Intertherm gas furnaces have an energy efficiency range of 78 percent to 95.1 percent based on the standard Annual Fuel Utilization Efficiency rating. Furnaces that have higher AFUE ratings are higher in efficiency. Consumers can browse the selection of Intertherm furnaces by downloading a brochure on the company's website.
Intertherm gas furnaces meet all federal energy efficiency standards and can be adapted to include an air conditioner. In Northern climates, the minimal AFUE rating for gas furnaces is 80 percent, and consumers should always check energy ratings before purchasing. Intertherm furnaces also have a dual gas shut-off valve that shuts off 100 percent of gas flow when activated.