A. O. Smith ATM-199X3 Adapt SC Standard Condensing 199,000 BTU Tankless Water Heater with X3 Scale Prevention Technology

<p>The <strong>A. O. Smith ATM-199X3 Adapt SC Standard Condensing Tankless Water Heater</strong> is designed for residential applications that require powerful, efficient, on-demand hot water. With a maximum input of <strong>199,000 BTU/H</strong> and a maximum flow rate of <strong>10.5 GPM</strong>, this unit is suitable for larger homes and higher hot water demand applications.</p><p>This model features <strong>integrated X3 Scale Prevention Technology</strong>, which helps protect the heat exchanger from scale buildup and helps maintain long-term performance. The condensing design includes a <strong>primary copper heat exchanger</strong> and a <strong>secondary stainless steel heat exchanger</strong>, supporting efficient heat transfer and durable operation.</p><p>The ATM-199X3 is <strong>ENERGY STAR certified</strong> with a <strong>0.95 Uniform Energy Factor</strong>. It supports flexible installation options, including indoor installation and outdoor installation with an optional outdoor vent cap kit. Venting options include <strong>2-inch venting up to 50 ft</strong> or <strong>3-inch venting up to 150 ft</strong>, depending on installation requirements.</p><p>The built-in control display allows users and technicians to check operating status, temperature settings, and error codes directly from the unit. For larger hot water applications, up to <strong>12 like units</strong> can be cascaded together using the included cascade cable.</p><p><br></p><p>199,000 BTU/H maximum input</p><p>Up to 10.5 GPM maximum flow rate</p><p>Standard condensing gas tankless water heater</p><p>Integrated X3 Scale Prevention Technology</p><p>ENERGY STAR certified</p><p>0.95 UEF</p><p>Ultra-Low NOx compliant</p><p>Indoor or outdoor installation, outdoor vent cap kit sold separately</p><p>PVC, CPVC, polypropylene, or ABS venting</p><p>2-inch venting up to 50 ft</p><p>3-inch venting up to 150 ft</p><p>Built-in control display</p><p>Primary copper heat exchanger</p><p>Secondary stainless steel heat exchanger</p><p>Cascade capability for up to 12 like heaters</p><p>15-year limited residential heat exchanger warranty</p><p>5-year limited residential parts warranty</p>