Problem with Sharp microwave/convection R-1874

[WheelingIt]

Hi everyone,

First post here so will start off by saying "hello" to everyone!!

We've got an issue w/ the microwave/convection in our 2008 Holiday Rambler 40PDQ. A few days back, as we were cooking the heat stopped working. Lights come on, oven "sounds" like it's running, but turntable doesn't turn and no heat. Had a technitian come look at it (before we figured out how to get the thing out) and he "thinks" it's the inverter board that's bad. So, a few questions for folks out there:

1/ Has anyone seem this problem or swapped out the board themselves? Is it a simple swap?
2/ I'm deathly afraid of the huge capacitor in the microwave...anyone know how long it takes that beast to decharge before I can safely go prodding around in there?
3/ Any other ideas or ideas WHY this might have happened? We have an external surge protector (always) on our shore power and can't figure out what could have toasted the board?

Sorry for the long, detailed post. Frustrated by lack of oven....

Nina

[Jackm]

If you can get an inverter board that can be returned (if it doesn't solve the problem), this might be your best option. It shouldn't be too hard to swap it out. As for how this happened, you know the old saying. It might simply be a bad board.

Capacitors generally don't discharge themselves. Most technicians use a rubber handled screwdriver to short out the terminals and subsequently discharge the capacitor. In other words, they place the screwdriver across the two terminals of the capacitor. It will cause a spark and make a noise but after that, it won't bite.

If you don't get a definitive answer on this forum, I would think long and hard about the logistics and cost associated with removing the unit and taking it into an authorized repair center. I say this because you can get a new 30" built-in microwave/convection oven (on sale) at places like Sears, Lowe's, and Home Depot for around $300.

Hopefully, the technician was right. That way, you may be able to fix it yourself and look like a real hero. If the technician was wrong and the swap doesn't fix it, get an estimate before bringing it into a shop. Best of luck and let us know how things work out.

Jack

[RV Wizard]

Hello Nina and . We are glad to have you join us here and we look forward to reading of your adventures and experiences. I am sure you will enjoy the website and forums. Good luck, stay safe and keep us posted.
When you say the heat stopped; is that the microwave or convection? Have you tried closing the door rather hard, in case a door interlock switch may have been stuck?

[WheelingIt]

Thanks both for your replies.

Jackm - appreciate the tips. It's an expensive oven (listed at $500 at Sears) so I'm hoping to fix before replacing, but I think your idea of a board that can be returned is a good one

RV Wizard - thanks for the welcome. It's BOTH the microwave & convection that stopped heating. Lights, timer, all other electronics work and it "seems" to run, but no heat and no turntable. And yes, I did couble-check the door connection (pushing it, etc to make sure it wasn't the problem), but no go on that one. Thanks for that tip.

[Old Blue]

Our micro stopped working last year, bought a new one at Walmart until we returned home,,than took it out tried it again nothing, lights etc. worked no heat, but it worked on convection, took it to an authorized dealer they checked everything and the thing worked,,,,never knew why it stopped or anything else,,we think it was just one of those things>>><?2007 Holiday Rambler Neptune PDQ
Bill

[butterbean]

Howdy Nina & WheelingIt,
You better check before you puchase a board, to see if it's returnable.. Most electric and electronic parts ARE NOT.. I'd also like to welcome you to the forum and make friends with you & your pets..
The problem with the microwave is it was made in China(isn't everything). I used to think the Chinese only used robots in their manufacturing, but found out the other day they still handwork a lot of their assembly.. The problem may be just a loose wire... Good luck with it and let us know..

[WheelingIt]

Thanks everyone for the tips & support. The microwave is in the storage bay at the moment and we're going to deal w/ it when we settle down for the winter in a few weeks in FL. Will let you know how it goes.

[WheelingIt]

Quote:

Originally Posted by WheelingIt Thanks everyone for the tips & support. The microwave is in the storage bay at the moment and we're going to deal w/ it when we settle down for the winter in a few weeks in FL. Will let you know how it goes.

Just want to let everyone know we finally fixed it! It was the controller board. So good for now. Thanks for the help.

[davecampbell]

PS I realize this problem is solved, but for safety sake - microwave ovens capacitors are DEADLY.

NEVER touch one unless you know exactly what youre doing. They charge to about 2200V DC with quite a current behind them.

Some have bleeder resistors across them. Screwdriver - its not that easy, the terminals are always plastic coated to prevent contact and it usually requires removing a terminal to short the cap, and thats dangerous.
It usually takes an insulated jumper wire or two screwdrivers.

I worked on these beasts for 10 years, one of them darn near killed me.

[WheelingIt]

Quote:

Originally Posted by davecampbell PS I realize this problem is solved, but for safety sake - microwave ovens capacitors are DEADLY.

The comment makes sense and I should have added that we ended up getting help on the capacitor from someone who knew. The capacitor was actually one of my biggest worries getting into this and in the end we decided not to tackle it alone. So, def appreciate the warning. Nina