In the midst of an uncertain economy, outdoor wood boilers and wood-fired furnaces have become a way for people to reduce their monthly heating bills and cut heating costs. We have found that we are getting more questions from folks who have never used a wood-fired central heating system, so I thought I would answer some often asked questions to help people better understand the appliances and make informed decisions about their home heating choice.
What is a wood boiler? Wood boilers burn wood and convert the energy in wood to hot water for use as space heating or domestic hot water. They are very similar to a central gas, propane or oil boiler, except the burn wood for fuel.
Will a wood boiler work with my existing forced air heating system? Wood boilers will work with most existing heating systems (e.g. forced air, baseboard, radiant, etc.). They are controlled by the thermostat inside the home.
Are wood boilers and wood furnaces the same? Technically, boilers create hot water and and furnaces create hot air. However, when the terms wood boiler or wood furnace are used, they are often used to refer to the same appliance. The term wood boiler is an East Coast term, while wood furnace is a often used in the Midwest
What is the difference between a traditional wood boiler and a clean technology wood boiler? Over the last few years, the US EPA has been working with manufacturers to promote the development of clean technology wood boilers. These high efficiency units capture most of the heat produced from burning wood and emit 90% less emission than their dirty cousins, the traditional wood boiler. In addition, they use 50-60% less wood, while producing the same amount of heat.
Why are clean technology wood boilers more efficient? Clean technology wood boilers, such as those manufactured by Greenwood Technologies, burn at much hotter temperatures. Through a process called wood gasification, these units burning the wood completely and also burn the smoke and the gases released from the wood. There is little left to exit the chimney as smoke.
How do I know which wood boiler to buy? Look for wood boilers sold with an Orange or White Tag. These appliances are designated by the EPA to be clean burning and meet low emission standards. A short list of manufacturers that currently meet these standards is located at www.epa.gov/woodheaters.
Does my state have regulations for wood boilers? Due to the pollution caused by traditional wood boilers, a number of states including Vermont, New Hampshire and Maine have guidelines for new appliances. Many additional states are also creating model rules. Check with NESCAUM (Northeast States for Coordinated Air Use Management) or you might take a look at the list that the State of Vermont has pulled together here.