High efficiency boiler for heating and storing domestic water and heating water

摘要

The vessel has inner (10) and outer (1) containers and a combustion chamber (18). Heating water is stored in the outer container, and drinking water is stored in the inner container. Hot combustion gases from the chamber are conducted downwards through the space (24) between the containers, in at least container spiral-shaped heat exchange pipe (20). The inner container may be arranged concentrically with the outer container, and may have a smaller height than it. A return-flow connection (2) for heating water may also be arranged in a lower region (9) of the outer container, such as in the lower region of the side wall (3), or in the underside (6).