Hot water supply heater

Abstract

To suppress an unintended valve opening operation of a selector valve due to short circuit between a plurality of paths connected to a plurality of terminals disposed adjacent to each other.SOLUTION: A microcomputer 70A of a hot water supply heater 1 includes: a first terminal P1 connected to a first selector valve V1 via a first path out of a plurality of selector valves 39G; and a second terminal P2 disposed adjacent to the first terminal P1 and connected to a second selector valve V2 via a second path out of the plurality of selector valves 39G. When outputting a high-level output signal via the first terminal P1, the microcomputer 70A allows input of an input signal via the second terminal P2, and detects presence / absence of short circuit between the first path and the second path on the basis of the input signal.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a hot water supply and heating machine.

Background Art

[0002] Patent Document 1 describes a hot water supply device. This hot water supply device includes a heat source machine having a controller and a connection terminal unit. The connection terminal unit has a plurality of connection terminals. The plurality of connection terminals are arranged adjacent to each other in a row, and each connection terminal is connected to a communication cable of a bathroom heater or a plurality of different floor heaters, respectively.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a configuration where a plurality of connection terminals of a connection terminal unit are arranged adjacent to each other, if a short circuit occurs between communication cables connected to adjacent connection terminals or between connection terminals due to some factor, when a signal to turn on the floor heater is output, a signal to turn on other floor heaters or the like is output via the short-circuited path and adjacent communication cables or the like, and there is a risk of operating unintended floor heaters or the like. In particular, when the supply of hot water as a heat medium to a floor heater or the like is performed by opening and closing a thermostatic valve, generally, the thermostatic valve does not have a function of detecting its own opening and closing. Therefore, even if hot water as a heat medium is supplied to an unintended heater or the like by being erroneously opened, it cannot be noticed immediately, and there is a problem that the valve opening state continues.

[0005] One object of the present disclosure is to suppress an unintended valve opening operation of a switching valve due to a short circuit between a plurality of paths connected to a plurality of adjacent terminals.

Means for Solving the Problems

[0006] One of the disclosed water heaters is configured to supply a heat medium to a plurality of heat dissipation terminals and is configured to control each switching valve provided corresponding to the terminal flow path of each of the heat dissipation terminals, and the state of the switching valve is changed to a first state that permits the supply of the heat medium to the terminal flow path corresponding to the switching valve and a second state that shuts off the supply. A water heater that switches between the two states, A water supply circuit that heats water supplied from the outside to supply hot water, A heat medium circulation path that serves as a path for circulating the heat medium together with the terminal flow path, a gas burner that burns gas, and a heat exchanger that heats the heat medium flowing through the heat medium circulation path by the combustion exhaust generated by the gas burner. And a heating circuit that supplies the heat medium heated by the heat exchanger to the terminal flow path via the heat medium circulation path, A control unit that controls the opening and closing operations of the plurality of switching valves by outputting high-level and low-level signals to each of the plurality of terminals, Comprising, Among the plurality of terminals, the first terminal is a terminal that outputs a signal instructing an opening operation and a signal instructing a closing operation to the first switching valve among the plurality of switching valves via a first path, The second terminal among the plurality of terminals is a terminal adjacent to the first terminal and outputs a signal instructing an opening operation and a signal instructing a closing operation to the second switching valve among the plurality of switching valves via a second path. It is a terminal, The control unit monitors an input signal input to the second terminal in an output state in which a high-level signal is output to the first terminal, and based on the input signal in the output state, the first path and the second path are monitored. Detect a short circuit between

Effect of the Invention

[0007] ​

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0009] Each of the following [1] to [5] is an example of a hot water heater included in the present disclosure.

[0010] 〔1〕 A hot water heater configured to supply a heat medium to a plurality of heat dissipation terminals and to control each switching valve provided corresponding to the terminal flow path of each heat dissipation terminal, and configured to switch the state of the switching valve between a first state that permits the supply of the heat medium to the terminal flow path corresponding to the switching valve and a second state that shuts off the supply, comprising: A hot water supply circuit that heats water supplied from the outside and supplies hot water; A heat medium circulation path that serves as a path for circulating the heat medium together with the terminal flow path, a gas burner that burns gas, and a heat exchanger that heats the heat medium flowing through the heat medium circulation path by combustion exhaust generated by combustion in the gas burner, and a heating circuit that supplies the heat medium heated by the heat exchanger to the terminal flow path via the heat medium circulation path; A control unit that controls the opening and closing operations of the plurality of switching valves by outputting high-level and low-level signals to each of the plurality of terminals; and Among the plurality of terminals, the first terminal is a terminal that outputs a signal for instructing an open valve operation and a signal for instructing a close valve operation to a first switching valve among the plurality of switching valves via a first path. Among the plurality of terminals, the second terminal is a terminal adjacent to the first terminal and outputs a signal for instructing an open valve operation and a signal for instructing a close valve operation to a second switching valve among the plurality of switching valves via a second path. The control unit monitors an input signal input to the second terminal in an output state where a high-level signal is output to the first terminal, and detects a short circuit between the first path and the second path based on the input signal in the output state. A water heater.

