Abstract: [Problems] A flat burner elongated in the longitudinal direction has, at an upper end thereof, a main burner port (63) and a flame retention port (64) positioned at least on laterally one side of the main burner port (63). The flat burner uses hydrogen-containing fuel as a fuel. Flash back is prevented at the flame retention port in which the gas ejection speed becomes relatively small. [Solving Means] A lean fuel-air mixture which is leaner in fuel concentration than a theoretical fuel-air ratio is ejected from the main burner port (63) and a gas containing only fuel is ejected from the flame retention port (64). In addition, the height, on the side of the main burner port (63), of the upper end of the flame retention port (64), is made lower than the height of the upper end of the main burner port (63).

Abstract: The air-fuel mixture permeable member is disposed to overlap that surface of the burner frame which lies opposite to the burner body. The fixing frame is disposed so as to be fixed to the inner peripheral portion of the enclosing frame part of the burner frame by pinching the air-fuel mixture permeable member between the inner peripheral portion and the fixing frame. The air-fuel mixture permeable member has an extended part protruding outward beyond the fixing frame so as to cover by this extended part an outer peripheral portion of the enclosing frame part.

Abstract: An outer peripheral edge part of the air-fuel mixture permeable member is connected to a portion away outward by a predetermined distance from an inner peripheral edge of the burner frame. Between the burner frame and the air-fuel mixture permeable member a clearance reaching the inner peripheral edge of the burner frame is secured at a position inward of the outer peripheral part of the air-fuel mixture permeable member. Preferably, a bent edge part formed on an inner peripheral edge of the burner frame, in a manner to be bent toward the air-fuel mixture permeable member. The amount of the air-fuel mixture to flow into the clearance is limited to a smaller amount.

Abstract: A heating and hot-water supply apparatus performs a heating operation by heating a heating medium with a heater and circulating the heating medium through a heating terminal, a hot-water supply operation by circulating the common heating medium through a hot-water supply heat exchanger, heating service water through heat exchange with the heating medium, and supplying hot water, and a simultaneous operation of the heating operation and the hot-water supply operation, and controls a distribution ratio of the heating medium between the heating terminal and the hot-water supply heat exchanger. The apparatus determines whether the heating terminal proceeding in the heating operation is a suspendible terminal to suspend the heating operation or an unsuspendible terminal not to suspend the heating operation in response to a request for the hot-water supply operation.

Abstract: The exhaust duct includes an exhaust collecting portion connected a heat exchanger and an exhaust guiding portion communicating with the exhaust collecting portion and extended upward in a state close to a side of a cylindrical body of the heat exchanger. The exhaust collecting portion includes a connection opening constituting an inner peripheral wall, into which a cylindrical outlet side connection portion at the lower end of the heat exchanger is fitted, and a groove provided on an outer peripheral side than the inner peripheral wall of the connection opening. The packing includes a seal portion sandwiched in a compressed state between the inner peripheral wall of the connection opening in the exhaust collecting portion and an outer peripheral wall of the cylindrical outlet side connection portion in the heat exchanger to constitute a seal and an anchor portion inserted into the groove of the exhaust collecting portion.

Abstract: A heat source device comprising: a combustion chamber (2) provided between a burner (31) and a heat exchanger (1); an inlet pipe (20) for allowing a fluid to be heated to flow in the heat exchanger (1); an outlet pipe (21) for allowing the fluid to be heated to flow out from the heat exchanger (1); and a winding pipe (27) wound around an outer surface of a peripheral wall of the combustion chamber (2), wherein either the inlet pipe (20) or the outlet pipe (21) has an orifice (91) for throttling a fluid flow path of the fluid to be heated flowing in the inlet pipe (20) or the outlet pipe (21).

Abstract: The heat exchanger (1) has a plurality of heat exchange units (10) stacked in a direction of a gas flow passage of combustion exhaust gas, each of the heat exchange units (10) includes an internal space (14) through which a fluid to be heated flows, a plurality of gas vents (13) penetrating the internal space (14) in a non-communicating state and through which the combustion exhaust gas passes, and an inwardly directed step portion (17) reducing a height of the internal space (14) between adjacent gas vents (13).

Abstract: A rotational shaft is placed through insertion holes of rubber washers sandwiching a portion of an impeller having a mount hole. The impeller is mounted on the rotational shaft with a nut on a threaded distal end portion of the rotational shaft. The rotational shaft of the motor includes a locking surface. The insertion holes of the rubber washers each have the same shape as the cross-sectional shape of the rotational shaft. The mount hole of the impeller includes a spacing portion extending at an angle from the linear portion of the insertion hole of each rubber washer away from the locking surface of the rotational shaft. Although the impeller rotates with respect to the rotational shaft under a frictional force applied from the nut tightened against the rotational shaft, this structure prevents metallic contact between the impeller at the mount hole and the locking surface of the rotational shaft.

Abstract: A method of controlling a premixing apparatus that mixes fuel gas with air and supplies thus obtained air-fuel mixture, through a fan to a burner, includes at a time of changing over to a small-capacity state in which a first ventilation resistance in an air supply passage is increased and also in which a second ventilation resistance in a gas supply passage is increased, rotating a butterfly valve down to a closing side stop angle; and at a time of changing over to a large-capacity state in which the first ventilation resistance in the air supply passage is decreased and also in which the second ventilation resistance in the gas supply passage is decreased, rotating the butterfly valve up to an open-side stop angle.

Abstract: A combustion apparatus (1) has a burner (11) configured to burn combustion gas, a heat exchanger (12) disposed below the burner (11), and a combustion fan (13) configured to supply air for combustion, wherein the combustion apparatus performs post-purge operation in which the combustion fan (13) is activated for a predetermined period of time after combustion operation of the burner (11) stops, and intermittent blower operation in which activation and deactivation of the combustion fan (13) is repeated a plurality of times at predetermined intervals after the post-purge operation ends.

