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Electrical Wiring in the Home/Separating fan switch from light switch

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QUESTION: I live in Alberta, Canada. I have a bathroom which has the light switch on the hall wall outside the bathroom. Inside the bathroom, about 3 feet away is a GFCI and a fan switch. The only way the fan and the GFCI work is if the light is switched on.

I would like to be able to have the fan run independently of the light, and the GFCI run independently of the light. How do I wire the setup?

The light switch has 3 sets of wires coming into the box. All the whites are joined together. All the ground wires are grounded to the box. One black wire is attached to the top of the light switch. Iím not sure where the wire originates. A second black wire is attached to the bottom of the switch. This wire continues on to supply power to another room in the house. The third black wire is also attached to the bottom of the switch. This is the one that tests live when the switch is in the Ďoní position.

Inside the bathroom is a double box with the fan switch and the GFCI receptacle. There are 3 sets of wires coming into the box. Two of the grounds are grounded to the box. The third is attached to the GFCI green ground screw.

One black wire coming into the box is attached to the top of the fan switch. (Itís white wire is joined to other whites). (I assume it originates at the fan)
A second black wire coming into the box is attached to the bottom of the fan switch. This wire is live when the light switch is in the Ďoní position. (Itís white wire is joined to other whites) (I assume this one comes from the light switch outside)
A short black wire runs from the bottom of the fan switch to the top (line) brass screw on the GFCI. If this wire is disconnected from the fan switch, and the light switch is in the Ďoní position, the fan will operate if turned on, but the lights do not come on and the plug does not work. (There is a short white wire that goes from the top (line) silver screw on the GFCI to the bundle of white wires)
The third black wire coming into the box is connected to the bottom (load) brass screw on the GFCI. (Itís white wire is connected to the bottom (load) silver screw on the GFCI. (Iím assuming this wire originates at the light fixture).

Is it possible to somehow rearrange the wires or something so that the light switch does not have to be on in order to have the fan working and the GFCI working?

ANSWER: Hi.

The only way to do that is to run another wire from the switch in the hall to the switch and outlet in the bathroom. When the switch is off in the hall, no power is getting into the bathroom.

If you are willing to do that, I can tell you how to connect it.

---------- FOLLOW-UP ----------

QUESTION: Thanks Bob

I think I might be able to run a wire from the bathroom to the hallway.

Please let me know how to connect them all.

Thanks
Marc

Answer
OK, the existing wire from the light switch in the hall, you want to control the light only, so at the fan switch, connect the wire coming in to the wire going to the light.  This should be all the wires except the wire going to the fan.  Just use wire nuts and connect black to black and white to white.

At the hall switch, run the new wire.  The black will connect to the black wire coming in from the power. If you need to know which one it is, carefully use a tester with the switch off and see which wire coming in has power. Connect the white to the other whites and the ground to the other grounds.

The new black wire at the fan switch will connect to switch to fan, which you should have disconnected from the other wire, since it goes only to the light. This should also connect to the black wire on the GFCI.  The new white wire coming in should connect to the white fan wire and the white wire going to the GFCI.  All grounds and green wires connect together.  
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Bob Sponaugle

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Just about any home wiring question. (not appliance repair) I have done all kinds of home wiring for myself, including adding a new breaker box, etc. Please, questions from North America only. Please be specific with details.

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