Can I Use Recycled Wood in My Wood Boiler?

Moisture Content Considerations

When using recycled wood in your wood boiler, the moisture content is a crucial factor. Wood with high moisture content can lead to incomplete combustion, reduced efficiency, and increased pollution. The American Society for Testing and Materials (ASTM) recommends that wood for burning should have a moisture content of 20% or less. It’s recommended to use wood with a moisture content between 15% and 20% for optimal performance. To reduce moisture content, you can dry the wood in a controlled environment or use a wood kiln.

Burn Efficiency and Airflow

Recycled wood can be denser and more difficult to burn than fresh wood. To achieve optimal burn efficiency, it’s essential to ensure proper airflow in your wood boiler. This can be achieved by adjusting the airflow dampers and using a sufficient draft to ensure complete combustion. A well-designed wood boiler should have an airflow rate of at least 1.5 cubic feet per minute per pound of fuel burned. You can also use a wood boiler with a high-efficiency design, such as a cyclone or vortex combustion chamber, to improve burn efficiency.

Radiant Floor Heating Considerations

When using a wood boiler for radiant floor heating, it’s essential to consider the thermal mass and heat transfer rate of the system. A well-designed system should have a high thermal mass, such as concrete or tile, to absorb and release heat slowly. You should also ensure that the heat transfer rate is adequate to meet the heating demands of your space. A general rule of thumb is to design the system with a heat transfer rate of 100-200 Btu/h per square foot of floor area. This can be achieved by using a combination of radiant floor tubing and high-temperature hot water circulation.