Georgia's weather is finally reaching the point that many homeowners are either piling on an extra blanket, turning up the thermostat or building roaring fires in the fireplaces.

After all, no one wants to be cold on a winter night -- that is, until the energy bills begin to rise. University of Georgia experts say lowering your winter energy bill can be as easy as replacing an air filter.

"Just like your automobile, your heating system needs monthly maintenance to perform properly," said Lisa Ann Kelley, a pollution prevention specialist with the UGA College of Agricultural and Environmental Sciences. Kelley coordinates the Home*A*Syst program in Georgia.

"Your heating and cooling system is the single greatest energy consumer in your home," Kelley said. "But you can reduce the cost of running the system."

Home*A*Syst is a national program that helps homeowners identify pollution problems and ways to correct them.

Most heating systems have three parts: (1) the heating unit, (2) the duct or distribution system and (3) the thermostat. Homeowners can save on their heating energy bills by inspecting each of these parts.

Kelley said Home*A*Syst offers tips on reducing home energy costs.

"If your heating unit is 15 to 25 years old or more, it's probably not very energy-efficient," Kelley said. "Even if it still works well, you could greatly benefit by replacing it with a new, energy-efficient model."

If the price of a new system turns you off, Kelley said the energy savings should pay for the unit in only a few years.

"If you finance your new unit, the monthly energy savings may exceed the monthly payment," she said.

All machines work more efficiently and safely if you regularly inspect and maintain them. "Forced-air systems include air filters you should change or clean regularly," she said.

Filters remove dust and debris before they reach the air blower and heat-exchange coils. Dirt on heating coils reduces the system's efficiency.

Kelley said your thermostat can be an energy-saving tool, too.

"One of the easiest ways to save energy is to set your thermostat at a lower temperature in winter so the system runs less often," she said. "When the system is constantly cutting on and off, it's wasting energy."

For the winter, Kelley recommends a setting of 68 degrees during the day and 50 to 60 degrees at night and when no one's home.

Another way to use your thermostat to your advantage is to replace it. "If your thermostat is an older model -- one you set to maintain a constant temperature -- it should be replaced," Kelley said.

The best thermostat is one designed to adjust temperatures depending on the time. "You can set these digital or clock thermostats to lower the temperature when you're at work and raise it just before you arrive home," she said. Or set it to turn the heat down every night at 11 and bring it back up by 6 a.m.

Finally, check out your duct or distribution system. More than 90 percent of U.S. home heating systems are forced-air systems. These systems use air ducts to move warm air around the house.

"If a duct system leaks, it can waste a lot of energy," Kelley said. "Inspect your duct systems and make any necessary repairs." If you find leaks, especially where air enters rooms, repair them with caulking.

Your heating system is probably not the only energy-wasting machine in your home.

"The best way to know your home's energy efficiency is to schedule a home energy audit," Kelley said. "Contact your utility company to see if they offer a home energy audit or can provide energy-saving information for houses like yours."

To assess your own home energy efficiency, contact Kelley at (706) 542-3086 for a Home*A*Syst self-assessment form.