Electric fans suspended from the ceiling are a popular way to add comfort to any room. Unlike air conditioners, they do not change air temperature; instead, they circulate air. They only introduce movement to the air through their rotating paddles. Some fans reverse the direction of the blades to help in heating and cooling the air. They use much less power, but are nevertheless effective and efficient. The fresh breeze they provide can be a perfect substitute for more expensive, energy-consuming air conditioning units.
A ceiling fan is composed of an electric motor, blades or paddles, metal arms, a flywheel, a rotor, and other components. The paddles, usually three to six in number, connect to the motor by metal arms or blade irons. Paddles mount either under, on the side of, or on top of the electric motor. Depending on the style, fans may include downrods, metal pipes used to suspend the fan from the ceiling, a switch housing, and even lamps, up lights, or down lights.
Fans vary based on energy consumption and style:
- A cast-iron ceiling fan is solidly built, with a housing encasing a very heavy-duty oil-bath motor, which needs periodic oiling.
- A stack-motor ceiling fan, whose fan blades are mounted to a central hub called a “flywheel,” is an energy efficient motor far less costly to operate than air conditioning equipment.
- A direct-drive ceiling fan, which is the least expensive, uses a motor with a stationary inner core and a shell that revolves around it.
- A friction-drive ceiling fan, which consumes very low energy, employs a low-torque motor mounted transversely to the flywheel.
There are also different ways to operate ceiling fans. Some come with a pull-chain or pull-cord control. They are equipped with metal chains or cloth cords, which, when pulled, cycle the fan. Successive pulls either change the fan speed or turn the fan off. Other fans operate on a variable-speed control where a dial, which works like a dimmer switch, is mounted on the fan. Some fans have their controls mounted on the wall, while others come with wireless remote controls that transmit radio frequencies or infrared control signals to the receiver installed in the fan.
Since their first appearance in the early 1860s, ceiling fans have evolved into an important addition to our homes. They have served their purpose effectively—to circulate the air we breathe.