A.O. Smith

A.O. Smith® ATI540HX3-N ProLine® XE Tankless Water Heater, Condensing Ultra-Low NOx Indoor 199,000 BTU, Natural Gas

AOSATI540HX3N MFG #: ATI-540HX3-N
A.O. Smith® ATI540HX3-N ProLine® XE Tankless Water Heater, Condensing Ultra-Low NOx Indoor 199,000 BTU, Natural Gas
  • Fuel Type: Natural Gas
  • Heating Capacity: 199,000 BTU/hr
  • Vent Type: Power Direct
  • Digital Display: Yes
  • Dimensions: 23-5/8" H x 11-1/4" D x 17-3/4" W
  • ENERGY STAR® Certified: Yes
  • Heat Exchanger: Commercial Grade Copper
  • LEED Rating: 1.5
  • Manufacturer: A.O. Smith
  • Manufacturer #: ATI-540HX3-N
  • Mounting Type: Wall
  • Secondary Heat Exchanger: Stainless Steel
  • Series: ATI
  • Technology: Condensing
  • Type: Space Saving
  • Vent Length: 70 feet at 3 diameter / 100 feet at 4 diameter
  • Voltage Rating: 120 V
  • Water Connection Location: Bottom
  • Water Connection Size: 3/4 in
The 540X3 series is well suited for residential applications. A. O. Smith has combined water heating and treatment in a product designed to revolutionize tankless water heating. Our new condensing gas tankless line features X3™ Scale Prevention Technology to last three times longer than other tankless models without X3™ Technology. Complies with Ultra-Low NOx regulations. The 540X3 utilizes commercial-grade copper alloy for the heat exchanger tubing. Certified up to 10,100 ft. altitude.

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ATI540HX3-N 199k BTU Natural Gas Tankless Water Heater with X3™ Anti-Scale Technology, Indoor
  • Features
  • X3TM Scale Prevention Technology - Extends life of unit up to 3 times longer and no annual descaling required.
  • Includes freeze, overheat, surge protection and troubleshooting diagnostic codes.
  • The primary heat exchanger is constructed of commercial-grade copper, which is stronger than standard copper and more resilient against erosion
  • Condensing models feature 316L stainless steel secondary heat exchanger, providing additional protection against corrosion