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The 110U Series is great for apartments, one bath homes in cold climates, condos and summer cabins. The design allows for a variety of installation options. Complies with Ultra-Low NOx regulations and meets energy efficiency requirements of ASHRAE 90.1b-1992. The ATI-110U tankless water heater uses up to 140,000 BTU/h of natural gas/liquid propane to deliver an endless supply of hot water for a 1.5 bath home in northern climates and up to a 2.5 bath home in southern climates (one shower head per bath). The ATI-110U is ENERGY STAR® qualified with a Uniform Energy Factor of 0.81. With an industry leading 15-year limited warranty, the ATI-110U tankless water heater provides years of hot water through innovation and quality.

  • Maximum BTUs: 140,000
  • Minimum BTUs: 15,000
  • UEF: 0.81
  • Limited Heat Exchanger Warranty: 15 Years
  • Limited Parts Warranty: 5 Years
  • Water Connection Location: Bottom
  • Water Connection Size: 3/4"
  • Heat Exchanger: Copper
  • Voltage: 120
  • Digital Display: Yes
  • Technology: Non-Condensing
  • Height: 20 1/2"
  • Width: 13 3/4"
  • Depth: 10"
  • Product Weight: 38lbs/17kg
  • Shipping Weight: 39
  • Vent Type: Direct Vent
  • Vent Length: 60 feet at 4 diameter
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Manuals (3)
Product Type:
Tankless Heater
Fuel Type:
Natural Gas
Inlet Gas Pressure:
Installation Type:
Indoor Only
Gas Connection:
Water Connection:
Gas Input:
15000 to 140000 BTU/h
Max Flow (GPM):
Energy Factor:
Width (Inches):
Height (Inches):
Depth (Inches):
Weight (lbs):
38 lbs
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