Hot water supply heater

Abstract

To provide a technique for facilitating more accurate detection of occurrence of clogging when clogging occurs between fins in a hot water supply heater having a configuration in which the fins are provided in a heat exchanger supplied with exhaust gas from a burner.SOLUTION: In a hot water supply heater 1, an abnormality detection section determines an abnormality depending on whether or not an electric current applied to a driving source is in a predetermined electric current rise state when a first burner is in a combustion state in a hot water supply combustion chamber 5A. In the case where the first burner is in a non-combustion state in the hot water supply combustion chamber 5A and a second burner nearest to a partition member 80 in a heating combustion chamber 6A is in a combustion state, the abnormality detection section determines an abnormality depending on whether or not a temperature detected by a temperature sensor 82 is in a predetermined temperature rise state.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a water heater.

Background Art

[0002] Patent Document 1 discloses an example of a combustion device configured as a gas appliance. In the combustion device of Patent Document 1, a burner is disposed below the device body, a heat exchanger is disposed above the burner, and the heat exchanger is configured to be heated by the combustion of the burner. Then, air required for the combustion of the burner and air required for cooling the device body are supplied into the device body by a fan. A temperature detection means for detecting the temperature of the combustion gas of the burner is provided in the device body. The temperature detection means includes a heat-sensitive rod inserted into the device body and a heat-sensitive element attached to the root portion of the heat-sensitive rod. The combustion device detects clogging between a plurality of fins provided in the heat exchanger based on the temperature detected by the temperature detection means.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The combustion device of Patent Document 1 is provided with a partition member that divides the interior of the device body into a first accommodation space that houses a first burner and a first heat exchanger, and a second accommodation space that houses a second burner and a second heat exchanger. And the combustion fan supplies air necessary for the combustion of the first burner and the second burner and air necessary for cooling the surface of the partition member to the first accommodation space and the second accommodation space. And a heat-sensitive rod with a heat-sensitive element attached to its base is inserted inside the partition member. In a configuration like this, when clogging occurs between the fins provided in the heat exchanger, the air in the accommodation space is insufficient compared to the case where there is no clogging, so the flame extends upward seeking air. Because of such a characteristic, it is possible to determine whether or not the fins are clogged by determining whether or not the temperature detected by the temperature detection means is on an upward trend.

[0005] However, the determination method as in Patent Document 1 has a problem that it is difficult to accurately detect clogging when the burner close to the partition member is in a non-combustion state. When the burner close to the partition member is in a non-combustion state, even if clogging occurs in the fins and the flame extends, the extended flame is likely to be far from the temperature detection means, and it is difficult for the vicinity of the temperature detection means to rapidly increase in temperature.

[0006] One of the objects of the present disclosure is to provide a technology that can more accurately detect the occurrence of clogging when clogging occurs between fins in a hot water heater with a configuration in which fins are provided in a heat exchanger to which exhaust gas from a burner is supplied.

Means for Solving the Problems

[0007] A hot water heater which is one of the present disclosures is equipped with a first burner that burns gas and a first heat exchanger that is heated by the exhaust gas generated by the first burner, and a hot water supply circuit that heats water supplied from the outside by the first heat exchanger to supply hot water. A second burner that burns gas, a second heat exchanger heated by the exhaust generated by the second burner, and a heat medium circulation path that is a path for circulating the heat medium through the second heat exchanger. The heat medium is heated by the second heat exchanger, and a heating circuit that supplies the heat medium to a heating terminal via the heat medium circulation path. A housing that houses the first burner, the second burner, the first heat exchanger, and the second heat exchanger. A partition member that partitions the inside of the housing. A fan that supplies air into the housing. A fan control device that controls the fan. A temperature sensor provided on the partition member. An abnormality detection unit that detects an abnormality in the gas flow inside the housing. Comprising. Inside the housing, a hot water combustion chamber that houses the first burner and the first heat exchanger and a heating combustion chamber that houses the second burner and the second heat exchanger are partitioned by the partition member. The entire area where the first burner is arranged in the hot water combustion chamber is divided into a plurality of burner blocks, and the entire area where the second burner is arranged in the heating combustion chamber is divided into a plurality of burner blocks. The temperature sensor is arranged to detect the temperature of the heating combustion chamber. A plurality of fins are provided on the first heat exchanger and the second heat exchanger. The fan has a rotating body and a drive source that rotates the rotating body, and has a configuration in which the rotation speed of the rotating body increases as the current applied to the drive source increases. The fan control device controls the rotation speed of the rotating body by increasing or decreasing the current applied to the drive source. The abnormality detection unit When any one of the burner blocks is in a combustion state in the hot water combustion chamber, the abnormality is determined based on whether the current applied to the drive source is in a predetermined current rising state. In the hot water combustion chamber, none of the burner blocks is in a combustion state. When the burner block closest to the partition member in the heating combustion chamber is in a combustion state, the abnormality is determined based on whether the temperature detected by the temperature sensor is in a predetermined temperature rise state.

Advantages of the Invention

[0008] According to the technology related to the present disclosure, regarding a hot water heater having a configuration in which fins are provided on a heat exchanger to which exhaust gas from a burner is supplied, when clogging occurs between the fins, it is easier to more accurately detect the occurrence of clogging.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Modes for Carrying Out the Invention

[0010] Each of the following [1] to [2] is an example of a hot water heater included in the present disclosure.

[0011] 〔1〕A first burner that burns gas, a first heat exchanger heated by the exhaust gas generated by the first burner, a hot water supply circuit that heats water supplied from the outside by the first heat exchanger to supply hot water, A second burner that burns gas, a second heat exchanger heated by the exhaust gas generated by the second burner, and a heat medium circulation path that is a path through which the heat medium circulates through the second heat exchanger, a heating circuit that heats the heat medium by the second heat exchanger and supplies the heat medium to a heating terminal via the heat medium circulation path, A housing that houses the first burner, the second burner, the first heat exchanger, and the second heat exchanger, A partition member that partitions the interior of the housing, A fan that supplies air into the housing, A fan control device that controls the fan, A temperature sensor provided on the partition member, An abnormality detection unit that detects an abnormality in the flow of gas in the housing, and comprising Inside the housing, a hot water combustion chamber that houses the first burner and the first heat exchanger and a heating combustion chamber that houses the second burner and the second heat exchanger are partitioned by the partition member, The entire area where the first burner is arranged in the hot water combustion chamber is divided into a plurality of burner blocks, and the entire area where the second burner is arranged in the heating combustion chamber is divided into a plurality of burner blocks, The temperature sensor is arranged to detect the temperature of the heating combustion chamber, A plurality of fins are provided on the first heat exchanger and the second heat exchanger, The fan has a rotating body and a drive source that rotates the rotating body, and is configured such that the higher the current applied to the drive source, the higher the rotational speed of the rotating body, The fan control device controls the rotational speed of the rotating body by increasing or decreasing the current applied to the drive source, The abnormality detection unit When any one of the burner blocks in the hot water combustion chamber is in a combustion state, the abnormality is determined based on whether the current applied to the drive source is in a predetermined current increasing state, When all of the burner blocks in the hot water combustion chamber are in a non-combustion state and the burner block closest to the partition member in the heating combustion chamber is in a combustion state, the abnormality is determined based on whether the temperature detected by the temperature sensor is in a predetermined temperature increasing state A hot water and heating machine.

[0012] In the water heater and space heater described in [1] above, if clogging occurs between the fins in the water heating combustion chamber, the flow of the gas in the water heating combustion chamber trying to escape upward is obstructed, and the torque for rotating the rotating body of the fan increases. Therefore, in order to rotate the rotating body at the same rotational speed, the current supplied to the drive source increases. The water heater and space heater utilizes such a change to determine whether an abnormal clogging has occurred between the fins in the water heating combustion chamber by determining whether the current applied to the drive source is in a predetermined current increase state during combustion in the water heating combustion chamber, enabling a more accurate determination.

