Unlike air conditioners, ceiling fans don’t lower a room’s temperature or remove humidity from the air. But you can boost your comfort level—and save energy and money—by using ceiling fans and turning off the air conditioning when possible or by turning up the thermostat a few degrees and letting the fan do the rest.

Consumer Reports doesn't rate ceiling fans because in our past tests, most ceiling fans performed similarly on low and high speeds. But we did find some features that make a difference if you plan to buy a ceiling fan.

Ceiling fans come in a variety of styles and finishes. In the past, we tested a number of three-speed, 52-inch-diameter fans, the most popular size. We found that spending more didn’t guarantee better performance but did get you fancier finishes on the motor cover and blades. We also learned to predict how noisy a fan would be just by looking at its design. Here’s what else our tests revealed:

Fans save energy. The recommended indoor temperature for summer is 78° F, but some people set the thermostat much cooler. According to Energy Star, you can save 3 to 5 percent on air-conditioning costs for each degree you raise the thermostat. Using a ceiling fan, which costs little to run, can make you feel up to 4° F cooler. (Don't forget to turn off the fan when you leave the room—fans cool you, not the room.)

Airflow and blade shape matter. Look at cubic feet per minute (CFM) numbers on the box or on the manufacturer's or retailer's website to get an idea of how well the ceiling fan moves air. A higher number means more air movement, but don’t fret over small differences. Our tests showed comparable airspeed from fans rated from 5,000 to 5,600 CFM. Fans with the most airflow also made the most noise, but it was wind noise and fluttering, not motor noise. And be wary of fans with large blades that have ridges, bumps, or other surface texture; those often make more noise on high than fans with smooth blades.

Wobble can be fixed. Most fans come with balancing kits, a combination of weights that you attach to the blades to make up for slight differences in blade weight and removable clips that help you determine where to place the weights. You can eliminate most of the wobbling with such a kit.

Find the Right Ceiling Fan

Look for the Energy Star. Fans that earn the Energy Star label move air 20 percent more efficiently than standard models. Energy Star fans with light kits are 60 percent more efficient than conventional fans with light kits and can save you more than $15 per year on utility bills.

Select the right size. Though 52-inch fans are the most popular, that size—give or take a couple of inches—works best in rooms that are 225 to 400 square feet. Choose a 42- to 44-inch model for 144 to 225 square feet. Opt for a larger fan if your room size is on the borderline, and run it on a slower speed, which will be quieter.

Suit your style. From basic to ornate, ceiling fans can bring back memories of “Casablanca” or have a Jetsons-like modern twist. Motor-cover finishes include brass, bronze, and pewter. Basic fan blades have a paddle shape, but variations include oval and leaf shapes or wicker-like textures. Finishes include cherry, oak, maple, and painted blades.

Know installation requirements. Install a ceiling fan in the center of the room at least 7 feet above the floor, and 8 to 9 feet for optimal airflow. Generally, blade tips should be no closer than 24 inches from a wall and from drapes. Check manufacturer’s directions for specifics. If you’re replacing a light with a fan, be certain that the electric box in the ceiling can support the weight of the fan. Not sure? Check the installation instructions or call an electrician.

Check the wet/damp rating. If you’re placing a ceiling fan in a bathroom or outdoors, you need to find one that meets UL’s wet/damp rating. If the fan is indoors in a moist room, look for a UL damp rating. If the fan will be placed outdoors on a porch, look for one with a UL wet rating. Energy Star says that fans with these ratings have such features as sealed moisture-resistant motors, rust-resistant housing, stainless steel hardware, and all-weather blades.

All About Light Kits

Ceiling fan light kits come three different ways: integrated into the fan, included with the fan at the time of purchase, or sold separately. Many of the light kits that are sold separately are universal, meaning they can be used on a number of different fan models. Similarly, most ceiling fans are light kit adaptable. However, there are many cases where compatibility is only between light kits and ceiling fans under the same brand.

If your fan doesn't include lighting, buy an Energy Star certified light kit. This lighting is efficient and long lasting, so you won't have to make frequent bulb changes. There are three common types of light kits. Branched and stemmed light kits have cans or globes that can point up or down. Uplight kits sit on top of the housing and point toward the ceiling, casting a softer light.

Nearly all Energy Star certified ceiling fan light fixtures use bowl lighting, which can be attached either directly to the ceiling fan housing or below the fan. Bowl and shade designs range from clear to alabaster, crystal, or tiffany. Typically, the fancier the glass design, the more expensive.

Lightbulbs. Not all CFLs and LEDs are intended for use in ceiling fans. If your fan has bowl lighting, look for a lightbulb that can be used in an enclosed fixture. If your fan has cans or globes in which the bulb points down, you’ll need lightbulbs specifically intended for use in ceiling fans. Keep in mind that lighting affects energy use. LEDs are more efficient than CFLs, and CFLs are more efficient than halogen lightbulbs. Incandescents are the least efficient of all and are being phased out.

Match the Fan to the Room

The style you choose should add to the room décor, like a piece of furniture. You might want to install more than one fan in very large spaces, such as a great room, or if your home has an open floor plan.

Hang it high. A fan at 8 to 9 feet is best for optimal airflow, so if your ceiling is higher, use a downrod to position the fan at the proper height.

Connect with color. Coordinating the fan’s finish with other furnishings helps create unity and balance in a room. You can match the color of a wood fan blade to the floor. Metal fan finishes can coordinate with doorknobs, cabinet hardware, and even kitchen faucets and bathroom fixtures.

Blend it in. If you want to make a fan less obvious, choose a very simple style in a color that blends in with the ceiling. A flush-mounted fan will disappear into the ceiling a bit more.

Keep It Clean

Cleaning a ceiling fan.

Dirty fan blades don’t move air efficiently, so clean all household fans at least once each cooling season. A ceiling fan that's covered with dust or pollen might also fling the offending particles around the room as it's whirring away. And if you have a fan in the kitchen, cooking grease can make it a dust magnet. That’s why it’s important to keep the fan clean, especially if you use it year-round. Doing so requires a ladder, an all-purpose cleaner, and only a little effort.

Cover the floor and furniture. Spread a drop cloth or old sheets on the floor and over any furniture that's near or under the fan. Try to cover an area about twice as wide as the full width of the fan. Position the ladder so that you can see the top of the blades. Remove any globes and hand-wash them in the sink.

Dust, then wash.  Start by removing loose dust with a cloth or duster. Then moisten a cloth or sponge with an all-purpose cleaner—don’t spray liquid on the fan—and wash each blade. Don’t apply heavy pressure, which can bend the blades and cause the fan to not work properly. Dry thoroughly; damp blades attract dust.

Cool tools. You can clean both sides of the fan blades at once using a long-handled, U-shaped brush; this special tool is available from hardware stores and home centers. Don't have this tool? A few cleaning websites recommend slipping an old pillowcase over the blades one-by-one, then pulling it back to remove dust and dirt. If cleaning the ceiling fan is a chore you hate, try waxing the blades with car wax, which can prevent dust from sticking.