[0011] When a short circuit occurs between the first path between the first terminal and the first switching valve and the second path between the second terminal and the second switching valve for some reason, when a high-level output signal is output via the first terminal, not only the first switching valve but also a high-level output signal is output to the second switching valve via the short circuit path, and there is a concern that an unintended malfunction may occur. In this regard, the water heater of the above [1] operates to monitor a signal input to the second terminal arranged adjacent to the first terminal in a state where a high-level output signal is output from the control unit via the first terminal. During this monitoring period, if a low-level signal is input to the second terminal, it is highly likely that a situation where the high-level signal output to the first terminal is input to the second terminal due to a short circuit has not occurred. On the other hand, if a low-level signal is not input to the second terminal in the output state of the output signal during the above monitoring period and a relatively high voltage is input, it is highly likely that a short circuit has occurred between the first path and the second path. Therefore, if the control unit detects a short circuit between the first path and the second path based on the input signal in the above output state, the short circuit can be detected more accurately.

[0012] 〔2〕After monitoring the input signal in the output state for a predetermined time, the control unit switches to a state of outputting a signal for instructing an open valve operation or a signal for instructing a close valve operation to the second terminal. The hot water heater according to 〔1〕.

[0013] Since the hot water heater of 〔2〕 above can be switched to output a signal for instructing an open valve operation or a signal for instructing a close valve operation to the second terminal after temporarily functioning the second terminal as an input terminal to perform a short - circuit detection operation, the burden of monitoring the second terminal over a long period of time can be reduced, and the second terminal can function as an output terminal more quickly.

[0014] 〔3〕The control unit detects the short - circuit when changing the opening and closing state of the first switching valve. The hot water heater according to 〔1〕 or 〔2〕.

[0015] The hot water heater of 〔3〕 above can detect a short - circuit at an early stage after the opening and closing state of the first switching valve changes, before the second switching valve performs an unintended operation due to the short - circuit and the influence becomes greater.

[0016] 〔4〕It has a notification unit that notifies error information indicating the short - circuit when the short - circuit is detected. The hot water heater according to any one of 〔1〕 to 〔3〕.

[0017] The hot water heater of 〔4〕 above can notify the outside of the hot water heater of the occurrence of a short - circuit at an early stage.

[0018] 〔5〕The switching valve is a thermostatic valve that expands an expansion body with the heat of a heating element to open the valve. The hot water heater according to any one of 〔1〕 to 〔4〕.

[0019] <First Embodiment> The following description relates to the hot water heater 1 according to the first embodiment. 1. Overall configuration of the hot water heater 1 FIG. 1 is a schematic circuit diagram of the water heater and heater 1. The water heater and heater 1 mainly includes a hot water supply circuit 2, a heating circuit 3, a bathtub circuit 4, etc., and is a device capable of performing hot water supply operation, automatic water filling operation, reheating operation, heating operation, etc.

[0020] The water heater and heater 1 is provided with a housing 1A configured as a metal casing inside the housing, and a first combustion system part 5 and a second combustion system part 6 are configured inside the housing 1A. The housing 1A is configured as, for example, a metal can body or a metal box body, and is configured to accommodate a hot water supply burner 8A, a heating burner 33A, a hot water supply side heat exchanger 7, a heating side heat exchanger 32, etc. The first combustion system part 5 is a combustion system that performs gas combustion and water heating when the hot water supply 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 reheating operation.

[0021] The hot water supply circuit 2 is a circuit that heats the water supplied from the outside of the water heater and heater 1 by the hot water supply side heat exchanger 7 and supplies hot water. The hot water supply circuit 2 includes the first combustion system part 5, and specifically includes a plurality of hot water supply burners 8A and the hot water supply side heat exchanger 7. An ignition plug 85 and a flame sensor 86 are provided above the hot water supply burner 8A. The ignition plug 85 ignites the combustion gas by generating a spark discharge according to an input signal from the control device 70, and the flame generated by the combustion is detected by the flame sensor 86. The first combustion system part 5 is provided with a hot water supply combustion chamber 5A, and a hot water supply side burner unit 8 and a hot water supply side heat exchanger 7 are provided in the hot water supply combustion chamber 5A. The hot water supply 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 supply burners 8A. Each of the plurality of hot water supply burners 8A is configured as a gas burner that burns gas.

[0022] The hot water supply side heat exchanger 7 is a heat exchanger heated by the exhaust gas generated by the hot water supply burner 8A. The hot water supply side heat exchanger 7 includes a first hot water supply side heat exchanger 7A and a second hot water supply side heat exchanger 7B. The first hot water supply side heat exchanger 7A has a plurality of fins 7Z. The first combustion system section 5 is provided with the first hot water supply side heat exchanger 7A above a plurality of hot water supply burners 8A, and the second hot water supply side heat exchanger 7B is provided above the first hot water supply side heat exchanger 7A. A pipeline 7C is connected between the downstream end of the second hot water supply side heat exchanger 7B and the upstream end of the first hot water supply side heat exchanger 7A, and the hot water flowing through the second hot water supply side heat exchanger 7B flows through the pipeline 7C to the first hot water supply side heat exchanger 7A. The hot water supply side heat exchanger 7 heats the water passing through the inside by the exhaust gas (combustion exhaust gas) generated by burning gas with a plurality of hot water supply burners 8A. The first hot water supply side heat exchanger 7A recovers sensible heat from the combustion exhaust gas discharged from the hot water supply side burner unit 8, and the second hot water supply side heat exchanger 7B recovers latent heat from the combustion exhaust gas discharged from the hot water supply side burner unit 8.

