Atmospheric hot-water boiler with coal-saving, smokeless and dust-free

The utility model discloses a constant-pressure hot-water boiler, which is characterized in that a furnace shell has the structure with square front and circular rear. A motor of an axial flow type combustion-supporting device is arranged in an upper groove at the bottom of a flue; a long axis of the motor runs through a hole pipe of an inhalator dust remover to be connected with smoke exhaust blades; the hole pipe of the inhalator dust remover, an upper and a lower end plates are sealed and fixed in the groove at the bottom of the flue; a steam pipe and a hole in the tangential direction of the wall of the hole pipe are fixed; the furnace shell and a flat pin of a furnace liner are fixed on a bottom board. The utility model has the characteristics that the furnace shell with square front and circular rear reduces the destructive power of inner combustion expansion force to the furnace shell; the axial flow combustion-supporting device and the inhalator dust remover play the role of supporting combustion and removing dust; the furnace shell and the flat pin of the furnace liner fall to the ground, and thus the service life of the boiler is prolonged.