Hot water supply heater

Abstract

To determine an opening / closing abnormality of a control valve in a hot water supply heater capable of opening / closing a branch passage branched from a position downstream of a heat exchanger in a heating circuit by using the control valve.SOLUTION: Bath heating piping 51 is a branch passage branched from a position downstream of a second heat exchanger 32 in a heating medium circulation passage 48. The bath heating piping 51 guides a heating medium caused to flow in the heating medium circulation passage 48 to a bath heat exchanger 50 side that is a liquid-liquid heat exchanger. A switch is provided in a control valve 58 for opening / closing the bath heating piping 51. The switch becomes a first state when the control valve 58 becomes an opened state, and becomes a second state when the control valve 58 becomes a closed state. The control device 70 controls the control valve 58, and performs a confirmation operation for causing the control valve 58 to become the opened state and the closed state when a heating circuit 3 is in a predetermined non-operation state. The control device 70 performs determination control for determining whether the switch is switched to the first state and the second state during the confirmation operation.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] Patent Document 1 discloses an example of a combined heat source machine. This combined heat source machine has both a heating circuit and a reheating circuit. The heating circuit is configured to simultaneously circulate high-temperature water to the high-temperature heating terminal and low-temperature water to the low-temperature heating terminal. The reheating circuit is configured to perform reheating heating by forced circulation of bath water. The heating circuit includes a high-temperature bypass path that is diverted midway through the high-temperature water supply so as to bypass the high-temperature heating terminal, and a liquid-liquid heat exchanger is provided midway between this high-temperature bypass path and the reheating circuit. The combined heat source machine is configured to perform reheating heating of the bath water by performing liquid-liquid heat exchange with the bath water using the high-temperature water as a heat source. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-46858 A Summary of the Invention [Problem to be solved by the invention]

[0004] The combined heat source device of Patent Document 1 is provided with a thermal valve as an on-off switching valve (reheating control valve) in the first high-temperature bypass passage, and the supply and cut-off of high-temperature water to the liquid-liquid heat exchanger is switched by switching the on-off of this thermal valve. However, in this type of device, for example, if the on-off switching valve (reheating control valve) breaks down and cannot be switched to the open state, it becomes impossible to flow high-temperature water into the liquid-liquid heat exchanger, and reheating in the reheating circuit (bath circuit) becomes impossible.

[0005] One of the objects of the present disclosure is to provide a technology that can determine abnormalities in the opening and closing of a control valve in a hot water heater that has a hot water circuit, a heating circuit, and a bath circuit, and in which a branch path that branches off from a position downstream of a heat exchanger in the heating circuit can be opened and closed using a control valve. [Means for solving the problem]

[0006] The hot water heater according to the present disclosure includes: 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, and for supplying hot water by heating water supplied from the outside using the first heat exchanger; 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, in which the heat medium is heated by the second heat exchanger and the heat medium is supplied to a heating terminal via the heat medium circulation path; A bath circuit having a bath circulation path that circulates hot and cold water drawn from an external bathtub and introduces it into the external bathtub; A liquid-liquid heat exchanger that exchanges heat with the hot water flowing through the bath circulation path; a branch path that branches off from a position downstream of the second heat exchanger in the heat medium circulation path and guides the heat medium that has flowed through the heat medium circulation path to the liquid-liquid heat exchanger; a control valve that opens and closes the branch passage; a switch that is in a first state when the control valve is in an open state and in a second state when the control valve is in a closed state; A control device for controlling the control valve; Equipped with The control device performs a confirmation operation one or more times to switch the control valve between the open state and the closed state when the heating circuit is in a predetermined non-operating state, and performs a determination control to determine whether the switch has switched between the first state and the second state during the confirmation operation. Effect of the Invention

[0007] According to the technology disclosed herein, in a hot water heater that has a hot water circuit, a heating circuit, and a bath circuit, and in which a branch path that branches off from a position downstream of a heat exchanger in the heating circuit can be opened and closed using a control valve, abnormalities in the opening and closing of the control valve can be determined. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic circuit diagram illustrating a configuration of a hot water heater according to a first embodiment. [Diagram 2] FIG. 2 is a flowchart illustrating a flow of heating control of the heating circuit in the hot water heater according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Each of the following [1] and [2] is an example of a characteristic technique included in this disclosure.