[0023] The hot water supply circuit 2 further includes a water supply pipe 11, a control valve 13A, a water flow 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 outlet thermistor), and the like. 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 pipeline 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 flow 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 by control. 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 pipeline through which the hot water heated by the hot water supply side heat exchanger 7 flows. 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.

[0024] 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 by control. 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 heat exchanger 7A on the hot water supply side. A thermistor 15B is provided downstream of the connection portion of the bypass pipe 12. The thermistor 15B detects the hot water temperature after mixing of the water from the bypass pipe 12. 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 a control device 70 described later.

[0025] 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 solenoid valve 19. The gas pipe 16 is a pipe through which gas supplied from outside the hot water supply and heating machine 1 through the gas inlet passes, and forms a path for supplying gas to the hot water supply burner 8A. A main gas solenoid valve 17 is provided upstream of the gas pipe 16, and a gas proportional valve 18 is provided downstream of the main gas solenoid valve 17. The downstream side of the gas proportional valve 18 (hot water supply gas proportional valve) in the gas pipe 16 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. A solenoid valve 19 is provided in each branch pipe 16A. The solenoid 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 the fuel gas to each of the burner blocks 9A, 9B, 9C are individually switched by each solenoid valve 19. By switching the solenoid 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.

[0026] The hot water supply circuit 2 further includes a fan 20. 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. The fan 20 is provided below the hot water supply combustion chamber 5A. 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 90. Near the fan 20, a current sensor 75 that detects the drive current of the fan 20 and a rotation speed sensor 76 that detects the rotation speed (rotational speed) of the fan 20 are provided. A signal corresponding to the drive current of the fan 20 detected by the current sensor 75 and a signal corresponding to the rotation speed of the fan 20 detected by the rotation speed sensor 76 are output to the control device 70. The hot water supply circuit 2 is also provided with an igniter for ignition, an ignition electrode, a hot water supply frame rod, etc.

[0027] The bathtub circuit 4 includes a bathtub circulation path 63 and a bathtub heat exchanger 50. The bathtub circulation path 63 forms a flow path configured to circulate the hot water derived from an external bathtub 52 and introduce it into the bathtub 52. The bathtub heat exchanger 50 is configured as a liquid-liquid heat exchanger that performs heat exchange between the heat medium flowing through the bathtub heating pipe 51 and the hot water flowing through the bathtub circulation path 63.

[0028] The bathtub heat exchanger 50 is provided with a pipe 50A that forms part of the bathtub circulation path 63, and the bathtub heating pipe 51 is arranged within the pipe 50A. The bathtub circulation path 63 is composed of 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 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 with a flow rate equal to or greater than a predetermined value is flowing in 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.

[0029] The drain pipe 59 is connected to the bathtub return pipe 54 in a configuration branched from the hot water outlet pipe 10. The drain pipe 59 communicates with the bathtub return pipe 54. The drain pipe 59 is provided with a hot water supply solenoid valve 60, a drain water volume sensor 61, a plurality of check valves 62, etc. When the hot water supply solenoid valve 60 provided in the drain 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 drain pipe 59.

[0030] The heating circuit 3 is a circuit that can heat the heat medium by the heating-side heat exchanger 32 and supply the heat medium to the heating terminal (heat dissipation terminal) via the heat medium circulation path 48. In the present embodiment, the heat medium is, for example, hot water. Note that, as the heat medium, a fluid other than hot water may be used. The heating circuit 3 includes a second combustion system unit 6 and a heat medium circulation path 48. In the second combustion system unit 6, a heating combustion chamber 6A is provided, and a heating-side burner unit 33 and a heating-side heat exchanger 32 are provided in the heating combustion chamber 6A. The heating combustion chamber 6A is partitioned by a partition member 80 from the hot water supply combustion chamber 5A in the housing 1A, and a temperature sensor 82 for detecting the temperature of the heating combustion chamber 6A is provided on the partition member 80.

[0031] 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 is configured as a gas burner that burns gas. An ignition plug 85 and a flame sensor 86 are provided above the heating burner 33A.

[0032] The heating-side heat exchanger 32 is a heat exchanger heated by the exhaust gas generated by the heating burner 33A. 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. The heating-side first heat exchanger 32A has a plurality of fins 32Z. The second combustion system unit 6 is provided with the heating-side first heat exchanger 32A above a 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 a plurality of heating burners 33A. The heating-side first heat exchanger 32A is supplied with the exhaust gas (combustion exhaust gas) generated by burning gas with the heating burner 33A (gas burner), and functions to heat the heat medium passing through the heating-side first heat exchanger 32A by the heat of this combustion exhaust gas. The heating-side first heat exchanger 32A recovers sensible heat from the combustion exhaust gas discharged from the heating-side burner unit 33. The heating-side second heat exchanger 32B is supplied with the gas after the combustion exhaust gas has passed through the heating-side first heat exchanger 32A, and functions to heat the heat medium passing through the heating-side second heat exchanger 32B by this gas. The heating-side second heat exchanger 32B recovers latent heat from the combustion exhaust gas discharged from the heating-side burner unit 33.

