The High Efficiency Bradford White® Infiniti Tankless™ Water Heater Series with SRT™ (Scale Reduction Technology) offers a fully condensing design, an input of 199000 Btu/hr, a fully modulating burner, and exceptional temperature stability. The RTG-199HE achieves a 0.95 Energy Factor. The condensing design utilizes heat from exhaust gases to pre-heat incoming cold water thus increasing efficiency and reducing emissions.