[0010] [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, and for supplying hot water by heating water supplied from the outside using the first heat exchanger; 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, in which the heat medium is heated by the second heat exchanger and the heat medium is supplied to a heating terminal via the heat medium circulation path; A bath circuit having a bath circulation path that circulates hot and cold water drawn from an external bathtub and introduces it into the external bathtub; A liquid-liquid heat exchanger that exchanges heat with the hot water flowing through the bath circulation path; a branch path that branches off from a position downstream of the second heat exchanger in the heat medium circulation path and guides the heat medium that has flowed through the heat medium circulation path to the liquid-liquid heat exchanger; a control valve that opens and closes the branch passage; a switch that is in a first state when the control valve is in an open state and in a second state when the control valve is in a closed state; A control device for controlling the control valve; Equipped with The control device performs a confirmation operation to switch the control valve between the open state and the closed state at least once when the heating circuit is in a predetermined non-operating state, and performs a determination control to determine whether or not the switch has switched between the first state and the second state during the confirmation operation. Hot water heater.

[0011] In the hot water heater described above in [1], the branch passage branching off from the downstream side of the heat exchanger in the heating circuit can be opened and closed by the control valve. In such a hot water heater, an abnormality in the opening and closing of the control valve can be determined.

[0012] [2] The predetermined non-operating state is a state after the condition for operating the heating circuit is satisfied and before the operation of the heating circuit starts. The hot water heater according to [1].

[0013] The hot water heater described above in [2] can determine whether or not the control valve is abnormal every time the heating circuit is heated, before the heating circuit is heated. Therefore, this hot water heater can reduce the risk of the control valve being left undiscovered as an abnormality.

[0014] First Embodiment The following description relates to a hot water heater 1 according to the first embodiment. 1. Overall configuration of hot water heater 1 1 is a schematic circuit diagram of a hot water heater 1. The hot water heater 1 includes a hot water circuit 2, a heating circuit 3, and a bath circuit 4.

[0015] The hot water supply circuit 2 is a circuit that supplies hot water by heating water supplied from outside the hot water heater 1 using a first heat exchanger 7. The hot water supply circuit 2 includes a hot water supply combustion chamber 5, and includes a plurality of hot water supply burners 6 and a first heat exchanger 7 within the hot water supply combustion chamber 5. The first heat exchanger 7 functions as a hot water supply side heat exchanger, and heats the water passing through the inside thereof with the combustion exhaust of the plurality of hot water supply burners 6. Each of the plurality of hot water supply burners 6 is configured as a gas burner that burns gas, and corresponds to an example of a first burner. The first heat exchanger 7 corresponds to an example of a first heat exchanger, and is configured to be heated by the exhaust generated by the first burner.

[0016] The hot water supply circuit 2 further includes a water supply pipe 8, a hot water supply amount sensor 9, a hot water outlet pipe 10, a bypass pipe 12, a bypass control valve 13, a hot water supply inner body thermistor 14, and a hot water supply outlet thermistor 15. The water supply pipe 8 is connected to an inlet of the first heat exchanger 7. The water supply pipe 8 is connected to an external piping, and is configured as a pipe that introduces tap water from a water supply, for example, and flows this tap water toward the first heat exchanger 7. The water supply pipe 8 is provided with a hot water supply amount sensor 9. Water supplied to the water supply pipe 8 from a water supply or the like corresponds to an example of water supplied from outside the hot water heater 1. The hot water outlet pipe 10 is connected to an outlet of the first heat exchanger 7. The hot water outlet pipe 10 is a pipe that flows hot water heated by the first heat exchanger 7. The hot water outlet pipe 10 forms a path that sends hot water heated by the first heat exchanger 7 to the outside of the appliance. In the example of FIG. 1, a hot water tap 11 is provided on a pipe connected to a hot water outlet pipe 10 outside the appliance.

[0017] A bypass pipe 12 is connected between the water supply pipe 8 and the hot water outlet pipe 10 so as to bypass the first heat exchanger 7. A bypass control valve 13 is provided in the bypass pipe 12. The bypass control valve 13 is a valve for controlling the flow rate to the bypass pipe 12. A hot water inner body thermistor 14 is provided upstream of the connection part of the bypass pipe 12 in the hot water outlet pipe 10. The hot water inner body thermistor 14 detects the hot water temperature from the outlet of the first heat exchanger 7. A hot water outlet thermistor 15 is provided downstream of the connection part of the bypass pipe 12. The hot water outlet thermistor 15 detects the outlet temperature of the hot water from the bypass pipe 12 after it has been mixed with water.

