Flexcore Symmetrical Firetube boilers bring hydronic heating products to unprecedented levels of operating efficiency.

Unlike other manufacturers; from start to finish the Flexcore was designed, developed and engineered by the experts at RBI.

Engineered for performance and longevity the Flexcore utilizes a perfectly temperature balanced heat exchanger that provides not only the highest efficiencies but also a durability beyond that of any competitive firetube boiler on the market.