A hot water device includes a heat exchanger and an apparatus to which the heat exchanger is to be connected. First and second cases for the heat exchanger and the apparatus to which the heat exchanger is to be connected include first and second flange portions laid over each other and welded together. The first and second flange portions are each demarcated into a corner flange portion corresponding to one of first and second corner portions, and into a non-corner flange portion other than the corner flange portion. The non-corner flange portions protrude more to the outside of the first and second cases than the corner flange portions.

A hot water device includes a heat exchanger and an apparatus to which the heat exchanger is to be connected. First and second cases for the heat exchanger and the apparatus to which the heat exchanger is to be connected include first and second flange portions laid over each other and welded together. The first and second flange portions are each demarcated into a corner flange portion corresponding to one of first and second corner portions, and into a non-corner flange portion other than the corner flange portion. The non-corner flange portions protrude more to the outside of the first and second cases than the corner flange portions.

A heat-exchanger unit according to the present invention comprises: a sensible-heat heat-exchange portion arranged in a sensible-heat heat-exchange area for receiving sensible heat generated by a combustion reaction and thereby heating water, the sensible-heat heat-exchange portion having a sensible-heat heat-exchange pipe for receiving the water and causing same to flow through the interior thereof, thereby forming a sensible-heat channel along which the water flows; and a latent-heat heat-exchange portion positioned downstream of the sensible-heat heat-exchange area with reference to a first reference direction along which combustion gas generated during the combustion reaction flows, the latent-heat heat-exchange portion being arranged in a latent-heat heat-exchange area for receiving latent heat generated during a phase change of the combustion gas and thereby heating the water, the latent-heat heat-exchange portion having a latent-heat heat-exchange pipe for receiving the water and causing same to flow through the interior thereof.

The disclosed technology includes a combustion system providing ease of access to components of the combustion system and optimal placement of a burner such that efficient combustion and heat transfer can occur. The combustion system can include an inner tube having a first end and a second end, the second end having a flange with a sensor port, and an outer tube having a first end and a second end. The inner tube can be disposed within the outer tube. The inner tube can have an outer diameter less than an inner diameter of the outer tube, creating a gap between the outer tube and inner tube. An ignitor assembly and a flame sensor assembly can extend through the sensor port and the gap and be positioned proximate a burner.

The present disclosure provides a gas distribution assembly and a water-heating device including the same. The gas distribution assembly for distributing a gas to a plurality of burners includes a manifold unit detachably assembled to an outer surface of a combustion chamber in which the plurality of burners are received, the manifold unit including a plurality of gas nozzles that eject the gas to gas inlets of the burners through an opening of the combustion chamber, and a gas supply unit that is assembled to the manifold unit so as to be separable and that supplies, to the manifold unit, the gas introduced into the gas supply unit. The manifold unit is separated from the combustion chamber and the gas supply unit as needed for replacement.

Provided is a water heater including a burner that receives a supply of combustion air from a fan, a heat exchanger having a heat transfer tube, and a combustion chamber case in which a combustion chamber of the burner is formed in the interior thereof and which is to be capable of guiding combustion gas generated by the burner to the heat exchanger. The water heater further includes a unit case that surrounds the combustion chamber case, and a region on the outside of the combustion chamber case within the unit case serves as an air pressure chamber having a higher pressure than the combustion chamber. Thus, combustion gas leakage to the outside can be prevented or suppressed appropriately by means of a simple configuration.

To provide a water heating apparatus which has a inverse combustion type burner installed within a case for a heat exchanger so as to cause heat to be transferred from an outer peripheral flange of the burner to the heat exchanger case. This water heating apparatus is provided with: a fan for supplying combustion air; a chamber case which is connected to the fan and which has set therein a chamber where an air-fuel mixture is formed; a inverse combustion type burner for combusting the air-fuel mixture supplied from the chamber; a heat exchanger in which combustion gas generated by the burner is introduced into a case where water is heated; and sealing member which is installed between a peripheral flange of the chamber case and a peripheral flange of the case, wherein the burner is set inside the case, and an outer peripheral flange of the burner is anchored to an inner wall surface of the case.

A condensing heat exchanger (100) capable of lowering a requirement for a fan and a water heater having the same, wherein the condensing heat exchanger (100) comprises: a heat exchanger housing (110) having a flue gas inlet (101) and a flue gas outlet (102); and a heat exchange unit (104) located within the heat exchanger housing (110), wherein a sidewall flue gas exhaust channel (105) communicated with the flue gas outlet (102) is provided between the heat exchange unit (104) and an inner sidewall of the heat exchanger housing (110), the heat exchange unit (104) surrounds a flue gas inlet channel (103) communicated with the flue gas inlet (101), the sidewall flue gas exhaust channel (105) surrounds the heat exchange unit (104), and the heat exchange unit (104) is internally provided with a heat exchange flue which communicates the flue gas inlet channel (103) with the sidewall flue gas exhaust channel (105).

A hot water supply device includes a combustion part, a combustion fan, a heat exchange part, a water supply part, a hot water discharge part, and a control part. In the hot water supply device, in a pre-purge step of a heating operation, the presence or absence of a disturbance factor is determined based on rotational responsiveness and deviation of the combustion fan with respect to a scavenging rotation speed. When there is no disturbance factor, in an ignition step, detection of a failure sign is performed based on responsiveness and deviation of the combustion fan with respect to an ignition rotation speed.

Mobile water heating systems for producing hot water are disclosed herein. In one embodiment, a mobile water heating system includes a water heater having an oval-cylindrical shape. The water heater includes a shell, a lid and a water reservoir having a screen. A first heating coil and a second heating coil can extend between the screen and a first cone and a second cone, respectively. A first burner and a second burner can be configured to mix and combust fuel and air and direct the resulting flames through the heating coils. Pall rings can at least partially fill an interior volume of the water heater and the combustion of the fuel and air can heat the heating coils and the pall rings. Water can be heated by being directed through the heating coils and through a water manifold positioned to spray water on the pall rings.