[0018] The hot water supply circuit 2 further includes a gas pipe, a main gas solenoid valve 17, a hot water supply gas proportional valve 18, and a hot water supply switching solenoid valve 19. The gas pipe 16 is a pipe through which gas supplied from outside the hot water heater 1 via a gas inlet passes, and forms a path for supplying gas to the hot water supply burner 6. The main gas solenoid valve 17 is provided upstream of the gas pipe 16, and the hot water supply gas proportional valve 18 is provided downstream of the main gas solenoid valve 17. The gas pipe 16 branches downstream of the hot water supply gas proportional valve 18, and branch pipes to each hot water supply burner 6 are provided. Each branch pipe is provided with a hot water supply switching solenoid valve 19.

[0019] The hot water supply circuit 2 further includes a hot water supply fan 20, an igniter 21 for ignition, an ignition electrode 22, and a hot water supply frame rod 23. The hot water supply fan 20 is provided below the hot water supply combustion chamber 5, and supplies air for combustion to each hot water supply burner 6.

[0020] The heating circuit 3 includes a heating combustion chamber 30 and a heat medium circulation path 48. The heating combustion chamber 30 includes a plurality of heating burners 31 and a second heat exchanger 32 that heats the heat medium passing through the inside by the combustion exhaust of the heating burners 31. The second heat exchanger 32 functions as a heating side heat exchanger. In this embodiment, the heat medium is hot water. However, the heat medium may be a fluid other than hot water. The heating circuit 3 is a circuit that heats the heat medium by the second heat exchanger 32 and supplies the heat medium to the heating terminal via the heat medium circulation path 48. Each of the plurality of heating burners 31 is configured as a gas burner that burns gas, and corresponds to an example of the second burner. The second heat exchanger 32 corresponds to an example of the second heat exchanger, and is configured to be heated by the exhaust generated by the second burner. In the example of FIG. 1, a high-temperature radiator 34 and a low-temperature radiator 39 are provided as examples of the heating terminal.

[0021] The heat medium circulation path 48 is a path for circulating the heat medium through the second heat exchanger 32, and forms a flow path of the heat medium. The heat medium circulation path 48 includes the heating high temperature forward pipe 33, the heating return pipe 35, the heating low temperature forward pipe 38, and the heating return pipe 35. When the high temperature radiator 34 is connected as shown in FIG. 1, the heat medium circulation path 48 configures a flow path for circulating the heat medium through the heating high temperature forward pipe 33, the high temperature radiator 34, and the heating return pipe 35. When the low temperature radiator 39 is connected as shown in FIG. 1, the heat medium circulation path 48 forms a flow path for circulating the heat medium through the heating low temperature forward pipe 38, the low temperature radiator 39, and the heating return pipe 35.

[0022] 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 33 is connected to the outlet of the second heat exchanger 32 and is connected to a high-temperature radiator 34 as a heating terminal outside the appliance, and a heating return pipe 35 is connected to the high-temperature radiator 34 outside the appliance and is connected to an inlet of the second heat exchanger 32. The heating return pipe 35 is provided with an expansion tank 36 and a heating circulation pump 37, and a heating low-temperature forward pipe 38 is connected to the downstream side of the heating circulation pump 37 and is connected to a low-temperature radiator 39 as a heating terminal outside the appliance. The downstream side of the low-temperature radiator 39 is connected to the heating return pipe 35 downstream of the high-temperature radiator 34. Here, the high-temperature radiator 34 serves as a heating blower that blows hot air into the bathroom or the dressing room, and the low-temperature radiator 39 serves as a floor heater for the dressing room. The heating high temperature thermistor 40 is provided in the heating high temperature outgoing pipe 33 on the outlet side of the second heat exchanger 32. The heating low temperature thermistor 41 is provided in the expansion tank .

