How efficient is the Bosch Greenstar 100?

The Bosch Greenstar 100 operates at 95% AFUE (Annual Fuel Utilization Efficiency), meaning 95% of the fuel it consumes is converted directly into heat for your home. This is considered a high-efficiency boiler that can qualify for PSEG Long Island rebates.

How much does the Bosch Greenstar 100 cost to install?

The Bosch Greenstar 100 typically costs $4,000 - $6,500 for a complete installation in Nassau County, NY. This includes the boiler unit, professional installation by NATE-certified technicians, permits, and a standard warranty. Actual costs may vary based on your home's specific requirements, piping condition, and any necessary modifications.

Is the Bosch Greenstar 100 worth it?

With 95% AFUE efficiency, you can expect to save approximately $221 annually compared to an 80% efficient boiler. Key features like Heat-only condensing and Aluminum heat exchanger make it a compelling choice. It's particularly well-suited for mid-size homes upgrading to condensing efficiency.

What is the warranty on the Bosch Greenstar 100?

Bosch provides a 5 years parts warranty and 10 years on the heat exchanger. For the best warranty protection, we recommend registering your boiler within 60 days of installation. Our installations include a workmanship guarantee on top of the manufacturer warranty.

How long does the Bosch Greenstar 100 last?

With proper maintenance, the Bosch Greenstar 100 should last 15-25 years or more. Premium-tier boilers like this one often exceed these expectations due to higher-quality components. We recommend annual tune-ups to maximize lifespan and maintain peak efficiency.

Does the Bosch Greenstar 100 qualify for PSEG Long Island rebates?

Yes! The Bosch Greenstar 100 with 95% AFUE qualifies for PSEG Long Island's efficiency rebates of $500-$1,000. We handle the rebate paperwork for all our Nassau County installations.

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Premium

Bosch Greenstar 100

Model Number: GS100

View on Bosch Website

Efficient heat-only Bosch condensing boiler for retrofit installations.

95% AFUE

Condensing Boiler

57k - 100k BTU

Get Free Quote (516) 345-3911

Technical Specifications

Efficiency (AFUE)95%

Boiler Typecondensing

BTU Output Range57k - 100k BTU

PSEG Rebate EligibleYes ($500-$1,000)

Fuel TypeNatural Gas

Installed Price$4,000 - $6,500

*Prices include equipment, installation, and standard warranty. Actual cost may vary.

Estimated Annual Savings

Compared to an 80% efficient boiler

$221

per year

$4420

over 20 years

Get Your Custom Quote

Ideal For

Mid-size homes upgrading to condensing efficiency

Expert Review: Bosch Greenstar 100

The Bosch Greenstar 100 is the heat-only option for homeowners with existing water heaters. At 95% AFUE, this condensing boiler qualifies for PSEG Long Island rebates while delivering Bosch reliability. The aluminum heat exchanger provides good efficiency at a lower price point than stainless alternatives.

Compact wall-mount design suits retrofit installations where floor space is limited. The digital controls provide straightforward operation with modulating output that matches actual heating demand.

Bosch's extensive parts network through Home Depot Pro and traditional distributors ensures accessible service throughout Nassau County. The 10-year heat exchanger warranty provides solid long-term coverage.

The smaller capacity range (57,000-100,000 BTU) suits typical 1,800-2,800 square foot Long Island homes. For larger homes, consider the Bosch SSB for higher output.

Our recommendation: The Greenstar 100 hits the sweet spot for homeowners wanting Bosch quality in a heat-only condensing boiler. Ideal for retrofit installations where an existing water heater remains in place.