- 1). Turn off all power to the circuit you'll be working on at the home's circuit breaker box. As an extra fail-safe measure, tape a note to the box indicating that it should not be touched while you are working on the circuit.
- 2). Use a wrench to remove the old light or fan from the bathroom ceiling by undoing the nuts at the center or side. Lower it out of the ceiling. As you lower the old light or fan, disconnect the wiring. In most cases the wires from the wall switch to the light/fan will be connected with wire nuts. Simply twist these to the left and pull off to disconnect the wires.
- 3). Wrap the wires from your new fan around the existing wires. Match the color coding of the wires. In most cases there will be a black wire and a white wire, which you can match to the existing wires. Wrap the bare ends of the fan's wires around the existing wires, then slide a wire nut over the wires. Twist the wire nut to the right to firmly connect the wires.
- 4). Turn power back on to the circuit when the wires are connected and test the bathroom fan by turning on the wall switch. Turn the power back off and complete the physical installation of the fan.
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