[0013] On the other hand, in the water heater and space heater described in [1] above, when the burner block in the water heating combustion chamber is in a non-combustion state, that is, when the first burner is in a non-combustion state, the temperature detected by the temperature sensor is utilized to determine whether an abnormal clogging has occurred between the fins in the space heating combustion chamber. When determining an abnormality on the space heating combustion chamber side in this way, when the first burner in the water heating combustion chamber is in a non-combustion state and the burner block closest to the partition member in the space heating combustion chamber is in a combustion state, the abnormality is determined based on whether the temperature detected by the temperature sensor is in a predetermined temperature increase state. The case where the burner block closest to the partition member in the space heating combustion chamber is in a combustion state means that the temperature sensor provided on the partition member (the sensor for detecting the temperature of the space heating combustion chamber) is likely to be affected by the combustion of the second burner. That is, when the upward extension of the flame occurs due to clogging between the fins in the space heating combustion chamber, the detected temperature of the temperature sensor is likely to increase. In such a case, if the abnormality is determined based on whether the temperature detected by the temperature sensor is in a predetermined temperature increase state, it is possible to more accurately determine whether an abnormal clogging has occurred between the fins in the space heating combustion chamber.

[0014] 〔2〕If in the hot water combustion chamber, none of the burner blocks is in a combustion state, and in the heating combustion chamber, the burner block closest to the partition member is in a non-combustion state and the burner block farther from the partition member than the burner block closest to the partition member is in a combustion state, the abnormality detection is not performed. 〔1〕A hot water and heating machine.

[0015] In the hot water and heating machine of 〔2〕, when the burner block in the hot water combustion chamber is in a non-combustion state, the burner block closest to the partition member in the heating combustion chamber is in a non-combustion state, and the second burner farther from the partition member than the closest burner block is in a combustion state, it is the case during the combustion of only the heating combustion chamber among the hot water combustion chamber and the heating combustion chamber, and when the temperature sensor provided on the partition member is hardly affected by the combustion of the second burner. If the abnormality detection is not performed in such a case, it is possible to prevent an erroneous determination of an abnormality caused by the fact that the influence of the combustion of the second burner hardly reaches the temperature sensor.

[0016] <First Embodiment> The following description relates to the hot water and heating machine 1 according to the first embodiment. 1. Overall configuration of the hot water and heating machine 1 FIG. 1 is a schematic circuit diagram of the hot water and heating machine 1. The hot water and heating machine 1 mainly includes a hot water circuit 2, a heating circuit 3, a bath circuit 4, etc., and is a device capable of performing hot water supply operations, automatic water filling operations, supplementary heating operations, heating operations, etc.

[0017] The hot water and heating unit 1 has a housing (not shown), and in this housing, a container 1A configured as a metal casing is provided. Inside this container 1A, a first combustion system part 5 and a second combustion system part 6 are configured. The container 1A is configured, for example, as a metal can body or as a metal box body, and is configured to accommodate a hot water burner 8A (first burner), a heating burner 33A (second burner), a hot water side heat exchanger 7 (first heat exchanger), a heating side heat exchanger 32 (second heat exchanger), etc., which will be described later. The first combustion system part 5 is a combustion system that performs gas combustion and water heating when the hot water circuit 2 performs a hot water supply operation. The second combustion system part 6 is a combustion system that performs gas combustion and water heating during a heating operation or a supplementary heating operation.

[0018] The hot water circuit 2 is a circuit that heats the water supplied from outside the hot water and heating unit 1 by the hot water side heat exchanger 7 and supplies hot water. The hot water circuit 2 includes the first combustion system part 5, and specifically includes a plurality of hot water burners 8A and the hot water side heat exchanger 7. In the first combustion system part 5, a hot water combustion chamber 5A is provided, and a hot water side burner unit 8 and the hot water side heat exchanger 7 are provided in the hot water combustion chamber 5A.

[0019] The hot water side burner unit 8 includes burner blocks 9A, 9B, 9C, and each of the burner blocks 9A, 9B, 9C includes a plurality of hot water burners 8A. Each of the plurality of hot water burners 8A corresponds to an example of the first burner and is configured as a gas burner that burns gas. In the hot water combustion chamber 5A, the entire area where the hot water burner 8A (first burner) is arranged is divided into a plurality of burner blocks 9A, 9B, 9C.

[0020] The hot water supply side heat exchanger 7 corresponds to an example of the first heat exchanger and is a heat exchanger heated by the exhaust gas generated by the hot water supply burner 8A (first burner). The hot water supply side heat exchanger 7 includes a hot water supply side first heat exchanger 7A and a hot water supply side second heat exchanger 7B. In the first combustion system section 5, the hot water supply side first heat exchanger 7A is provided above a plurality of hot water supply burners 8A, and the hot water supply side second heat exchanger 7B is provided above the hot water supply side first heat exchanger 7A. A pipe line 7C is connected between the downstream end of the hot water supply side second heat exchanger 7B and the upstream end of the hot water supply side first heat exchanger 7A, and the hot water flowing through the hot water supply side second heat exchanger 7B flows through the pipe line 7C to the hot water supply side first heat exchanger 7A. The hot water supply side heat exchanger 7 heats the water passing through its interior by the exhaust gas (combustion exhaust gas) generated by burning gas with a plurality of hot water supply burners 8A. The hot water supply side first heat exchanger 7A recovers sensible heat from the combustion exhaust gas discharged from the hot water supply side burner unit 8, and the hot water supply side second heat exchanger 7B recovers latent heat from the combustion exhaust gas discharged from the hot water supply side burner unit 8.

[0021] The hot water supply circuit 2 further includes a water supply pipe 11, a control valve 13A, a water volume sensor 14, a hot water outlet pipe 10, a bypass pipe 12, a control valve 13B, a thermistor 15A (hot water supply inner cylinder thermistor), a thermistor 15B (hot water supply and outlet thermistor), etc. The water supply pipe 11 is connected to the inlet of the hot water supply side heat exchanger 7. The water supply pipe 11 is connected to an external pipe, and is configured as a pipe line that introduces tap water from, for example, a water supply and flows this tap water toward the upstream end (inlet) of the hot water supply side heat exchanger 7. The water volume sensor 14 is a sensor that detects the flow rate of the water flowing through the water supply pipe 11. The control valve 13A is a valve for controlling the flow rate of the water flowing through the water supply pipe 11, and is a valve that changes the opening degree of the water supply pipe 11 under the control from the outside (specifically, the control by the control device 70). The hot water outlet pipe 10 is connected to the downstream end (outlet) of the hot water supply side heat exchanger 7. The hot water outlet pipe 10 is a pipe line that flows the hot water heated by the hot water supply side heat exchanger 7. The hot water outlet pipe 10 forms a path for discharging the hot water heated by the hot water supply side heat exchanger 7 outside the appliance.

[0022] A bypass pipe 12 is connected between the water supply pipe 11 and the hot water outlet pipe 10 so as to bypass the hot water side heat exchanger 7. A control valve 13B (bypass control valve) is provided in the bypass pipe 12. The control valve 13B is a valve for controlling the flow rate of water flowing through the bypass pipe 12. Specifically, it is configured as a valve that changes the opening degree of the bypass pipe 12 in response to external control (specifically, control by the control device 70).

[0023] A thermistor 15A is provided upstream of the connection portion of the bypass pipe 12 in the hot water outlet pipe 10. The thermistor 15A detects the temperature of the hot water discharged from the hot water side heat exchanger 7. Specifically, it detects the hot water temperature near the outlet of the first hot water side heat exchanger 7A. A thermistor 15B is provided downstream of the connection portion of the bypass pipe 12 in the hot water outlet pipe 10. The thermistor 15B detects the hot water temperature after the water from the bypass pipe 12 is mixed. Specifically, it detects the temperature of the hot water supplied downstream of the confluence point of the bypass pipe 12 in the hot water outlet pipe 10. The temperatures of the hot water detected by these thermistors 15A and 15B are input to the control device 70 described later.