[0023] The heating circuit 3 further includes a gas branch pipe 42, a heating gas proportional valve 43, heating switching solenoid valves 44, 44, a heating fan 45, an ignition electrode 46, and a heating flame rod 47. The gas branch pipe 42 is provided so as to branch off from the gas pipe 16 to the heating circuit 3 side, and the gas branch pipe 42 is provided with a heating gas proportional valve 43 from the upstream side, and heating switching solenoid valves 44, 44 for each branch pipe to each heating burner 31. The heating fan 45 is provided below the heating combustion chamber 30 so as to supply combustion air to each heating burner 31.

[0024] In the heating circuit 3, the heating circulation pump 37 operates to circulate the heat medium (e.g., hot water) heated in the second heat exchanger 32 through the heat medium circulation path 48. Specifically, the heat medium heated in the second heat exchanger 32 circulates through the heating high-temperature forward pipe 33, the high-temperature radiator 34, and the heating return pipe 35, and also circulates through the heating low-temperature forward pipe 38, the low-temperature radiator 39, and the heating return pipe 35. The heat medium (e.g., hot water) is supplied to the high-temperature radiator 34 by the operation of the built-in thermal valve. Specifically, the heat medium is supplied when the built-in thermal valve built into the high-temperature radiator 34 is in an open state. The heat medium is supplied to the low-temperature radiator 39 by the operation of the thermal valve in the appliance. Specifically, the heat medium is supplied to the low-temperature radiator 39 when the thermal valve built into the hot water heater 1 is in an open state.

[0025] The bath heating pipe 51 is provided in a configuration that branches off from the heating high-temperature forward pipe 33. The bath heating pipe 51 corresponds to an example of a branch path. The bath heating pipe 51 branches off from a position downstream of the second heat exchanger 32 in the heat medium circulation path 48 (more specifically, a position between the second heat exchanger 32 and the high-temperature radiator 34 in the heating high-temperature forward pipe 33) and forms a flow path that guides 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 33 and the heating return pipe 35. The downstream end of the bath heating pipe 51 is connected to a position between the high-temperature radiator 34 and the expansion tank 36 in the heating return pipe 35. When the control valve 58 is in an open state, a part of the heat medium that flows through the second heat exchanger 32 and enters the heating high-temperature forward pipe 33 flows into the bath heating pipe 51, and circulates from the bath heating pipe 51 to the heating return pipe 35.

[0026] The control valve 58 is a valve provided in the bath heating pipe 51 on the upstream side of the bath heat exchanger 50. The control valve 58 is configured to open and close the bath heating pipe 51, and is configured to switch between a closed state (fully closed state) in which the control valve 58 blocks water passing through the bath heating pipe 51, and an open state (fully open state) in which the control valve 58 allows water to pass through the bath heating pipe 51. In other words, when the control valve 58 is in the open state (fully open state), the heat medium upstream of the control valve 58 is allowed to pass through the control valve 58 and flow through the portion of the pipe 50A in the bath heating pipe 51, and when the control valve 58 is in the closed state (fully closed state), the heat medium upstream of the control valve 58 is blocked from passing through the control valve 58, and the heat medium does not flow from the upstream side of the control valve 58 to the "portion of the pipe 50A in the bath heating pipe 51."

[0027] The control valve 58 has a switch. This switch is configured as, for example, a limit switch, and goes into a first state in which a predetermined first signal (for example, an ON signal) is output when the control valve 58 is in a predetermined open state (specifically, for example, a fully open state in which the control valve 58 is fully open), and goes into 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 a fully closed state in which it is shut off. Various types of switches can be used as the switch, as long as they can transmit a first signal when the control valve 58 is in the predetermined open state, and output a second signal different from the first signal when the control valve 58 is in a fully closed state.

[0028] The bath circuit 4 comprises a bath circulation path 63 and a bath heat exchanger 50. The bath circulation path 63 is a flow path configured to circulate hot and cold water drawn from an external bathtub 52 and introduce it into the bathtub 52. The bath heat exchanger 50 is configured as a liquid-liquid heat exchanger that exchanges heat between the heat medium flowing through the bath heating pipe 51 and the hot and cold water flowing through the bath circulation path 63. The bath heat exchanger 50 is configured such that when the temperature of the heat medium flowing through the bath heating pipe 51 is higher than the temperature of the hot and cold water flowing through the pipe 50A, the heat of the heat medium flowing through the bath heating pipe 51 is transferred to the hot and cold water flowing through the pipe 50A, thereby heating the hot and cold water.

