Abstract: A combustion apparatus includes a burner (11), a heat exchanger (12) accommodated in a casing (20), an exhaust passage (22B) provided to one side surface side of the casing (20), and an exhaust resistance member (5) having a plurality of ventilation ports (50) through which combustion exhaust gas passes, wherein at least one part of the ventilation ports (50) has an elongated hole shape extending in the flow direction of the combustion exhaust gas from beneath the casing (20) to the exhaust passage (22B).

Abstract: In a steam generator, a flow resistance adjusting unit for a primary cooling water is provided in an inlet nozzle provided at an incoming water chamber or an outlet nozzle provided at an outgoing water chamber.

Abstract: A water heater is provided in which neutralization process of drain is not required and an excellent heat efficiency is achieved. A route of exhaust gas which is passing through the main heat exchanger 18 is divided into a first exhaust gas chamber 23 having a secondary heat exchanger 19 and a second exhaust gas chamber 24 having a drain evaporator. Because of this, hot exhaust gas which is passing through only the main heat exchanger 18 flows into both the secondary heat exchanger 19 and the drain evaporator 100. Therefore, in the secondary heat exchanger 19 exhaust gas heat can be efficiently recovered by utilizing the hot exhaust gas, and in the drain evaporator 100 drain can be evaporated efficiently by utilizing the hot exhaust gas.

Abstract: A water outlet pipe leading to a feed water tank is connected to a separator disposed downstream of an evaporator. A heat exchanger and a first control valve are disposed in the water outlet pipe, the valve being influenced by the level in the separator 20. In the heat exchanger heat is transmitted from the water flowing out of the separator to the feed water flowing to the heating surfaces of the vapor or steam generator. Between the heat exchanger and the first control valve, a bypass pipe branches from the water outlet pipe and contains a second control valve which is also influenced by the level in the separator. The bypass pipe leads into a condenser. A considerable proportion of the water leaving the separator is discharged via the bypass pipe to the condenser as a result of the pipe branching off upstream of the first control valve.

Abstract: A liquid heating apparatus according to the present invention comprises a cylindrical outer shell, an inner shell consisting of a cylindrical body whose upper and lower portions are respectively provided with an enlarged flue chamber having a cross-sectional area remarkably larger than that of said cylindrical body, said inner shell being disposed within said outer shell so as to provide a space forming a water jacket between the two shells, a fire chamber formed by closing said cylindrical body at above said lower enlarged flue chamber, an insert hole for burner which penetrates said inner and outer shells and opens into said fire chamber, a rising heated gas chamber which is disposed above said fire chamber so as to communicate with it as well as said upper enlarged flue chamber, a falling heated gas space formed by intercommunicating said upper and lower enlarged flue chambers by means of plural smoke pipes penetrating the water jacket formed in between said outer shell and inner shell, and a flue outlet p