What is the function of a water back in a stoker?

The function of a water back in a stoker is primarily to cool the back wall of the furnace and prevent the formation of clinkers. Clinkers are hard, solid masses that can form when certain types of fuel burn. By circulating water in the water back, the temperature of the back wall is reduced, which helps to keep the materials in a manageable state and prevents the clinkers from forming. This cooling effect also protects the structural integrity of the furnace walls, ensuring that it operates efficiently over time.

The other choices, while they represent important functions in different contexts, do not accurately describe the specific role of a water back in a stoker system. For instance, while enhancing combustion and increasing fuel efficiency are common goals in fuel burning systems, they are not direct functions of the water back. Similarly, circulating hot water is a separate aspect of heat management, but it is not the primary purpose of the water back in this specific application.