Chilly temperatures prompt thoughts of staying warm — and maybe replacing that old furnace.
• If you're furnace shopping, look for energy efficiency. The more efficient the furnace, the lower your energy bills.
Furnaces with the Energy Star label have a rating of at least 90 AFUE or higher. AFUE stands for annual fuel utilization efficiency; a 90 AFUE rating means that the furnace is 90 percent efficient. In other words, the furnace produces 90 units of heat output for every 100 units consumed.
• To help your furnace work at its highest efficiency, change the air filters. Clogged filters slow the flow of air and make the furnace work harder. During winter, change the filters every month.
Here are more tips from energy expert Noah Horowitz of the Natural Resources Defense Council:
• Use a programmable thermostat. These devices let you reduce the temperature when no one is home and dial back up before you return. It's an investment upfront — about $100 for most homes — but this simple tool can carry much of the energy-efficiency load in your home, cutting heating and cooling costs by 20 to 30 percent, Horowitz said.
• Regulate humidity. The more humidity in a room, the warmer it feels, Horowitz said. A room temperature of 70 degrees combined with humidity of 10 percent feels only like 64 degrees, but 80 percent humidity makes it feel like 71. Use a humidifier to fight dry air. You'll use less heat and still feel warm.
• But don't turn your home into the tropics, Horowitz warned. Dust mites, mold and mildew thrive in high humidity. Keep the range between 30 and 40 percent. Follow the humidifier's cleaning instructions to deter mold and bacteria growth.