[0024] The hot water supply circuit 2 further includes a gas pipe 16, a main gas solenoid valve 17, a gas proportional valve 18, and a switching valve 19. The gas pipe 16 is a pipe through which gas supplied from outside the hot water supply and heating unit 1 via the gas inlet passes, and forms a path for supplying gas to the hot water supply burner 8A. The main gas solenoid valve 17 is provided on the upstream side of the gas pipe 16, and the gas proportional valve 18 is provided on the downstream side of the main gas solenoid valve 17. In the gas pipe 16, the downstream side of the gas proportional valve 18 (hot water supply gas proportional valve) branches, and branch pipes 16A to each of the burner blocks 9A, 9B, 9C and branch pipes 16B to each of the burner blocks 34A, 34B are provided. Each branch pipe 16A is provided with a switching valve 19 configured as a solenoid valve. The switching valve 19 (hot water supply switching solenoid valve) switches the branch pipe 16A between an open state (supply possible state) and a closed state (shut-off state), and the supply and shut-off of fuel gas to each of the burner blocks 9A, 9B, 9C are individually switched by each switching valve 19. By switching the switching valve 19, the combustion range of the hot water supply side burner unit 8 is switched, and each combustion range is associated as a stage number.

[0025] The hot water supply circuit 2 further includes a fan 20. The fan 20 is provided below the hot water supply combustion chamber 5A, and by the operation of the fan 20, combustion air is supplied to each hot water supply burner 8A and the heating burner 33A, and the combustion exhaust gas discharged from the hot water supply side burner unit 8 and the heating side burner unit 33 is discharged from the exhaust port. The hot water supply circuit 2 is also provided with an igniter for ignition, an ignition electrode, a hot water supply flame rod, and the like.

[0026] The bath circuit 4 includes a bath circulation path 63 and a bath heat exchanger 50. The bath circulation path 63 forms a flow path configured to circulate the hot water derived from the external bathtub 52 and introduce it into the bathtub 52. The bath heat exchanger 50 is configured as a liquid-liquid heat exchanger that performs heat exchange between the heat medium flowing through the bath heating pipe 51 and the hot water flowing through the bath circulation path 63.

[0027] The bathtub heat exchanger 50 is provided with a pipe 50A that forms part of the bathtub circulation path 63, and is configured such that the bathtub heating pipe 51 is disposed within the pipe 50A. The bathtub circulation path 63 includes the pipe 50A, the bathtub supply pipe 53, and the bathtub return pipe 54. When the bathtub circulation pump 55 operates, the bathtub circulation path 63 functions as a flow path for drawing out hot water from the bathtub 52 provided outside the water heater and warmer 1, and also functions as a flow path for circulating the drawn-out hot water and introducing it into the bathtub 52. The bathtub return pipe 54 is provided with a bathtub circulation pump 55 for flowing the hot water in the bathtub return pipe 54 in a predetermined direction, and a water flow switch 57 for detecting that hot water having a predetermined flow rate or more is flowing through the bathtub return pipe 54. The bathtub return pipe 54 is provided between the bathtub 52 outside the appliance and the pipe 50A, and forms a flow path for flowing hot water from the bathtub 52 to the pipe 50A when the bathtub circulation pump 55 operates. The bathtub supply pipe 53 is provided between the pipe 50A and the bathtub 52, and forms a flow path for flowing hot water from the pipe 50A to the bathtub 52 when the bathtub circulation pump 55 operates. The bathtub supply pipe 53 is provided with a bathtub supply thermistor 64 for detecting the temperature of the hot water flowing out from the bathtub heat exchanger 50 to the bathtub 52. The bathtub return pipe 54 is provided with a bathtub return thermistor 65 for detecting the temperature of the hot water flowing into the bathtub return pipe 54 from the bathtub 52.

[0028] The bathtub return pipe 54 is connected to a drop pipe 59 which is branched from the hot water outlet pipe 10. The drop pipe 59 communicates with the bathtub return pipe 54. The drop pipe 59 is provided with a hot water supply solenoid valve 60, a drop water volume sensor 61, a plurality of check valves 62, etc. When the hot water supply solenoid valve 60 provided in the drop pipe 59 is opened during the operation of the hot water supply circuit 2, the hot water heated by the hot water supply circuit 2 is supplied to the bathtub 52 through the drop pipe 59.

[0029] The heating circuit 3 is a circuit that can heat a heat medium by means of a heating-side heat exchanger 32 and supply the heat medium to heating terminals via a heat medium circulation path 48. In the present embodiment, the heat medium is hot water. The heating circuit 3 includes a second combustion system unit 6 and a heat medium circulation path 48. The second combustion system unit 6 is provided with a heating combustion chamber 6A, and a heating-side burner unit 33 and a heating-side heat exchanger 32 are provided within the heating combustion chamber 6A.

[0030] The heating-side burner unit 33 includes burner blocks 34A and 34B, and each of the burner blocks 34A and 34B includes a plurality of heating burners 33A. Each of the plurality of heating burners 33A corresponds to an example of a second burner and is configured as a gas burner that burns gas. The entire area where the heating burner 33A (second burner) is arranged in the heating combustion chamber 6A is divided into a plurality of burner blocks 34A and 34B.

[0031] The heating-side heat exchanger 32 corresponds to an example of a second heat exchanger and is a heat exchanger heated by the exhaust gas generated by the heating burner 33A (second burner). Specifically, it is a device that acts to heat the heat medium passing through its interior by the combustion exhaust gas of the heating burner 33A. The heating-side heat exchanger 32 includes a heating-side first heat exchanger 32A and a heating-side second heat exchanger 32B. In the second combustion system section 6, the heating-side first heat exchanger 32A is provided above the plurality of heating burners 33A, and the heating-side second heat exchanger 32B is provided above the heating-side first heat exchanger 32A. The heating-side heat exchanger 32 heats the heat medium passing through its interior by the exhaust gas (combustion exhaust gas) generated by burning gas with the plurality of heating burners 33A. The heating-side first heat exchanger 32A recovers sensible heat from the combustion exhaust gas discharged from the heating-side burner unit 33, and the heating-side second heat exchanger 32B recovers latent heat from the combustion exhaust gas discharged from the heating-side burner unit 33.

[0032] The heat medium circulation path 48 is a path for circulating the heat medium so as to pass through the heating-side heat exchanger 32, and forms a flow path of the heat medium. The heat medium circulation path 48 includes a heating high-temperature forward pipe 38A, a heating low-temperature forward pipe 38B, and a heating return pipe 38C. When the heating terminal 39A is connected as shown in FIG. 1, the heat medium circulation path 48 is configured such that the heat medium circulates through the heating high-temperature forward pipe 38A, the heating terminal 39A, and the heating return pipe 38C. When the heating terminal 39Z is connected as shown in FIG. 1, the heat medium circulation path 48 is configured such that the heat medium circulates through the heating low-temperature forward pipe 38B, the heating terminal 39Z, and the heating return pipe 38C.

[0033] The heating circuit 3 further includes an expansion tank 36, a heating circulation pump 37, a heating high-temperature thermistor 40, and a heating low-temperature thermistor 41. A heating high-temperature forward pipe 38A is connected to the outlet of the heating-side heat exchanger 32 (specifically, the outlet of the first heating-side heat exchanger 32A). The heating high-temperature forward pipe 38A is a pipe that flows the heat medium from the heating-side heat exchanger 32 toward the heating terminal 39A. The heating high-temperature forward pipe 38A is configured to communicate with the heating terminal 39A and is connected so as to be able to flow the heat medium to the heating terminal 39A.

