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  • Bosch Pro Tankless Water Heater - Natural Gas - 520 HN NG

    - 117000 btu

    Product ID • 520HNNG00000

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The Bosch Therm 520 HN in Natural Gas incorporates an evolutionary hydro-power ignition system which allows this tankless water heater to work without a standing pilot, grid connection or battery! A small turbine inside the water heater uses the energy from the flowing water to ignite the burner.

The modulating gas valve then maintains a constant temperature at varying flow rates. This innovative technology, patented by Bosch, makes this an ideal product for installations without access to electricity or regions prone to inclement weather and power outages.

This Bosch Therm 520 HN Natural Gas Tankless Water Heaters must be installed by Professional Installers.

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Technical Specs

Bosch Pro Tankless Water Heater 520 HN NG Specs

  • Type
  • Fuel Type
    Natural Gas
  • Application
  • Max Input (BTU)
  • Min Input (BTU)
  • Capacity at 35 (°F) Rise (gpm)
  • Capacity at 55(°F) Rise (gpm)
  • Intelligent Cascading
  • Min Flow Rate
    0.6 gpm
  • Temp Range (°F) High
  • Thermal Efficiency
  • Installation Options
  • Width
    18 ½ inches
  • Height
    36 ¾ inches
  • Depth
    10 ½ inches
  • Weight (lbs.)
  • Inlet Connection
    ½ inch NPT
  • Outlet Connection
    ½ inch NPT
  • Gas Connection
    ¾ inch NPT
  • Max Water Pressure
    150 psi
  • Min Water Pressure
    13 psi
  • Min NG Presure
    5.7 WC
  • Venting Options
    Galvanized B-Vent
  • Energy Star Rated

Bosch Pro Tankless Water Heater 520 HN NG Features

  • Patented Hydro-power ignition requires no electricity
  • 80%+ thermal efficiency
  • 117,000 BTU maximum input
  • 5.3 gallons per minute capacity at 35F degree rise
  • Endless hot water for 1 application at a time
  • Minimum activation flow rate of 0.6 gallons per minute
  • High to low temperature control
  • Vents with galvanized B vent – natural draft
  • Built for durability and serviceability with 15-year warranty and 20+ year life expectancy

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