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Electrical Wiring in the Home/Wiring a bathroom fan/light/nightlight combo


I am a do-it-yourselfer without a lot of electrical experience. I have installed a new fan combo above my bathroom, but I'm not sure how to complete the wiring. Here's a link to the instructions and the wiring diagrams for the fan that I purchased.

The bathroom has a light above the vanity controlled by one switch and one outlet next to the bathroom sink. I removed the light fixture above the shower area that was controlled by a second switch. Then I removed the box for the light and have the wires loose in the attic. There are three wires, each of them have a black, white, and ground in them. One comes from the circuit breaker box, one comes from the light switch. There's one more and I'm not sure where it goes. I do not know exactly how to wire in the fan. I bought a 3 way switch, but I do not have the black/white/red/ground wire going from the attic down to the switch. I don't want to wire everything together and ruin the fan. I would appreciate any advice you can give. Thank you!

Hi John,

This looks confusing but it is really easy. You have 3 switched wires. On the light plug you have the main light and the night light. On the fan plug you just have the fan.

1st all the ground(bare/green) and neutral(white) wire just get tied through to a ground or neutral from the power supply wire.

2nd the hot(black) goes to one side of your switch/switches(single pole). This will power the switch. When you 'Close" or turn on the switch the power will go through the switch.

Finally depending on how you want the different parts of the fan to work you connect the other wire to the second side of the switch.

To control the 3 functions of your fan you will need 3 single pole switches. Attach the black,Blue and red wire from the fan to the second screw of the 3 switches. You can also attach two wire to one switch but that will make two part of the fan work at the same time.  

You can also just not use one of the fans feature by not attaching one of the wires. Like the one on the night light.  
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Electrical Wiring in the Home

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Bill Lutz


Any questions about being an electrician or doing electrical work. I can help advise people on their wiring needs, what kind of outlets and switcher to use, explain what an electrical service is and how their breakers work. I can also help them with their lighting needs. . I CAN HELP YOU UNDERSTAND WHAT YOUR LOOKING AT.


My Father apprenticed to his Father-and I apprenticed to mine, repeating an invaluable tradition of child labor and a great place to learn a trade. Beginning at the age of 13, I worked with my dad every weekend and summer vacation in homes throughout Philadelphia repairing and rewiring all levels of residential electrical systems. Studying electrical engineering and earning a degree in architecture has given me a solid advantage in solving the myriad of residential electrical problems. Generation 3 Electrical, Inc. takes pride in every job - building confidence by how we do things - by being prompt, thorough and leaving every job site finished and clean.

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