[0034] A heating return pipe 38C is connected to the inlet of the heating-side heat exchanger 32 (specifically, the inlet of the second heating-side heat exchanger 32B). The heating return pipe 38C is a pipe that flows the heat medium discharged from the heating terminal 39A, the heating terminal 39Z, etc. toward the heating-side heat exchanger 32. The heating return pipe 38C is configured to communicate with the heating terminal 39A and the heating terminal 39Z and is connected so as to be able to introduce the heat medium from the heating terminal 39A and the heating terminal 39Z.

[0035] Intermediate pipes 38D and 38E are provided between the outlet of the second heating-side heat exchanger 32B and the inlet of the first heating-side heat exchanger 32A, and an expansion tank 36 and a heating circulation pump 37 are provided in the path of the intermediate pipes 38D and 38E. The intermediate pipe 38D is provided between the outlet of the second heating-side heat exchanger 32B and the expansion tank 36, and the intermediate pipe 38E is provided between the expansion tank 36 and the inlet of the first heating-side heat exchanger 32A. A heating circulation pump 37 is provided in the middle of the intermediate pipe 38E.

[0036] The low-temperature heating supply pipe 38B branches off from a position downstream of the heating circulation pump 37 in the intermediate pipe 38E, and a plurality of internal branch paths 38F are provided in a configuration where they branch off from the low-temperature heating supply pipe 38B. A thermostatic valve 39G is provided in each internal branch path 38F as a valve for opening and closing each branch path 39F. In the example of FIG. 1, one internal branch path 38F communicates with the heating terminal 39Z and is connected so as to supply a heat medium from this internal branch path 38F to the heating terminal 39Z. The downstream side of the heating terminal 39Z communicates with the heating return pipe 38C on the downstream side of the heating terminal 39A. The heating terminal 39A is, for example, a high-temperature heating terminal such as a heating blower that blows warm air into a bathroom or a dressing room. The heating terminal 39Z is, for example, a low-temperature heating terminal such as floor heating in a dressing room.

[0037] The high-temperature heating thermostat 40 is provided in the high-temperature heating supply pipe 38A on the outlet side of the heating-side heat exchanger 32, and detects the temperature of the heat medium flowing out from the heating-side heat exchanger 32 (specifically, the heat medium flowing out from the first heating-side heat exchanger 32A). The temperature detected by the high-temperature heating thermostat 40 corresponds to the temperature of the heat medium flowing into the heating terminal 39A during the circulation of the heat medium passing through the heating terminal 39A. The low-temperature heating thermostat 41 is provided in the expansion tank 36. The temperature detected by the low-temperature heating thermostat 41 corresponds to the temperature of the heat medium flowing into the heating terminal 39Z during the circulation of the heat medium passing through the heating terminal 39Z.

[0038] The heating circuit 3 includes a plurality of branch pipes 16B and a plurality of heating switching solenoid valves 44. As described above, the branch pipe 16B is provided in a configuration branched from the gas pipe 16 to the heating circuit 3 side. Each heating switching solenoid valve 44 is provided in each branch pipe 16B. The heating switching solenoid valve 44 is configured to switch the branch pipe 16B in which it is provided between an open state (supply possible state) and a closed state (blocking state). The supply and blocking of the fuel gas to each of the burner blocks 34A, 34B are individually switched by each heating switching solenoid valve 44. By switching the heating switching solenoid valve 44, the combustion range of the heating-side burner unit 33 is switched, and each combustion range is associated as a number of steps. Note that the heating circuit 3 is also provided with an ignition electrode, a heating frame rod, and the like.

[0039] In the example of FIG. 1, the heating terminal 39A is configured as a high-temperature heating terminal, and hot water is supplied to the heating terminal 39A by the operation of the built-in thermostatic valve. The heating terminal 39Z is configured as a low-temperature heating terminal, and hot water is supplied to the heating terminal 39Z by the operation of the thermostatic valve in the appliance. In the heating circuit 3, the hot water heated by the heating-side heat exchanger 32 circulates through the heat medium circulation path 48 by the operation of the heating circulation pump 37. Specifically, in the heating circuit 3, when the heating circulation pump 37 operates, the hot water flowing through the heating return pipe 39C is heated by the combustion exhaust gas discharged from the heating-side burner unit 33 in the heating-side second heat exchanger 32B and the heating-side first heat exchanger 32A, and when the hot water heated by the heating-side heat exchanger 32 is in a state where it can be supplied to the heating terminal 39A (when the built-in thermostatic valve in the heating terminal 39A is in the open state), it circulates through the heating high-temperature forward pipe 38A, the heating terminal 39A, and the heating return pipe 39C, and when it is in a state where it can be supplied to the heating terminal 39Z (when the built-in thermostatic valve in the corresponding appliance is in the open state), it circulates through the heating low-temperature forward pipe 38B, the heating terminal 39Z, and the heating return pipe 39C.

[0040] As shown in FIG. 1, the bath heating pipe 51 is provided in a configuration branched from the heating high-temperature forward pipe 38A. The bath heating pipe 51 branches from a position downstream of the heating-side heat exchanger 32 in the heat medium circulation path 48 (specifically, downstream of the heating-side first heat exchanger 32A) and forms a flow path for guiding the heat medium flowing through the heat medium circulation path 48 to the bath heat exchanger 50 side. The bath heating pipe 51 is connected between the heating high-temperature forward pipe 38A and the heating return pipe 38C so as to communicate with each other.

[0041] The control valve 58 is a valve provided upstream of the bathtub heat exchanger 50 in the bathtub heating pipe 51. The control valve 58 is configured to open and close the bathtub heating pipe 51, and is configured to switch between a closed state in which the water flow passing through itself in the bathtub heating pipe 51 is blocked and an open state in which the water flow passing through itself in the bathtub heating pipe 51 is allowed. The control valve 58 has a switch. This switch is configured as a limit switch, and enters a first state in which a predetermined first signal (for example, an on signal) is output when the control valve 58 reaches its fully open state, and enters a second state in which a second signal (for example, an off signal) different from the first signal is output when the control valve 58 is in its fully closed state where it is blocked.

[0042] The water heater 1 further includes a control device 70, a hot water supply remote controller 71, a bathtub remote controller 72, and a room temperature thermistor (not shown). The control device 70 is an electronic control device including an information processing device such as a CPU, a memory such as a semiconductor memory device, an interface circuit, etc., and functions as a controller for performing various controls. Various programs, data tables, set values, etc. are stored in the memory. The control device 70 is configured to be able to acquire signals from each sensor and switch (thermistor, water volume sensor, switch, etc.), and controls the hot water supply circuit 2, the heating circuit 3, the bathtub circuit 4, etc. The room temperature thermistor is provided, for example, in the dressing room as a means for detecting the temperature in the dressing room.

[0043] 2. Basic operation of the water heater 1 (Normal hot water supply operation) For example, when the operations of the heating circuit 3 and the bath circuit 4 are stopped, if a hot water faucet provided outside the apparatus to communicate with the hot water pipe 10 is opened and water is passed into the appliance, and when the water volume sensor 14 outputs a signal indicating the passage of water, the control device 70 rotates the fan 20 for a predetermined time to discharge the combustion exhaust stored in the hot water combustion chamber 5A (purging). Then, the control device 70 opens the original gas solenoid valve 17 and each switching valve 19 of the gas pipe 16, opens the gas proportional valve 18 at a predetermined opening degree, controls to supply gas to each hot water burner 8A, and operates the igniter to ignite the hot water burner 8A. When gas is burned by the hot water burner 8A by such control, the water passing through the hot water side heat exchanger 7 is heated by the combustion exhaust generated by the combustion and flows to the hot water pipe 10, and a hot water discharging operation is performed so that the heated hot water is discharged from the above hot water faucet.