[0029] The bath heat exchanger 50 is provided with a pipe 50A that is a part of the bath circulation path 63, and the bath heating pipe 51 is arranged in the pipe 50A. The bath circulation path 63 is composed of the pipe 50A, the bath supply pipe 53, and the bath return pipe 54. When the bath circulation pump 55 is operating, the bath circulation path 63 functions as a flow path that draws hot water from the bathtub 52 installed outside the hot water heater 1, and functions as a flow path that circulates the drawn hot water and introduces it into the bathtub 52. The bath return pipe 54 is provided with the bath circulation pump 55, a pressure sensor 56, and a water flow switch 57. The bath return pipe 54 is provided between the bathtub 52 outside the device and the pipe 50A, and forms a flow path that flows hot water from the bathtub 52 to the pipe 50A when the bath circulation pump 55 is operating. The bath supply pipe 53 is provided between the pipe 50A and the bathtub 52, and forms a flow path that allows hot and cold water to flow from the pipe 50A to the bathtub 52 when the bath circulation pump 55 is operating. The pipe 50A forms a flow path that allows hot and cold water to flow from the bath return pipe 54 side to the bath supply pipe 53 side when the bath circulation pump 55 is operating. A bath supply thermistor 64 is provided in the bath supply pipe 53. A bath return thermistor 65 is provided in the bath return pipe 54.

[0030] A drop pipe 59 is connected to the bath return pipe 54, branching off from the hot water outlet pipe 10. The drop pipe 59 is provided with hot water supply solenoid valves 60, 60, a drop water level sensor 61, check valves 62, 62, etc. When the hot water supply circuit 2 is in operation, the hot water supply solenoid valves 60, 60 provided in the drop pipe 59 are opened, so that hot water heated in the hot water supply circuit 2 is supplied to the bathtub 52 through the drop pipe 59.

[0031] The hot water heater 1 further includes a control device 70, a hot water remote control 71, a bath remote control 72, and a room temperature thermistor 73. The control device 70 functions as a controller that performs various controls. The room temperature thermistor 73 is provided, for example, in a changing room as a temperature detection means that detects the temperature in the changing room.

[0032] 2. Operation of hot water heater 1 (Normal hot water supply operation) When the hot water tap 11 provided on the hot water outlet pipe 10 is opened to allow water to flow into the appliance and the hot water volume sensor 9 outputs a signal indicating water flow, the control device 70 rotates the hot water fan 20 for a predetermined time to discharge the combustion exhaust gas stored in the hot water combustion chamber 5 (pre-purge). After that, the control device 70 opens the main gas solenoid valve 17 of the gas pipe 16 and each hot water switching solenoid valve 19, opens the hot water gas proportional valve 18 at a predetermined opening degree, controls to supply gas to each hot water burner 6, and operates the igniter 21 to ignite the hot water burner 6. With this control, a hot water outlet operation is performed so that the water passing through the first heat exchanger 7 is heated and flows into the hot water outlet pipe 10, and the heated hot water is discharged from the hot water tap 11.

[0033] During the above-mentioned hot water discharging operation, the control device 70 monitors the hot water outlet temperature detected by the hot water outlet thermistor 15 installed in the hot water outlet pipe 10, and controls the opening and closing of the hot water switching solenoid valve 19 and adjusts the opening of the hot water gas proportional valve 18 so that the hot water outlet temperature becomes the set temperature instructed by the hot water remote control 71 or the bath remote control 72, while continuously changing the amount of air by controlling the rotation speed of the hot water fan 20. If the hot water tap 11 is closed during the above-mentioned hot water discharging operation and the signal output by the hot water amount sensor 9 indicates a water stop state, the control device 70 closes the main gas solenoid valve 17 and the hot water switching solenoid valve 19 to extinguish the hot water burner 6, and rotates the hot water fan 20 for a predetermined time to perform post-purge.

