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Why Newer Furnaces Are So Much More Energy Efficient


I don’t like to brag, but I know a lot more about heating technology than your average dog. (To be fair, I’m sure firehouse dogs know a lot more about fire engine technology than me.) Hanging around on the couch in our offices, I get to hear a lot of the discussions that our skilled technicians have about working on furnaces and air conditioners. So when I say that I want to talk to you about that old gas furnace in your home, remember that I do have some credentials.

Okay, so about that furnace… if you’ve had it for more than 15 years, it’s probably costing you far more to run than it should. It isn’t only age that makes it less efficient. It’s also that newer furnaces have much higher energy efficiency thanks to advances in heating technology. Here are some reasons that high efficiency furnaces drain so much less power:

  • A second heat exchanger: A standard furnace has a heat exchanger where combustion gas gathers and heats up the walls, which then heat up the air. The exhaust gases are then sent outside through a vent. But special “condensing” furnaces contain a second heat exchanger that takes the exhaust gas and then condenses it, getting even more heat out of it. Less waste, more heating!
  • Electronic ignition: Does your furnace use a pilot light that stays on through winter? That drains away a lot of energy. Thanks to the electronic ignition systems in a new furnace, you don’t need a pilot light at all!
  • Variable-speed fans: Fans in conventional furnaces have two settings, “on” and “off.” Variable speed fans have different settings, and they automatically switch to lower ones when necessary to help conserve energy.
  • Sealed combustion: The standard older furnace draws the air that it needs for combustion from inside the house. A newer “sealed combustion” furnace instead draws it from outside, and this makes it more energy efficient. It’s safer, too.
  • They’re just built better: Okay, this isn’t very tech-talky, but new furnaces just are better made, and a better made machine will waste less power.

Are you ready to change out your wasteful old furnace for a high-efficiency unit? Then call MK Russell & Abbott. We serve Greenback, TN and also Blount County.