[0033] 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 the flow path of the heat medium. The heat medium circulation path 48 includes a common forward flow path 38K as the heating forward pipe, a first internal flow path 38A as the heating high-temperature forward pipe, a second internal flow path 38B as the heating low-temperature forward pipe, and a common return flow path 38C as the heating return pipe.

[0034] When the first heat dissipation terminal 39A as a heating terminal is connected as shown in FIG. 1, the heat medium circulation path 48 is configured such that the heat medium circulates through the common forward flow path 38K, the first internal flow path 38A, the first terminal flow path 38G of the first heat dissipation terminal 39A, and the common return flow path 38C. When the second heat dissipation terminal 39Z as a heating terminal is connected as shown in FIG. 1, the heat medium circulation path 48 is configured such that the heat medium circulates through the common forward flow path 38K, the second internal flow path 38B, the second terminal flow path 38H of the second heat dissipation terminal 39Z, and the common return flow path 38C.

[0035] The first internal flow path 38A is connected to the first heat dissipation terminal 39A as a flow path so as to communicate with the first terminal flow path 38G provided outside the hot water heater 1. The first internal flow path 38A is configured as a flow path branching from the branch portion 38J, and is configured as a flow path for flowing the heat medium from the branch portion 38J to the first heat dissipation terminal 39A. A part of the first internal flow path 38A is provided in the first heat exchanger 32A on the heating side, and the heat medium passing through the first internal flow path 38A is configured to be heated in the first heat exchanger 32A on the heating side.

[0036] The second internal flow path 38B is connected to the second heat dissipation terminal 39Z as a flow path so as to communicate with the second terminal flow path 38H provided outside the hot water heater 1. The second internal flow path 38B is configured as a flow path branching from the branch portion 38J, and is configured as a flow path for flowing the heat medium from the branch portion 38J to the second heat dissipation terminal 39Z.

[0037] 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. The common return flow path 38C is a flow path through which the heat medium flowing into the inflow portion 35A returns to the expansion tank 36. In the example of FIG. 1, the upstream end of the common return flow path 38C is the inflow portion 35A, and the downstream end of the common return flow path 38C is connected to the inlet portion 36C of the expansion tank 36. The common return flow path 38C is configured as a pipe that introduces the heat medium exiting from the first heat dissipation terminal 39A and the heat medium exiting from the second heat dissipation terminal 39Z into the interior through the inflow portion 35A and causes the heat medium to flow through the heating-side heat exchanger 32 (heating-side second heat exchanger 32B). The common return flow path 38C is configured to communicate with the first heat dissipation terminal 39A and the second heat dissipation terminal 39Z and is connected to the first heat dissipation terminal 39A and the second heat dissipation terminal 39Z as a flow path for flowing the heat medium.

[0038] An intermediate pipe 38D and an intermediate pipe 38E are provided between the outlet of the heating-side second heat exchanger 32B and the inlet of the heating-side first heat exchanger 32A. In the paths of the intermediate pipes 38D and 38E, the expansion tank 36 and the heating circulation pump 37 are provided, and the heat medium can flow from the heating-side second heat exchanger 32B to the heating-side first heat exchanger 32A through the intermediate pipe 38D, the expansion tank 36, and the intermediate pipe 38E. The intermediate pipe 38D is a part of the common return flow path 38C and is a flow path between the outlet of the heating-side second heat exchanger 32B and the inlet portion 36C of the expansion tank 36. The intermediate pipe 38E is a pipe constituted by a part of the common forward flow path 38K and the first internal flow path 38A and is provided between the outlet portion 36B of the expansion tank 36 and the inlet of the heating-side first heat exchanger 32A.

[0039] The common forward flow path 38K is configured as a flow path that introduces the heat medium flowing out from the outlet portion 36B and flows the heat medium flowing out from the expansion tank 36. A heating circulation pump 37 is provided in the middle of the common forward flow path 38K. The heating circulation pump 37 causes the heat medium in the common forward flow path 38K to flow from the expansion tank 36 side to the branch portion 38J side.

[0040] The second internal flow path 38B is provided with a configuration in which a plurality of internal branch paths 38F branch off. A switching 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 second heat radiation terminal 39Z and is connected to the second heat radiation terminal 39Z outside the appliance. The downstream sides of the first heat radiation terminal 39A and the second heat radiation terminal 39Z communicate with a common return flow path 38C. The first heat radiation 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 second heat radiation terminal 39Z is, for example, a low-temperature heating terminal such as floor heating in a dressing room.