[0034] (Automatic water filling operation) The control device 70 can perform control to automatically fill the bathtub 52 with hot water. For example, when a hot water filling switch provided on the hot water supply remote control 71 or the bath remote control 72 is pressed, the control device 70 sets the outlet hot water temperature to the target temperature (e.g., 40°C) set by the hot water supply remote control 71 or the bath remote control 72, and starts filling the bath with hot water. 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-passing state, and burns the hot water supply burner 6, so that the heated hot water flows into the hot water outlet pipe 10. The hot water that flows through the hot water outlet pipe 10 in this way is supplied to the bathtub 52 through the drop pipe 59 and the bath return pipe 54.

[0035] After starting to supply hot water to bathtub 52 in this way, control device 70 monitors whether the amount of water detected by drop water volume sensor 61 installed in drop pipe 59 (total amount of water since the start of automatic filling) has reached the set amount, and if it confirms that it has reached that amount, it closes hot water supply solenoid valve 60 to stop water flow and extinguishes hot water supply burner 6 to end filling the bath. Then, control device 70 operates bath circulation pump 55 to circulate the hot water in bathtub 52 within bath circuit 4. When filling the bath is finished, control device 70 notifies the completion of filling the bath via hot water supply remote control 71 or bath remote control 72.

[0036] (Automatic reheating operation) The control device 70 can automatically control the reheating (boiling) of water stored in the bathtub 52. For example, when a reheating switch provided on the hot water supply remote control 71 or the bath remote control 72 is pressed, the control device 70 sets the reheating temperature to the target temperature (for example, 40°C) set by the hot water supply remote control 71 or the bath remote control 72 and starts the reheating. Specifically, the control device 70 ignites the heating burner 31, opens the control valve 58, operates the bath circulation pump 55, and performs reheating by circulating the hot water in the bathtub 52 and heating it with the bath heat exchanger 50. After starting such reheating, the control device 70 monitors whether the hot water temperature detected by the bath return thermistor 65 has reached the target temperature, and when it is confirmed that the temperature has been reached, turns off the heating burner 31, stops the bath circulation pump 55, and ends the reheating. When the control device 70 ends the reheating, it notifies the end of the reheating by the hot water supply remote control 71 or the bath remote control 72.

[0037] (judgment action) The control device 70 that controls the opening and closing of the control valve 58 may perform judgment control. The judgment control is a control that performs a confirmation operation to set the control valve 58 to the above-mentioned predetermined open state and fully closed state one or more times when the heating circuit 3 is in a predetermined non-operating state, and judges whether or not the above-mentioned switch has switched to the first state and the second state during such a confirmation operation. In a representative example described below, the "predetermined non-operating state" is a state before the operation of the heating circuit 3 starts (specifically, a state before the heating burner 31 is ignited) after the conditions for operating the heating circuit 3 (specifically, a condition for igniting the heating burner 31) are established.

[0038] The control device 70 performs the above-mentioned determination control when a predetermined determination start condition is satisfied. Specifically, the control device 70 can perform heating control of the heating circuit 3, for example, in a flow as shown in FIG. 2, and can perform the above-mentioned determination control during this heating control process. In the example of FIG. 2, when the operation start condition of the hot water heater 1 is satisfied (for example, when the hot water heater 1 is powered on, or when power supply to the control device 70 is started), the control device 70 starts the control of FIG. 2, and first, in step S1, it determines whether or not the heating condition of the heating circuit 3 is satisfied. The heating condition of the heating circuit 3 is specifically a condition for igniting the heating burner 31, and may be, for example, a predetermined switch (for example, a reheating switch for instructing automatic reheating operation or a switch for instructing the operation of the high-temperature radiator 34) provided on the hot water remote control 71 or the bath remote control 72 is pressed, or may be another condition.

[0039] If the control device 70 determines in step S1 that the above heating conditions are not met, it proceeds to No in step S1 and maintains a standby state without igniting the heating burner 31. Note that, in a standby state without igniting the heating burner 31, the control device 70 maintains the control valve 58 in a fully closed state, and in the fully closed state, it blocks the passage of the heat medium through the control valve 58 from one side (the heating high-temperature outgoing pipe 33 side) to the other side (the bath heat exchanger 50 side). If the control device 70 determines in step S1 that the above heating conditions are met, it proceeds to Yes in step S1 and performs judgment control in step S2.

