2 hot wires coming into receptacle

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Alonzo

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I had a question and I was hoping you guys can help. I am installing a new ceiling fan. There is a receptacle directly below where I want to install the switch for the fan. I was going to pigtail into the receptacle. When I removed the receptacle, there were 2 wires coming in both 12-2. After seperating them to find out which was the hot wire coming in, I discovered both black wires coming into the box were hot. Can I still pigtail into one of these. If so how? The house was built in '97.
 

JoeD

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How did you determine there were two hots. If you used a digital meter one of them was probably a phantom voltage.
 

Alonzo

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Hey JoeD, Thanks for the quick reply.
I used a simple neon circuit tester. It marks 110V, 220V 227V. I touched one end to the ground wire and the other end to the black. Both Black wires marked 110V. I tried this on another receptacle and only got one hot coming in. Could this simple tester give me wrong reading? How could I find out which is the correct wire? Is there another tester that is more acurate?
 

kok328

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The only thing I can think of is that one hot was powering the top or bottom of the duplex receptical (with the bridge tab removed) and the other hot was powering the opposite (bottom or top) of the same receptical (odd setup up but, I've seen stranger things).
 

paul52446m

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i have seen this happen if they wanted the top hot all the time and the bottom is coming from a switch, so you can plug in a lamp and run it from a switch. paul
 
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serpentine5

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Question, you did remove the wires from the receptacle before testing for voltage right?
What Kok328 said about the bridge tab, did you understand that? On a new outlet, you have two screws on each side, two are silver and two are darker colored, and then you have a single one that is usually green. on the sides you have the sets of screws and in between the screws you have a metal tab called a bridge, i bridges a connection from one screw to the other on each set of screws. That way if you only have one wire coming in, you attach the black to one of the darker screws, the white to one of the silver screws, and the ground to the green. as long as the bridges are in place it doesnt matter what screw you attach to in the sets as long as you put a black on the barker set and the white to the silver set of screws. The outlets are separate of the other, and the bridge connects them so a single wire can power the two outlets.
What Paul said about the receptacle having a constant on and a switched plug all on the same receptacle is the most common reason you will have two hots in the same receptacle box.
Attached is a pic of a normal duplex outlet with the bridges intact. You would grab the tab with side cutters and break it out of place to separate the two plugs.

IMG00225.jpg
 

budro

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you guys probably got it right, but i have seen folks not familar with digital testers accidently push the "hold" button on their meters and get 120v on everything. i've had a few laughs with them when they call me and they believe every wire in their house is hot. that plug would pop a breaker if there were two hots coming in and the tab not broke. some yahoo might have wired it wrong too. if it was on the same circuit it would still work with the tab intact. he can find out by killing one circuit and seeing if it shut off the other hot wire. a tangled web we weave. i guess i'm way old school cause i never heard of a "neon" tester. is that one that just lights up with no numbers? thanks, budro
 

JoeD

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The plug would not pop the breaker if both hots were on the same side of the service.
 

Alonzo

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I did remove the wires from the receptacle first and tested all the wires. I tried attaching a pic of the tester that I used, hopefully I did it correctly. Also, there already is a receptacle on the other side of the room that has a constant on lower plug with the top plug controled by a switch. The bridge on this one has been removed. The one I am working on still has the bridge intact and all of the switches nearby control something else.

DSC01969.JPG

DSC01972.JPG
 

kok328

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I had a question and I was hoping you guys can help. I am installing a new ceiling fan. There is a receptacle directly below where I want to install the switch for the fan. I was going to pigtail into the receptacle. When I removed the receptacle, there were 2 wires coming in both 12-2. After seperating them to find out which was the hot wire coming in, I discovered both black wires coming into the box were hot. Can I still pigtail into one of these. If so how? The house was built in '97.
Well if that's the case, use one hot to power the outlet and the other hot to power the ceiling fan.
 

JoeD

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It sounds like yo might have two circuits cross connected. See if you can determine which two breakers turn off the two hots or are they both on the same circuit?
 

serpentine5

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when you flip the breaker for that outlet, both hots die? or one stays on? If it is a single breaker that controls both hots, I would not worry about the reasons there are two on an outlet that doesnt have the bridge removed. If it is two separate breakers controlling the two hots, then I would want to know why.
But as kok says, I would use one of the hots to power the switch, and you could put in two switches and run a 3 wire from the switches to the fan to separately switch the fan and light instead of needing to use the pull chains. You can also put in a dimmer made specifically for fans to control the fan speed from the wall too....
you have two black in the receptacle box and no others? and both of these are hot?
Test across both the hots, putting your tester on both hots at the same time, and post back of you get a reading or not. I am thinking they wired that one up for 220 for some reason... do you remember if both the blacks were on one side and both whites were on the other side? or was one black on one side and one black on the other?
 

jwin

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my light is off, outlet not working? I test my outlet and there are two hot wires in two holes. Any suggestings? I need to fix this problem soon. Thanks
 

Jeff Handy

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Post pictures of all the wires in the box.
And of the receptacle, and show which screws used to be attached.

You are not describing it very well, even though you are making a good effort.

Power often comes into a box, then runs on to somewhere else.

Did both these black wires come off of brass colored screws?

If one wire came from a silver screw, it is a neutral wire, even though black colored.
It should have white tape or paint on it, but that can come off over time.

Be aware that you can’t trust wire colors when using cables like that.

Black wires might be always hot, or only hot if switched from somewhere else.
And white wires might be neutrals, or could be hot or hot switched wires.
The white wires in that case should have black tape near the stripped end, to indicate they are hots, not neutrals.

And if Uncle Joe or Cousin Moe did some wiring, then a black wire might even be a neutral, and not taped or painted white.

If one black wire is a neutral, it might be attached to a different circuit, and it could be looking for a path back to the breaker box, and the ground wire would provide that, so it would light up the tester.
 
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afjes_2016

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Hey people this post is 7 to 10 years old.
 

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