I had the garage upgraded to 100 amps. The guys did a great job. I'm having another problem, but I didn't mention it to them until yesterday, and they didn't have much time to take a look. The problem is some of the lights in my house seem to dim ocassionally. This was happening before the garage work was done, so I doubt it has anything to do with it. When they dim, sometimes the computer shuts down, (it is on a surge protector), the clock on the range resets and so forth. My home is thirty-two years old, and has aluminum wiring. (Lucky me). I had a similiar problem a few years ago and an electrician from the power company opened up the meter tightened the lugs inside, (said it "single-phasing"?) and the problem went away. I thought maybe my problem was a bad circuit breaker, but not all of these items are on the same circuit. Does it sound like single-phasing? And if so, what can be done to keep them tight? Thanks folks!

Bill

Your main circuit breaker may have come lose and/or it is starting to arc thru the main bus bar. The lights dimming will be more noticable when you have are drawing a higher load.

Zinsco panels are notorious for this.

It sounds like you are having a single phasing problem and the likely areas to look are at the main breaker & bus bars as Andy indicated or inside the meter base as before. There are two hot legs plus a neutral that enter the meter base so if you're losing one of the hots that leaves you with only one hot or a "single phase" in lieu of a two phase.

Each hot leg is 110 volts so when you combine them together that's what gives you 220 volts. Each hot leg provides power to multiple 110 volt circuits via the bus bar so that is how you can see the effect in multiple places.

I had the cover off the breaker box and noticed an arc from behind the 200amp main breaker. I tightened the lugs on the breaker, and every screw in the box. After I turned the power back on, I saw a small arc from behind the main breaker when the heater came on. It's a Murray box and breaker, both around 30 years old. So does it sound like the trouble is in the breaker to you guys? And are breakers that old still available?
Thanks for all the help...

Any kind of arcing is bad and will eventually lead to the circuit breaker or a bus bar failure. Since you can't inspect the main breaker and bus bar without pulling the meter I'd suspect you failure is hiding behind there. If you caught the failure in time you could just be able to clean up the bars and replace the main breaker but you might be in for an expensive repair if the damage ha already been done. Service panel replacements range from $1,000-$2,000 depending on your case.

Yes, murray breakers are still readily avaliable at a reasonable price unlike the older Zinsco breakers which run over $1 an amp right now.

Thanks Andy!