Abstract: A valve device includes: a case having a valve chamber and first to third water communication ports communicating with the valve chamber; first and second valve bodies disposed in the valve chamber; and a shaft body connected with the first valve body. The first valve body is rotated about a central axis of the shaft part. The second valve body is rotated about the central axis together with the first valve body. When rotated about the central axis in a first angle region, the first valve body changes a first flow rate, i.e., a flow rate of water between the first and third water communication ports, and a second flow rate, i.e., a flow rate of water between the second and third water communication ports. When the first valve body is rotated about the central axis in a second angle region, the second valve body changes the second flow rate.

Abstract: A heating and hot-water supply apparatus includes a combustion means, a heat exchanger, a circulation passage, a circulation means, a bypass passage, a distribution means, a hot-water supply heat exchanger, a water entry passage, a hot-water supply passage, and a control means. The circulation passage connects an external heating terminal and the heat exchanger. The water entry passage supplies water of an external hot-water supply pipe and an external water supply pipe to the hot-water supply heat exchanger. The control means controls the distribution means to be adaptable to each of a heating operation and a hot-water supply operation. The control means prioritizes the hot-water supply operation when there is a hot-water supply request for warm water use in addition to a heating request, and prioritizes the heating operation when there is a temperature-maintaining request for maintaining a temperature of the hot-water supply pipe in addition to the heating request.

Abstract: An air blowing fan supplies an amount of air corresponding to a fan rotation speed to a burner during operation. A check valve has a biasing force that closes an exhaust vent, and is opened and closed in accordance with a relationship between a gas pressure in an exhaust passage and the biasing force. A controller performs a failure diagnosis for detecting an open failure of the check valve when a phenomenon in which the gas pressure is lower than a predetermined normal pressure range is detected in a case where the fan rotation speed is within a predetermined diagnosis rotation speed region. The diagnosis rotation speed region is set within a rotation speed range in which a degree of opening of the check valve changes with an increase in the fan rotation speed when the check valve is normally opened and closed.

Abstract: 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.

Abstract: A flame rod of a hot water apparatus is attached to a side wall part of a case that surrounds a combustion region such that an insulator part is positioned on a downstream side of a burner port plate of a burner in a combustion gas flow direction. A core wire part includes an extending part extending from the insulator part toward the burner port plate, and a tip-side part positioned closer to a tip of the core wire part than the extending part. In the combustion gas flow direction, the tip-side part of the core wire part is opposed to at least one of burner ports, and the extending part is not opposed to any of the burner ports.

Abstract: A premixing device includes first and second fuel gas outlets through which fuel gas is capable of flowing out to first and second flow paths partitioned by a partition wall part of a premixing flow path, using a negative pressure generated by an air flow in the first and second flow paths. The premixing device further includes: a first blade part that is provided in the first flow path and includes the first fuel gas outlet provided facing a downstream side in an air flow direction; a flapper that has an opening degree changing according to an air flow rate and opens and closes both the first flow path and the first fuel gas outlet; and a pair of fin parts that protrude at the flapper to sandwich the first fuel gas outlet and the first blade part, and form a gap with respect to the first blade part.

Abstract: This method of manufacturing an outer case for a hot water unit involves a pressing step for subjecting a flat metal plate (30a) to press processing to form a component part (3) of the outer case (C), and a painting step for painting text, symbols, figures or patterns on the component part (3), wherein the painting step involves an inkjet printing step for forming an inkjet printing layer (4) by performing inkjet printing on the flat metal plate (30a). The pressing step is performed after the inkjet printing step, and after the pressing step, there is further a clear coating step for forming a clear layer (5) on the inkjet printing layer (4).

Abstract: A premixing device includes: a gas flow passage forming member in which an x direction is used as an axial length direction, and a Venturi-shaped gas flow passage into which air can flow in from the outside is formed inside; and a blade portion positioned in the gas flow passage, extending in a y direction, and equipped with a fuel gas outlet. The blade portion includes first and second blade portions spaced apart from each other in a z direction, and an air flow path near the center through which a part of the air flows is formed between these first and second blade portions. At least one of a pair of surfaces of the first and second blade portions facing each other is equipped with an inner bulging portion that bulges in the z direction so as to squeeze a part of the air flow path near the center.

Abstract: Provided is a blowing device capable of improving a noise reduction effect as compared with a conventional case, and a combustion device including the blowing device is provided. In a rear side shroud of an impeller configuring a blowing device, a first inclined surface portion that is inclined so as to be located frontward toward the radial outer side is formed in a front surface portion of the rear side shroud in a region close to the outer peripheral edge, while a second inclined surface portion that is inclined so as to be located rearward toward the radial outer side is formed in a front surface portion of the rear side shroud in a region closer to the center than the first inclined surface portion.

Abstract: A hot water supply device and a hot water supply system are provided. A controller actuates a circulation pump at a constant output and actuates a heating mechanism for heating by a combustion mechanism when an instantaneous hot water operation is started in response to a temperature drop of a fluid while hot water supply of a hot water supply tap is stopped, until a minimum drive time elapses. The minimum drive time is set based on a flow rate detection value of a flow rate detector under a condition that the circulation pump is actuated at a predetermined constant output and an instantaneous hot water circulation path is formed.

