ProLine Residential Gas Tankless Water Heaters

Residential Gas Tankless Water Heaters

A. O. Smith offers a complete line of natural gas and liquid propane tankless water heaters for continuous hot water needs. Choose from ENERGY STAR® certified condensing models or non-condensing models.

A. O. Smith
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Adapt™+ Premium Condensing Ultra-Low NOx 199,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology
Energy Star
Adapt™+ Premium Condensing Ultra-Low NOx 199,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology Model ATHR-199X3 100
  • ENERGY STAR® certified (0.95 UEF)
  • 199,000 BTU input
  • 15-Year Warranty
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Adapt™+ Premium Condensing Ultra-Low NOx 180,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology
Energy Star
Adapt™+ Premium Condensing Ultra-Low NOx 180,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology Model ATHR-180X3 100
  • ENERGY STAR® certified (0.95 UEF)
  • 180,000 BTU input
  • 15-Year Warranty
|
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Adapt™+ Premium Condensing Ultra-Low NOx 160,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology
Energy Star
Adapt™+ Premium Condensing Ultra-Low NOx 160,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology Model ATHR-160X3 100
  • ENERGY STAR® certified (0.95 UEF)
  • 160,000 BTU input
  • 15-Year Warranty
|
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Adapt™ SC Standard Condensing Ultra-Low NOx 199,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology
Energy Star
Adapt™ SC Standard Condensing Ultra-Low NOx 199,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology Model ATM-199X3-N 100
  • ENERGY STAR® certified with a UEF of 0.95
  • 199,000 BTU input
  • 15-year limited warranty
|
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Adapt™ SC Standard Condensing Ultra-Low NOx 180,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology
Energy Star
Adapt™ SC Standard Condensing Ultra-Low NOx 180,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology Model ATM-180X3-N 100
  • ENERGY STAR® certified with a UEF of 0.95
  • 180,000 BTU input
  • 15-year limited warranty
|
View Model
Adapt™ SC Standard Condensing Ultra-Low NOx 160,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology
Energy Star
Adapt™ SC Standard Condensing Ultra-Low NOx 160,000 BTU Natural Gas Tankless Water Heater with X3® Scale Prevention Technology Model ATM-160X3-N 100
  • ENERGY STAR® certified with a UEF of 0.95
  • 160,000 BTU input
  • 15-year limited warranty
|
View Model
ProLine® XE Ultra-Low NOx Indoor Natural Gas Tankless Water Heater with X3® Technology
ProLine® XE Ultra-Low NOx Indoor Natural Gas Tankless Water Heater with X3® Technology Model ATI-540HX3-N 100
  • 199,000 BTU input
  • 15-Year Warranty
|
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ProLine® XE Ultra-Low NOx Outdoor Liquid Propane Tankless Water Heater with X3® Technology
Energy Star
ProLine® XE Ultra-Low NOx Outdoor Liquid Propane Tankless Water Heater with X3® Technology Model ATO-540HX3-P 101
  • ENERGY STAR® certified
  • 199,000 BTU input
  • 15-Year Warranty
|
View Model
ProLine® XE Ultra-Low NOx Outdoor Natural Gas Tankless Water Heater with X3® Technology
Energy Star
ProLine® XE Ultra-Low NOx Outdoor Natural Gas Tankless Water Heater with X3® Technology Model ATO-540HX3-N 100
  • ENERGY STAR® certified
  • 199,000 BTU input
  • 15-Year Warranty
|
View Model
ProLine® XE Ultra-Low NOx Indoor Liquid Propane Tankless Water Heater with X3® Technology
ProLine® XE Ultra-Low NOx Indoor Liquid Propane Tankless Water Heater with X3® Technology Model ATI-540HX3-P 101
  • Endless Hot Water
  • 199,000 BTU input
  • 15-Year Warranty
|
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ProLine® XE Ultra-Low NOx Outdoor Natural Gas Tankless Water Heater with X3® Technology
ProLine® XE Ultra-Low NOx Outdoor Natural Gas Tankless Water Heater with X3® Technology Model ATO-340HX3-N 100
  • Endless Hot Water
  • 180,000 BTU input
  • 15-Year Warranty
|
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ProLine® XE Ultra-Low NOx Outdoor Liquid Propane Tankless Water Heater with X3® Technology
ProLine® XE Ultra-Low NOx Outdoor Liquid Propane Tankless Water Heater with X3® Technology Model ATO-340HX3-P 101
  • Endless Hot Water
  • 180,000 BTU input
  • 15-Year Warranty
|
View Model
ProLine® XE Ultra-Low NOx Indoor Natural Gas Tankless Water Heater with X3® Technology
Energy Star
ProLine® XE Ultra-Low NOx Indoor Natural Gas Tankless Water Heater with X3® Technology Model ATI-340HX3-N 100
  • ENERGY STAR® certified
  • 180,000 BTU input
  • 15-Year Warranty
|
View Model
ProLine® XE Ultra-Low NOx Outdoor Natural Gas Tankless Water Heater with X3® Technology
Energy Star
ProLine® XE Ultra-Low NOx Outdoor Natural Gas Tankless Water Heater with X3® Technology Model ATO-240HX3-N 100
  • ENERGY STAR® certified
  • 160,000 BTU input
  • 15-Year Warranty
|
View Model
ProLine® XE Ultra-Low NOx Indoor Natural Gas Tankless Water Heater with X3® Technology
ProLine® XE Ultra-Low NOx Indoor Natural Gas Tankless Water Heater with X3® Technology Model ATI-240HX3-N 100
  • Endless Hot Water
  • 160,000 BTU input
  • 15-Year Warranty
|
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Showing 1-15 of 18
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A. O. Smith water heaters are available through your local plumbing professional.
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