What is the safety issue related to unvented heaters and fireplaces?

Improper use of unvented heating units can cause carbon monoxide poisoning and oxygen depletion, which can contribute to sickness and even death. These unvented heating units come in many shapes and sizes, including wall, kerosene and torpedo-style heaters, and are particularly dangerous when installed in dwellings, such as homes, garages, hunting cabins or ice fishing shacks.

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Who does this safety issue concern?

Anyone who owns or operates an unvented heater or fireplace should be aware of the possible hazards related to these heating units.

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What does the Wisconsin code say regarding the use of unvented heaters and fireplaces?

The State of Wisconsin prohibits the use of unvented heaters and fireplaces in single-family homes built after June of 1980, and all commercial buildings, apartments and condominiums regardless of construction date. The specific rule governing unvented heaters is found in the Wisconsin Department of Commerce Heating, Ventilating, and Air Conditioning Standards: Chapter Comm 23.04(1b). "The use of unvented furnaces and space heaters fueled by natural gas, kerosene, alcohol or other fuel shall be prohibited due to concerns about oxygen depletion; contamination from carbon monoxide, carbon dioxide, nitrogen dioxide, formaldehyde and other combustion related contaminants; and water vapor buildups."

The code is not retroactive and does not directly apply to homes built before 1980. For homes built before June of 1980, the State of Wisconsin has passed on the jurisdiction to local municipalities or major fuel suppliers. Many municipalities and fuel suppliers have prohibited the use of unvented heaters and fireplaces in any home regardless of the date of construction. In addition, any alterations made to the fuel piping system or appliances must comply with the above rule, along with any other applicable codes.

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How does the code of unvented heaters and fireplaces affect WPS customers?

As a major fuel supplier, WPS prohibits the use of unvented heaters and fireplaces in any home regardless off the date of construction. Unvented fireplaces and heaters found to be connected to the WPS gas system will be turned off, disconnected from the piping system, and "Caution Tagged" as an immediate hazard and code violation. A copy of the "Caution Tag" will be sent to the proper code enforcement agency.

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How do I get more information?

For more information on unvented heaters, please reference: Wisconsin Department of Commerce Heating, Ventilating, and Air Conditioning Standards: Chapter Comm 23.04(1b); Contact your local building inspector; or email WPS at customerservice@wisconsinpublicservice.com.

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