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OWB Dealer Information

If you sell or plan to sell or lease outdoor wood boilers, this page provides much of the information you need to know to ensure that you are complying with Section 5-204 of Vermont's Air Pollution Control Regulations (APCR).

Vermont Regulations: Vermont adopted a regulation, Section 5-204 of the APCR, that affects OWBs installed after October 1, 1997. Prior to that date OWBs in Vermont were subject only to a generic regulation regarding public nuisances or odors caused by air pollution sources. The most recent change to the Vermont OWB regulation, Section 5-204, became effective October 1, 2009.  Links to the current Phase II regulation and the announcement letter to dealers are listed below.


Section 5-204  Particulate Emission Standards:

Phase I: On or after October 1, 2009 to March 31, 2010, no dealer or manufacturer is allowed to sell or lease an OWB for use in Vermont unless that OWB has been certified by Vermont to meet a particulate emission standard of 0.44 lb/mmBTU of heat input.

Phase II:  After March 31, 2010, no dealer or manufacturer is allowed to sell or lease an OWB for use in Vermont unless that OWB has been certified by Vermont to meet a particulate emission standard of 0.32 lb/mmBTU of heat output. As of March 31, 2010, this standard and rule also applies to outdoor pellet-fired boilers.

Section 5-204 also applies to dealers or manufacturers outside of Vermont that sell OWBs that are destined to be installed in Vermont. The same penalties or other sanctions will apply as for in-state dealers. Manufacturers are required to notify dealers as to which OWB models have been certified for use in Vermont. Certified models will also be posted on this website at: VT Certified OWBS

Set Back Requirement: Section 5-204 prohibits any Phase I OWB from being installed within 200 feet of a residence not owned by the OWB owner or heated by the OWB. In other words, a Phase I OWB must be located more than 200 feet from the nearest neighbor's house that is not served by the OWB. Phase II OWBs are subject to a set back of 100 feet from nearest residence, school or health care facility. Note that accurately determining this distance is critical. The distance is measured from the nearest point on the residence or structure to the nearest point on the OWB, excluding any concrete or other pad. An attached garage is considered part of the residence, but if the garage is detached from the house, it is not considered part of the residence. It is best to add a 10 or 15 foot buffer when determining where to install an OWB. Also, the Division has found that, in many cases, these set backs may not far enough away to prevent nuisance or excessive smoke exposures to neighbors, even with a tall stack.
Stack Height Requirement: Under Section 5-204, if a neighbor's residence is between 200 and 500 feet from an uncertified OWB installed after October 1, 1997, the stack on the OWB must extend higher (in elevation) than the peak of the roof of the tallest structure being served by the OWB. Note that Phase I and Phase II OWBs that comply with the standards set in Section 5-204 (see above) are not required to have taller stacks but we recommend that the stack be tall enough to avoid nuisance to neighbors. Locating the OWB downhill from the house it is heating may make the stack height requirement much more difficult to meet. Here are some examples of stacks that have been raised to comply with this stack height requirement for uncertified OWBs
VT DEC outdoor wood boiler stack VT DEC outdoor wood boiler stack VT DEC outdoor wood boiler stack
Dealer Responsibility:  Under Section 5-204(d) OWB dealers are required to inform OWB purchasers of the regulations. This is documented by having purchasers sign a one page form that tells them about the requirements. Dealers are required to send a signed copy of the form to the Air Pollution Control Division (to the address on the form) before the purchaser takes possession of the OWB.

IMPORTANT: If a dealer does not inform the purchaser of the rules, obtain their signature on the form and submit the form to the Division, the dealer is in violation of Section 5-204 of the APCR. Such a violation may be considered to be more serious when the OWB involved has been illegally installed. The Agency has required dealers to buy back improperly installed OWBs and has fined dealers for not complying with this notification requirement. Please protect yourself by informing the OWB customer and sending-in the forms as required. Dealers or others who install OWBs should also be aware that they may be held in violation of Section 5-204 if the installation does not comply with the regulation as discussed above. Carbonless triplicate forms are available from the Air Quality & Climate Division by calling (802) 828-1288. An example of the Notification Form:


Beyond the Rules: Be responsible and discuss proper operation of their OWBs with the purchasers. Encourage OWB owners to burn only seasoned hardwood in a manner that will minimize smoke emissions. Be aware that some OWBs cause complaints even when installed in compliance with the regulation as discussed above. It is also very important that the OWBs be sized properly for the application. Likewise, installations need to be evaluated to ensure that all piping and pumps are sized properly as dictated by plumbing and heating standards.

Most importantly, be smart. Read the reports and other information on this website. Some OWB manufacturers make unsupported and unrealistic claims about the heating efficiency or capacity or other performance characteristics of their units. Don't further misinformation by repeating these claims to potential buyers. Your customers will appreciate your honesty. We will be posting test data and other information on new, more efficient OWB units as it becomes available.

The Future: Other rules and emission standards being adopted by states or towns could impact on your business because many of the OWBs currently on the market could not comply with reasonable emission standards. However, several OWBs have been shown to meet Vermont's Phase II standard and other manufacturers are rapidly developing cleaner, more efficient devices. As a dealer, you may want to monitor the OWB markets and technologies and consider changing products as appropriate. Selling OWBs that have been proven to be clean and efficient can only improve your credibility with clients. Cleaner models will be highlighted on this website and will be promoted by the U.S. Environmental Protection Agency's Voluntary Program (see discussion and link on this website).



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