Bosch Greenstar FS Boiler Overview

The Bosch Greenstar FS is a condensing gas boiler with an efficiency of 95% AFUE. The FS is a floor-standing unit available in combi or heat-only models and is an Energy Star Most Efficient 2016 product. The unit’s aluminum-silicone heat exchanger offers greater flexibility than stainless steel and is coated to prevent scale build-up and improve efficiency while increasing the life of the boiler. Its compact design and built-in frost protection feature offer greater installation options, and all models are available as propane or natural gas. Combi models feature a domestic hot water output of up to 4 GPM, and all models are insulated to provide low operating sound levels.

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Other Greenstar FS Reviews

In reply to a post from a homeowner asking about floor-standing boilers on, another homeowner stated that he had a Greenstar FS and is very pleased with it. A homeowner on with a complaint about noise and vibration from his unit was advised that the problem was almost certainly due to air in the lines.

Greenstar FS Warranty

Product registration is required within 90 days of installation for maximum warranty coverage. The warranty for the Bosch Greenstar FS boiler is comprised of the following:

  • Limited lifetime heat exchanger warranty, pro-rated after the 10th year
  • Limited 5-year parts and labor warranty

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