How Efficient are Outdoor Wood Furnaces?

How Efficient are Outdoor Wood Furnaces?


Outdoor Wood Furnaces has been keeping families toasty warm for decades already. But now more than ever, using outdoor wood boilers is beyond question the best alternative for heating American homes as the price of electricity and natural gas is unceasingly rising. But...

How Efficient are Outdoor Wood Furnaces?

Outdoor wood furnace efficiency ratings are measured in many ways and this can be deceptive. Some rating methods are hard to understand. Most commonly, “efficiency” is measured based on “What percent of BTUs in the fuel goes into your building?” With all fuels, some of the heat from the fuel must go up the chimney to eliminate contaminants, but this “lost heat” needs to be minimized. If 100,000 BTUs of wood fuel is put into an outdoor furnace, and 80,000 BTUs of heat are sent to the home, then that outdoor furnace efficiency can be rated at 80%. Most of the high-efficiency outdoor boilers achieve 80% or more efficiency.

How to Make Your Outdoor Wood Furnace more efficient?

The quality of woods you burn will affect the efficiency of your outdoor furnace. The energy stored in various types of wood can vary significantly. Also, another factor that affects the available heating BTUs in your wood is its moisture content. ​Freshly cut green wood contains up to 50% moisture. That means that 50% of the weight of the wood is water.

When you try to burn green wood, you must first use up your precious BTUs from your fire to boil off the water in greenwood. Those are BTUs that could have gone into your home but instead are wasted. But properly seasoned wood contains only 20% moisture.


So the 3 Most Important Steps are as follows: 

  1. Split
  2. Stack
  3. Cover

Click here to know more about these three important steps.

Choose the Best Underground Insulated PEX

Choosing the best Underground Insulated PEX is as important as choosing the best Outdoor Wood Boiler. No matter how efficient your outdoor wood boiler if the Underground Insulated PEX you install is not the BEST in the market, then you are just wasting your money.

Introducing the World's Best Insulated PEX: Insulated PEX Heat Mizer Brand. Our Insulated PEX Heat Mizer Brand is no doubt the best there is in the market.

  • Forever Waterproof design
  • Lowest Heat Loss Ever - Less than one degree of heat loss over 200 feet!
  • Industry Leading Warranty - Full Replacement Coverage, including LABOR!
  • Perfect Performance Record - Over 1 Million Sold and ZERO Failures
  • Experts Agree - Our proprietary design has been PERFECTED for over 30 years!

Watch the video below and learn more about the best Insulated PEX!


Our goal at is to help you realize the best return on your investment!  We have invested MILLIONS in research, testing, and proving our designs and methods. We want YOU to benefit from all we have learned!

You made a big investment in your outdoor furnace system so you deserve to realize a great return on that investment!

Refund policy

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