[0040] When performing the judgment control in step S2, the control device 70 performs a confirmation operation of putting the control valve 58 in a fully open state and a fully closed state a predetermined number of times (e.g., three times). When the switch provided in the control valve 58 is normal, a first signal is output from the switch when the control valve 58 is put in a fully open state, and a second signal is output from the switch when the control valve 58 is put in a fully closed state. When performing the confirmation operation of putting the control valve 58 in a fully open state and a fully closed state a predetermined number of times (e.g., three times) in step S2, the control device 70 judges whether or not the switch has reached a first state in which the switch outputs a first signal (e.g., an ON signal) when the control valve 58 is put in a fully open state during the confirmation operation, and judges whether or not the switch has reached a second state in which the switch outputs a second signal (e.g., an OFF signal) when the control valve 58 is put in a fully closed state during the confirmation operation. The control device 70 determines that the control valve 58 is normal on the condition that the switch is in the first state when the control valve 58 is in an open state during the checking operation, and the switch is in the second state when the control valve 58 is in a closed state during the checking operation. For example, the control device 70 determines that the control valve 58 is normal when the switch is in the first state in all of the fully open states during the checking operation and the switch is in the second state in all of the fully closed states during the checking operation. In this example, the control device 70 determines that the control valve 58 is abnormal when the switch is not in the first state (for example, when it is in the second state) in any of the fully open states during the checking operation, or when the switch is not in the second state (for example, when it is in the first state) in any of the fully closed states during the checking operation. When the control device 70 determines that the control valve 58 is abnormal, it performs a notification operation. The alarm operation may be an alarm operation in which a sound (e.g., a buzzer sound or an error message) is emitted from a sound generating device (buzzer, speaker, etc.) not shown in the figure provided in the hot water heater 1 to notify of an abnormality, an alarm operation in which an error code or an error message is displayed on a display unit not shown in the figure provided in the hot water heater 1, or an alarm operation in which error information is transmitted via wired or wireless communication to an external device provided outside the hot water heater 1.If the control device 70 determines in the above-mentioned determination control that the control valve 58 is abnormal, the control device 70 may not perform the processes of steps S3 to S5 described below.

[0041] When reporting an abnormality in step S2, the specific details of the abnormality of the control valve 58 may be reported. For example, when the control device 70 performs the above-mentioned checking operation and attempts to control the control valve 58 to the fully open state by issuing an instruction to the control valve 58 to fully open the control valve 58 and the control valve 58 does not fully open, the control device 70 may report, by voice, display, communication, etc., that the fully opening operation of the control valve 58 is abnormal. Alternatively, when the control device 70 performs the above-mentioned checking operation and attempts to control the control valve 58 to the fully closed state by issuing an instruction to the control valve 58 to fully close the control valve 58 and the control valve 58 does not fully close, the control device 70 may report, by voice, display, communication, etc., that the fully closing operation of the control valve 58 is abnormal.

[0042] After performing the judgment control in step S2, the control device 70 heats the heating circuit 3 in step S3. When the control device 70 heats the heating circuit 3 in step S3, it ignites the heating burner 31 and controls each valve provided in the heating circuit 3. When the control device 70 heats the heating circuit 3 in step S3, the route through which the heat medium flows depends on the content of the heating conditions. For example, when the heating conditions established in step S1 are conditions for starting the automatic reheating operation, as described above, it ignites the heating burner 31, opens the control valve 58 (for example, fully opens), and drives the heating circulation pump 37 to flow the heat medium through the bath heating pipe 51 (branch path). When the heating conditions established in step S1 are conditions for heating the high-temperature radiator 34 without performing reheating, the control device 70 fully closes the control valve 58 and drives the heating circulation pump 37 to cause the heat medium to flow through the heating high-temperature supply piping 33 and the high-temperature radiator 34.

[0043] After step S3, the control device 70 determines whether the heating end condition of the heating circuit 3 is satisfied in step S4, and if it determines that the heating end condition is not satisfied in step S4, it proceeds to No in step S4 and maintains the heating state of the heating circuit in step S3. If the control device 70 determines that the heating end condition of the heating circuit 3 is satisfied in step S4, it proceeds to Yes in step S4 and ends the heating of the heating circuit 3 in step S5.

