Playing it Cool: Beating summer's heat

By Karen McLaughlin

 AC units and fans help make our homes indoor havens from the heat and the humidity. In evaluating your home's summertime comfort, there are many factors to consider: the size and age of the house, its insulation and ventilation, your comfort needs, and your budget.

Air conditioners, both central air units that serve a whole house and window units that cool an area of the house, deal a double punch to summer woes by cooling the air and lowering humidity.

Central air conditioners distribute cooled air through the house's ducts. Air registers, or openings in the walls, floors, or ceilings, carry cooled air from the air conditioner to rooms throughout the house. AC units use a substantial amount of energy, but new developments have made them more efficient than ever and new ratings help you evaluate them more effectively.

Be a star

For maximum efficiency, look for air conditioning units that have earned the ENERGY STAR label.

ENERGY STAR is a joint program of the US Environmental Protection Agency (EPA) and the US Department of Energy. Its goal is to help consumers save money and protect the environment through efficient practices and products. According to the program, bigger doesn't necessarily mean more satisfactory performance in an AC unit. For maximum efficiency, look for units that have earned the ENERGY STAR label. ENERGY STAR-qualified products may also qualify you for tax credit: See www.energystar.gov for more information.

Choosing an installer

Installing or replacing a central air conditioner must be done by a licensed heating, ventilation, and air conditioning (HVAC) contractor. Pat Lupson, executive director of the National Capital Chapter of Air Conditioning Contractors of America (ACCA), recommends that you ask to see a copy of the contractor's license. “In Maryland , to be a ‘legitimate' contracting company, they must have a licensed member on staff,” she says. “All members of the ACCA have the necessary license to do work in the jurisdictions they work in.”

Lupson also adds that the company's technicians must be chlorofluorocarbon (CFC)-certified. CFC certification is a mandatory certification from the EPA to handle the refrigerant in air conditioners. You might also ask if the technicians are North American Technician Excellence, Inc. (NATE)- certified. “This is not a mandatory certification like the CFC certification,” she says, “but it is the leading certification program in the HVAC industry and tells the consumer that the company is concerned about the level of education their technicians have.”

Lupson also suggests that you seek a formal written work proposal and that when you compare contractors you check not only the price, but also that you are comparing the same services. Finally, you can ask for references and ask whether the contractor is a member of the ACCA. To confirm that a contractor is a member, call (301) 384-ACCA or (410) 431-8889 or check www.acca.org.

Thinking globally, cooling locally

Perhaps your home, like many in the Historic District, does not have central AC. Or you may be interested in additional cooling in a certain room or two. Room air conditioners, often installed in a window, may be just the right choice.

According to ENERGY STAR, size is also a consideration for room units. A unit that is too large can waste energy and still not do the best job. It will cool the room but only remove little of the humidity, leaving the room with a damp feel. Removing humidity is just as important as removing heat when it comes to increasing summertime comfort.

Cooling capacity is measured in British Thermal Units (BTUs). For the maximum efficiency, the ENERGY STAR program recommends an air conditioner that uses approximately 5000 BTUs for a 100- to 150-square-foot room, 6000 BTUs for a 150- to 250-square-foot room, and 7000 BTUs for larger rooms. Not fond of calculations? Check the BTU calculator at homedepot.com to get a BTU estimate.

However, the room's size isn't the only factor. A room that is heavily shaded by outdoor trees, overhangs, or even well insulated windows with substantial drapes can use 10 percent less energy, while a sunny room can use 10 percent more, to achieve the same cooling. If there are more than two people regularly in a room, think about bumping up the BTUs of each unit by 600 BTUs per person.

Also consider the power supply and type of plug the unit uses. For example, smaller units may be run on the typical 115-volt outlet. Larger ones may need their own circuits. Don't forget about the weight of a unit, as some units can weigh as much as 100 pounds. Noise is another consideration. Although newer models are quieter than older ones, when you are selecting a unit or choosing where to place it you might want to consider the noise it may generate.

Portable AC units are also available. Although they tend to cost a little more than a unit installed in a window, they could serve your cooling needs. These units usually roll on castors and can be plugged into an outlet. A dehumidifier could also be a smart choice for a humid home and possibly boost the performance of smaller, older, or less efficient window unit air conditioners.

Cooling while caring—and saving

The latest advances in home cooling technology are all about saving green, in both consumer dollars and the environment. Consider replacing a unit that is 15 years old or older with a newer, more efficient unit. With features such as variable fan speeds and zoning, new air conditioners use less energy to do a better job than ever before—all at a better price.

“Costs have come down on the higher-efficiency equipment,” says Glenn Hourahan, vice president of research and technology for the ACCA.

When shopping for a new unit, the ENERGY STAR Web site also recommends selecting the unit with the highest energy efficiency ratio (EER). The EER is the cooling capacity in BTUs divided by the watts. Look for EER ratings of eight to ten for greatest efficiency in Maryland 's hot summers. Some window AC units

feature digital temperature readouts, timers, and variable-speed fans designed to save energy.

The coolant R-22, otherwise known as Freon®, is one of the most common refrigerants in household cooling systems, especially older ones. But because R-22 has been found to be harmful to the earth's ozone layer, it will no longer be manufactured after 2010. New alternative refrigerants that are safer for the environment have been made. These include R-410A, the newest coolant in the industry, and Puron®, another refrigerant alternative, available in units made by Carrier.

Some AC manufacturers, such as Carrier, are offering other features, too, such as ultraviolet lamps installed near the indoor coil to kill mold, viruses, and bacteria in the air. Carrier's Infinity series features air conditioners and thermostats that can regulate humidity, air quality, and fan speed and even detect when the system's filter needs changing.

