For decades, the standard in furnace design was to vent the exhaust gases created by burning a fuel out of your house through a vent pipe. The problem with this approach is that these exhaust gases are what your furnace uses to heat your home, and any heat left in the exhaust gases is heat which cannot be used to heat your home. In other words, a conventional furnace will never be as efficient as it could be. A condensing furnace has an improved design, which can allow it to use nearly all the heat in the exhaust gases.
The Basics of Furnace Design
The three key components of a furnace are the burner, the heat exchanger, and the fan. The burner, no surprises here, is where the fuel your furnace burns is combusted. The fuel then converts into super-heated gases, which travel to the heat exchanger. A heat exchanger will have several channels, which are heated as the the exhaust gases travel through them. Your furnace fan then pushes air over the heat exchanger, which accomplishes two things:
1) The air absorbs heat from the heat exchanger, which heated air can then be used to heat your home.
2) The air flowing over the exchanger cools it, thus preventing damage to the exchanger.
How a Condensing Furnace Is Different
The heat exchanger in a conventional furnace is designed to leave just enough heat in the exhaust gases so that they will rise out of your home through a vent pipe. Because of this a conventional furnace will never be more than 83%, and depending on the age of your furnace, might be as little as 56% efficient. A condensing furnace will have a second heat exchanger, which will extract so much heat from the exhaust that it converts back to a liquid and drains out of your furnace through a tube to a drain in the floor. This designs makes the furnace as much as 98% efficient.
If you have an older furnace in your home, you are paying too much. For example if you have a 56% efficient furnace, $44 of every $100 that you spend on heating your home is simply wasted. You might as well be burning money to heat your home. By installing a highly efficient furnace, you can decrease this waste. As long as your savings are more than your furnacing costs, installing a condensing furnace is worth it. Talk to a furnace installer to see if a condensing furnace is right for you. For more information, go to sites that focus on HVAC innovations.