[0044] During the above hot water discharging operation, the control device 70 monitors the hot water temperature detected by the thermistor 15B provided in the hot water pipe 10, and performs opening / closing control of the switching valve 19 and adjustment of the opening degree of the gas proportional valve 18 so that the hot water temperature becomes the set temperature indicated by the hot water remote controller 71 or the bath remote controller 72, and continuously changes the air volume by controlling the rotation speed of the fan 20. When the above hot water faucet is closed during the above hot water discharging operation and the signal output by the water volume sensor 14 becomes a signal indicating a water passage stop state, and when the operations of the heating circuit 3 and the bath circuit 4 are stopped, the control device 70 closes the original gas solenoid valve 17 and the switching valve 19 to extinguish the hot water burner 8A, and rotates the fan 20 for a predetermined time to perform post-purging.

[0045] (Automatic hot water filling operation) The control device 70 can perform control to automatically fill the bathtub 52 with hot water. For example, when the hot water filling switch provided on the hot water supply remote control 71 or the bathtub remote control 72 is pressed, the control device 70 sets the hot water outlet temperature to the hot water filling temperature set on the hot water supply remote control 71 or the bathtub remote control 72 as the target temperature (e.g., 40 °C) and starts hot water filling. Specifically, the control device 70 opens the hot water supply solenoid valve 60 of the drop pipe 59 to put the hot water supply circuit 2 into a water flow state, and burns the hot water supply burner 8A so that the heated hot water flows into the hot water outlet pipe 10. The hot water flowing through the hot water outlet pipe 10 in this way is supplied to the bathtub 52 through the drop pipe 59 and the bathtub return pipe 54.

[0046] After the control device 70 starts supplying hot water to the bathtub 52 in this way, it monitors whether the water volume detected by the drop water volume sensor 61 provided in the drop pipe 59 (total water volume since the start of automatic hot water filling) has reached the set water volume. When it is confirmed that the water volume has reached, the control device closes the hot water supply solenoid valve 60 to stop the water flow, extinguishes the hot water supply burner 8A, and ends the hot water filling. After that, the control device 70 operates the bathtub circulation pump 55 to circulate the hot water in the bathtub 52 within the bathtub circuit 4. During this circulation, the heating circuit 3 is operated and the control valve 58 is kept open. After the control device 70 starts such a circulation operation after hot water filling, it monitors whether the hot water temperature detected by the bathtub return thermistor 65 has reached the target temperature. When it is confirmed that the hot water temperature has reached, the control device stops the bathtub circulation pump 55 and ends the automatic hot water filling. When the control device 70 ends the automatic hot water filling, it notifies the end of the automatic hot water filling on the hot water supply remote control 71 or the bathtub remote control 72.

[0047] (Automatic reheating operation) The control device 70 can perform control to automatically reheat (boil up) the water stored in the bathtub 52. For example, when the reheat switch provided on the hot water supply remote control 71 or the bath remote control 72 is pressed, the control device 70 sets the reheat temperature to the target temperature (e.g., 40°C) set on the hot water supply remote control 71 or the bath remote control 72 and starts the reheat. Specifically, the control device 70 ignites the heating burner 33A, keeps the control valve 58 open, operates the bath circulation pump 55, and performs reheat by heating with the bath heat exchanger 50 while circulating the hot water in the bathtub 52. After starting such reheat, the control device 70 monitors whether the hot water temperature detected by the bath return thermistor 65 has reached the target temperature. When it is confirmed that the temperature has reached, the control device 70 stops the bath circulation pump 55 and ends the reheat. When the control device 70 ends the reheat, it notifies the end of the reheat to the hot water supply remote control 71 or the bath remote control 72.

[0048] 3. Combustion operation of the hot water supply and heating machine 1 When the hot water supply circuit 2 performs a hot water supply operation, the control device 70 calculates the required combustion amount required by the hot water supply side burner unit 8 according to the temperature of the hot water detected by the thermistors 15A and 15B, and controls the opening degree of the gas proportional valve 18 and the opening and closing of the switching valve 19 so that the obtained required combustion amount is obtained, thereby controlling the gas supply amount. Then, the target rotation speed of the fan 20 is controlled so that the supply amount of combustion air corresponds to the gas supply amount. The gas supply amount is the "combustion amount" and the "input required amount". Specifically, the gas supply amount is the supply amount of gas to the hot water supply side burner unit 8 per unit time.

[0049] Specifically, the control device 70 calculates the gas supply amount (input required amount) by a known calculation method based on the current water amount (inlet water amount) detected by the water amount sensor 14, the set temperature (target value of the outlet water temperature) set as the target temperature, and the current temperature (outlet water temperature) detected by the thermistor 15B at each short time interval. The gas supply amount (input required amount) is updated each time it is calculated, and the fan rotation speed is updated to correspond to the updated gas supply amount (input required amount). The water amount detected by the water amount sensor 14 is the amount of water flowing through the position of the water amount sensor 14 per unit time. The calculation method of the gas supply amount (input required amount) may be a feedback operation that brings the outlet water temperature closer to the set temperature. For example, it may be a method disclosed in Japanese Patent Application Laid-Open No. 2010-117053, or it may be a method disclosed in Japanese Patent Application Laid-Open No. 2018-200123, or any other known method. In any case, the control device 70 performs a feedback operation to calculate the gas supply amount so as to bring the outlet water temperature closer to the target temperature at each short time interval. Each time the gas supply amount is calculated, the opening degree of the gas proportional valve 18 and the opening and closing of the switching valve 19 are controlled to be the newly calculated gas supply amount. Then, the control device 70 executes control to change the fan rotation speed each time the gas supply amount (input required amount) is updated according to an arithmetic expression or a table that defines the correspondence relationship between the gas supply amount (combustion amount) and the fan rotation speed.

[0050] In the example of FIG. 1, the burner blocks 9A, 9B, and 9C each consist of a plurality of burners with different numbers. Among the burner blocks 9A, 9B, and 9C, the burner block 9C has the largest number of gas burners, the burner block 9A has the smallest number of gas burners, and the burner block 9B has fewer gas burners than the burner block 9C and more gas burners than the burner block 9A. In the hot water temperature control for controlling the hot water temperature, the control device 70 first performs single combustion of only the burner block 9A with the smallest number of burners in one stage, then single combustion of only the burner block 9B with a larger number of burners in two stages, then simultaneous combustion of the burner blocks 9A and 9B with an increasing number of burners in three stages, then single combustion of the burner block 9C with an increasing number of burners in four stages, and full combustion of the burner blocks 9A to 9C with the largest number of burners in five stages. The control device 70 executes switching control to switch the combustion stage (hereinafter, also referred to as the combustion stage or combustion step) of the hot water supply side burner unit 8 in five stages according to the required gas supply amount (input required amount).

[0051] When the heating side burner unit 33 is not burned and the hot water supply side burner unit 8 is burned, the stage control is as follows. In a representative example, as shown in FIG. 2, for each combustion stage, the correspondence relationship between the gas supply amount (input required amount) and the target rotation speed of the fan is determined in advance. In the correspondence relationship of any combustion stage, it is determined that the larger the gas supply amount (input required amount), the larger the target rotation speed. The information on the correspondence relationship of each combustion stage is stored in a storage device provided in the control device 70, such as an arithmetic formula or a table for determining the target rotation speed based on the gas supply amount (input required amount). When the combustion stage and the gas supply amount are determined, the target rotation speed corresponding to the combustion stage and the gas supply amount is specified by the above information.

