Boiler

摘要

The heating boiler has the cover elements (2) that are locked at both ends of a combustion chamber (1). A helically coiled gap heat exchanger (3) is provided to enclose the housing which consist the cover elements and a casing portion (4). A rectilinear tube element (5) is formed outside the housing of the gap heat exchanger. The superior end portion is formed in an outer cylinder circumference of the gap heat exchanger. The through hole (6) for the rectilinear tube element, is formed at the cover element.