A.O. Smith® 100123378 ATI-540H Tankless Water Heater, Natural Gas

AOSATI540HN MFG #: 100123378
  • Commercial / Residential / Dual: Dual
  • Energy Factor: 0.95
  • Flow Rate: 10 gpm
  • Heating Capacity: 199,000 BTU/hr
  • Indoor / Outdoor: Indoor
  • Ultra Low NOx: Yes
  • Vent Size: 3 in, 4 in
  • Vent Type: Power Direct
  • Condensing / Non-Condensing: Condensing
  • Dimensions: 17-3/4 in W x 11-1/4 in D x 23-5/8 in H
  • Gas Connection: 3/4 in NPT
  • Ignition Type: Electronic Spark
  • Manufacturer: A.O. Smith
  • Manufacturer #: 100123378
  • Pressure Rating: 15 to 150 psi
  • Series: ATI-540H
  • Water Connection: 3/4 in NPT
Ultra-Low NOx gas tankless water heaters with condensing technology featuring an unprecedented 0.95 Energy Factor which lowers operating costs and is environmentally friendly.

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A.O. Smith® Tankless Water Heater, Series: ATI-540H, 199000 Btu/hr Heating, Natural Gas, 3/4 in NPT Gas Connection, Electronic Spark Ignition, Power Direct Vent, 3 in, 4 in Vent, Condensing/Non Condensing: Condensing, 10 gpm, 0.95, 3/4 in NPT Water Connection, 15 to 150 psi, Ultra Low NOx: Yes, Indoor/Outdoor: Indoor, 17-3/4 in W x 11-1/4 in D x 23-5/8 in H, Dual
  • Features
  • Ultra low NOx emissions
  • Primary heat exchanger is constructed of a commercial grade copper that is more resilient to erosion
  • Copper is 25x better at heat transfer than stainless steel thus stabilizing outgoing water temperatures quicken
  • Secondary heat exchanger is made of type 316L stainless steel to protect against corrosion
  • Air-fuel ratio (AFR) sensor, exhaust and water temperature safety control, overheat cut-off fuse
  • Exhaust, 3 in PVC venting up to 70 ft or 4 in PVC venting up to 100 ft
  • Provides flexible venting with PVC, CPVC or ABS pipe for intake and exhaust (solid core only)
  • Category III or IV venting can be used
  • Certified from sea level to 10100 ft elevation
  • Indoor model - Built-in temperature controller and advanced diagnostics to simplify troubleshooting