Heil has a wide range of gas furnaces ranging from 80% AFUE to 95% AFUE. Various features of Heil gas furnace line-up include variable speed blowers, dual firing rates for higher efficiencie models, hot surface ignition, electronic controls, and a rugged steel cabinet that is corrosion and rust resistant. Warranties for Heil gas furnaces range from 20 year limited warranty on various models of heat exchangers and lifetime limited warranties on other model heat exchangers. Heil Gas Furnace warranties on parts are industry standard 5 years. Diagnostic abilities for better gas furnace troubleshooting Heil has changed hands many time times since its inception but is now owned by United Technologies which is the same parent company that owns Carrier and Bryant.