This is the wall in question, see my picture frame wainscoting there, I already pulled out the nails in question.



Close up picture of the sconces...anybody teach me how to take it off please??

 

Just from what I can see in the picture, it does not look like those were installed correctly to being with. Are they original to the house? I cant imagine an inspector would have passed it. It looks like the wire is just coming out of the wall and bunched up behind the sconce without a proper box behind it. If that is the case, you should still consider getting an electrician in to correct it. These types of fixtures must have a box behind them. Seeing this now, I am not surprised it shorted out with a little banging on the wall.

As for removing them, take the globe off, and there should be a little nut in the middle behind the light bulb that will unscrew or two smaller ones on each side of the light bulb to release it from the wall.

 

yes they are original to the house...inspector did not say anything about them. this is a 12-year-old house and we moved in about a year ago and never used this formal dining room.
now i'm just starting to make this room functional and got myself into trouble lol

so the nails were definitely not live/did not hit wires? So I should next focus on fixing the sconces then?

 

You still tripped the breaker, so all is not fine. Checking the wiring at the scones is a logical next step. And it does appear that they are not mounted to boxes.

 

Maybe the previous home owners installed these sconces themselves...

Another puzzle I have - so I put one end of the tester in the short slot of the extension cord and other end on the nail, it gave me 120V reading on 5 nails. No reading on other nails. Why is that? What does it mean?

 

what is a sconce box? I googled and seems like the box is inside the drywall?
so you guys are saying it does not look like there is a box in the drywall for the sconce?

Thank you guys for your patience, I have too many dumb questions..

 

It just means that the nails were grounded, which could have happened a few different ways, but not necessarily due to hitting a wire. If the nail was the cause of the short, there would almost certainly be a black mark on the end of it, which you say there wasent. You said you tested the nails after the breaker blew. Did you turn the breaker back on before the test?

If the house is only 12 years old, I am confident that all the wiring in the house would have passed inspection at that time. That being the case, there is no way these lights were there when the house was built. I agree that a homeowner added them at a later date. I say homeonwer becase an electrian would not install lights without a box. Now the question then becomes did the homeowner do it right and how did he run the wires for it. We know he didnt do the wiring at the fixtures right, so it is safe to assume that there could be other things in the walls not done right either. With this information, there could be a hundred reasons why your lights shorted out. You really do need to get an electrian in to take a look at it. I know it is not the answer you want to hear, but unless you have some basic wiring knowledge, and want to start pulling wires out, you will need a pro.

 

This is what should be behind your light, and it looks like it is not there.
[ATTACH=CONFIG]48611[/ATTACH]

 

Thank you Keith Weagle for the detailed explanation!

Yes I did turn the breaker back on before the test. No black ends. What a relief that I did not hit the wire!

It looked like the sconce is fixed to the wall using 2 screws, and there is a small hole behind the sconce with wires running through- so you are right, doesn't seem like there is a box.

I cant believe the home inspectors did not tell us! I will call a pro and tell him all these findings you guys helped me found.

In the mean time please do let me know if you have any suggestions for an easy fix! Definitely do not want to cut walls, won't mind loosing these 2 sconces since I don't use them anyways.

 

I wouldn't fault a home inspector for not noticing this, it is his job to make sure everything works, not to disconnect all the lights and verify they are wired correctly.

There is still an issue somewhere since you did trip the breaker. The only way you could have hit a wire with a nail that short is if the wire was laying over the stud and the drywall was placed over it, pinching it between the two. If that were the case, you should notice a hump in the wall there somewhere. Even then, it would be a one in a million shot for a nail that short to hit it just right to penetrate it and cause a short circuit. And it certainly would not have happened 4 more times.

If you want the lights, an electrician should be able to install a proper box for them, at the same time he can likely determine how it is all wired together and fix any other issues with it. If you don't want them, you will have to disconnect the circuit. Depending on how it is wired, it could mean losing other lights or outlets as well, but an electrician will be able to trace that out and rewire the switch so everything else continues to work. You will still have a couple small holes to fix behind the lights, or maybe just find something to hang over them.

 

I am now almost certain that the previous home owner did it, because i am aware that he did the basement (including wiring i think) himself, and just now I was trying to locate the breaker that controls the sconces and found out that it is the basement breaker!

so our dining room ceiling light is controlled by a breaker and the sconces are controlled by another breaker which at the same times controls all the basement lightings!! So they lived in this house 10 years and were just lucky enough all these faulty wiring did not cause a fire?

Could banging on the wall - loosening the wires behind the sconces tripped the breaker?

 

(Haven't followed the whole thread.) If you get ~120v between ground or neutral and the nail head you have a problem.

 

ray2047, it is between the short slot in the extension cord and the nail head. I guess the short slot is the "hot"?

So mean my nails are grounded some how...

 

The cord's short slot is hot. Testing a hot to ground should give you 120 volts. The ground is the nail in your test. Are these steel studs?

 

I can explain the BOOM, no problem there. There was a dead short somewhere probably with a loose connection to probably ground. When the switch was turned on the BOOM was the short clearing itself; it basically burned itself clear and now the breaker will reset just fine. If there was going to be a fire, that is when it would have happened.

Now, where was that problem? Was it a nail? Maybe, but it could have been a loose connection inside a wall box that came apart from all the hammering on the wall and touched a grounded surface. I think I'd pull each and every receptacle, switch and light out and inspect everything.

 

Thanks to all your guys who replied! I think I now have a clearer picture of what might have happened!

 

Since it now appears that the sconces were added to the wall at a later date....... it would be highly unlikely for the wiring to pass thru drilled studs from light to light. The wiring was done in one of three ways. Either fished over and thru the attic, fished under and thru the basement, or the sheetrock was notched across the face of the studs.

 

Hi everybody,

this is a follow-up to the original post. As some of you have pointed out, the wall sconces were not properly installed. Since there was not boxes behind the sconces, hammering on the wall made the wires became loose, and you can see the evidence below - the screw behind the sconce nicked the black wire and it touched the copper wire!
Now the problem has been solved by adding 2 work boxes behind the sconces. No need to open up walls or re-wire! such a relief!

 

Keith gets the +1 on this thread. Way back in March, and several times after that, he recommended you removing the fixtures. Something that apparently wasn't done until recently.

Thanks for letting us know what the problem was.