How to Connect a Bathroom Vent

Take the bathroom vent fan's motor housing up to the attic. Slide a 90-degree elbow over the motor housing's port. Wrap foil tape around the seam where the elbow meets the port to hold it in place.

Locate the knockout hole on the motor housing's other side. Hold the tip of a screwdriver over the knockout hole. Hit the screwdriver's handle with a hammer to remove the knockout. Insert a cable connector into the hole.

Center the motor housing over the opening that leads to the bathroom. Insert it over the opening, between the joists. Pull out the side arms until the tabs rest on the joists located on either side of the motor housing.

Drive a 1 1/2-inch screw through the tabs' screw holes and into the ceiling joists. Fit the flexible ventilation duct, located in your attic and leading toward the outdoors, over the 90-degree elbow. Tape the two pieces together with foil tape. Check that the electrical cable coming from the vent fan's power supply has no power running to it, using a circuit tester. Insert the cable through the cable connector. Tighten the cable connector's screw to hold the cable in place.

Return to the bathroom. Look inside the motor housing and locate the screws that hold the motor in place. Back out the screws and lower the motor. Back out the screws securing the receptacle housing to the motor housing. Remove the receptacle housing to expose the screws.

Check that each wire has 1/2 inch of its rubber coating stripped off its end. Use wire strippers to remove the rubber coating if necessary. Hold the two black wires' ends together and twist a wire nut over them. Hold the two white wires' ends together and twist a wire nut over them. If your fan has a light, there will be three black and three white wires. Loosen the green grounding screw on the side of the motor housing. Bend the green or bare copper wire into a hook and wrap it around the grounding screw, then tighten the screw.

Cover the wiring connections with the receptacle housing you removed in Step 5. Secure it in place with screws. Insert the motor back into the motor housing. Plug the motor's electrical plug into the motor housing's outlet and secure the motor back in place with screws.

Lift a vent grille over the opening. Some vent grilles get secured to the motor housing with screws, while others have wire hooks on either side that hook into tabs inside the motor housing.