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Ned Ramm
mystery electrical issue

My daughter has an old home in pittsburgh. the electrical panel is probably 40 years old or more. We had an electrician add a 220v breaker for her clothes drier and that was the only change.

She has various circuits in the house that go dead. I had a handyman check all the outlets and switches. he repaired a few but didn't really find anything. The issue he had was that the circuits were working when he was there, so it made it hard to troubleshoot.

i visited her when they were out and when i tested the output side of the breakers i found that several were dead (no voltage to common or ground. All were in the on position.

to my surprise, when i had her turn on the dryer, not only did it work but all the other circuits regained power. Even afte the dryer was turned off, they remained on. they have gone off several times since and again, all come on when the dryer is started. I should have taken a picture of the panel but didn't think to do it. I realize that might help solve this.

Re: mystery electrical issue

I'd start by replacing the faulty breakers. You have to experiment, one breaker at a time, to determine which ones are bad or questionable. Hopefully, this will eliminate your daughter's problems.

Re: mystery electrical issue

If the panel's 40 years old and your having that type of an issue it might be best to get the Electrician back and have him take a look. It may be just the breakers, while everything is working move the breaker switch and see if anything shuts off, usually when a breaker goes bad you lose that solid feeling when you go from off to on, it feels a little mushy or soft till it fails completely

Re: mystery electrical issue

You stated " i tested the output side of the breakers i found that several were dead (no voltage to common or ground. All were in the on position." this suggests that you may have a loose main leg connection, every other breaker would have no power. Not sure how the dryer is affecting it. Call an electrician , working on main connections is not a job for an amateur


Re: mystery electrical issue

All good answers Ned. Could also be the power companies problem with a bad connection outside the house.

I would start with them, since it's free. If it's OK call an electrician...this is not an easy problem.

And, be very careful in the main power panel there is enough energy in there to create a huge fireball.

Re: mystery electrical issue

When you find that some are dead, is it every other breaker? That would indicate the connection on one side of the main breaker. The power to the house must be removed to work on this so you need a licensed electrician in order to get the utility company to remove and restore power.

If this is the case, then turning on the drier is essentially jump starting the dead side because you are pulling 220v across that connection instead of the normal 110v. Once in use it will stay in use for awhile.

Also if you are using a digital VOM, they do not load the circuit so under some conditions, they can give you a false reading. Was the circuit working, that is was anything on it turned on and working or not working when you tested it? A digital VOM gives the most accurate readings when the circuit tested is under load (in use).

Re: mystery electrical issue

I hope that this issue will be resolved because I know this is very dangerous for all of us.

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