Ceiling fans are not all equal. The motor, the quality of the blades and elements like the housing are very important for their performance.
If you are going to buy a ceiling fan consider an Energy Star qualified unit. Energy Star ceiling fans are at least 50% more effective than common models.
If you are shopping for a ceiling fan, it's important to know the elements that make it effective.
Ceiling fans size and capacity
The fan-blade span is typically in the range of 29 to 54 inches (75 cm to 1,4 m).
52-inch fans are very popular, but the fan-blade span should be choosen according to the room's square footage.
The table above shows the Lighting Association and the Energy Star program recommendations. Also consider a UL-listed “For Use With Ceiling Fans” metal electrical outlet box (the box that houses the wiring).
A large and well designed motor determines much of the span and pitch of the blades, as well as the airflow and the capacity of the fan.
Ceiling fan motors are usually grouped into two categories: motors with sealed and lubricated ball bearings and motors with bearings that rotate in an oil bath. But this distinction is not really important. Motors with sealed bearings require less maintenance, but that’s just a relatively small detail.
The Energy Star program considers three types of motors:
- Performance grade (powerful motors, for continuous use and quieter operation);
- Medium grade fan motors (able to operate for 12 hours or less per day).
- Economy grade motors (for small rooms and needs).
It's an important distinction, even if somewhat blurred in practice.
The ceiling fan blades and their pitch and replacement
Pay special attention to the quality of the ceiling fan blades, namely their materials and their sealing; blades should be sealed and have a special coating, to prevent warping, peeling or scratches and tarnishing.
Most ceiling fans have 3, 4 or 5 blades, but it's largely an aesthetic issue. 4 and 5 blade ceiling fans may require a larger motor (more blades put additional drag on the motor), but good designs have that into account and the number of blades is of little practical value.
Even the pitch of the blades is not important by itself. It’s true that the higher the pitch the more air the fan will move. But a higher pitch will be nothing without a good and large enough motor.
Changing the blades
Changing the original blades for aesthetic or other reasons can deeply affect the performance of the fan. Quality blades are part of a wider whole, and are weighted and designed accordingly.
The motor housing
The housing – the box that encloses the fan motor – is an important detail. Housings made from heavier materials (die-cast metals) vibrate less, make less noise and will help prevent fan wobble.
Larger housings may also indicate larger and better motors, able to function with high pitched blades.
The lifespan, the quietness and the quality of a ceiling fan depend also on elements like high-quality windings and bearings, or shock-absorber components…
Ceiling fans should be securely fastened to a ceiling joist or a support bracket, and installed at the right distance from the ceiling, floor and walls. The blades should be at a distance of 8 inches (20 cm) or more from the ceiling, and at least at 18 inches (50 cm) from any wall. For maximum performance ceiling fans should also be positioned about 8 to 9 feet (2.4-2.7 m) from the floor.
The downrod length can be calculated through the following formula: ceiling height (in feet) minus 9'... In other words, a 12 foot/3.6 m ceiling need a 3 foot/90 cm downrod…
Blade holders should not be misaligned. You can use a fan balancing kit to balance the blades and to stop the wobble. Follow the manufacturer instructions.
Though not exactly difficult, installing a ceiling fan is not also a typical DIY task. If you don't feel comfortable with electrical wiring, hire a certified electrician.
For ceiling fans reviews, see: Ceiling Fans, Amazon.
Our Video on Ceiling Fans and Portable Fans: