Abstract: There is provided a heat exchanger and a water heater having the heat exchanger including a uniform thickness of tin plating layer on the inner surface of a water feeding pipe. The heat exchanger H includes copper pipes 8 and 10 disposed in a casing 1 as a water feeding pipe 4 and a turbulent flow generator 13 disposed in the copper pipes 8 and 10. The turbulent flow generator 13 has a copper plating layer 14 on the surface portion thereof. The tin plating layers 17 and 18 are disposed on the inner surface of the copper pipes 8 and 10 and the surface of the turbulent flow generator 13.

Abstract: A solenoid valve control device is provided with: a first relay connected in series to a drive coil of a solenoid valve between output terminals of a rectifier circuit; a photocoupler configured to output a voltage of a GND level when a current equal to or greater than a predetermined level is flowing in a contact in the first relay and output a voltage of a V5 level when the current equal to or greater than a predetermined level does not flow in the contact in the first relay; and an integration circuit configured to smooth an output voltage Va1 from the photocoupler. When an output voltage from the integration circuit is not greater than a first threshold value, a microcomputer detects that the first relay is in an on state.

Abstract: A combustion device has tubular burners with mixing tubes made by joining together two plate members which have formed therein half-split mixing tubes at a distance from one another and which, when joined together, form a clearance serving as a carryover flame hole to communicate a mixing tube with an adjoining mixing tube. An intermediate flame hole portion is formed by recessing backward the front end of the carryover flame hole. A cover portion is formed in each of the two plate members so as to lie opposite to each other with a recessed space lying therebetween. The recessed space is defined as a space that is generated between the intermediate flame hole portion and a line that is drawn in front of the intermediate flame hole portion along the same longitudinal direction as the front end, except for the part of the intermediate flame hole portion.

Abstract: A totally aerated combustion burner having a combustion plate with a multiplicity of flame holes includes a distribution chamber, a mixing chamber, and an air supply chamber. The mixing chamber has a front surface with a plurality of nozzle holes disposed in parallel with, and at a lateral distance from, one another so that a fuel gas to be ejected from the nozzle holes and the primary air from the air supply chamber get mixed in the mixing chamber. A wall plate is disposed upright on a bottom surface of the mixing chamber in a manner to lie opposite to the front surface of the mixing chamber while leaving a ventilation clearance to the front surface. An air inlet is formed in such a portion at the bottom surface of the mixing chamber as to face the ventilation clearance.

Abstract: Each of the water heaters 1 performs a master and slave setting process that transmits prescribed response data to the other water heaters 1 via a communication line 8 at a timing according to its own identification number and different from those of the other water heaters in a prescribed master and slave setting time period, that sets the water heater itself to slave in a case of receiving the response data from another water heater 1 assigned with an identification number having a priority higher than its own identification number in the master and slave setting time period, and that sets the water heater itself to master in a case of not receiving the response data from another water heater assigned with an identification number having a priority higher than its own identification number in the master and slave setting time period.

Abstract: A hot-water supply system includes a switching valve (35) which has a bypass circuit which bypasses the water softening device (30) by directly connecting the water supply pipe (P1) and the inlet pipe (P3) of a hot-water supply device to each other, and a control unit (50). The control unit (50) includes a switching valve drive circuit which switches the switching valve (35) to the mode in which water is supplied from the water supply pipe (P1) to the hot-water supply device (1) via the bypass circuit, based on the determination of the timing of salt replenishment, and a display drive circuit which displays intention, in which salt replenishment is needed, on a display portion (51) of a remote controller (RC).

Abstract: A combustion plate for use in a totally aerated combustion burner has a ceramic plate body with a multiplicity of flame holes formed therein for ejecting a premixed gas. The plate body is provided, in a lattice shape, with non-flame-hole portions having no flame holes therein. Each of such regions of the plate body as are enclosed by the non-flame-hole portions constitutes a collective flame-hole portion having formed therein a plurality of flame holes. It is so arranged that flame lifting can be effectively prevented in the flame holes on the periphery of the collective flame-hole portions. Along each of such sides of the non-flame-hole portions as are adjacent to each of the collective flame-hole portions, outside flame holes are formed at a predetermined spacing therebetween in a longitudinal direction of the non-flame-hole portions. This predetermined spacing is greater than a spacing, in the longitudinal direction of the non-flame-hole portion.

Abstract: A storage type water heater comprising: a stored hot water tank; a heating unit including a heat exchanger, a gas burner, and an air supply fan; a circulation pipe line; a circulating pump; a first temperature sensor for detecting an inlet side temperature T1; a second temperature sensor for detecting an outlet side temperature T2; and a controller including a control arrangement which actuates the circulating pump to circulate the stored hot water inside of the circulation pipe line when the heating unit is in a non-operated state, and determines an abnormality in one of the first temperature sensor and the second temperature sensor based on a temperature difference (|T1?T2|).

Abstract: A latent heat exchanger (1) has a casing (2), a heat-absorbing tube (50) accommodated in the casing (2), an inlet header (60), and an outlet header (70). The casing (2) has a casing main body (10) and a top plate (40) closing an upper opening (16) of the casing main body (10). The back wall (11), the front wall (12), the bottom wall (13), one side wall (14), and the other side wall (15) of the casing main body (10) are formed integrally by draw-processing a single metal plate.

