A water tank assembly of a heating device includes a plurality of side plate assemblies. A heat exchange chamber is formed by enclosing at least the plurality of side plate assemblies. The water tank assembly further includes a heat exchange pipe disposed in the heat exchange chamber and having an inlet end and an outlet end, and a leak-proof plate disposed in the heat exchange chamber and connected to one side plate assembly of the plurality of side plate assemblies. A mounting hole is formed at the leak-proof plate. At least one of the inlet end or the outlet end of the heat exchange pipe passes through the mounting hole and the one side plate assembly.

A water heater has a primary heat exchanger having a first heat transfer tube, a secondary heat exchanger having a second heat transfer tube connected with the first heat transfer tube and being located higher than the first heat transfer tube, and an outflow path connected to an outflow-side end portion of the first heat transfer tube. The outflow path has an offset flow path portion including a rising portion which rises upward or obliquely upward from a connecting portion of the outflow path and the outflow-side end portion of the first heat transfer tube or from the vicinity of the connecting portion, the offset flow path portion being offset at a position higher than the outflow-side end portion. When hot water supply is temporally stopped, the water at high temperature in the first heat transfer tube flows into the offset flow path portion, thereby inhibiting such a disadvantage that water having a lower temperature than a target temperature is supplied because of a natural convection at the time of restarting hot water supply.

A water heater includes a primary heat exchanger, a secondary heat exchanger disposed above the primary heat exchanger, a flow path member, and a flow restriction member. The secondary heat exchanger includes a case and heat transfer pipes arranged in the case. The case includes a wall having a gas inlet through which combustion exhaust gas discharged from the primary heat exchanger is introduced into the case. The flow path member connects the primary heat exchanger and the secondary heat exchanger and is disposed adjacent to the gas inlet and is configured to introduce the combustion exhaust gas discharged from the primary heat exchanger into the secondary heat exchanger through the gas inlet. The flow restriction member is disposed on the wall of the case to suppress upward flowing of the combustion exhaust gas that is introduced into the case through the gas inlet.

A water heater defines a vertical direction and includes a tank for holding water. The water heater further includes a shroud positioned over the tank along the vertical direction. The shroud defines a chamber over the tank, and includes a partition wall that divides the chamber into first and second chamber portions. The water heater includes an evaporator disposed within the first chamber portion, and a compressor disposed within the second chamber portion. The partition wall is positioned between the evaporator and compressor within the chamber of the shroud. Further, the shroud defines a vent extending through the shroud to the chamber of the shroud. In one embodiment, the vent is contiguous with the first chamber portion.

The invention provides a condensing boiler 100 including a heat exchanger 160, the heat exchanger including at least one fluid flow cassette 162a, 162b, 163a, 163b, 164a, 164b, each cassette comprising first 181 and second 182 sheets, wherein at least the first sheet has corrugations 185, 186, 187 along a length of the sheet so as to form a number of grooves extending across a width of the sheet, wherein the second sheet is attached against the first sheet so as to enclose the grooves to form a number of fluid flow passageways 193 extending across a width of the cassette in between the first and second sheets, and wherein the cassette is substantially curved across its width such that the fluid flow passageways are substantially curved along their length. The invention also provides a method of manufacturing a heat exchanger or condensing boiler.

A water heater defines a vertical direction and includes a tank for holding water. The water heater further includes a shroud positioned over the tank along the vertical direction. The shroud defines a chamber over the tank, and includes a partition wall that divides the chamber into first and second chamber portions. The water heater includes an evaporator disposed within the first chamber portion, and a compressor disposed within the second chamber portion. The partition wall is positioned between the evaporator and compressor within the chamber of the shroud. Further, the shroud defines a vent extending through the shroud to the chamber of the shroud. In one embodiment, the vent is contiguous with the first chamber portion.

Modifications convert an existing single-pass boiler to operate with a multi-pass combustion gas flow through the flue passages of the heat exchanger of the boiler. A diverting target wall is arranged partway along the length of the original combustion chamber, and an upper draft diverter is arranged in a flue collector chamber above the flue passages, to divert some or all of the combustion gas into a multi-pass flow pattern through several flue passages of the heat exchanger in series. The modifications may further include changing the nozzle oil delivery rate and cone angle, the oil supply pressure, the draft conditions, and others. Heat extraction from the hot combustion gas to the boiler water is increased, exhaust gas temperature is decreased, and overall efficiency is increased, to result in a fuel and cost savings.

A heat exchanger comprising a mixture inflow unit into which a mixture of air and fuel is introduced, a burner for combusting the mixture introduced through the mixture inflow unit, a sensible-heat exchange unit that is disposed around the burner, a latent-heat exchange unit in which heat is exchanged between combustion gas having passed through the sensible-heat exchange unit and a heating medium, and a combustion gas discharge unit is provided.

A heat exchanger comprising a mixture inflow unit into which a mixture of air and fuel is introduced, a burner for combusting the mixture introduced through the mixture inflow unit, a heat exchange unit that is disposed around the burner, and a combustion gas discharge unit for discharging the combustion gas having passed through the heat exchange unit is provided.

A water heating appliance includes a fluid inlet and a fluid outlet, and a heater that heats a fluid that is delivered to a fixture. First and second wall panels define a perimeter wall that extends around the heater. A first top panel is attached to the first wall panel and has a seat that partially defines a dividing edge. A second top panel is disposed on a second wall panel. The second top panel includes a mount that further defines the dividing edge. The mount engages the seat to define an enclosed position. The seat extends below the mount. The dividing edge defines a cutout portion. The fluid inlet and the fluid outlet pass through the cutout portion. The second top panel is separable from the first top panel and the wall panels define a minor access aperture.