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We redid our bathrooms and had an electrician come in and put in new wiring for outlets, heater/fan/lights and heated floors. He had to replace the electrical panel, because the house is older (1956) and didn't have enough space to accomplish the task. So he installed a new electrical panel. Everything was fine for a while.

Then the lights started to flicker and electronic devices started to pop on and off.

Then 1/2 the house started to lose power. No breakers were tripped.

We called the electrician and he said the power loss was probably coming from the pole and to call in the power company to check the line.

Power company came out, checked the line and determined it's something in my house that's causing the outage.

Since then the power has gone out for up to 24 hours at a time. Flickering lights signal the outage. Now being an old house they have most of the lights along one line. Dining room light, kitchen fan light and several outlets in our bedroom are on the same line (it's a ranch) on one side of the house, the other side has multiple fixtures and outlets as well. I went down to the electrical panel (surprise nothing labeled) to see which circuit breaker was causing the problem. Went up and down both sides of the panel, but not once did the lights or outlets go out. Finally I turned off one side of the panel (left) and then started to turn on breakers one at a time and discovered 2 separate breakers 6 down from each other combined, turn off the power to the lights and outlets along this line.

Now with the old box, no problems, electric did not flicker, nor did only 1/2 the house lose power.

Question, what did the electrician do and is it safe to be on 2 breakers like that until he can come out and look at the problem?

Thanks

  • So to turn off the lights, you have to turn off both breakers? If either is on, then the lights are on? Are you comfortable taking the cover off the panel? The lights/receptacles that are affected, do they include the ones in the new bathroom? – Tester101 Apr 22 '16 at 13:40
  • Shared neutral? – rpmerf Apr 22 '16 at 17:11
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    Sounds like a staple through 2 hots, or some hots accidentally wired together. A staple that broke 1 hot and connected a 2nd could cause this and if this is the case it is a real fire danger. This is the reason the NEC is requiring arc fault protection on new construction. Is your original wiring cloth wrapped? moving the wires around could have also caused the old insulation to break down coming through a plate or stud if pulled together. – Ed Beal Apr 22 '16 at 18:42
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    It could also be a loop circuit. That's a thing in the UK. The hot/neutral might go out of the box, go to several locations and come back to the box. The electrician thought it was 2 circuits (didn't really check) and just punched it down to 2 breakers. He's lucky he put them an even number of rows apart. – Harper Apr 23 '16 at 4:06
  • Unless your panel is a Pushmatic or other obscure make, turning off one side of a panel (left side) has nothing to do with which pole you are de-energizing. My answer on "spaces in the panel" talks about this. – Harper Nov 3 '17 at 18:38
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Did the electrician replaced the Service panel only, or (s)he also worked on other things like adding junction boxes and ran new conduits? The problem of 2 breakers (let's call #1 and #7 connected to the same circuit (lights in this case) might not be at the Service panel, but it could be that he had mistakenly connected wire from #7 to the existing light circuit which already had been connected to #1 prior to this, at the new junction box. You need to trace down where the old lighting circuit connected to those #1 and #7 wires.

  • Thanks for all your replies. As you can imagine, power was out most of the day yesterday and wasn't able to post. Took suggestions and turned off one of the breakers (20 amp one other is 15). Will try to remove cover today and see what is connected to what. – JDale Apr 24 '16 at 10:58
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There is no valid way for two breakers to control the same circuit. Either through accident (as suggested above, poorly placed staple) or oversight (creating a direct splice between hot wires belonging to two different circuits), there is a short between the output of breaker#1 and breaker#7.

This is bad, because, even if it was done through oversight and insulation was not punctured, two breakers combined likely have a higher current rating than wiring in each circuit. For example, if each breaker is 15A, it would trip if you try to draw 15A from its circuit, before overloading the wire. If you have two 15A breakers in parallel, that effectively becomes a 30A breaker, which won't trip easily and overloading the circuit would result in melted wiring inside the wall (you can imagine the outcome).

To protect yourself until the issue is properly dealt with, I would suggest to keep one of the pair of breakers permanently "off".

The fact that your lights go out at random without any breakers tripped suggests that there's a loose wire somewhere in the circuit that feeds those lights. This may or may not be related to the problem of parallel breakers.

Does the set of lights and outlets which go out random match exactly with the set of lights and outlets which are controlled by two parallel breakers?

  • Well, 2x15A is very likely no more than 15.somethingA because the breakers themselves probably have significantly different inner resistance (both very close to zero, so the ratio can be high). However, it's still not safe, since it's possible that they give 30A which the wires can't handle. – yo' Apr 27 '16 at 23:53
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Permitted? Inspected?

Usually a panel replacement would involve bringing the entire structure up to present-day code. For a remodel, reusing 1956 wiring would not pass inspection.

From the dialogue there are a couple notations:

  1. Too many devices on a single circuit.
  2. Sounds like existing wiring was reused. May be ok maybe not.
  3. There is an arc fault somewhere.
  4. There is a miswire or short between two breakers.
  5. Possible neutral issue at the pole or new panel.
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    Why? I'd argue this is not a remodel, just a panel replacement. You can't require whole house rewire for any panel replacement, or no one would replace a panel, ever. I know he's doing other work, but perhaps it doesn't cross the "remodel" threshold, or perhaps he "structured" (financial term) the timing of the work to evade the threshold. – Harper Apr 26 '16 at 21:21

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