Help with Microwave

deltamaster wrote:
Oh, I taped the extra fuse to the inside of the cabinet cover so if it happens again I am ready to go!

Great idea. And it also works for receipts on many items.

The fuse in question is either a 15amp or a 20 amp ceramic fuse available at Lowes or Home depot. If changing the fuse fixes it, then you are good to go. However, it doesn't always fix it. There are 3 or more thermostats, door switches, a diode, a cap, a control board, a transformer, and a magnetron tube that could also be your problem. If you have a volt meter, these componets are easily checked. There are several good U tube videos that will show you how. Just be careful to discharge the cap before messing around in there as it can store enough juice to kill you.

If your problem turns out to be a thermostat, switch, diode, or cap, these are easily and cheaply replacable. Anything else, I would be looking for a new microwave. Since it died while you were cooking, my bet would be a thermostat.
Big Bob

It's a $100 microwave, buy a new one.

deltamaster wrote:

Oh, I taped the extra fuse to the inside of the cabinet cover so if it happens again I am ready to go!

I agree with everything in your post, Except taping the fuse inside the cabinet. Tape gets old and loses it's adhesive properties. And you go driving down a bumpy road and the fuse in loose inside the cabinet. The last thing you want is for that fuse to get loose and cause a short in your electronics possibly causing a fire. Find a better place for your extras.

falconman wrote:
It's a $100 microwave, buy a new one.

Certainly a viable option if using tools is not your thing, however, if you can turn a screwdriver and you are fairly intelligent when it comes to respecting electricity (remember the unit is unplugged so all you have to worry about is the capacitors) then the savings is worth it.

Sure would be a shame to spend another hundred on a new unit when a half hour of tool time and a three dollar part would get it going again.

Mine is a Microwave/convection oven as I have no gas oven in my rig so it would cost much more than a hundred to replace.

Microwave ovens are relatively dangerous to work on. The power supply for the magnetron is capable of supplying a few thousand volts at significant currents—certainly enough to be lethal. The high voltage capacitors are typically wired with some sort of a bleeder to discharge them when the oven is off, but especially with an oven that's known to be having some difficulties it's quite unwise to rely on that. That's not to say that one cannot repair one's oven safely—just that it's vitally important to have a little bit of information and exercise due caution.

There are a few things that commonly cause the main fuse in the oven to blow: door safety switch problems (either from the door getting misaligned, junk building up on the switch, or the switch itself going bad), a shorted magnetron, and just plain old age of the fuse. If a replacement of it makes the oven work, it's probably the last one on the list.

There's a quite comprehensive and understandable guide to microwave oven repair including good safety information here.

DrewE wrote:
Microwave ovens are relatively dangerous to work on. The power supply for the magnetron is capable of supplying a few thousand volts at significant currents—certainly enough to be lethal. The high voltage capacitors are typically wired with some sort of a bleeder to discharge them when the oven is off, but especially with an oven that's known to be having some difficulties it's quite unwise to rely on that. That's not to say that one cannot repair one's oven safely—just that it's vitally important to have a little bit of information and exercise due caution.

There are a few things that commonly cause the main fuse in the oven to blow: door safety switch problems (either from the door getting misaligned, junk building up on the switch, or the switch itself going bad), a shorted magnetron, and just plain old age of the fuse. If a replacement of it makes the oven work, it's probably the last one on the list.

There's a quite comprehensive and understandable guide to microwave oven repair including good safety information here.

Another thing that can cause the fuse to blow is unreliable camp site power which is what I suspect caused mine to blow. We were hosting at a camp ground where the only powered site was for the host. There was only one pedestal and we had to share with the other host. I suspect that in the sharing process there was an errant surge when the microwave was turned on and the fuse protected the unit as it was intended.

YES due caution is imperative when working on electrical units but with due care a fuse can be easily and safely replaced.

The video I linked in previous post was a little sketchy on the safety aspect. The guy was poking around with a screw driver and used a metal screwdriver to pry the fuse out.

It would have been much better if the guy had kept the screwdriver away from "Stuff" and used a pair of rubber-handled (or even plastic) pliers to remove and replace the fuse. Aside from that the procedure is quite simple and can be easily done by someone that knows how to use tools and respects electricity.