The last time the U.S. government raised furnace efficiency standards was 1987, building science writer Allison Bailes reports.
Earlier this yea, the U.S. Department of Energy announced a proposal to increase the minimum required percentage of Annuel Fuel Utilization Efficiency (AFUE) from 78 percent to 92. If enacted, it would effectively get atmospheric combustion furnaces off the market.
Read more on the issue at Energy Vanguard.