» Heating Basics » Upgrading Old Equipment » Glossary of Terms	Upgrading Old Equipment Many homes still rely on late model boilers and furnaces to provide heat. In addition to the reliability issues inherent with older equipment, these systems are significantly less energy efficient than the ones available today. For example, many old boilers are rated at only 50-55% AFUE, Annual Fuel Utilization Efficiency, a standard government efficiency rating. In these homes, 45-50 cents of every heating dollar is wasted by system inefficiencies. Compare this to new boiler efficiencies of 84-87%. A new boiler can cut energy costs by 1/3, paying for itself in fuel savings in the first two to three years. And in homes converting from electric to hot water heat, fuel costs can be cut by over 50%.