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  • Bosch Greenstar 131 Combi Wall Condensing Boiler - ZWB35-3

    - Natural Gas or Propane Gas - Built in Domestic Water - 116000 Btus - 131000 Btus

    Product ID • 773810025600

    Available in Stock: 0

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Bosch Greenstar Combi Wall Condensing Boiler - 131 MBH - NG/LP - ZWB35-3

Bosch Greenstar condensing boilers offer efficiency levels of up to 96.1% efficiency,  Turning 98.7% of the fuel used into heat - a significant upgrade compared to traditional or non-condensing boilers. Used for all type of Hot Water Heating such as Radiant, Baseboards, Radiators and more. The Bosch Greenstar ZWB35-3 has an ASME approved Al-Si heat exchanger constructed of advanced magnesium aluminum-silicon alloy offering increased flexibility versus traditional stainless steel. This highly durable heating block is corrosion resistant and designed to optimize clean burning combustion over an extra large surface area.

Bosch Greenstar ZWB35-3 131 puts out 116,000 Btu's for Heat and 131,000 Btu's for Domestic Hot Water at 96% AFUE rating.

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Technical Specs

Bosch Greenstar ZWB35-3 131 Heat Only Boiler - Techs and Specs

  • Gas
    Natural Gas
  • Maximum Heat Input
    116,000 Btu/hr
  • Minimum heat input
    36,000 Btu/hr
  • Maximum DWH Input
    131,000 Btu/hr
  • Efficiency
  • D.H.W. Minimum Flow Rate
    0.5 GPM
  • Domestic Hot Water Flow - 67 Degree Rise
    3.7 GPM
  • Nominal power supply voltage
    120/60 V/Hz
  • Dimensions
    17.4 Inches L x 33.5 Inches H x 13.9 Inches D
  • Domestic Water Pipe Connections
    3/4 Inch NPT
  • Heating Water Pipe Connections
    1 Inch NPT
  • Gas Pipe Connections
    3/4 Inch NPT
  • Venting Size 2 Inches
    81 Foot Max less elbows
  • Venting Size 3 Inches
    100 Foot Max less elbows
  • Maximum heating pressure
    30 Psi
  • Maximum pressure of domestic water circuit
    150 Psi
  • Weight
    110 Pounds
  • Warranty
    10-year heat exchanger, 5-year parts, and 1-year labor limited warranty
  • * DOE Heating capacity is based on standard test specified by the United States

Bosch Greenstar ZWB35-3 131 Heat Only Boiler - Features

  • With On-Demand Hot Water - Combi - Wall Mounted
  • Turndown to 5 to 1
  • Certified DOE efficiency of 96% Efficiency
  • Outdoor reset with accessory temperature sensor included
  • Built-in boiler circulator pump and Expansion Tank
  • Stainless Steel Flat Plate Heat Exchanger for Domestic Hot Water
  • All models are field convertible from NG to LP with included conversion kit
  • Can be vented with PVC or CPVC

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