The Hans CB-Series comprises a range of combination boilers that are unique in design. They have smoke and water tubes in the same boiler, making them a combination boiler. It has a water wall, which can be three, four, or five-sided, that is externally joined with the boiler shell. The water wall acts as the furnace, and a furnace bed, along with an airbox, is provided for proper combustion of the combustible. The water present in the tubes of the water wall is heated by the flue gases produced during combustion. These gases then travel through the tubes of the attached shell. The flue tubes of the shell open in the smokebox and continue the steam generation process in the boiler. This design combines the advantages of a water tube and a smoke tube-type boiler.