[0052] For example, in the above information (information defining the correspondence between the gas supply amount (input requirement amount) and the target rotational speed of the fan for each combustion stage), the upper limit value (first upper limit value) of the input requirement amount for the first combustion stage is greater than the lower limit value (second lower limit value) of the input requirement amount for the second combustion stage. The upper limit value (second upper limit value) of the input requirement amount for the second combustion stage is greater than the lower limit value (third lower limit value) of the input requirement amount for the third combustion stage. The upper limit value (third upper limit value) of the input requirement amount for the third combustion stage is greater than the lower limit value (fourth lower limit value) of the input requirement amount for the fourth combustion stage. The upper limit value (fourth upper limit value) of the input requirement amount for the fourth combustion stage is greater than the lower limit value (fifth lower limit value) of the input requirement amount for the fifth combustion stage. The correspondence between the gas supply amount (input requirement amount) and the target rotational speed of the fan at each combustion stage is a correspondence in which the rotational speed of the fan increases as the gas supply amount (input requirement amount) increases.

[0053] In the above information, the target rotational speed when the upper limit value (first upper limit value) of the input requirement amount for the first combustion stage is greater than the target rotational speed when the lower limit value (second lower limit value) of the input requirement amount for the second combustion stage. The target rotational speed when the upper limit value (second upper limit value) of the input requirement amount for the second combustion stage is greater than the target rotational speed when the lower limit value (third lower limit value) of the input requirement amount for the third combustion stage. The target rotational speed when the upper limit value (third upper limit value) of the input requirement amount for the third combustion stage is greater than the target rotational speed when the lower limit value (fourth lower limit value) of the input requirement amount for the fourth combustion stage. The target rotational speed when the upper limit value (fourth upper limit value) of the input requirement amount for the fourth combustion stage is greater than the target rotational speed when the lower limit value (fifth lower limit value) of the input requirement amount for the fifth combustion stage.

[0054] When the control device 70 is burning in any stage, if the input required amount is less than the lower limit value of that combustion stage, it switches to a stage lower than that combustion stage and determines the fan rotation speed corresponding to the input required amount according to the characteristics of the stage after switching. When the input required amount exceeds the upper limit value of that combustion stage, the control device 70 switches to a stage higher than that combustion stage and determines the fan rotation speed corresponding to the input required amount according to the characteristics of the stage after switching. For example, when burning in the first stage and the input required amount changes, and the required combustion amount exceeds the maximum value of the first stage, it switches to the second stage and burns the burner block 9B. When switching from the first stage to the second stage, it is set to the fan rotation speed corresponding to the input required amount according to the characteristic line of the second stage. Similarly, when the input required amount changes in the state of the second stage and the input required amount exceeds the maximum value of the second stage, it switches to the third stage and burns the burner blocks 9A and 9B. When switching from the second stage to the third stage, it is set to the fan rotation speed corresponding to the input required amount according to the characteristic line of the third stage. Conversely, when the input required amount changes in the state of the third stage and the input required amount is less than the minimum value of the third stage, it switches to the second stage and burns the burner block 9B. When switching from the third stage to the second stage, it is set to the fan rotation speed corresponding to the input required amount according to the characteristic line of the second stage.

[0055] In the example of FIG. 1, the burner blocks 34A and 34B are composed of a plurality of burners with different numbers from each other. Among the burner blocks 34A and 34B, the burner block 34B has more gas burners than the burner block 34A, and the burner block 34A has fewer gas burners. When the control device 70 burns the heating side burner unit 33, it sets the single combustion of only the burner block 34A with the smallest number of burners as the first stage, then the single combustion of only the burner block 34B with more burners as the second stage, and then the full combustion of the burner blocks 34A and 34B with an increasing number of burners as the third stage, and executes switching control to switch the combustion stage (hereinafter, also referred to as the combustion stage or combustion step) of the heating side burner unit 33 to three stages according to the required gas supply amount (input required amount).

[0056] When the heating-side burner unit 33 is burned without burning the hot water supply-side burner unit 8, the stage control is as follows. The stage switching in the heating-side burner unit 33 is also performed in the same manner as the hot water supply-side burner unit 8. Regarding the heating-side burner unit 33 as well, for each combustion stage, the correspondence relationship between the gas supply amount (input required amount) and the target rotation speed of the fan is determined in advance, and in the correspondence relationship of any combustion stage, it is determined that the larger the gas supply amount (input required amount), the larger the target rotation speed. The information on the correspondence relationship of each combustion stage is stored in a storage device provided in the control device 70, such as an arithmetic expression or a table for determining the target rotation speed based on the gas supply amount (input required amount). When the combustion stage and the gas supply amount are determined, the target rotation speed corresponding to the combustion stage and the gas supply amount is specified by the above information.

[0057] Even in the stage switching of the heating-side burner unit 33, the upper limit value (first upper limit value) of the input required amount in the first combustion stage is larger than the lower limit value (second lower limit value) of the input required amount in the second combustion stage, and the upper limit value (second upper limit value) of the input required amount in the second combustion stage is larger than the lower limit value (third lower limit value) of the input required amount in the third combustion stage. Even in the stage switching of the heating-side burner unit 33, the correspondence relationship between the gas supply amount (input required amount) and the target rotation speed of the fan in each combustion stage is a correspondence relationship in which the rotation speed of the fan increases as the gas supply amount (input required amount) increases.

[0058] The target rotation speed at the upper limit value (the first upper limit value) of the input required amount in the first combustion stage is higher than the target rotation speed at the lower limit value (the second lower limit value) of the input required amount in the second combustion stage. The target rotation speed at the upper limit value (the second upper limit value) of the input required amount in the second combustion stage is higher than the target rotation speed at the lower limit value (the third lower limit value) of the input required amount in the third combustion stage. Also in this example, when burning in any stage, if the input required amount falls below the lower limit value of the current combustion stage, the control device 70 switches to a stage lower than the current combustion stage and determines the fan rotation speed (target rotation speed) corresponding to the input required amount according to the characteristics of the stage after switching. When the input required amount exceeds the upper limit value of the current combustion stage, the control device 70 switches to a stage higher than the current combustion stage and determines the fan rotation speed corresponding to the input required amount according to the characteristics of the stage after switching.

[0059] 4. Detection of clogging In the water heater 1 according to the present embodiment, a plurality of fins 7Z are provided on the water supply side heat exchanger 7 (the first heat exchanger) and the heating side heat exchanger 32 (the second heat exchanger), enhancing heat transfer performance. However, if clogging occurs between the fins of the fins 7Z that suppress the flow of gas between the fins, the smooth flow of the gas will be hindered. Therefore, in the water heater 1, the control device 70 functions as an example of an abnormality detection unit and detects an abnormality in the gas flow in the housing 1A (specifically, an abnormality of clogging to a certain extent). The control device 70 uses in combination a first detection method for detecting an abnormality in the gas flow in the housing 1A based on the current supplied to the fan 20 and a second detection method for detecting an abnormality in the gas flow in the housing 1A based on the temperature detected by the temperature sensor 82.

[0060] The hot water heating apparatus 1 is provided with the above-described fan 20, and the fan 20 operates to supply air into the housing 1A. The fan 20 has a rotating body 20B that generates wind by its rotation and a drive source 20A that rotates the rotating body 20B, and is configured such that the rotational speed of the rotating body 20B increases as the current applied to the drive source 20A increases. The fan 20 may be a sirocco fan, a propeller fan, or other fans. The rotating body 20B is, for example, a rotating body 20B that has blades and the air volume increases as its rotational speed increases. The drive source 20A is, for example, a motor that rotates the rotating body 20B, and may be a DC motor or an AC motor. The control device 70 functions as an example of a fan control device that controls the rotation of the fan 20. The fan 20 is provided with means for detecting the rotational speed of the rotating body 20B. The control device 70 includes a drive circuit that controls the current applied to the drive source 20A, is capable of grasping the rotational speed of the rotating body 20B, and performs feedback control to increase or decrease the current applied to the drive source 20A so that the rotational speed of the fan 20 approaches the target rotational speed based on the deviation between the target rotational speed and the current rotational speed. When the rotating body 20B is rotating at a certain rotational speed, the rotational speed of the rotating body 20B increases as the amount of increase in the current applied to the drive source 20A increases, and the rotational speed of the rotating body 20B decreases as the amount of decrease in the current applied to the drive source 20A increases. How fast the rotating body 20B rotates when a certain value of current is supplied to the drive source 20A is determined by not only the configuration of the drive source 20A but also the influence of the external environment such as the gas flow state. The feedback control may be PID control, PI control, fuzzy control, or other control.

