If you are facing a furnace replacement anytime soon, energy efficiency likely will be one of the main factors when it comes to deciding which furnace to buy.
The rating standard for furnaces and boilers is their Annual Fuel Utilization Efficiency rating. The AFUE rating is achieved by measuring the heat output of the system compared to how much fuel that it uses to produce that heat. So, for example, an older furnace may have had a 70 percent AFUE rating, which meant that 30 percent of the natural gas, propane or oil that it burned in a year was simply vented off through the exhaust system or otherwise lost.
Modern furnaces are achieving much higher efficiency ratings, in part due to stricter standards, but also because of technical advances and a desire for more energy-efficient products. Furnaces sold in Ohio and other Northern states will have to meet at least 80 percent AFUE by 2015, though the current minimum standard is just a little less than that, at AFUE 78 percent.
Some of the technical advances include:
- Electronic ignition, instead of a pilot light. This actually has been the standard for many years already. Pilot lights, as long as they are lit, consume some energy. Not as much as if the furnace were running, but it’s a slow, steady consumption of energy.
- A second heat exchanger, which draws residual heat out of the exhaust from the first heat exchanger, maximizing AFUE. This is included in modern condensing furnaces, the high-efficiency models that fall into the AFUE 90-98 percent range.
- The high-efficiency models also usually feature sealed combustion chambers, to help reduce the amount of heated air that escapes into chimney, to be vented outside the home.
- Sidewall venting, which exhaust the cooler exhaust from a condensing furnace out the side of the house.
These more efficient furnaces help you lower utility bills by reducing the amount of fuel used to provide heat for your home. While furnaces are more efficient, they still require annual maintenance in order to maintain that efficiency.
For more expert information about energy-efficient furnaces or other home comfort-related questions, please contact us at Detmer and Sons, Inc. We have been proudly serving the Dayton area for over 30 years.
Our goal is to help educate our customers in Dayton, Ohio about energy and home comfort issues (specific to HVAC systems).
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