Efficiency Tests
The Highest Efficiency. The Fewest Emissions.
Only One Outdoor Wood Furnace Has Been Able to Make Both Claims.

At Central Boiler, we relied upon scientific testing to accurately verify the performance of our furnace and to provide a comparison using accredited test procedures. In the first-ever comprehensive tests of outdoor wood furnace efficiency and emissions, The Classic left the competition behind. In this testing of the five leading outdoor wood furnace brands, The Classic was found to be the most efficient. It was also found to have the fewest emissions. Data from these accredited laboratory reports of 1995 were used in these comparisons. All models tested in this comparison were new regular production units at the time of testing. Since this testing, the Classic Central Boiler firebox has been changed to the Ripple Top® (shown below) design to even further increase performance. Some other manufacturers may have changed their firebox designs since 1995. The firebox designs that were tested are shown at the right of the following charts. The delivered efficiency, stack temperature and emissions charts below show the results of accredited laboratory test data, collected from identical tests performed using the same wood and test methods. As of May of 2004 there have been no other published results from test performed using uniform test methods to accurately compare performance of outdoor wood furnaces. Others have made claims of performance but have chosen not to compare side by side to any Central Boiler Classic Furnace in published, unbiased, accredited laboratory testing.

We continually strive to lead the industry in producing the most efficient outdoor wood furnaces with low emissions. High efficiency and low emissions mean lower operating costs, less wood usage, and more heat out of your wood. It also means cleaner air. That's good for you, and for all of us.

How The Classic Gets More Heat From Your Wood

Why is The Classic more efficient? The key is more complete combustion, the ability to collect more heat, and deliver it to the home or building being heated.

Inefficient Firebox Design
Inefficient designs burn more wood and deliver less heat. Why? Because intense heat is not trapped or transferred to the water that's pumped to your home. Instead, the heat rises to the top of the firebox and escapes through the chimney -- wasting heat and increasing emissions. This is proven by higher stack temperatures.

The Classic Ripple Top® Firebox Design

The heavy-gauge steel firebox in The Classic, with our automatic draft control, is designed to get the most heat out of your wood. A water baffle traps heat and gases in the top of the firebox. The Ripple Top® firebox design creates a high-temperature secondary burn area for more complete combustion. It also allows for optimum heat transfer surfaces in the most intense heat collection area so more heat can be transferred more efficiently to the water that is pumped to your home. The firebox is enclosed in a water jacket to keep the metal from overheating or warping. And it's surrounded by waterproof, airtight urethane foam insulation.

Firebox Designs Tested

To learn more about the environmental impact of The Classic, see our Environmental Advantages page.
 For more information about this option, please contact your local dealer or browse our furnace models to find which best fits your application. Please review the Owner's Manual for installation and operation specifications.

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A safe, efficient outdoor furnace that can provide 100% of your heating needs.Outdoor Boilers of Europe distributes the Classic Outdoor Wood Furnace. Heats multiple buildings, hot tubs, pools, greenhouses, domestic water and more.

While burning wood indoors can mean many problems, there is an alternative... The Classic outdoor wood furnace from Outdoor Boilers of Europe. The Classic eliminates the problems associated with indoor burning and allows you to get even more benefits from wood heat. This outdoor furnace can actually improve the indoor environment in your home or business, while eliminating the time-consuming chore of tending a traditional wood stove. In addition, tests show that the Classic is the most efficient outdoor wood furnace, with the fewest emissions.