[0041] The heating high-temperature thermistor 40 is provided in the first internal flow path 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 heating high-temperature thermistor 40 corresponds to the temperature of the heat medium flowing into the first heat radiation terminal 39A during the circulation of the heat medium passing through the first heat radiation terminal 39A. The heating low-temperature thermistor 41 is provided in the expansion tank 36. The temperature detected by the heating low-temperature thermistor 41 corresponds to the temperature of the heat medium flowing into the second heat radiation terminal 39Z during the circulation of the heat medium passing through the second heat radiation terminal 39Z.

[0042] 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 with 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 (cut-off state). The supply and cut-off of the fuel gas to each of the burner blocks 34A and 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 stage number. Note that the heating circuit 3 is also provided with an ignition electrode, a heating frame rod, and the like.

[0043] In the heating circuit 3, due to the operation of the heating circulation pump 37, the hot water heated by the heating-side heat exchanger 32 circulates through the heat medium circulation path 48. Specifically, in the heating circuit 3, when the heating circulation pump 37 operates, the hot water flowing through the heat medium circulation path 48 is heated by the combustion exhaust gas discharged from the heating-side burner unit 33 in the heating-side heat exchanger 32, and circulates through the common return flow path 38C, the first internal flow path 38A, and the first heat dissipation terminal 39A, and at the same time, circulates through the common return flow path 38C, the second internal flow path 38B, and the second heat dissipation terminal 39Z. In the example of FIG. 1, hot water is supplied to the first heat dissipation terminal 39A according to the operation of the high-temperature switching valve 39H, which is a built-in thermostatic valve. The second heat dissipation terminal 39Z is configured as a low-temperature heating terminal, and hot water is supplied to the second heat dissipation terminal 39Z according to the operation of the switching valve 39G, which is a thermostatic valve inside the appliance.

[0044] As shown in FIG. 1, the bath heating pipe 51 is provided in a configuration branched from the first internal flow path 38A. The bath heating pipe 51 branches from a position on the downstream side of the heating-side heat exchanger 32 in the heat medium circulation path 48 (specifically, on the downstream side 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 first internal flow path 38A and the common return flow path 38C so as to communicate with each other.

[0045] The control valve 58 is a valve provided on the upstream side of the bath heat exchanger 50 in the bath heating pipe 51. The control valve 58 is configured to open and close the bath heating pipe 51, and is configured to switch between a closed state that blocks the water flow passing through itself in the bath heating pipe 51 and an open state that allows the water flow passing through itself in the bath heating pipe 51. The control valve 58 has a switch. This switch is configured as a limit switch, and when the control valve 58 is in the fully open state where it is most open, it enters a first state that outputs a predetermined first signal (for example, an on signal), and when the control valve 58 is in the fully closed state where it is blocked, it enters a second state that outputs a second signal (for example, an off signal) different from the first signal.

[0046] The hot water supply and heating machine 1 further includes a control device 70, a hot water supply remote controller 71, a bath remote controller 72, a heating remote controller 73, 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 above memory. The control device 70 is configured to be able to acquire signals from various sensors and switches (thermistors, water volume sensors, switches, etc.), and controls a hot water supply circuit 2, a heating circuit 3, a bath circuit 4, etc. The above room temperature thermistor is provided as a temperature detection means for detecting the temperature in the dressing room, for example, in the dressing room. Note that the control device 70 may be constituted by a single device (for example, a controller configured as a single unit), or may be constituted by a plurality of devices.

[0047] 2. Basic operation of the hot water supply and heating machine 1 (Normal hot water supply operation) When a hot water supply faucet provided outside the device to communicate with the hot water outlet pipe 10 is opened and water flows into the appliance, and the water volume sensor 14 outputs a signal indicating the flow of water, the control device 70 rotates the fan 20 for a predetermined time to discharge the combustion exhaust gas stored in the hot water supply combustion chamber 5A (purging). Thereafter, the control device 70 opens the original gas solenoid valve 17 of the gas pipe 16 and each solenoid valve 19, and opens the gas proportional valve 18 at a predetermined opening degree, and controls to supply gas to each hot water supply burner 8A, and operates the igniter to ignite the hot water supply burner 8A. When gas is burned by the hot water supply burner 8A by such control, the water passing through the hot water supply side heat exchanger 7 is heated by the combustion exhaust gas generated by the combustion and the hot water discharge operation is performed so as to flow to the hot water outlet pipe 10, and the heated hot water is discharged from the above hot water supply faucet.

[0048] 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 discharge pipe 10, and controls the opening and closing of the solenoid valve 19 and adjusts the opening degree of the gas proportional valve 18 so that the hot water temperature becomes the set temperature indicated by the hot water supply remote controller 71 or the bath remote controller 72. At the same time, the air volume is continuously changed by controlling the rotational speed of the fan 20. When the hot water supply faucet is closed during the above-mentioned hot water discharging operation and the signal output by the water volume sensor 14 indicates a water flow stop state, the control device 70 closes the original gas solenoid valve 17 and the solenoid valve 19 to extinguish the hot water supply burner 8A, and rotates the fan 20 for a predetermined time to perform post-purge.

