The 410HL is a high-efficiency, two-stage furnace designed by Marathon. It is rated with up to 96% AFUE, or annual fuel utilization efficiency, and meets or exceeds ENERGY STAR® requirements. The 410HL model is available in sizes ranging from 51,000 BTUs (British Thermal Units) to 130,000 BTUs and is designed to provide energy savings and consistent indoor comfort. The furnace is factory set to gas and is designed to deliver warm air throughout the home, while achieving a low decibel level even at its maximum capacity. Its two-stage design operates the first stage at a lower capacity during more mild weather conditions and the second stage at full power only when needed. The 410HL features Marathon's patented heat exchanger design, a stainless steel secondary heat exchanger for longevity and guaranteed performance, plus a variable-speed blower for quieter operation. Additionally, it is also compatible with a whole-home humidifier for added comfort.