AFUE Efficiency

AFUE is an abbreviation for Annual Fuel Utilization Efficiency and is mostly used to measure a furnace's efficiency when it comes to heating. The measurements takes the amount of heat that is actually delivered in your home and compares it to the amount of energy, or fuel, that was consumed to produce the desired output. An easy way to look at this would be to use an AFUE of 80% as an example. A furnace with a 80% AFUE rating simply converts 80% of the fuel into heat. Now you may ask, what happens to the other 20%? Well, all 100% of the fuel is used to create heat, but a certain percentage is lost out of the chimney of the home - this equals the remaining 20%.

If you were to go shopping for a furnace today, you would only be able to choose between three different types. The basic three include AFUE ratings at 80%, 93% and 95%. Now you might be sitting there thinking "Why don't I just get one with the best AFUE rating?" That's an extremely valid question, but sometimes things arent always what they seem.

The 80% AFUE furnace is the least expensive furnace on the market, but pricing isn't the most important factor. These type of gas furnaces can only be vented through an exit in the roofing. While they are the least expensive, these types of furnaces are also the least efficient. This means that while you are saving on single purchase cost, you will most likely end up spending more in the long run. Just think of it this way, 20% of every single dollar you spend heating your home will be lost through exhaust.

Now we move onto the 93% gas furnace, which has quickly become one of the more popular utilities for homeowners. There are two main reasons for the increase in popularity for this type of furnace. The first being flexible venting capabilities. Where the 80% AFUE furnace can only vent through roofing, the 93% uses PVC piping and can be vented in multiple configurations. This means you can vent the exhaust out of your sidewall or even through your basement. The other reason this model has gained so much popularity is due to its cost savings potential. While the unit costs around 40% more than the 80% unite, the 93% AFUE equates to about 14% more savings than its 80% counterpart. This translates to significant energy and cost savings over an extended period of time.

The final, and most efficient, choice for home heating is the 95% AFUE furnaces. Now when looking at AFUE ratings you might not consider this model as that big of an increase over 93%, but at a closer look you will see that this type of furnace completely outclasses any of its competitors. These furnaces are considered to be "ultra-high" efficiency and are often complimented by variable speed blowers, gas valves and a variety of other components. The additional functionality on these furnaces is what makes them more efficient, comfortable and nearly silent. The 2% increase in AFUE efficiency is considered to be the tip of the iceberg and many owners have even reported complete silence when their units were running. While these systems are considered to be super efficient, they tend to be on a higher price point than any other available furnaces. They run around 30% more than the 93%, but the added comfort and long term efficiency benefits should be considered.