The Eccotemp 20 HI Indoor Natural Gas Tankless Water Heater is one of the largest indoor models of the Eccotemp tankless line. Rated at an impressive 6.0 gallons per minute (gpm) and 150,000 BTU per hour, the Eccotemp 20 HI-NG can meet all the hot-water needs of a standard home or apartment with one or two bathrooms, as well as smaller commercial applications. The compact, wall mounted Eccotemp 20 HI-NG is powered by natural gas. The Eccotemp 20 HI-NG is ready to install with its 110/120-volt UL listed power cords powering the internal exhaust fan and digital display. With its fully automated control system, the Eccotemp 20 HI-NG only pulls about 12 amps during the operation, making it an ideal choice for any standard-sized home. Includes Z-Vent 3-inch Verticall Vent Kit (exhausts through the roof).