Abstract: A forced flue type combustion device in which an orifice is provided in at least one of an air supply passage and an exhaust passage, and in which the existence/nonexistence of a clog is determined on the basis of a detected pressure difference between the pressures on the upstream and downstream sides of the orifice, is arranged so that the existence/nonexistence of a clog can be determined with accuracy even during weak combustion with a low rotational speed of the combustion fan. Processing for increasing the rotational speed of the combustion fan is intermittently executed during weak combustion. During weak combustion, clogging determination processing based on the detected pressure difference value is executed only when the rotational speed of the combustion fan is increased. Clogging determination processing is started after the rotational speed of the combustion fan has become stable.

Abstract: A drain pipe 54 includes an upper end portion 54a which is connected to a concave 38a of a leading end 38 of an exhaust tube 34, and a lower end portion 54b which is opened to the inside of a warm air furnace below the concave 38a. The lower end portion 54b is formed as a tubular portion where a membrane is formed at a plane orthogonal to an axis line 54d by a surface tension of a drain. A leading end 54e of the tubular portion is formed as an opening 54f with an area large enough such that the membrane is not generated by the surface tension of the drain.

Abstract: In a hot-water storage type heating unit 1, a liquid-liquid heat exchanger 15, which exchanges heat between a first hot-water circulation circuit 12 through which hot water stored in a hot-water storage tank 11 circulates and a heating circulation circuit 14 in which the hot water flows from a radiator unit 3 for heating, is disposed above the hot-water storage tank 11, and a circulation pump 16 is disposed in the first hot-water circulation circuit 12 on the downstream side of the liquid-liquid heat exchanger 15. In order to return the gas, which is separated by a gas-liquid separator 17 provided so as to be interposed in the first hot-water circulation circuit 12 between the liquid-liquid heat exchanger 15 and the circulation pump 16, to the hot-water storage tank 11, a return passage 18 which communicates between the hot-water storage tank 11 and the gas-liquid separator 17 is provided.

Abstract: A vent hole 12 is provided in the upper part of a front panel 1e of an outer case 1. Air in a room having passed through a section in which a main heat exchanger 6 is arranged is led to the vent hole 12 through a space between an upper plate 1b of an outer case 1 and an upper wall 2d of a combustion housing 2. A drain dish 18 is arranged on the upper face of the upper wall 2d of the combustion housing 2.

Abstract: A hot-water supply system includes a switching valve (35) which has a bypass circuit which bypasses the water softening device (30) by directly connecting the water supply pipe (P1) and the inlet pipe (P3) of a hot-water supply device to each other, and a control unit (50). The control unit (50) includes a switching valve drive circuit which switches the switching valve (35) to the mode in which water is supplied from the water supply pipe (P1) to the hot-water supply device (1) via the bypass circuit, based on the determination of the timing of salt replenishment, and a display drive circuit which displays intention, in which salt replenishment is needed, on a display portion (51) of a remote controller (RC).

Abstract: The room heater has, in an outer case 1, both a first air flow passage that leads to a vent hole 12 through a section in which the main heat exchanger 6 is arranged and a second air flow passage that does not pass through the section in which the main heat exchanger 6 is arranged but leads to the vent hole 12 through a section in which a supplementary heat exchanger 6? is arranged provided. At least one of the first damper 20 which can freely block the first air flow passage and the second damper 21 which can freely block the second air flow passage is provided, and the first air flow passage or the second air flow passage is blocked in a weak combustion period.

Abstract: A combustion apparatus has a burner, a combustion box containing therein a heat exchanger, an exhaust passage in fluid communication with the combustion box, a fan for supplying the burner with combustion air, and a predetermined length of air suction duct in fluid communication with a suction opening formed in a fan casing. The air suction duct has: on a downstream end thereof, an outlet cylindrical portion which is smaller in diameter than a diameter of the suction opening in the fan casing and which lies opposite to the suction opening; and a flange portion which overhangs radially outward from a perimeter of the air suction duct adjacent to the outlet cylindrical portion into contact with that peripheral portion of the fan casing which forms the suction opening. The flange portion is provided with an auxiliary suction opening in fluid communication with a space surrounding the outlet cylindrical portion.

Abstract: Provided are a heat exchanger that does not impede downsizing and removes water in the heat absorbing pipe adequately with a simple configuration even when the reduction in diameter of the heat absorbing pipe is made. A heat exchanger 5 in which heat absorbing pipes 51 are disposed in a multi-tier arrangement within a casing 50 which is the passage of combustion exhaust gas, both pipe ends 511,512 of each of the heat absorbing pipes 51 are connected respectively to two headers 54, 55 provided on a side plate 52 of the casing 50, and water introduced from an external pipe 63 to each of the heat absorbing pipes 51 through the header 54 is heat-exchanged and heated by combustion exhaust gas. The pipe ends 511, 512 of the heat absorbing pipes 51 are arranged at a predetermined vertical interval.

Abstract: A hot water supply apparatus including: a hot-water supply pipe for guiding hot water generated by a hot-water generator to a hot-water supplying terminal; two hot-water supply temperature sensors for detecting water temperature in the hot-water supply pipe; a temperature control unit for adjusting a temperature of the hot water supplied to the hot-water supplying terminal; a sensor abnormality determining unit for determining sensor abnormality when a difference between temperatures detected by the two hot-water supply temperature sensors is larger than a predetermined permissible error; a sensor selector for selectively setting one hot-water supply temperature sensor detecting a higher temperature as a hot-water supply temperature sensor for temperature control; and a hot-water supply temperature controller for controlling the temperature control unit so that a temperature detected by the hot-water supply temperature sensor for temperature control selected from the two hot-water supply temperature sensors i