Standard outlet to GFI

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Old 11-02-16, 01:34 PM
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Wink Standard outlet to GFI

I have a standard outlet that has two white wires and one black wire coming into it. I want to add a GFI outlet on the other side of the wall. I'm not sure how to wire it correctly.
 
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Old 11-02-16, 01:40 PM
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Is it a split switched outlet? In other words is half of the outlet controlled by a wall switch?
 
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Old 11-02-16, 01:49 PM
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Is it controlled by a switch? Sure there aren't some hidden wires in the box? An odd number of wires is not really possible in a working circuit.
 
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Old 11-03-16, 04:55 AM
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How (where) are the existing wires attached to the receptacle unit?

Normally, converting a regular receptacle to ground fault circuit interrupter (leaving the second set of terminals called the "load" terminals empty) is a no-brainer. But there are some caveats:

If half of the original receptacle is switched, then the final result will be wholly switched or wholly unswitched, your choice.

The GFCI receptacle unit might be too large to fit in the box together with all of the existing wires. This is due to physical size; the "legal" requirement called "box fill" will not be upset.

If the supply circuit hot and neutral already have GFCI protection then it is unnecessary and undesirable to put a GFCI receptacle here as to create redundant daisy chained GFCI protection.

Provided that the neutral is not shared with another hot wire just passing through the box (multiwire branch circuit), the new GFCI unit you are installing can optionally protect additional receptacles down the line.
 

Last edited by AllanJ; 11-03-16 at 05:38 AM.
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Old 11-03-16, 08:34 AM
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Red wires

There are red wires coming into the box but they are not attached to the outlet. Only the two white wires, a black wire and a ground wire. The outlet can't be switched if it isn't connected.
 
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Old 11-03-16, 08:46 AM
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Is it possible that the white wire on the lower receptacle connects to other outlets? That's what I am thinking. If so, where do i connect the GFI wiring? Do I pig tail to the white wire opposite the black wire, or to the other white wire?
 
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Old 11-03-16, 08:50 AM
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The white wires are connected to the upper and lower receptacle. The upper has both black and white wire on opposite sides, the lower only has a white wire, no black wire connected opposite. Do I connect the white wire from the GFI to the upper white wire, the one opposite the black, or to the lower?
Thanks
 
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Old 11-03-16, 08:53 AM
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Also note, the GFI is not going into the same box as the other outlet.
 
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Old 11-03-16, 03:09 PM
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Connect the wire for extending to the GFCI outlet to the black and white wire that are coming from the same cable to the existing outlet. Do you have a multimeter to check the wires for a constant hot to neutral? In other words power between the black and a white.
 

Last edited by ray2047; 11-03-16 at 05:37 PM. Reason: millimeter>multimeter
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Old 11-03-16, 06:25 PM
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The new GFCI receptacle on the other side of the wall will have a short cable going into the older existing box you are working on.

Remove both white wires from the existing receptacle. Cut a short length (pigtail) of white wire. Wire nut together these three and also the white wire of the new cable from the GFCI receptacle, total of four ends. Connect the other end of the pigtail to one of the silver screws of the old receptacle you unhooked.

Remove the black wire from the existing receptacle. Cut a black pigtail and wire nut it and the old black wire just unhooked and the new black wire coming from the GFCI, total of three ends. Connect the other end of the pigtail to the receptacle gold screw you unhooked the black wire from.

Repeat for the ground wires, using the green screw on the mounting strip of the existing receptacle.

There really should be another black wire in the existing box. You cannot have two white wires and just one black wire. The other black wire might not be needed for anything now but do not snip it off. Put tape on the end if not already and curl it up inside the box.
 

Last edited by AllanJ; 11-03-16 at 06:42 PM.
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Old 11-03-16, 07:35 PM
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Honestly, there are two white wires going to the outlet, but only one black wire.
 
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Old 11-03-16, 08:00 PM
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there are two white wires going to the outlet, but only one black wire.
Is this conduit or cable? Is this an apartment or condo?
 
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Old 11-03-16, 08:01 PM
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So I took off the second white wire and that seems to have had no effect anywhere in the house. Go figure, I have no idea.
 
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Old 11-03-16, 08:06 PM
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You posted as I was posting. Please answer my post above.
 
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Old 11-03-16, 08:58 PM
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Two white cables coming in, each with red, white black and copper. The red cables are pig tailed together. The white cables are as described. The black cables are pigtailed together with a single black wire going to the outlet. It is a home, not an apartment
 
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Old 11-03-16, 09:02 PM
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Let me try that again...
Two white conduits (Romex?) coming in, each with red, white black and copper wires. The red wires are pig tailed together. The white wires are as described. The black wires are pigtailed together with a single black wire going to the outlet. It is a home, not an apartment
 
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Old 11-03-16, 09:25 PM
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Two white conduits (Romex?)
No, Romex is cable.
The red cables are pig tailed together.
No, those are wires.
red, white black and copper wires. The red wires are pig tailed together. The white wires are as described. The black wires are pigtailed together with a single black wire going to the outlet.
Just for future reference this is how you should have described it in your first post. It is important when helping you we have a complete description.

Based on your complete description power comes from a switch on one of the 3-conductir cables (red, black, white) and leaves on the second 3-conductor cable. The red wire is your switch controlled power and the black is your always on power. Since apparently the receptacle is not switched the red was not used but both whites should have been pigtailed to it just like both blacks were pigtailed to it.

The fact only one white was used raises the question why? Do you have a receptacle that doesn't work somewhere on the circuit?

The whites from the new cable, and old cables should be connected to a white pigtail and the blacks from all three cables connected to a black pigtail. White pigtail to the silver screw of the old receptacle and black to the brass screw of the old receptacle. However first it would be best to determine why one white wasn't connected. Was it back stabbed and came out when you pulled the receptacle out?
 
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Old 11-03-16, 11:39 PM
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Okay, I think I have it. Both white wires were connected to the receptacle. I detached the lower one. The receptacle works. I can't find anywhere in the house where power is off after detaching the other white wire. Its an old house that was rewired in 1987. Maybe they were going to attach another receptacle somewhere but never did. I tried pig tailing to the black and connecting the white wire from the new GFI to the lower screw on the first receptacle. That seems to be working fine. If I ever discover an outlet that doesn't work I'll know why. Thanks.
 
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Old 11-03-16, 11:49 PM
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You got it working that was what is important. The other important thing is that the GFCI receptacle is not in a bathroom or kitchen. If it is that is not code compliant.

Do you have a ceiling light in the room? If you don't national code requires a receptacle controlled by a switch. If no ceiling light do you have a switched receptacle.
 
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Old 11-04-16, 04:30 PM
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Oops. you have a ticking time bomb.

You may not leave one of the two original whites from the back of the box detached and curled up while the two original blacks from the back of the box are connected together (and the two reds from the back of the box still connected together).

When you find something not working tomorrow, it might all be hot, white wire and all, because the overall neutral path going through today's work zone does not continue to that non-working receptacle or what-have-you. And that detached white could be hot today if there was something plugged in and switched on (but not working) downstream of today's work zone.

Good wiring practice today does not have the two whites relying on the two silver screws of the receptacle to hold them connected (and come apart if you work on the receptacle) while the two blacks remain solidly connected with a wire nut at the back of the box. Take the time now to rejoin all the whites with a wire nut and add a white pigtail to one receptacle silver screw.
 
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