I recently purchased my house and I have a few questions.

  1. The breaker trips each time the vacuum is used. It looks like the previous owner has most of the house wired on to a 15 amp breaker (AC/ Furnace, living room, bathroom, and half the basement). Is that correct?

  2. Should I put any of those on a dedicated circuit?

I included a few pictures for reference. I tried to label as much as I could figure out but there are a few mystery breakers.

Thanks Updated with another picture enter image description here

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After looking at it more carefully:

  1. So it looks like the 30 amp breaker with the 14 gauge wire is to the garbage disposal.

  2. The AC is wired the a double pole 20 amp with 14 gauge wire.

  3. The two single pole 15 amp on the bottom right (red and black) are spliced together (wire nuts) to two wires coming from the same metal conduit.

  4. Ground and neutral wires are connected to the same bus bar in the same slot.

These things seem odd to me...

  • 2
    What's the single-pole 30A breaker for (left side, third from the bottom)? That seems unusual, and could be a case of somebody sticking a bigger breaker in to prevent the properly-sized one from tripping so often, which is a huge fire risk.
    – mmathis
    Oct 5, 2017 at 17:22
  • 2
    Good catch. Looks like #12 (or smaller) connected to it.
    – isherwood
    Oct 5, 2017 at 17:23
  • Its one of those mystery breakers that we dont know what it powers.
    – Dan
    Oct 5, 2017 at 17:44
  • Turn it off, and you'll find out right quick. Oct 5, 2017 at 19:41
  • 1
    @isherwood there's nothing weird about a white wire going to a 2-pole breaker in the cable wiring method. Since obviously neutral was not used, it must be a 240V-only load wired with /2. TODAY you're supposed to tag it with black tape, but before it was legal if the usage was "obvious", which it is. As for neatness, wires have one job, reaching breakers, and they need enough spare length to let you move them around. They fail if some panel fashionista has snipped them short for style points. Oct 5, 2017 at 19:51

2 Answers 2


There's really no substitute for painstakingly mapping your house, going to every outlet (by which I mean "point of use", including hardwired loads) and figuring out which breaker serves it. I have done this A LOT. It helps to own a bunch of dollar store nightlights, strings of Christmas lights, whatever you can plug into a receptacle. If I were king, it would be required to be marked on the outside or inside of every outlet.

If you're exceptionally clever, you can put a card with each breaker number on it, at each outlet. Turn off half the breakers, go through and if it has lost power, cross off the still-on breakers, and vice versa. Turn off a different half and repeat. Soon you narrow it down to 1 possibility.

After you've done the mapping, you can think about the likely route of the wires, and ways to access that wiring to add "home runs" back to the box. For instance if your wiring goes Panel-A-B-C-D-E-F-G-H-I-J-K-L, and you can route from point I to the panel, then you run two 12/2 cables there, feed I-L with one cable, E-H with the other cable, and in box D and E, disconnect the cable that interconnects them. So now your segments are Panel-A-B-C-D E-F-G-H-Panel Panel-I-J-K-L.

But this will only be the result of your particular mapping, and the logistics of pulling cable in your particular home. As such we cannot begin to advise you.

** Using the formal definition of "outlet", anyplace a load connects, including hardwired loads like lamps and fans.


You need to replace the 30 amp breaker mentioned in the comments with a 20 amp breaker. #12 wire is not allowed to be protected by a 30 amp breaker.

You have 4 spare slots that you could put breakers in and separate your loads. Also, if the wire going to the 15 amp breaker is #12 (yellow cable) then you can swap that breaker for a 20 amp.

Bathroom circuits are now required to be on their own circuit and any receptacles in them have to be GFCI protected.

Also, any receptacles in the unfinished part of a basement have to be GFCI protected.

Good luck and stay safe!

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