Furnaces heat the air and move that heated air through a series of ducts to different parts of the house. There is an efficiency rating on central furnaces with the AFUE label. AFUE stands for annual fuel utilization efficiency. This number compares the total energy that is consumed by the furnace. For example a 80 percent AFUE rating means that 20 percent of the energy escapes while 80 percent of it becomes household heat. Obviously, the higher the AFUE rating the better the furnace is on keeping energy costs down by reducing wasted energy.
Comparing Efficiency
When you start buying a furnace, compare the efficiency, or the AFUE. Most old heating systems are low-efficiency units, meaning that they have an AFUE rating between 68 percent and 72 percent. Newer models are mostly mid-efficiency units that have an AFUE rating between 80 percent and 83 percent. The newest high-efficiency units have AFUE ratings between 90 and 97 percent. Upgrading to a new high-efficiency unit from an older low-efficiency unit can give you up to 29 percent higher AFUE, which means that nearly 30 percent more heated air can get to the people that need it instead of it being wasted energy costs.
Size Matters
Perhaps you’ve added onto your home, or perhaps your home’s furnace wasn’t enough for the square footage of the home to begin with. When the unit is having to work harder to heat and cool your home, its life expectancy goes down. Have a qualified HVAC contractor size one for your home. Buying a furnace that is enough for your home can also decrease energy waste and decrease fuel costs. Properly sized units are better for quality efficiency.
So if you are looking to buy a furnace, check out the key factors above. Only you can decide whether it is more cost effective to spend more now to save in the long run, or save money upfront and pay more for your heating and cooling down the road.