[0049] (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 controller 71 or the bath remote controller 72 is pressed, the control device 70 sets the hot water temperature to the hot water filling temperature set by the hot water supply remote controller 71 or the bath remote controller 72 as the target temperature (for example, 40 ° C) and starts hot water filling. Specifically, the control device 70 opens the hot water supply solenoid valve 60 in the dropping 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 discharge pipe 10. The hot water flowing through the hot water discharge pipe 10 in this way is supplied to the bathtub 52 through the dropping pipe 59 and the bath return pipe 54.

[0050] 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 dropping water volume sensor 61 provided in the dropping pipe 59 (the 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 set water volume, the control device 70 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 bath circulation pump 55 to circulate the hot water in the bathtub 52 in the bath circuit 4. When the control device 70 finishes the hot water filling, it notifies the hot water supply remote controller 71 or the bath remote controller 72 of the end of the hot water filling.

[0051] (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, opens the control valve 58, 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, and when it is confirmed that the temperature has reached, the control device 70 extinguishes the heating burner 33A, stops the bath circulation pump 55, and ends the reheat. When the control device 70 ends the reheat, it notifies the hot water supply remote control 71 or the bath remote control 72 of the end of the reheat.

[0052] 3. Configuration for supplying the heat medium to the first heat radiation terminal 39A (high-temperature heating terminal) and the second heat radiation terminal 39Z (low-temperature heating terminal) The hot water supply and heating unit 1 constitutes a hot water supply system while being connected to the first heat radiation terminal 39A and the second heat radiation terminal 39Z, and supplies the heat medium branched by the internal branched flow path to the external first heat radiation terminal 39A and the second heat radiation terminal 39Z.

[0053] As shown in FIG. 1, the downstream end of the common flow path 38K in the heat medium circulation path 48 is a branch portion 38J. The branch portion 38J is a portion that branches the flow of the heat medium flowing through the common flow path 38K. The upstream side of the branch portion 38J is the common flow path 38K, and the downstream side of the branch portion 38J branches into a first internal flow path 38A and a second internal flow path 38B. The first internal flow path 38A has a reheat branch portion 56 that branches into the bath circuit 4, and on the bath circuit 4 side branched by the reheat branch portion 56, the bath heating pipe 51 passes through the bath heat exchanger 50 and is connected to the common return flow path 38C. The lower side (downstream side) of the reheat branch portion 56 has a connection portion 46B that branches into the bypass flow path 46.

[0054] The bypass flow path 46 is provided between the common return flow path 38C and the first internal flow path 38A. The bypass flow path 46 is a path through which the heat medium can flow so as to bypass between the common return flow path 38C and the first internal flow path 38A.

[0055] The downstream end of the first internal flow path 38A is configured to be connectable to the outside and is a first outflow portion 35B through which the heat medium flows out. The first outflow portion 35B is provided at the downstream end of the first internal flow path 38A and is configured as an outlet for flowing out the heat medium from the first internal flow path 38A toward the first terminal flow path 38G. The downstream end of the second internal flow path 38B is configured to be connectable to the outside and is a second outflow portion 35C through which the heat medium flows out. The second outflow portion 35C is provided at the downstream end of the second internal flow path 38B and is configured as an outlet for flowing out the heat medium from the second internal flow path 38B toward the second terminal flow path 38H. The upstream end of the common return flow path 38C is configured to be connectable to the outside and is an inflow portion 35A through which the heat medium flows in. The inflow portion 35A is provided on the downstream side of the first terminal flow path 38G and on the downstream side of the second terminal flow path 38H, and is an inlet through which the heat medium flowing through the first terminal flow path 38G flows in, and is also an inlet through which the heat medium flowing through the second terminal flow path 38H flows in.

[0056] Outside the water heater 1, a first heat dissipation terminal 39A and a second heat dissipation terminal 39Z are provided, to which the heat medium is supplied from the water heater 1 and which communicate with the heat medium circulation path 48. The first heat dissipation terminal 39A has a first terminal flow path 38G through which the heat medium flows, and dissipates the heat of the heat medium flowing through the first terminal flow path 38G. In the space near the first heat dissipation terminal 39A, the air is heated by the heat of the heat medium flowing through the first terminal flow path 38G being dissipated. The first heat dissipation terminal 39A is configured as a high-temperature heating terminal. The second heat dissipation terminal 39Z has a second terminal flow path 38H through which the heat medium flows, and dissipates the heat of the heat medium flowing through the second terminal flow path 38H. In the space near the second heat dissipation terminal 39Z, the air is heated by the heat of the heat medium flowing through the second terminal flow path 38H being dissipated. The downstream end of the first terminal flow path 38G and the downstream end of the second terminal flow path 38H are configured to be connectable so as to communicate with the inflow portion 35A of the water heater 1.

