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Microwave Help

Microwave Help

Microwave Help

I guess I posted my thread in the wrong forum and then my thread got deleted. I was just hoping that instead of deleting my thread the mod could have move the thread to the right section of the forum, because I guess a lot of us here sometimes missed read, time consuming, not knowing, etc. Anyway, just some excuses. Hope Mods here don't get mad easily :) cheers!

I have a microwave when I plugged in the to the wall socket, I didn't get any power. I openned it out and checked, I found the fuse was blown. I replaced another the fuse with the same amp.  voltage, I'm back in business again. I tested and it was running fine as expected, but as soon as I open the door cover, the fuse is gone. Tried a few more fuses in diff wall socket & locations, the same results. Does anyone here have experience or knowledge about microwave, please help. I thank you in advance.

RE: Microwave Help

Frequently, older microwave ovens do blow the fuse - more of a fuse-fatigue issue. Replace the fuse and they're good for a few more years.

Other than that, what usually fails first (other than the control panel) is the large capacitor associated with the transformer/magnetron. Looks usually line a motor-run capacitor. I don't recall exactly how this capacitor is located/used within the circuit.

Microwaves are inexpensive enough you might just recycle the old one and get another.

RE: Microwave Help

I have another thought.
When you open a door, there is a safety interlock that is supposed to turn off the rf power before you get the door too far open. So that energy doesn't leak out and hurt people (plus screw up 2.4 ghz phone calls).

If the interlock on the door (mechanical switch inside a slot near the door) has a screw that loosened, then RF might not turn off as you open the door, this reflects alot, and could blow the fuse. It doesn't sound like a great answer, but something to look at. My oven had 3 interlocks to turn power off, two on the door, and one on the back cover.
Look to see if you can see a screw, or recall if the door opens a bit before it's power turns off.

It might just be the on/off circuitry has failures too. Tougher to fix.

Also, I had a microwave that had a spring on the door that extended inside next to the fuse. When that spring broke, it blew the fuse. If you have a spring on the door, when you open it, look inside the oven's guts, next to the fuse and see if there is a spring on the door that can touch anything that might blow the fuse. If so, add a plastic protector to the circuitry.

Good luck.

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