A heat exchanger and a water heater are provided. The heat exchanger is provided with an auxiliary member including a trunk pipe joint portion joined to a trunk pipe and an extension portion extending from the trunk pipe joint portion toward a plurality of fins. The plurality of fins is provided apart from a sidewall portion so as not to directly contact the sidewall portion of a case, the extension portion of the auxiliary member includes an entry portion that enters between the plurality of fins and the sidewall portion, and a first abutment portion which is provided in the entry portion and abuts outer end portions of the plurality of fins, the first abutment portion is separated from the sidewall portion, and a space portion in which inflow of the heating gas is suppressed is formed between the first abutment portion and the sidewall portion.

A heat exchanging unit exchanges heat between a fluid to be heated and exhaust gas. The heat exchanging unit includes a heat exchange portion, a header portion, and a flow changing portion. The heat exchange portion includes a heat exchange pipe in the interior of which the fluid to be heated flows. The header portion is connected to the heat exchange pipe, the header portion allowing the fluid to be heated to flow from the header portion to the heat exchange pipe or from the heat exchange pipe to the header portion. The flow changing portion changes the state of flow of the exhaust gas introduced into the heat exchange portion.

A condensation tray for condensing tankless water heaters is disclosed. The tray can include a plurality of peaks and valleys. The peaks can divert condensate runoff from a secondary heat exchanger into the valleys so as to prevent the condensate from falling on a primary heat exchanger. The tray includes gas apertures that enable combustion gases to pass through the tray and across the secondary heat exchanger. Overhangs on the peaks can prevent the condensate from draining through the gas apertures.

A heat transfer fin (1) includes a plurality of heat-transfer-tube insertion holes (10) aligned in a single stage, a downstream cut portion (3) formed so as to be recessed toward an upstream side of a gas flow passage of combustion exhaust gas, a downstream flange (13) formed on a peripheral edge of the downstream cut portion (3) so as to protrude from one surface of the heat transfer fin (1), and a plurality of first protruding pieces (4a) (4b) (4c) formed between the heat-transfer-tube insertion hole (10) and the downstream flange (13) so as to protrude alternately from both surfaces of the heat transfer fin (1).

The disclosed technology includes a fluid heating device including a frustoconical combustion chamber and a heat exchanger that can include heating tubes. The combustion chamber can have a first end and a second end that is in fluid communication with the heating tubes. The surface area of the second end of the combustion chamber can be larger than the surface area of the first end of the combustion chamber.

Swimming pool or spa gas heaters, cabinets, water header manifolds, and heat exchangers include: gas heaters having an air gap between a cabinet and combustion chamber to reduce heat transfer to sides of the cabinet; gas heaters having a user interface that is repositionable on a top panel; gas heater cabinets including a removable top panel that can be hung on a side panel; gas heaters having a built-in dual junction box; gas heaters having a top-accessible igniter and burner that are interlocked to maintain positioning thereof; adaptable water manifolds including connectable inlet and outlet fittings that adjust effective inlet and outlet positions; heat exchangers having a plurality of tube-and-fin subassemblies arranged in a semi-circular configuration; and water manifolds including internal cartridges that divide the water manifold into a plurality of chambers for improved circulation through a heat exchanger.

Swimming pool or spa gas heaters, cabinets, water header manifolds, and heat exchangers include: gas heaters having an air gap between a cabinet and combustion chamber to reduce heat transfer to sides of the cabinet; gas heaters having a user interface that is repositionable on a top panel; gas heater cabinets including a removable top panel that can be hung on a side panel; gas heaters having a built-in dual junction box; gas heaters having a top-accessible igniter and burner that are interlocked to maintain positioning thereof; adaptable water manifolds including connectable inlet and outlet fittings that adjust effective inlet and outlet positions; heat exchangers having a plurality of tube-and-fin subassemblies arranged in a semi-circular configuration; and water manifolds including internal cartridges that divide the water manifold into a plurality of chambers for improved circulation through a heat exchanger are disclosed.

A heat exchanger includes front and rear walls forming a flue gas space such that a fluid flowing through a channel formed in the front and rear walls can exchange heat with flue gas in the flue gas space, in use. An entirety of the back wall extends along a first plane, and the back wall is provided with a back fin. The front wall includes a lower portion extending upwardly along the back wall, and an upper portion extending upwardly from an upper end of the lower portion and outwardly away from the back wall to form a combustion space of a flammable gas between the upper portion and the back wall. The upper portion is provided with a front fin. The front and back fins are arranged symmetrically with respect to a virtual line along which the flammable gas is to be injected into the combustion space.

An aspect of the present disclosure provides a flow channel cap plate that constitutes a combustion chamber assembly including a combustion chamber and a plurality of insulating pipelines disposed on left/right side surfaces of the combustion chamber, the flow channel cap plate forming an insulating flow channel by covering the front surface of the combustion chamber, the flow channel cap plate including an inlet part including an inlet, and an inlet flow channel cap covering the front surface of the combustion chamber, an inlet space part is formed by covering the front surface of the combustion chamber with the inlet flow channel cap, the inlet is an entrance of the insulating flow channel, the plurality of insulating pipelines include a plurality of inlet insulating pipelines, and the inlet space part is a space that communicates the inlet with the plurality of inlet insulating pipelines.

A combustion apparatus includes a combustion part, a blower fan, an ignition device, and a control part. The control part selectively performs continuous combustion in which the combustion part is operated to burn continuously and intermittent combustion in which a combustion period and a non-combustion period of the combustion part are repeatedly provided. When the continuous combustion is stopped, the control part extinguishes the combustion part and operates the blower fan to perform a scavenging operation. When the combustion period in the intermittent combustion is ended, the control part extinguishes the combustion part and operates the blower fan to perform a scavenging operation in the non-combustion period. A total air blowing amount of the blower fan in the scavenging operation during the non-combustion period is set to be less than a total air blowing amount of the blower fan in the scavenging operation when the continuous combustion is stopped.