuse" and "HVT Fuse" (High Voltage Transformer?). According to the factory schematics/parts list both fuses are 20A 65TL. Which one do you think could be causing my no heating issue? Should I replace them in any certain sequence? Any other concerns that I should be aware of prior to trying to fix the problem myself? At the end of the day... I can't/don't to afford to 1) buy a new MWO as some have suggested or 2) pay extremely high repair charges for a factory repairman regarding a hopefully simple problem that I could fix. Any help that you could provide would be greatly appreciated as my wife is getting upset that she has not been able to use her MWO for a couple of days now.

Posted by Rick Proctor on

  • 1 more comment 
  • Anonymous Nov 03, 2007

    Everything on my MWO works except it doesn't heat up.

  • JayMan152 Nov 12, 2007

    Is it worth repairing or would it be better to buy a new microwave?

  • Anonymous Jun 30, 2008

    I have a samsung mivrowave oven. I runs as normal with the normal humming sound but it wont heat up the foods.Is this a problem I could fiux myself? Do magnatrons usually give problems as I also have a GE unit which does not work at all.



2 Answers

William Miller

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If you or a friend decide to work on it, we have *critical* safety, disassembly, and troubleshooting info (as well as a text file which helps in diagnosing and repairing door switch problems) at our site, which is linked at our listing here on FixYa: You can find helpful exploded view diagrams and order parts by entering your full model number (without the suffix) here:

Posted on Apr 10, 2007


Henry Thomas

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My brother check the magnetron and the high voltage cap they are bad.or you got to take your microwave to a tech replace both component.good luck.

Posted on Apr 03, 2007


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