Abstract: A heating and hot-water supply device includes a combustion means, a heat exchanger, a circulation passage, a circulation means, a bypass passage, a distribution means, a hot-water supply heat exchanger, a water supply passage, a hot-water supply passage, and a control means. The heat exchanger heats a heating heat-medium to a target heat medium temperature. The distribution means distributes the heating heat-medium to the circulation passage and the bypass passage. The control means is capable of adjusting a distribution ratio of the distribution means to be adaptable to a heating operation, a hot-water supply operation, and a simultaneous heating and hot-water supply operation. At the time of transition from the heating operation to the simultaneous heating and hot-water supply operation, in a case where the heating terminal for performing heating is a warm air heater, the control means raises the target heat medium temperature.

Abstract: A heat exchanger includes a plurality of heat transfer tubes housed in a predetermined case, a connecting tube body for connecting the plurality of heat transfer tubes, a predetermined tube expansion portion provided on each heat transfer tube, a first peripheral wall portion provided on the tube expansion portion, and a second peripheral wall portion that is positioned on an end portion of the connecting tube body and fitted to the tube expansion portion, wherein the first and second peripheral wall portions have different sectional shapes and are fitted together in a partial contact state including predetermined contact and non-contact portions. According to this configuration, the heat transfer tubes can be fixed to a side wall portion of the case and the connecting tube body can be connected to the heat transfer tubes easily and appropriately.

Abstract: 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.

Abstract: An air blower and a combustion device including the air blower are provided. An air blower includes an impeller housed in a casing and rotating. The impeller includes multiple blades to form multiple inter-blade passages, and a central space portion. When the impeller rotates, air flowing into the central space portion through an air intake port of the casing passes through the inter-blade passages at an outward side. To reduce noise generated when the air passes through the inter-blade passages, each blade includes: multiple first concavo-convex portions, with a first surface side being concave and a second surface side on the other side being convex, from among a first and a second surface corresponding to a front and a rear surface of each blade; and multiple second concavo-convex portions, with the second surface side being concave and the first surface side being convex, contrary to the first concavo-convex portions.

Abstract: 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.

Abstract: A linked hot water supply system includes: multiple combustion hot water supply devices arranged in parallel between a water supply pipe and a hot water supply pipe; and a control means, changing a number of operated units of the hot water supply devices to adjust a heating capacity according to a hot water consumption. The hot water supply devices each includes a water passing volume detection means detecting a water passing volume of tap water introduced from the water supply pipe and an inlet water filter installed to an introduction part of the tap water from the water supply pipe. If the hot water supply devices are operating at a same time, the control means makes a determination on blockage of the inlet water filter installed in each of the hot water supply devices by comparing the water passing volumes of the hot water supply devices in operation.

Abstract: A metal bend pipe having a bend portion bent in a semi-circular arc shape is provided, in which an identification part that enables one of the two end portions of the bend portion to be identified as the bending-start side or the bending-end side is provided, and the identification part is integrally formed as a protruding and/or recessed three-dimensional region. Thus, it is possible to easily and reliably identify which of the two end portions of the bend portion is the bending-start side or the bending-end side.

Abstract: In a pipe machining apparatus A, a region of a part including a first pressure contact part 61a which comes into pressure contact with a first portion 11a of a pipe P in a lower clamper part 6 of a clamping device C serves as a first movable clamper part 61 which is separate from a different region 63 of the lower clamper part 6, and the pipe machining apparatus A includes a first displacement member 8A that is able to displace the first movable clamper part 61 in a predetermined first direction D1 after machining of the pipe P ends. According to such a constitution, a pipe machining apparatus capable of appropriately resolving aggravation of workability of removing a pipe caused by a part of the pipe which comes into pressure contact with a lower clamper part of a clamping device can be provided.

Abstract: A heat exchanger includes a case, a first and second heat exchanger disposed inside the case, a partition member disposed inside the case, and a duct. The case has a first side wall and a second side wall spaced apart from and facing each other in a first direction, a third side wall and a fourth side wall spaced apart from and facing each other in a second direction orthogonal to the first direction, and a bottom wall. A gas outlet communicating with an interior of the case is formed in the first side wall. The first heat exchanger is farther from the bottom wall than the second heat exchanger in a third direction orthogonal to the first and second directions. The second heat exchanger includes meandering heat transfer tubes meandering within a plane orthogonal to the first direction and overlapping along the first direction.

Abstract: A tank includes: a bowl-shaped head having a peripheral wall whose base end side is open; and a tubular body member having an end in an axial length direction joined to the head. The peripheral wall of a region of the head close to a base end is an inclined peripheral wall whose inner diameter increases toward the base end. The end of the body member is inserted inside the inclined peripheral wall of the head and is joined to an inner peripheral surface of the inclined peripheral wall via a weld. A mark available for use in determining a position of the end of the body member is provided in a position on an outer peripheral surface of the body member on a central part side of the body member in the axial length direction with respect to the head and away from the end by a predetermined dimension.