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Discussion Starter · #1 ·
This is my first time posting here, hopefully you all can help me. I am remodeling my bathroom and I need help with the wiring. I have an existing light over the sink with an existing single switch.... everything works fine...flip the switch the light over the sink comes on. I have added a fart fan in the ceiling, and I wanted a separate switch to control the power going to it. I have tried so many combinations of wiring it to get it to work but still have not succeeded. I have made a diagram showing what I have, if someone could maybe download it and draw out what I need to do and then re-upload it that would be the best. However, if that wont work for you, I completely understand. Maybe you could explain it out. Anyways, thanks for reading my post. :)

 

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retired framer
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The switches you want only have two screws.

In the switch box, the grounds are twisted together and attached to each switch as well as the screw in the back of the box. All three whites are nutted together.
The black from the wall or panel, nut it with two 6" pieces of black wire ( pig tail) join the pigtails to each to the switches. The black wires from the light and the fan one each to the switches.
At the light ground to ground and white to white and black to black, same at the fan.
 

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You can't do it. You do not have a neutral in the switch box. Your existing light is wired with a switch loop. Both wires are hot.
 

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Very Stable Genius
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Ya, if you only have 2 cables (with a black and white each) in the switch
box (1 cable from the light and the other from the fan) then @joed is correct.

If this is the case, one option would be to replace the 2 wire between the light
and switch with a 3 wire.
 

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Discussion Starter · #5 ·
Ok, so I have an update. It turns out that the two wires that are coming from the wall (black and white in the illustration above) Originally those two wires were connected to a switch and the switch controlled the sink light, yesterday I accidentally touched them with my hands and did not get shocked. LOL But they do turn the light on and off currently. I am suspecting that means that in an old 2 wire system that that was just a break in the (ground/neutral)? Anyone got any reason why I would not get shocked and that it still turns on the light?
 

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To get shocked you need to touch two different points. If you only only touched the hot and nothing else no shock.

Like was stated before, you have a switch loop. You can not connect the new fixture here without more wiring, as there is no neutral.
 

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To get shocked you need to touch two different points. If you only only touched the hot and nothing else no shock.

Like was stated before, you have a switch loop. You can not connect the new fixture here without more wiring, as there is no neutral.

um, what??? maybe if he was floating, or had electrician boots on, which I doubt..
 

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retired framer
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um, what??? maybe if he was floating, or had electrician boots on, which I doubt..
You might be hard pressed to find a grounded anything to stand on in a modern bathroom.:smile:
 

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Very Stable Genius
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um, what??? maybe if he was floating, or had electrician boots on, which I doubt..
I disagree completely. If you don't have good contact to something
grounded you won't get a jolt. Running shoes are more than enough
to give isolation from 120V.
 

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Discussion Starter · #10 ·
Alright, we just decided to find a power source in the basement...right under the bathroom and drill a hole and run it up to the switch box. However, after we went back today and checked out the switch one more time, I stuck my hand on the bolts on the switch (with the lights off) and lo and behold I got hit :vs_bulb:. LOL But when the switch is on it does not shock you when I touched it. After reading the posts I am leaning more toward what @joed said. Seems to me to be a loop running from the light and the switch is just a break in the loop. Obviously, I am no electrician, but I am sure that running a second switch off of what I have can not be done. Lesson learned. Thanks everyone.
 

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retired framer
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So that would be your light, you could just take power from the light to the fan and back for a second switch or use power from your new wire to run to the fan,
 

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An alternative- because we have needed to do this to add fans to bathrooms in the past where we had tenants who refused to open their windows and caused paint issues due to excessive humidity.. I digress.

This method works primarily if you have wires running in conduit and not romex-

A double switch (easier, less conduit box fill, no changing of plaster rings or maybe boxes) or two switches (second switch requires more to the box fill, often overfilling the box) can be used but it basically involves creating a larger additional switch loop.

-The power comes in at some point, most likely where the light is.
-A loop goes to the switch.
-You would then need to loop a feed to the fan as well to supply hot and neutral. The neutral would tie in with the neutral feeding the light which goes back to the supply, and the hot would loop to a single switch or double switch.
-If a double switch (2 switches on a single device) is used, the power goes to one side of the switch (often a black screw). The wire that runs to the light connects to the other side. Then a new wire runs from the second switch terminal to the light box and ties into the fan's power.
-If 2 single switches are used, it's the same setup as the double switch, only you need to pigtail a second wire off the hot, one to each individual switch. The only issue is that a lot of switch boxes are not sized for so many wires and a device as well, especially in older homes and running 3 wires to a single device is the easiest way, especially if they run to a handy box that only allows for a single device.
 
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