[0061] In this configuration, as clogging occurs near the fins 7Z and it becomes difficult for the gas to flow, the torque (load) of the rotating body 20B increases. Therefore, when maintaining a predetermined rotational speed, as clogging occurs near the fins 7Z and it becomes difficult for the gas to flow, the required current increases by the amount of the increased torque (load). When the control device 70 employs the first detection method, it determines that the gas flow in the housing 1A is abnormal when the current supplied to the fan 20 (i.e., the current supplied to the drive source 20A) becomes equal to or greater than the reference value, and determines that the gas flow in the housing 1A is normal when the current supplied to the fan 20 (i.e., the current supplied to the drive source 20A) is less than the reference value. The reference value may be a predetermined fixed value. Alternatively, the reference value may be a value determined for each rotational speed. For example, in an example where the reference value is determined for each rotational speed, when the fan 20 is controlled so as to have a rotational speed corresponding to the gas supply amount (input required amount) calculated by arithmetic operation, it is determined that the gas flow in the housing 1A is abnormal when the current supplied to the drive source 20A becomes equal to or greater than the reference value associated with the rotational speed, and it may be determined that the gas flow in the housing 1A is normal if it is less than the reference value.

[0062] In the hot water supply and heating apparatus 1, in the above-described housing 1A, a partition member 80 is provided so as to partition the hot water supply combustion chamber 5A and the heating combustion chamber 6A in the housing 1A. That is, the internal space of the housing 1A is partitioned into a hot water supply combustion chamber 5A that houses the hot water supply burner 8A (first burner) and the hot water supply side heat exchanger 7 (first heat exchanger), and a heating combustion chamber 6A that houses the heating burner 33A (second burner) and the heating side heat exchanger 32 (second heat exchanger) by the partition member 80. The partition member 80 functions as the inner wall on the heating combustion chamber 6A side in the hot water supply combustion chamber 5A and functions as the inner wall on the hot water supply combustion chamber 5A side in the heating combustion chamber 6A. Therefore, the path of the gas flowing upward by the blowing of the fan 20 is divided into a path that flows through the hot water supply combustion chamber 5A on one side of the partition member 80, passes between the plurality of fins 7Z of the hot water supply side heat exchanger 7, and is discharged from the exhaust port, and a path that flows through the heating combustion chamber 6A on the other side of the partition member 80, passes between the plurality of fins 32Z of the heating side heat exchanger 32, and is discharged from the exhaust port.

[0063] In such a configuration, a temperature sensor 82 for detecting the temperature of the heating combustion chamber 6A is provided in the partition member 80. The temperature sensor 82 may be configured to be completely embedded inside the partition member 80 without being exposed, or may be configured such that a part thereof is exposed to the space of the heating combustion chamber 6A. The temperature sensor 82 is disposed at a position higher than that of the plurality of heating burners 33A.

[0064] When the control device 70 adopts the second detection method, it determines whether there is an abnormality based on whether the temperature detected by the temperature sensor 82 is in a predetermined temperature rising state. Specifically, when the temperature detected by the temperature sensor 82 is equal to or higher than the temperature threshold, it is determined that the gas flow in the container 1A is abnormal, and when the temperature detected by the temperature sensor 82 is lower than the temperature threshold, it is determined that the gas flow in the container 1A is normal.

[0065] In this way, the control device 70 is capable of selecting the first detection method and the second detection method. When the control device 70 satisfies a predetermined first condition, it adopts the above-described first detection method and determines whether there is an abnormality based on whether the current applied to the drive source 20A is in a predetermined current rising state. When the control device 70 satisfies a predetermined second condition (a condition different from the first condition), it adopts the above-described second detection method and determines whether there is an abnormality based on whether the temperature detected by the temperature sensor 82 is in a predetermined temperature rising state.

[0066] In the representative example, when all the hot water burners 8A (first burners) in the hot water combustion chamber 5A are in a non-combustion state and the heating burner 33A (second burner) closest to the partition member 80 in the heating combustion chamber 6A is in a combustion state, this satisfies the second condition. The above-mentioned "heating burner 33A closest to the partition member 80" means, that is, among the plurality of burner blocks 34A, 34B in the heating combustion chamber 6A, it is the heating burner 33A of the burner block (burner block 34A) closest to the partition member 80. That is, in the representative example, when all the hot water burners 8A (first burners) in the hot water combustion chamber 5A are in a non-combustion state and the heating burner 33A (second burner) of the burner block 34A in the heating combustion chamber 6A is in a combustion state, this satisfies the second condition.

[0067] When the control device 70 satisfies this second condition, if the temperature detected by the temperature sensor 82 is equal to or higher than the temperature threshold value, it determines that the gas flow in the container 1A is abnormal (more specifically, it determines that there is a blockage between the plurality of fins 34Z in the heating combustion chamber 6A). When the control device 70 satisfies the second condition and the temperature detected by the temperature sensor 82 is lower than the temperature threshold value, it determines that the gas flow in the container 1A is normal (more specifically, it determines that there is no blockage between the plurality of fins 34Z in the heating combustion chamber 6A). Note that the case where the heating burner 33A closest to the partition member 80 is in a combustion state may be a case where all of the plurality of burner blocks 34A, 34B are in a combustion state, or may be a case where only a part including the burner block (burner block 34A) closest to the partition member 80 is in a combustion state.

[0068] In a representative example, a case where the hot water burner 8A (first burner) is in a combustion state in the hot water combustion chamber 5A satisfies the first condition. When this first condition is satisfied, the control device 70 determines that the gas flow in the container 1A is abnormal if the current supplied to the fan 20 (that is, the current supplied to the drive source 20A) is equal to or greater than the above reference value (more specifically, it is determined that there is a clog between the plurality of fins 7Z in the hot water combustion chamber 5A). When the first condition is satisfied and the current supplied to the fan 20 (that is, the current supplied to the drive source 20A) is less than the above reference value, it is determined that the gas flow in the container 1A is normal (more specifically, it is determined that there is no clog between the plurality of fins 7Z in the hot water combustion chamber 5A).

[0069] In a representative example, when all the hot water burners 8A (first burners) are in a non-combustion state in the hot water combustion chamber 5A, the heating burner 33A (second burner) closest to the partition member 80 is in a non-combustion state in the heating combustion chamber 6A, and the heating burner 33A (second burner) farther from the partition member 80 than the heating burner 33A (second burner) closest to the partition member 80 is in a combustion state, the control device 70 does not perform the above abnormality detection. The "heating burner 33A farther from the partition member 80" in this case is, that is, the heating burner 33A of the burner block 34B that is not the burner block (burner block 34A) closest to the partition member 80 among the plurality of burner blocks 34A, 34B in the heating combustion chamber 6A.

[0070] When the control device 70 determines that the gas flow in the container 1A is abnormal, it may give an alarm for the abnormality. The alarm for the abnormality may be an alarm that displays an error code indicating that the gas flow in the container 1A is abnormal on the display unit, may be an alarm that displays an error message on the display unit, or may be a buzzer sound or voice output of an error message. When the control device 70 determines that the gas flow in the container 1A is abnormal, if the abnormality is detected by the first detection method, the abnormality is reported by the first reporting method, and if the abnormality is detected by the second detection method, the abnormality is reported by the second reporting method. The reporting method when the abnormality is detected by the first detection method and the reporting method when the abnormality is detected by the second detection method may be made different. In this way, it is easy to know which part is clogged.

