At the present time GARN WHS units cannot be sold for residential heating in the US. They can only be sold for any nonresidential purpose such as commercial, industrial, small business, shop, process heat or farm outbuilding projects, etc. Both GARN WHS models WHS 1500 and WHS 2000 have lower particulate emissions than allowed under the present EPA emission limits, and were initially approved by the EPA. However, due to a test change (requiring a single piece of additional data) additional testing is required. Refer to Commercial Only article for additional information.
See PDF of GARN Emissions and Efficiency Data.