[0044] 3.Examples of effects The hot water heater 1 can open and close the bath heating pipe 51 (branch path) branching off from a position downstream of the heat exchanger in the heating circuit 3 by using a control valve 58. In such a hot water heater 1, an abnormality in the opening and closing of the control valve 58 can be determined. Specifically, if a switch (limit switch) provided in the control valve 58 changes from the second state to the first state and then returns to the second state, it can be confirmed that the control valve 58 has changed from the fully closed state to the fully open state once and then changed back to the fully closed state, so that it can be confirmed that the control valve 58 operates normally. On the other hand, if the switch does not change to the first state when the control valve 58 is instructed to be in the fully open state, or if the switch does not change to the second state when the control valve 58 is instructed to return to the fully closed state, there is a high possibility that the opening and closing operation of the control valve 58 is abnormal, and in such a case, a user can be notified by an alarm operation.

[0045] Each time the hot water heater 1 heats the heating circuit 3, it can determine whether or not there is an abnormality in the control valve 58 before heating the heating circuit 3. Therefore, the hot water heater 1 can reduce the risk that an abnormality in the control valve 58 will be left undiscovered.

[0046] <Other embodiments> The present invention is not limited to the embodiments described above and in the drawings. For example, the features of the above or later described embodiments can be combined in any combination within a range that does not contradict. Furthermore, any feature of the above or later described embodiments can be omitted unless it is clearly stated as essential. Furthermore, the above described embodiments may be modified as follows.

[0047] In the example of FIG. 1, high-temperature radiator 34 and low-temperature radiator 39 are connected to the heating circuit as heating terminals, but only one of them may be connected, or more than these may be connected.

[0048] In the example of Figure 1, a first heat exchanger is provided in the hot water circuit and a second heat exchanger is provided in the heating circuit, but these heat exchangers may also be latent heat recovery type heat exchangers equipped with a primary heat exchanger and a secondary heat exchanger.

[0049] In the example of Figure 1, the first heat exchanger 7 and the second heat exchanger 32 are positioned separately, and the multiple hot water burners 6 and the multiple heating burners 31 are positioned separately, but these may be placed in a common container (e.g., a metal can body) and the container may be divided into a space that houses the first heat exchanger and the hot water burners and a space that houses the second heat exchanger and the heating burners.

[0050] In the above embodiment, the predetermined non-operating state is a state after the condition for operating the heating circuit 3 is satisfied and before the operation of the heating circuit 3 starts, but is not limited to this example. The predetermined non-operating state may be, for example, a period from when the heating burner 31 is turned off in step S5 until the next time Yes is determined in step S1 (i.e., a period until the next heating condition of the heating circuit 3 is satisfied).

[0051] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is not limited to the embodiments disclosed herein, and is intended to include all modifications within the scope indicated by the claims or within the scope equivalent to the claims. [Explanation of symbols]

[0052] 1: Hot water heater 2: Hot water circuit 3: Heating circuit 4: Bath circuit 6: Hot water burner (first burner) 7: 1st heat exchanger 31: Heating burner (second burner) 32:Second heat exchanger 34: High temperature radiator (heating terminal) 39: Low temperature radiator (heating terminal) 40: Heating high temperature thermistor 41: Heating low temperature thermistor 48: Heat medium circulation path 50: Bath heat exchanger 51: Bath heating pipe (branch) 52: Bathtub (external bathtub) 58: Control valve 63: Bath Circulation 70: Controller (control device)

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 bath circuit having a bath circulation path that circulates hot and cold water drawn from an external bathtub and introduces it into the external bathtub; A liquid-liquid heat exchanger that exchanges heat with the hot water flowing through the bath circulation path; a branch path that branches off from a position downstream of the second heat exchanger in the heat medium circulation path and guides the heat medium that has flowed through the heat medium circulation path to the liquid-liquid heat exchanger; a control valve that opens and closes the branch passage; a switch that is in a first state when the control valve is in an open state and in a second state when the control valve is in a closed state; A control device for controlling the control valve; Equipped with The control device performs a confirmation operation to switch the control valve between the open state and the closed state one or more times when the heating circuit is in a predetermined non-operating state, and performs a determination control to determine whether or not the switch has switched between the first state and the second state during the confirmation operation. Hot water heater.

2. The predetermined non-operating state is a state after a condition for operating the heating circuit is satisfied and before the operation of the heating circuit starts. The hot water heater according to claim 1.

Images