What is an Energy Efficient Furnace?

It seems like everything around is labeled these days with things like organic, Non GMO, Sulfate free, and energy efficient. The thing is, though we know all of these things are good, what do they really mean and how can we truly know if the product meets these standards? Most of us would agree that an energy efficient furnace is better than a non energy efficient furnace, right?  But what is considered an energy efficient furnace, and how much of a difference does one make?  At FLAME, we can’t help you with labels about GMO and sulfates, but we can help you with furnaces.

A furnace’s efficiency level is measured with the AFUE rating.  AFUE stands for Annual Fuel Utilization Efficiency and the number is given as a percentage.  Basically the AFUE is the percentage of how much of the furnace’s energy is actually going toward heating your home. For example, a furnace with an AFUE of 80% will have 80% of its energy used on heating your home and the other 20% is wasted.  So you can see why it is beneficial to have furnaces with higher AFUE ratings- they save you money!

It is important to note that the AFUE does not include any energy that can be wasted though the pipes or duct system.  According to the EPA:

AFUE doesn’t include the heat losses of the duct system or piping, which can be as much as 35% of the energy for output of the furnace when ducts are located in the attic, garage, or other partially conditioned or unconditioned space.

So, in order to conserve the most energy in your home it is important to not only think about the furnace itself, but also the efficiency of the duct work.  Adding insulation or using aeroseal duct sealing are two ways to do this.  If you would like to learn more about energy efficient heating, contact FLAME!