[0071] 5. Examples of effects In the water heater 1, when clogging occurs between the fins of the plurality of fins 7Z in the water heating combustion chamber 5A, the upward flow of the gas in the water heating combustion chamber 5A is obstructed, and the torque for rotating the rotating body 20B of the fan 20 increases. Therefore, in order to rotate the rotating body 20B at the same rotational speed, the current supplied to the drive source 20A increases. The water heater 1 utilizes such a change and determines whether an abnormal clogging has occurred between the fins of the water heating combustion chamber 5A by determining whether the current applied to the drive source 20A is in a predetermined current increase state during combustion in the water heating combustion chamber 5A, and can more accurately determine whether an abnormal clogging has occurred.

[0072] On the other hand, when the burner block in the hot water combustion chamber 5A is in a non-combustion state, that is, when the first burner in the hot water combustion chamber 5A is in a non-combustion state, the temperature detected by the temperature sensor 82 is used to determine whether there is an abnormality such as clogging between the fins of the plurality of fins 32Z in the heating combustion chamber 6A. When determining the abnormality on the heating combustion chamber 6A side in this way, when the first burner is in a non-combustion state in the hot water combustion chamber 5A and the burner block 34A closest to the partition member 80 is in a combustion state in the heating combustion chamber 6A, the abnormality is determined based on whether the temperature detected by the temperature sensor 82 is in a predetermined temperature rising state. When the burner block 34A closest to the partition member 80 in the heating combustion chamber 6A is in a combustion state, it means that the temperature sensor 82 (the sensor that detects the temperature of the heating combustion chamber 6A) provided on the partition member 80 is likely to be affected by the combustion of the second burner. That is, when the flame extends upward due to clogging between the fins in the heating combustion chamber 6A, the detected temperature of the temperature sensor 82 is likely to rise. In such a case, if the abnormality is determined based on whether the temperature detected by the temperature sensor 82 is in a predetermined temperature rising state, it is possible to more accurately determine whether there is an abnormality such as clogging between the fins in the heating combustion chamber 6A.

[0073] On the other hand, in the hot water and heating machine 1, when all the burner blocks in the hot water combustion chamber 5A are in a non-combustion state, the burner block 34A closest to the partition member 80 in the heating combustion chamber 6A is in a non-combustion state, and the burner block 34B farther from the partition member 80 than the closest burner block 34A is in a combustion state, it means that it is during the combustion of only the heating combustion chamber 6A among the hot water combustion chamber 5A and the heating combustion chamber 6A, and the temperature sensor 82 provided on the partition member 80 is less likely to be affected by the combustion of the second burner. If the detection of the abnormality is not performed in such a case, it is possible to prevent an incorrect determination of the abnormality caused by the fact that the influence of the combustion of the second burner is less likely to reach the temperature sensor 82.

[0074] <Other Embodiments> The present invention is not limited to the embodiments described by the above description and drawings. For example, the features of the above-described or below-described embodiments can be combined in any combination within a non-contradictory range. Also, any feature of the above-described or below-described embodiments can be omitted if it is not explicitly specified as essential. Furthermore, the above-described embodiments may be modified as follows.

[0075] In the above-described embodiment, when the first burner is in a non-combustion state in the hot water combustion chamber 5A, the second burner closest to the partition member 80 in the heating combustion chamber is in a non-combustion state, and the second burner farther from the partition member 80 than the second burner closest to the partition member 80 is in a combustion state, no abnormality detection is performed. However, in this case, an abnormality may be detected by a method different from both the first detection method and the second detection method.

[0076] In the above-described embodiment, the case where the temperature detected by the temperature sensor 82 is equal to or higher than the temperature threshold value is the "predetermined temperature rise state". However, the case where the rate of increase per unit time of the temperature detected by the temperature sensor 82 is equal to or higher than a predetermined value may be the "predetermined temperature rise state", or the case where the temperature detected by the temperature sensor 82 is equal to or higher than the temperature reference value and the rate of increase per unit time of the detected temperature is equal to or higher than a predetermined value may be the "predetermined temperature rise state".

[0077] In the above-described embodiment, the case where the value of the current applied to the drive source 20A is equal to or higher than the reference value is the "predetermined current rise state". However, the case where the rate of increase per unit time of the current applied to the drive source 20A is equal to or higher than a predetermined value may be the "predetermined current rise state", or the case where the current applied to the drive source 20A is equal to or higher than the reference value and the rate of increase per unit time of the current applied to the drive source 20A is equal to or higher than a predetermined value may be the "predetermined current rise state".

[0078] It should be noted that the embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present invention is not limited to the embodiments disclosed this time, and it is intended that all modifications within the scope indicated by the claims or within the scope equivalent to the claims are included.

Explanation of Signs

[0079] 1: Hot water supply and heating machine 1A: Container 2: Hot water supply circuit 3: Heating circuit 4: Bath circuit 5A: Hot water supply combustion chamber 6A: Heating combustion chamber 7: Hot water supply side heat exchanger (first heat exchanger) 7Z: Fin 8: Hot water supply side burner unit 8A: Hot water supply burner (first burner) 9A: Burner block 9B: Burner block 9C: Burner block 10: Hot water outlet pipe 11: Water supply pipe 20: Fan 20A: Driving source 20B: Rotating body 32: Heating side heat exchanger (second heat exchanger) 32Z: Fin 33: Heating side burner unit 33A: Heating burner (second burner) 34A: Burner block 34B: Burner block 39A: Heating terminal 39Z: Heating terminal 48: Heat medium circulation path 70: Control device (fan control device, abnormality detection unit) 80: Partition member 82: Temperature sensor

Claims

1. a hot water supply circuit including a first burner for burning gas and a first heat exchanger heated by exhaust gas generated by the first burner, the hot water supply circuit heating water supplied from the outside by the first heat exchanger to supply hot water; a heating circuit including a second burner that burns gas, a second heat exchanger that is heated by exhaust gas generated by the second burner, and a heat medium circulation path that is a path for circulating a heat medium through the second heat exchanger, the heating circuit heating the heat medium by the second heat exchanger and supplying the heat medium to a heating terminal via the heat medium circulation path; a housing that houses the first burner, the second burner, the first heat exchanger, and the second heat exchanger; A partition member that divides the inside of the container; A fan for supplying air into the container; A fan control device that controls the fan; A temperature sensor provided in the partition member; an abnormality detection unit that detects an abnormality in the flow of gas within the container; Equipped with Within the container, a hot water supply combustion chamber accommodating the first burner and the first heat exchanger and a heating combustion chamber accommodating the second burner and the second heat exchanger are partitioned by the partition member, The entire area in which the first burner is arranged in the hot water supply combustion chamber is divided into a plurality of burner blocks, and the entire area in which the second burner is arranged in the heating combustion chamber is divided into a plurality of burner blocks, The temperature sensor is arranged to detect a temperature of the heating combustion chamber; The first heat exchanger and the second heat exchanger are provided with a plurality of fins, the fan has a rotor and a drive source for rotating the rotor, and is configured such that the rotation speed of the rotor increases as the current applied to the drive source increases; the fan control device controls the rotation speed of the rotor by increasing or decreasing the current applied to the drive source, The abnormality detection unit When any of the burner blocks in the hot water supply combustion chamber is in a combustion state, the abnormality is determined based on whether or not a current given to the driving source is in a predetermined current increase state; When all the burner blocks in the hot water supply combustion chamber are in a non-combustion state and the burner block closest to the partition member in the heating combustion chamber is in a combustion state, the abnormality is determined based on whether the temperature detected by the temperature sensor is in a predetermined temperature rise state. Hot water heater.

2. The abnormality detection unit does not detect the abnormality when all the burner blocks in the hot water supply combustion chamber are in a non-combustion state, the burner block closest to the partition member in the heating combustion chamber is in a non-combustion state, and the burner block farther from the partition member than the burner block closest to the partition member is in a combustion state. The hot water heater according to claim 1.

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