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Maryland State Government Maryland Department of the Environment

Small Wood Boilers

Maryland Certified Small Wood Boilers

The following table lists small wood boilers that have been approved for sale and use in Maryland. As of April 1, 2010, the Department will no longer certify Phase 1 models (0.60 pounds of particulate matter per million Btu heat input rating). Phase 1 units may not be offered for sale or installed in Maryland after this date. Phase 1 units installed before March 31, 2010 may continue to be operated in Maryland. Phase 2 models, which meet a minimum 0.32 pounds of particulate matter per million Btu, are available for sale and installation, and may be operated in Maryland.

Phase 2 Models (April 1, 2010 and Newer)

Manufacturer

Model Name
& Number

Heat Output
Rating

Maryland
Certification Letter

Central Boiler Maxim M250

0.06

 pdf

Central Boiler E-Classic 1400

0.27

 pdf

Central Boiler E-Classic 1450

0.18

pdf 

Central Boiler E-Classic 2300

0.31

 pdf

Central Boiler E-Classic 2400

0.12

pdf

Central Boiler E-Classic 3200

0.08

pdf

Earth Manufacturing Klear Sky 400 Series

0.29

pdf

 

Hardy Manufacturing Model KB125

0.31

pdf

 

Hardy Manufacturing Model KB165

0.31

pdf 

Hardy Manufacturinig Model KBP270

0.20

pdf

Hawken Energy Wood-Fired Hydronic Heater Model GX10

0.14

pdf

Heatmor 200-SSR II

0.18

pdf

Heatmor Boiler Model-200 SSP

0.07

pdf

Heatmor Boiler Model-400-4S

0.28

pdf

Heat Smart Plus (Piney Manufacturing, Ltd.) Portage and Main Optimizer 250 Outdoor Wood-Fired Hydronic Heater

0.23

pdf

 

Heat Smart Plus (Piney Manufacturing, Ltd.) Portage and Main Optimizer 350 Outdoor Wood-Fired Hydronic Heater

0.30

pdf

 

Heat Smart Plus (Piney Manufacturing, Ltd.) Portage and Main Outdoor Furnaces - Enviro Chip 500 Series

0.19

pdf

 

Heat Source 1 Earth Energy Series 190 Boiler 0.19

pdf

Pro-Fab Emprye Elite
XT100

0.24

pdf

 

Pro-Fab Emprye Elite
XT 200

0.31

pdf

 

Pro-Fab Empyre Pro Series Model 400

0.31

pdf

Pro-Fab Empyre Pro Series Model 200

0.27

pdf

SteelTech Inc. Model G100

0.074

pdf

 

SteelTech Inc. Model G200

0.066

pdf

 

SteelTech Inc. Model G400

0.23

pdf

 

Wood Doctor Outdoor Furnaces HE5000 Solid Fuel Outdoor Hydronic Heater

0.32

pdf

The U.S. Environmental Protection Agency (EPA) maintains a list of small wood boilers that meet Phase 1 and Phase 2 emission standards. MDE has contacted manufacturers of small wood boilers and requested supporting documentation in order to certify small wood boilers for use in Maryland that meet the applicable emission standards.Please contact manufacturers if a particular model of interest is not listed among Marylands list of approved small wood boilers.

Emission Standards

Small wood boilers (under 350,000 Btu/hr) made available for sale and use in Maryland after April 1, 2010 must meet an emissions performance standard of 0.32 pounds of particulate matter per million Btu of heat output.

Labeling Requirements

As of April 1, 2009 small wood boilers made available for sale and use in Maryland must include an affixed permanent label that includes:

  • the month and year of manufacture;
  • model number or name;
  • serial number;
  • date of certification;
  • thermal output rating in million Btu per hour; and
  • tested emission limit for particulate matter in pounds per million Btu.

Operating Requirements

Owners and operators of new and existing small wood boilers are required to use only clean wood, wood pellets made from clean wood, or heating oil as fuel. The use of garbage, tires, asphalt products, manure and animal carcasses as fuel is prohibited. Click here  for a complete list of prohibited fuels.

The Department recommends the following best practices for all small wood boilers:

  • Have units installed by a certified plumber, electrician or professional.
  • Follow manufacturer's instructions, applicable ordinances, and best burn practices.
  • Use only dry, seasoned wood for fuel. Do not use treated wood, household garbage, paints, etc. as fuel.
  • Consider your neighbors. Operating small wood boilers in residential neighborhoods, especially those that are densely populated is not recommended.
  • Conduct yearly maintenance of units, which includes having units professionally cleaned and inspected to keep them in working order.
  • Consider replacing your older existing small wood boiler with a cleaner, more efficient heating system.

Enforcement

In addition to the State, local and county governments have the authority to enforce certain provisions of this regulation and address citizen nuisance complaints that arize from the operation of small wood boilers. Local and county governments also have the authority to implement additional rules or restrictions.

Additional Resources

Hearth, Patio & Barbecue Association - Best Burn Practices
U.S. EPA - Burn Wise Program
U.S. EPA - Particulate Matter
U.S. EPA - Air Toxics
U.S. EPA - List of Hydronic Heaters
Burning Issues

 

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