Can I post a weird electrical question here?

[John Stevens]

I hope this isn't the wrong forum to ask this question about an electrical circuit in my kitchen.

My garbage disposal suddenly stopped working. Flicked the switch, nothing--no hum, no burning smell, just nothing at all.

Checked to see that the disposal was spinning freely--it was. Couldn't see anything wrong inside or out, so decided to see if it wasn't getting electricity. Checked the circuit breaker on the underside of the disposal, but it hadn't tripped. Checked the circuit breaker in the breaker box in the basement, but that hadn't tripped, either.

The disposal is hard-wired, not plugged in to an outlet, so I got my circuit tester to see whether there was juice at the wall switch that turns on the disposal. Yes there was.

Then I went into the wiring connection for the disposal. Got an old extension cord that had the female end cut off, and connected the leads of the cord to the leads of the disposal. Plugged the extension cord to a wall outlet and flicked the switch. The disposal started right up. "Okay," I thought, "as unlikely as it is that a short suddenly appeared in the wiring between the switch and the disposal, that seems like the problem."

I decided to use my circuit tester on the leads coming from the wall switch. At first, I got nothing. The tester is the cheapest kind, with two prongs wired to a tiny light bulb, so I figured maybe I just wasn't making a good connection. I pressed the prongs of the circuit tester harder against the leads, and there was a tiny little flash of light in the tester, then it died. I moved the prongs of the tester back and forth on the leads, and the same thing happened. Weird.

Then it seemed as if the light bulb would stay on for a few seconds, but die out again. I shut off the power and sanded the ends of the wires, even though they didn't show signs of corrosion. Tried the circuit breaker again, but no change. Weird.

Then I got a flood light and connected the leads coming from the wall switch to the male prongs at the end of the cord of the flood light. At first, the bulb went on, but only very dimly. It then got just a tiny bit brighter, then slowly went back to very dim. This happened three or four more times over the course of 15-20 seconds. I watched it, just wondering what the heck was going on. There had never been a problem with this circuit, or any other circuit in the house. (We've lived here eight years and the wiring was re-done just before we bought the place.)

So as I'm watching the bulb in the flood light slowly go between very dim and a little less dim, it starts getting a little brighter, then brighter still, then finally it reached full brightness. All this took place in 60 seconds or less. There was no noise and no burning smell. Everything seemed normal, other than the weird behavior of the light bulb.

So at that point, I disconnected the flood lamp and re-wired the garbage disposal. Turned it on, and it worked fine, just like it always had. Tried it three or four more times over the course of an hour, and it ran as if nothing had happened.

So my question is--what was wrong? Is there still something wrong?

Thanks in advance for any educated guesses you can give me.

Regards,

John

[Ken Fitzgerald]

John,

It sounds like the contacts in the wall switch are going bad.

You don't have a short or you would be tripping the breaker.

Something is opening up the circuit and thus you aren't getting power to the disposal.

Based on what you have stated here, I'd try replacing the switch first.

It could also be caused by a loose connection somewhere.

[David Woodruff]

Intermittance should be a noun.

[Lee Schierer]

I agree with Ken, sounds like a bad switch or possibly the wire has gotten wet and is corroded or possibly broken internally some place between the switch and your test location. Check the rating on the switch against the nameplate amps on the disposal. Depending upon the size (Hp) of the disposal the switch may too light duty for the current draw on start up.

[Jim O'Dell]

If not the switch, where does the wire to the disposal come from? Other items on the same circuit? Could be a broken/loose wire at an outlet where this power comes from earlier in the circuit. I'd turn the breaker off, and test which other items are on that circuit. Start with the ones closest to the disposal and see if a wire is loose. Could be broken in the sheathing too, so don't overlook that possibility. I ran into that when I wired my shop. After getting the power turned on, I checked all the outlets. One lit the night light I was using as a tester very dimly. Found a wire broken at the previous outlet that was making contact, but wouldn't carry any amperage to run anything. Jim.

[Jim Koepke]

My suggestion for a person who does not know the difference between a short and an open would be to find someone who does and have them help you even if you have to pay them.

I would also think the garbage disposal should be on its own GFI circuit or breaker. There may be a junction box with a loose wire connection somewhere causing the problem.

jim

[Steve Schlumpf]

My suggestion for a person who does not know the difference between a short and an open would be to find someone who does and have them help you even if you have to pay them.

In the interest of safety - I totally agree with Jim! Get someone to come over and check for the electrical problem.