How to Wire a Bathroom Exhaust Fan

Does your existing bathroom exhaust sound like a rumbling jet engine? Does it do a poor job of getting rid of the steam during a shower? If so, then you probably need a new bathroom exhaust fan. If you want to do the job yourself but have some reservations about wiring it, don't worry. Here is how to wire a bathroom exhaust fan.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Screwdrivers
• Wire strippers
• Wire connectors
• Electrical tape
• Flashlight
• Romex connector
• Romex stripper

1. Turn off the switch that controls your existing bathroom exhaust fan or, better yet, turn the breaker that controls the circuit off.

2. Look on the exhaust fan housing for the junction box. Remove the junction box cover. Inside, you will see the wires that connect to the light (if the fan has one) and the outlet that the fan motor plugs into.

3. On the side of the junction box, you will see a knockout. Use a pair of pliers to remove it. Take a Romex (NM cable) connector and remove the lock-nut. Insert the Romex connector through the knockout hole so the threads are inside the box. Then, secure the connector in place by tightening the lock-nut into position over the threads.

4. Loosen the 2 clamp screws on the Romex connector. Use the Romex stripper to strip about 6 inches of sheath from the NM cable being used to deliver power to the exhaust fan.

5. Use the wire strippers to remove about 3/4 of an inch of insulation from the ends of each wire. Then, fish the Romex wire through the connector and tighten the clamp down over the sheathed part of the wire (not the exposed insulated area).

6. Connect the ground wire from the feed line to the green grounding screw inside the junction box. If there isn't one included, use a wire connector to connect it to the other ground wire inside the box.

7. Use wire connectors to connect the black wire from the feed to the black wire to the exhaust fan. Then, do the same thing with the white wires. Wrap each wire connector with electrical tape (where the connector meets the wires) to help prevent an accidental short.

8. Tuck all of the wires back into the junction box and install the cover plate.

9. Follow the mounting instructions that came with your bathroom exhaust fan to secure it inside your ceiling.

10. Plug the exhaust fan into the receptacle located on the inside of the housing. Install the properly rated light bulb (if applicable) and cover.

11. Turn the breaker back on and test your new bathroom exhaust fan. It should be humming away!

Tips & Warnings

• Use a drop cloth to catch all of the debris that will be falling from your ceiling during the installation. Always wear eye protection whenever working overhead. Because you will be working in and around ceiling insulation, be sure to wear a face mask and other types of protective clothing.
• Don't forget to connect your bathroom exhaust fan to the exhaust line in your ceiling, or the steamy air will be pushed into your attic, causing potential mold problems.