September 2007
How Energy Efficient is Your Home?
Take this quick do-it-yourself home energy audit quiz to see if your home's efficiency is up to par.
Choose the answer that most closely fits your home.
HEATING AND COOLING
Heating and cooling systems should be inspected twice a year - spring and fall - to ensure that they are functioning properly and safely. This will help with efficiency as well as life expectancy of the units.
The U.S. Department of Energy requires that all new heating and cooling units meet minimum efficiency standards. These standards are raised every few years, meaning that older units generally aren't up to par. For air conditioners that are rated by SEER, or seasonal energy efficiency ratio, the DOE requires at least 13 SEER. For gas furnaces rated by AFUE, or annual fuel utilization efficiency, the government requires an AFUE of at least 78 percent, but recommends an AFUE of at least 90 percent. If your unit is older than 10 years, you might want to look into replacing it with a more energy efficient model.
Most systems use filter covers and filters to minimize the accumulation of dust that can reduce system efficiency. Filters need to be changed monthly to ensure that air flows through them as needed to heat and cool your home. An air filter that is left in place too long or not covered will become plugged and will reduce air flow.
You can save as much as 10 percent a year on your heating and cooling bills by simply turning your thermostat back 10 to 15 percent for eight hours. You can do this automatically without sacrificing comfort by installing a programmable thermostat. If you have a dial (mercury) thermostat, be sure that it's level on the wall - an out of level thermostat can be off by four degrees.
*Mastic is a sticky paste reinforced with fiberglass made specifically for sealing duct work.
Ducts distribute heated or conditioned air thoughout your home. If your ducts aren't properly sealed, the air you are paying for will instead leak out and condition your attic, crawl space or basement. This can reduce your system's efficiency by 50 perecent. All the ductwork connections should be sealed with UL181 tape and mastic. If the duct leakage is 20 percent of the total air flow, the efficiency of the cooling system can drop by 50 percent.
Next page: Water Heating and Water Use
Page 1: Heating and Cooling
Page 2: Water Heating and Water Use
Page 3: Lighting
Page 4: Insulation
Page 5: Air Leaks
Page 6: How'd You Do?