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Coeur D’Alene & Spokane Area

Serving The Greater Coeur D’Alene & Spokane Area


ACI Northwest Blog

Kellogg Heating Q/A: What Exactly Are High Efficiency Boilers?

As a Kellogg resident you have already read plenty about how energy costs are rising. You know plenty well that heating your home is a substantial expense, and that the cost of running a boiler is constantly on the rise. That whole array of topics has been more than adequately covered.

So rather than spend more time telling you what you already know, this post is about one of the solutions to combat the high costs of home heating: high efficiency boilers. As technology has gotten better, so have boilers become more efficient at providing heat. It stands to reason that a more efficient boiler is one that costs less to run…but what does “efficient” really mean in the context of boilers? What makes a boiler “high efficiency”?

What Is a High Efficiency Boiler?

All boilers are rated according to a standardized system of rating efficiency, called the Annual Fuel Utilization Efficiency (AFUE). Essentially, this rating tells you how much heat energy is produced by a boiler compared to how much energy it draws. The higher a boiler’s AFUE rating, the more efficient it is.

For a boiler to be called high efficiency, it must carry an AFUE of at least 90%. For basis of comparison, older systems carry an AFUE of about 70%, while mid-efficiency systems run at about 82%.

In addition, a high efficiency system has a second heat exchanger for capturing and condensing flue gases, as well as a closed combustion system.

These three things — an AFUE of 90% or above, condensing flue gases and closed combustion – define a so-called “high efficiency” boiler.

Getting More Efficient

To go the high efficiency route, the most obvious option is to replace your current boiler with a high efficiency unit. But what if you have a fairly new boiler that is not ready to be replaced yet?

In that case, you can retrofit your existing boiler with high efficiency equipment. It won’t be quite the same as getting a top-of-the-line high efficiency boiler, but it will produce high efficiency results without costing as much.

The initial investment in a high efficiency boiler can be costly, but the savings over time in heating bills make it well worth the expense.  Call ACI NW with any questions about boilers.

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