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The 510U is well suited for residential/commercial applications such as small restaurants and beauty salons. It features a commercial grade copper heat exchanger with a thicker heat exchanger drum which is suitable for commercial applications or heavier-residential usages such as space heating or domestic recirculation systems. The design allows for a variety of installation options. Complies with Ultra-Low NOx regulations and meets the energy efficiency requirements of ASHRAE 90.1-b 1992. Easy-Link System capable up to 4 units. Multi-Link system capable up to 20 units. The ATO-510U tankless water heater uses up to 199,000 BTU/h of natural gas/liquid propane to deliver an endless supply of hot water for a 2.5 bath home in northern climates and up to a 4 bath home in southern climates (one shower head per bath).

  • Emissions: Ultra-Low NOx
  • Maximum BTUs: 199,000
  • 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: Commercial-Grade Copper
  • Voltage: 120
  • Remote Control: Yes
  • Technology: Non-Condensing
  • Height: 20 1/2"
  • Width: 13 3/4"
  • Depth: 9 1/2"
  • Product Weight: 40lbs/18kg
  • Shipping Weight: 40
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Manuals (3)
Product Type:
Tankless Heater
Fuel Type:
Natural Gas
Inlet Gas Pressure:
Gas Connection:
Water Connection:
Gas Input:
15000 to 190000 BTU/h
Energy Factor:
Installation Type:
Outdoor Only
Max Flow (GPM):
Height (Inches):
Width (Inches):
Depth (Inches):
Weight (lbs):
40 lbs
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