March 16, 2015

Condense your Carbon Footprint with Condensing Boilers

Of the many ways to heat a home, one of the most common is with a hot water boiler. If you are looking to enhance the efficiency of your home heating system, it’s important to understand exactly how a boiler works.

Let’s start with the basics: A boiler burns fuel to heat water that is then distributed to radiators which heat a desired space. In the process of combustion, CO2 and water vapors are expelled as flue gases. Typically, these gasses are around 350-400 C – what a waste of heat!

What is a Condensing Boiler?

A condensing boiler integrates additional components, primarily a second heat exchanger, to recover some of that heat from the exhausted gasses. Just as liquids absorb heat when converting to gasses (think boiling water), gasses expend heat when condensing back into liquid form. By causing the flue gasses to condense on the secondary heat exchanger, a condensing boiler harnesses the expended heat from the condensation process and uses it to condition the water going to your radiators.

How do Condensing Boilers save energy?

Not only is less heat wasted in flue gasses, but as these boilers recover heat and reuse it, less fuel is used in the combustion process because the water being heated has been preconditioned to a higher temperature.

By utilizing condensing technology, manufacturers are able to produce boilers that exceed 90% efficiency ratings, some even pushing levels as high as 98%, compared to conventional boilers that rate between 70-86% efficiency. This means that instead of wasting up to thirty cents for every dollar spent, you’ll be wasting between two and ten cents.

How much will this actually save me?

Not every boiler will see such dramatic decreases in energy usage and carbon footprint, so it is important to determine the condition and efficiency of your current boiler before deciding if an upgrade to a condensing unit is right for you. For example, the 4% efficiency gain you get from replacing an 86% efficient boiler with a 90% efficient boiler may not justify the higher purchasing cost of the replacement if the current boiler is relatively new itself. Similarly, an older, 70-80% efficient unit would see considerable savings by making the upgrade. is an excellent resource to help determine your potential energy cost savings.

Ben Owens is a Brand Specialist for, a leading retailer of heating and cooling equipment. For more information on which boiler is right for your home, view the boiler selection guide at


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