Bosch Greenstar Combination Boiler | Standing Gas Combi-Boiler

From $5,306.04
By Bosch

Product Sizing
  • 100,000 BTU/hr & 2.65 GPM (KWB28)
  • 131,000 BTU/hr & 3.2 GPM (KWB35)
  • 151,000 BTU/hr & 4.0 GPM (KWB42)
Shipping Information
  • This item quallifies for $95 terminal shipping across Canada!
  • This item can be shipped directly to your address for an extra cost; contact our team for a personalized shipping quote.

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No, this product does not have an Energy Star certification.

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Greener Homes Grant Eligibility

No, this product is not eligible for the Canada Greener Homes Grant, except possibly for Northern or off-grid communities.

Click to learn more about the Canadian Greener Homes Initiative and product eligibility here.

  • 10 Year Full Warranty
  • Limited Lifetime Heat Exchanger

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World-wide Best-Selling Boiler Lineup - Gas Combi-Boilers Your Home

Bosch Greenstar Standing Combination Boilers are built using precision German engineering, with Bosch designing and manufacturing all of the key boiler system components. The ultra-quiet Greenstar Combi-boiler is ideal for providing a 2-in-1 heating and domestic hot water (DHW) solution. These boilers can supply hot water for radiant heating systems in your home, including in-floor radiant heating or panel/baseboard radiators, as well as provide up to 4 GPM of on-demand hot water!

The Bosch Greenstar gas combi-boilers are condensing gas, free-standing boilers and achieve efficiency ratings up to 95% AFUE. Bosch has long been known as a quality supplier of everything home appliance, and the Greenstar Combination boilers are no exception - contact us today or order now to start benefiting from a Bosch combi-boiler.

Key features of Bosch Greenstar Floor Standing Combi-boilers include:

  • Guaranteed quality with German engineered and built components
  • Live fire tested and tuned prior to shipment from the factory
  • The perfect combination boiler for:
    • in-floor radiant heating
    • radiant panel heating
    • baseboard heaters
    • hydronic/water furnace home heating
  • A combination boiler to fit any sized home or application:
    • 100,000 BTU/hr heating & 2.65 GPM DHW
    • 131,000 BTU/hr heating & 3.2 GPM DHW
    • 151,000 BTU/hr heating & 4.0 GPM DHW
  • Ease of installation, can operate with or without an indirect storage tanks
  • Use in parallel to your solar thermal hot water system to save money and reduce your energy consumption
  • Integrated low-loss header with a pre-installed supply sensor
  • Low-maintenance, high efficiency Aluminum-Magnesium-Silicon (Al-Mg-Si) Heat Exchanger requires cleaning only once every 5 years
  • Compact floor standing design
  • Built-in circulating pump
  • No de-rating for altitudes up to 6,000 ft (excl. ZWB42 model)
  • Natural Gas & LP (propane) compatible

Safety warning: this is a gas appliance, and as such, requires certified, professional installation. Failure to properly install & commission a gas appliance can lead to serious damage, injury, or death.

More information about Bosch Greenstar standing combi boilers can be found below:

Bosch Greenstar Combi Boilers - floor standing

Greenstar Standing Combi-boiler Dimensions & Sizing:

Model Numbers
Input Heating Capacity (BTU/hr)
Max. DHW (GPM)
Dimensions (H x W x D)


100,000 BTU/hr 2.65 GPM 41" x 19.5" x 21.88"


131,900 BTU/hr 3.2 GPM 41" x 19.5" x 21.88"
KWB42 151,600 BTU/hr 4.0 GPM 41" x 19.5" x 21.88"