Content of the material
Optimal Sizing, Speed, and Placement
Use this formula to find the best fan size for a room’s occupied space (the part of the room where people gather the most): Occupied space (in square feet) divided by 4 equals the blade span (in inches). Step blade span down a bit for rooms with low ceilings, and go wider if the ceilings are high.
Another good rule of thumb is to remember that blade spans of less than 36 inches are ideal for spaces smaller than 75 square feet, such as baths and breakfast nooks. Spans of 36 to 42 inches work in rooms of up to 225 square feet, like a dining room. Larger living rooms and bedrooms can handle 50- to 54-inch blades.
Make sure that the cubic feet of air that the fan moves per minute (cfm), measured at high speed, is near the top of its class. Some 52-inch fans, for instance, rate as low as 2,050 cfm, while others reach 7,800. High-cfm fans not only provide a better breeze, they usually have robust motors that will last longer and run more quietly.
For optimal performance, the fan should be hung at least 1 1/2 feet from the wall or a sloped ceiling, 7- to 10-feet from the floor, and at least 8 inches from the ceiling. Steer clear of hanging the fan too close to any lights, as rotating blades under a bulb will create an annoying flicker.
Pull the wires out of the electrical box and unscrew the wire nuts, then pull apart the wires. Lower the ceiling fan. This may require the help of an assistant to hold the fan while you disconnect wires. Remove the mounting bracket, sometimes called a strap, that spans the electrical box.
Lift the light fixture’s base into position. Most light bases have curved, slotted holes into which the mounting screws fit. Tighten the mounting screws until the base is tight against the wall. Do not overtighten. The base should not be loose or be able to be turned easily by hand.
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