[0057] The supply of the heat medium to the first terminal flow path 38G is switched between a state where the supply of the heat medium is blocked (second state) and a state where it is permitted (first state) by opening and closing the high-temperature switching valve 39H. In the state where the high-temperature switching valve 39H is open (first state), it is allowed for the heat medium to pass through the high-temperature switching valve 39H, and it is allowed for the heat medium to flow from the inside of the first internal flow path 38A, through the first terminal flow path 38G, and to the downstream side (inflow part 35A side) of the high-temperature switching valve 39H. In the state where the high-temperature switching valve 39H is closed (second state), it is blocked for the heat medium to pass through the high-temperature switching valve 39H, and the heat medium does not flow from the inside of the first internal flow path 38A to the downstream side of the high-temperature switching valve 39H. The supply of the heat medium to the second terminal flow path 38H is switched between a state where the supply of the heat medium is blocked (second state) and a state where it is permitted (first state) by opening and closing the switching valve 39G. In the state where the switching valve 39G is open (first state), it is allowed for the heat medium to pass through the switching valve 39G, and it is allowed for the heat medium to flow from the inside of the second internal flow path 38B, through the second terminal flow path 38H, and to the downstream side (inflow part 35A side) of the switching valve 39G. In the state where the switching valve 39G is closed (second state), it is blocked for the heat medium to pass through the switching valve 39G, and the heat medium does not flow from the inside of the second internal flow path 38B to the downstream side of the switching valve 39G. Both the high-temperature switching valve 39H and the switching valve 39G are thermostatic valves. The thermostatic valve, for example, expands the expansion body with the heat of a heating element (Positive Temperature Coefficient) when the power is on, pushes the piston to open the valve so that hot and cold water can flow, and when the power is off, the heating element radiates heat naturally to contract the expansion body and close the valve.

[0058] The heat medium that has flowed into the inflow part 35A circulates through the heat medium circulation path 48 in the water heater 1. Specifically, the heat medium flows downstream from the inflow part 35A through the common return flow path 38C, is heated by the heating-side second heat exchanger 32B, then passes through the expansion tank 36, and is further moved downstream by the power of the heating circulation pump 37. Then, the heat medium that has flowed toward the branch part 38J is divided at the branch part 38J into the heat medium going toward the first internal flow path 38A and the heat medium going toward the second internal flow path 38B. The heat medium flowing through the first internal flow path 38A is heated by the heating-side first heat exchanger 32A on the way.

[0059] The heat medium flowing through the first internal flow path 38A flows out toward the first terminal flow path 38G with the first outflow part 35B as the outlet. The heat medium flowing through the second internal flow path 38B flows out as the heat medium toward the second terminal flow path 38H with the second outflow part 35C as the outlet.

[0060] The high-temperature switching valve 39H that opens and closes the first terminal flow path 38G, the switching valve 39G that opens and closes the second internal flow path 38B, and the heating circulation pump 37 are controlled by the control device 70. The control device 70 is electrically connected to each of the high-temperature switching valve 39H, the switching valve 39G, and the heating circulation pump 37, and performs opening and closing control of the high-temperature switching valve 39H and the switching valve 39G and drive control of the heating circulation pump 37.

[0061] 4. Configuration for detecting a short circuit in the path between wirings connected to adjacent terminals (pin terminals) The control device 70 is configured to include a microcomputer 70A (microcomputer) corresponding to an example of a control unit. The microcomputer 70A has an information processing function and is configured as a microcomputer that performs various operations and various controls. As shown in FIG. 2, a plurality (a large number) of pin terminals P1 to P6 are provided side by side on the outer peripheral edge side of the microcomputer main body. Each of the pin terminals P1 to P6 corresponds to an example of a terminal. A large number of pin terminals are formed in a large number over the entire circumference of the microcomputer 70A. However, in FIG. 2, for simplicity, six pin terminals P1 to P6 (pin terminals connected to one or a plurality of six switching valves for operating one or a plurality of six second heat radiation terminals 39Z) are shown in the drawing, and other large numbers of pin terminals are omitted.

[0062] Each of the pin terminals P1 to P6 is connected to the corresponding switching valves V1 to V6 (six switching valves 39G) by wiring such as a communication cable. Specifically, the pin terminal P1 is connected to the switching valve V1 via the wiring L1, the pin terminal P2 is connected to the switching valve V2 via the wiring L2, the pin terminal P3 is connected to the switching valve V3 via the wiring L3, the pin terminal P4 is connected to the switching valve V4 via the wiring L4, the pin terminal P5 is connected to the switching valve V5 via the wiring L5, and the pin terminal P6 is connected to the switching valve V6 via the wiring L6.

[0063] Figure 3 is a diagram showing the inside of the microcomputer 70A corresponding to each of the pin terminals P1 to P6. As shown in Figure 3, the microcomputer 70A includes an input unit 78 to which an input signal is input from the outside via the pin terminals P1 to P6, and an output unit 77 that outputs an output signal to the outside via the pin terminals P1 to P6. The input unit 78, the output unit 77, and the pin terminals P1 to P6 are connected via internal signal lines. The output unit 77 is capable of outputting a high-level voltage signal (hereinafter also referred to as a Hi signal. For example, 5 [V]) and a low-level voltage signal (hereinafter also referred to as a Lo signal. For example, 0 [V]) via the pin terminals P1 to P6. The input unit 78 receives an input signal via the pin terminals P1 to P6, and the microcomputer 70A detects a short circuit depending on whether the input signal to the input unit 78 is a high-level voltage signal (Hi signal) or a low-level voltage signal (Lo signal). Although details will be described later, when a high-level voltage signal is input when the switching valves V1 to V6 should be in the closed state and a low-level voltage signal should be input, it is highly likely that the voltage of another path has flowed in due to a short circuit, so a short circuit is detected.

