Abstract: A stove for heating a room has three coaxially nested tubular columns formed of superposed rings of ceramic material, these columns defining an innermost channel rising above a combustion chamber to carry off evolving flue gases, an intermediate channel in which the flue gases descend, and an outermost channel which is subdivided by a cylindrical metallic partition into an inner and an outer cylinder section, the former serving as a duct for the escape of the flue gases to an elevated exhaust while the latter is traversed by air to be heated through that partition. Passages connecting the combustion chamber with the inner channel section help entrain an initial gas flow, during start-up, through the descending path of the intermediate channel.