Abstract: A hot-water supply apparatus capable of restraining the occurrence of noises from a building wall surface side includes a hot-water supply apparatus main body having a burner and a heat exchanger that generates hot water by combustion exhaust of the burner, and a rectangular parallelepiped main body case that houses the hot-water supply apparatus main body. A back plate (5c), which closes the back side of the main body case, is installed to a building wall surface (W) such that the back plate (5c) opposes the building wall surface (W) with a predetermined void space (S) provided therebetween. A soundproof member (18), which closes at least a part of an open end of the void space (S), is provided on the main body case (5).

Abstract: [Problems] A flat burner elongated in the longitudinal direction has, at an upper end thereof, a main burner port (63) and a flame retention port (64) positioned at least on laterally one side of the main burner port (63). The flat burner uses hydrogen-containing fuel as a fuel. Flash back is prevented at the flame retention port in which the gas ejection speed becomes relatively small. [Solving Means] A lean fuel-air mixture which is leaner in fuel concentration than a theoretical fuel-air ratio is ejected from the main burner port (63) and a gas containing only fuel is ejected from the flame retention port (64). In addition, the height, on the side of the main burner port (63), of the upper end of the flame retention port (64), is made lower than the height of the upper end of the main burner port (63).

Abstract: A heat exchanger includes a plurality of heat exchange units. Each of the plurality of heat exchange units includes: an internal space in which a fluid to be heated flows, a plurality of gas vents penetrating the internal space in a non-communicating state and through which combustion exhaust gas flows, at least one inlet port, and at least one outlet port. At least the one inlet port and at least the one outlet port in each of the heat exchange units are disposed at both ends in a longitudinal direction of the heat exchange unit and are shifted (offset) in a lateral direction of the heat exchange unit.

Abstract: A fixing plate for the thermal insulation material is attached to the combustion plate flange part. Provided that a direction leaving away from the air-fuel mixture ejection part of the combustion plate is defined as an outward side direction, there are disposed: on the side edge in the outward side direction of the fixing plate, bent edge parts, which come into contact with the side edge in the outward side direction of the thermal insulation materials; and a plurality of tongue-shaped pressing claws which are elongated from the bent edge part so as to press and prevent the thermal insulation materials from getting released away from the fixing plate.

Abstract: A premixing apparatus for mixing air with a fuel gas in order to supply a burner with an air-fuel mixture through a fan, wherein a downstream end of a gas supply passage is connected to a gas suction part disposed in a portion, on an upstream side of the fan, of an air supply passage. The gas supply passage has interposed therein a zero governor for adjusting a secondary gas pressure to an atmospheric pressure. Even if the calorific value of the fuel gas may fluctuate, excess air ratio of the air-fuel mixture is arranged to be maintained at a constant value. The premixing apparatus is provided with: an excess air ratio detection device for detecting an excess air ratio of the air-fuel mixture; and a flow control valve interposed in a portion, on a downstream side of the zero governor, of the gas supply passage. The flow control valve is controlled such that the excess air ratio of the air-fuel mixture detected by the excess air ratio detection device becomes constant.

Abstract: A blower fan including an impeller easily mounted on the rotational shaft of a motor generates less noise. The impeller is mounted on the rotational shaft of the motor using a fastener with an elastic vibration isolator and a washer in between. The washer has a predetermined shape including radial projections from a circumference about a central receiving hole. The vibration isolator has the predetermined shape larger than the predetermined shape of the washer, and has a first recess having the predetermined shape on its top surface to receive the washer fittingly. The impeller has a second recess having the predetermined shape on its top surface to receive the vibration isolator fittingly. The vibration isolator thus separates the impeller mounted on the rotational shaft from the washer in both the axial and rotational directions of the motor to reduce vibrations in both directions propagating to the impeller, generating less noise.

Abstract: A heat exchanger disposed on a downstream side of a gas flow passage of combustion exhaust gas ejected from a burner comprising a plurality of heat exchange units stacked in a gas flow passage direction of the combustion exhaust gas, an inlet pipe, and an outlet pipe, wherein the inlet pipe and the outlet pipe are provided so as to protrude from a most downstream heat exchange unit located on a most downstream side of the gas flow passage of the combustion exhaust gas toward the downstream side of the gas flow passage of the combustion exhaust gas.

Abstract: An electrically operated gas flow regulating valve causes a needle valve body to move axially by the rotation of an electric motor through a motion conversion mechanism. The mechanism includes: a rotating body rotated by the electric motor; a cylindrical cam body prevented from rotating; a cam pin which is engaged with a spiral cam groove formed in the cam body and which is fixed to the needle valve body. The cam body is divided into two parts of a forward-side half part and backward-side half part with the cam groove serving as a boundary. The backward-side half part is urged by a coil spring in the forward direction such that the cam pin is pinched between the forward-side side edge of cam groove formed in the forward-side half part and the backward-side side edge of cam groove formed in the backward-side half part, thereby restraining the occurrence of hysteresis.

Abstract: A totally aerated combustion burner has: a burner body which is supplied therein with air-fuel mixture; and a combustion plate part which covers an open surface of the burner body. The combustion plate part is constituted by: a burner frame in a shape of a picture frame; a metal-fiber knit which is disposed to cover, from a burner-body side, an opening enclosed by the burner frame; and a distribution plate which has formed therein a multiplicity of distribution holes and which sandwiches the metal-fiber knit between the burner frame and the distribution plate. Only the metal-fiber knit is spot-welded to that opening peripheral part of the burner frame which is positioned on a same surface as the opening. The distribution plate is spot-welded to that portion of the burner frame which is offset from the opening peripheral part toward the burner-body side.