Installing Ceiling Fans
Disconnect the power before you mount the box.
Turn off the power at the main service panel. Plug a lamp or circuit tester into the circuit you will be working on to confirm the power is off. Electric wires will need to be threaded through the fan's down rod and hooked up according to the manufacturer's instructions. When in doubt, consult an electrician.
Choose the best location.
Place your fan as close as possible to the middle of the room. Blade tips should be a minimum of 18 inches from any wall or cabinet. If there is a ceiling fixture where you plan to put your fan, you can probably use the existing wiring.
Use a metal electrical box approved for ceiling fans.
The electrical or junction box in the ceiling must be able to withstand the weight of the ceiling fan. Plastic boxes typically cannot handle the weight or the vibration of fans.
Be sure the power is off before you start your installation. Use heavy-duty electric parts designed for ceiling fans.