Thermostats: programmable can cut electricity costs

A programmable thermostat can also help cut energy costs. These thermostats allow you to ration the energy you use to adjust the temperature, depending on your lifestyle. For example, if no one is home during the day or when the family is on vacation, you can program your thermostat to cool to a slightly higher temperature, maybe at 5 to 6 degrees above your normal comfort level, to run the AC less. Many of these thermostats are on a 7-day cycle, so you can program a different setting for weekends, when the family is home. The daily cycle you set can also keep energy use low in the middle of the night when everyone is asleep.

One newer innovation in thermostats is zoning. Thermostats with this feature control dampers for different zones in your home. “Once the set temperature in an area has been satisfied, it shuts off cooling to that section to focus on other areas of the house,” says Hourahan. So if areas of your house stay cooler than others, say, due to the shade of trees in your yard, this feature might be for you.

Such a feature is also useful for limiting energy to use in areas that are being used. For example, during the day, you might recoup some energy savings by not cooling your bedroom as much as the other areas of the house in use. Zoning can also help you focus on cooling your bedroom at night, while other home areas stay a bit warmer. This is especially useful in larger homes.

Bayside breezes: ceiling fans

Ceiling fans can enhance your home's décor and boost its cooling system. A fan doesn't cool the air but moves it, making the house feel cooler. If the house is air conditioned, a fan can help spread the cooled air around. Statistics gathered by home improvement specialists state that fans can help you save up to 30 percent of your cooling costs, and ceiling fans without a light fixture use about as much energy as a 100-watt bulb.

In choosing a fan, consider the room's purpose and its dimensions, including the height of the ceiling. Also consider the room's electrical wiring and the lighting—will lighting be a part of the fan or not? An overhead light fixture can easily be replaced with a fan with or without a light. Although you control the speed of most fans by using a basic pull chain, many fans offer remote controls you can use to regulate fan speed and lighting levels. Some fans are even programmable. No wiring overhead? In that case, it is best to call an electrician.

Feeling the breeze: size and location

Fan size is another factor. A fan that is too small won't move the air efficiently. To compensate, many homeowners will try to constantly run the fan at top speed, shortening the life of the motor. A fan that is too large will detract from the beauty of a room and look awkward. Casablanca , a national fan manufacturer, suggests that a fan with a 32-inch blade span will fit a room up to 64 square feet, or an 8 x 8 foot room. Rooms up to 144 square feet will need a fan with a blade span of 42 to 44 inches. Rooms up to 225 square feet will benefit from a fan with a blade span of 50, 52, or 54 inches. A blade span of 56 inches is best for a room larger than 225 square feet.

If you aren't feeling the airflow with the fan on, it is probably mounted too high. Many homes have high ceilings, but fans need to be close enough to be beneficial, approximately 8 to 10 feet above the floor. Low-profile fans keep the blades as close to the ceiling as possible for rooms with low ceilings or very little overhead space. Casablanca recommends downrods, which suspend the fan farther from the ceiling, for fans in rooms with ceiling heights of 9 feet or more. In a room with a 9-foot ceiling use a 6-inch downrod, with a 10-foot ceiling a 12-inch downrod, and a 12-foot ceiling, a 24-inch downrod. Downrods up to 60 inches long are available for very high ceilings, such as 15 feet.

A fan of style: ceiling fan style possibilities

Ceiling fans come in many different styles and can blend with almost any décor. Let the room's style be your guide—the fan you want in your living room probably is of a different style than one in your child's bedroom. Fan blades come in a wide variety of finishes, including light and dark wood and white or other colors. Many blades have a different finish on each side, so you can change the finish by simply turning over the blades. The motor and metalwork of a fan can be simple or ornate and have finishes in pewter or nickel. Some designs are sleek and contemporary with angular lines and narrower blades. Others feature ornate details and wood grain, resembling antique furniture. Whatever your décor, there is a fan that will complement it.

Fanning out into new places

If you have a covered porch or sunroom, a ceiling fan can make the area more comfortable, especially on warm days. The motor of a fan used outside should be designed to handle some moisture. Some fan companies, such as Casablanca , offer fans that are Underwriters Laboratories (UL) listed for damp or wet conditions, making them safe choices for outdoor settings. It's also a good idea to make sure that the fan blades are made of materials that won't mildew or warp with humidity.

Cleaning is a breeze

Fan blades and components should be dusted or vacuumed regularly and the motor may need to be oiled occasionally, depending on the manufacturer. Some fan companies offer a lifetime warranty—read the manufacturer's conditions.

Keeping cool for summers to come

When using a window air conditioning unit, prolong its performance life by cleaning the filter every 2 weeks or as needed. Many filters can be washed in warm soapy water, but those that are very dirty may need to be replaced. To clean the unit, take it out of the window; remove the outside housing; and vacuum the interior to remove dirt, insects, and leaves. After covering the electrical parts with plastic, wipe the interior with a damp cloth. Clean and repair the windowsill if necessary and then reassemble if necessary. Reseal the area around the unit with new weather-stripping.

Consider having your AC systems, especially central ones, checked at the beginning of the season before summer really starts to sizzle. A serviceperson would clean the outside unit, check for coolant leaks, and inspect the filter and interior coil. A unit that is low on coolant, restricted in airflow, or not draining properly won't operate efficiently, costing you more to keep cool.

“Consumers should also consider getting a preventive maintenance agreement with their contractor,” says Hourahan. “This makes you a preferred customer. You might get coupons or discounts, and (in the middle of the season) when problems start happening, they might not happen to you.”

Karen McLaughlin is a freelance writer in Severn . She has a fan on her porch and is thankful for her house's central air conditioning.