Energy-saving environment-friendly domestic heating boiler

The invention relates to a domestic heating boiler. The domestic heating boiler comprises a boiler body shell and a base, and an upper water tank, a water jacket and a coal furnace are arranged in an area enclosed by the boiler body shell and the base. The coal furnace comprises a furnace wall and a hearth, and a heat collecting plate is arranged at the upper ends of a coal furnace and a hearth heat insulation layer. An area enclosed by the water jacket and the heat collecting plate as well as an area enclosed by the boiler body shell, the base, the upper water tank and the water jacket form a flue gas chamber jointly. The flue gas chamber is divided into three areas which are an outer flue gas chamber body, a middle flue gas chamber body and an inner flue gas chamber body respectively, the area enclosed by the heat collecting plate and the water jacket refers to the inner flue gas chamber body, the area between the upper top face of the water jacket and the lower bottom face of the upper water tank refers to the middle flue gas chamber body, the area positioned among the boiler body shell, the water jacket and the upper water tank refers to the outer flue gas chamber body, and the middle flue gas chamber body is communicated with the outer flue gas chamber body and the inner flue gas chamber body. A smoke exhaust pipe is arranged below the outer flue gas chamber body, and an automatic control valve is arranged on the smoke exhaust pipe.