ARLINGTON, Va. - The Air-Conditioning, Heating, and Refrigeration Institute (AHRI) is warning consumers about the dangers of unauthorized and unapproved altering of any gas-fired heating appliance.

According to AHRI, manufacturers must use specific engineering and design knowledge to develop gas-fired heating appliances that operate safely and properly under a variety of conditions.

“The product designs are tested and certified by third-party independent testing agencies, like CSA International, ETL/Intertek, and Underwriters Laboratories for compliance with nationally recognized voluntary consensus safety standards,” said the association. “Any unauthorized modification to a gas-fired appliance, no matter how minor, can alter the design and compromise the safety of that unit.”

One example cited was an alteration that changes the combustion process possibly causing carbon monoxide (CO) emissions that exceed the limits specified in the safety standards. Modifications should only be made that are authorized by the original equipment manufacturer (OEM) or other recognized authority and performed by qualified service personnel.

The association also warned that consumers should beware of companies that offer to make, or instruct consumers about how to make, modifications to various appliances without expressed, written authorization of the OEM; and advised them to always check with the OEM or their local representative to ensure that a modification is authorized.

“Any unauthorized modification to a gas-burning appliance voids its safety certification and may expose consumers to a risk of property damage, personal injury, or even death,” said Frank A. Stanonik, AHRI chief technical advisor. “AHRI is committed to providing consumers with information on the proper installation and safe and efficient use of gas-fired appliances.”

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Publication date:12/07/2009