As the unofficial start of the summer season kicks off this holiday weekend, many parts of the country will begin to heat up, meaning now's the time for an air conditioning audit and getting your unit into shape before the scorching heat sets in.

Home Depot experts suggest conducting a 30-minute energy audit.

"The first step is to find out which parts of your home use the most energy," said Dave White, with the Home Depot. "It takes about half an hour to check your home's cooling system, insulation, ductwork, and other areas where you could be wasting energy. From there, a number of simple projects will help to reduce your energy usage and still keep cool during the hot summer months."

White suggests you do the following as part of your energy audit:

• Clean your cooling systems. Specifically, clean out the dust and debris. Replace or clean filters once a month and have a professional check it out once a year.

• Seal and insulate ductwork. If your ductwork leaks, it can cost you up to 30 percent of your heating and cooling costs each year -- that can mean hundreds of dollars. You should seal and insulate with mastic or other duct sealant, then wrap it with fiberglass or rigid foam insulation.

• Seal gaps in windows and doors. To test it out, close and lock the door or window sash on a dollar bill. Pull the bill out. If there isn't any resistance, repair or replace the weather-stripping along the tops, sides, and bottoms of the doors and windows.

• Use a programmable thermostat. Get a unit that comes preprogrammed with temperature cycles so your air conditioner will turn on and off automatically.

The U.S. Environmental Protection Agency, through the Energy Star program, also recommends summoning an energy auditor to evaluate your home's energy efficiency. Many gas and electric companies offer energy audits.

When you begin working with an energy specialist, the federal energy experts recommend you ask:

• How long the evaluation will take. A thorough evaluation can take up to three hours, but can vary depending on the size of the home.

• If they will provide a list of improvements.

• If they can make the improvements.

• If they can recommend someone who can make the improvements.

Finally, when it comes to your cooling equipment, Energy Star says there are telltale signs that indicate it's time to make a replacement. Those include:

• Your air conditioner is more than 10 years old. If you replace it with an Energy Star unit, it will use about 20 percent less energy than other models.

• You need frequent repairs and your energy bills are mounting.

• Some rooms in your house get too hot or too cold. You might be experiencing improper equipment operation, duct problems or inadequate insulation.

• Your house is humid. If the air is dry in winter or humid in summer, you may be experiencing poor equipment operation, inadequate equipment, or leaky ductwork.

• You have a lot of dust. Leaky ducts can attract particles and air from attics, crawl spaces and basements, distributing them throughout the house. Sealing your ducts may solve the problem.

• Your air conditioner is noisy. This could indicate an undersized duct system or a problem with the indoor coil of your cooling equipment.

Published: May 31, 2004

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