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Acidic Gas Reduction Enables Clean and Efficient Residential Natural Gas Furnace

by Zhiming Gao, Kashif Nawaz, Kyle R Gluesenkamp, Stephen P Kowalski
Publication Type
Journal Name
ASHRAE Journal
Publication Date
Page Numbers
38 to 43

The United States has more than 119 million homes, and 47% of them rely on natural gas as their primary heating fuel. However, most U.S. homes still use noncondensing units with an annual fuel utilization efficiency (AFUE) of ~80%, rather than efficient condensing furnaces. This is due to the high cost of condensing furnaces, which usually use expensive corrosion resistant super-ferritic stainless steel alloy heat
exchangers (HX) to avoid corrosion and fouling acid condensation, along with the cost and difficulty of retrofitting the venting used by the replaced furnace. This article discusses a low-cost acidic gas reduction (AGR) catalyst technology that enables a novel condensing natural gas furnace with an ultraclean (i.e., nearly zero) flue gas and neutral condensate that is environmentally friendly.