[0064] When a Hi signal is output from the microcomputer 70A to the corresponding switching valves V1 to V6 via the pin terminals P1 to P6 according to the operation of the heating remote control 73 or the like, the corresponding switching valves V1 to V6 open, and the heat medium is supplied to the second heat dissipation terminal 39Z (low-temperature heating terminal) communicating with the switching valves V1 to V6, and heating of the corresponding second heat dissipation terminal 39Z starts. On the other hand, when a Lo signal (or no voltage signal) is output from the microcomputer 70A to the corresponding switching valves V1 to V6 via the pin terminals P1 to P6, the corresponding switching valves V1 to V6 close, the heat medium is not supplied to the second heat dissipation terminal 39Z, and heating is not performed.

[0065] 5. Control for Detecting a Short Circuit in the Path between Wires Connected to Adjacent Pin Terminals Hereinafter, the control when opening the switching valve V1 will be described. Figure 4 shows the input and output signals of the microcomputer 70A at each stage of (1) before the on operation of the second heat dissipation terminal (heating terminal), (2) after the on operation of the second heat dissipation terminal (heating terminal), and (3) the detection operation.

[0066] (1) Before the power supply of the second heat dissipation terminal 39Z (heating terminal) is turned on, the microcomputer 70A outputs Lo signals to all the switching valves V1 to V6. Here, when an operation to start heating is performed from a heating remote controller 73 or the like corresponding to the switching valve V1, (2) the microcomputer 70A outputs a Hi signal to the switching valve V1 via the pin terminal P1 from the output unit 77 thereof. For the other switching valves V2 to V6, the microcomputer 70A outputs Lo signals to the corresponding switching valves V2 to V6 via the pin terminals P2 to P6 from the output unit 77 thereof. The Hi signal output from the microcomputer 70A via the pin terminal P1 is input to the switching valve V1 via the wiring L1, and opens the switching valve V1 (thermostatic valve). The Lo signals output from the microcomputer 70A via the pin terminals P2 to P6 are input to the switching valves V2 to V6 via the wirings L2 to L6, and maintain the closed states of the switching valves V2 to V6 (thermostatic valves). Here, when a short circuit S1 (see FIG. 2) occurs between the wirings L1 and L2 due to some factor, not only the switching valve V1 but also a Hi signal is input to the switching valve V2, and the switching valve V2 is opened. In this case, there is a problem that the heat medium is supplied to the second heat dissipation terminal 39Z connected to the switching valve V2, and heat dissipation of the second heat dissipation terminal 39Z not intended by the user occurs.

[0067] Therefore, in the present embodiment, after the microcomputer 70A outputs a Hi signal from the output unit 77 via the pin terminal P1, the following short circuit detection operation is performed. (3) An input signal is made inputtable to the input unit 78 connected to the pin terminal P2 (adjacent to the pin terminal P1) of the microcomputer 70A for a predetermined time (for example, several milliseconds, several tens of milliseconds, several seconds, etc.). Specifically, for the microcomputer 70A, the output of the Lo signal via the pin terminal P2 is stopped, the setting of the microcomputer 70A is changed, and the input of an input signal from the outside to the input unit 78 via the pin terminal P2 is made possible. After the elapse of the predetermined time, the setting of the microcomputer 70A is restored, and the output of the Lo signal from the output unit 77 via the pin terminal P2 to the switching valve V2 is performed as usual.

[0068] If there is no short circuit S1 between the wirings L1 and L2, a Lo signal (instead of a Hi signal) is input to the input section 78 of the microcomputer 70A connected to the pin terminal P2. Therefore, when the microcomputer 70A detects the input of the Lo signal, it determines that there is no abnormality such as a short circuit S1 between the wirings L1 and L2. On the other hand, when the microcomputer 70A detects that a signal with a voltage higher than the Lo signal is input to the microcomputer 70A via the pin terminal P2, since there is a high possibility that a high voltage is flowing in from a path other than the wiring L2, the microcomputer 70A determines that an abnormality such as a short circuit S1 has occurred between the wirings L1 and L2. When the microcomputer 70A determines that an abnormality has occurred, it displays an error and the type of the error (a number indicating a short circuit abnormality, etc.) on a display means such as the heating remote controller 73, and closes the switching valve V2 (by manual setting or the like) to stop the supply of the heat medium (hot water) to the second heat dissipation terminal 39Z communicating with the switching valve V2. In the present embodiment, the microcomputer 70A and the heating remote controller 73 correspond to an example of the notification section.

[0069] In the above, the switching valve V1 is an example of the first switching valve, the switching valve V2 is an example of the second switching valve, the pin terminal P1 is an example of the first terminal, the pin terminal P2 is an example of the second pin terminal, the wiring L1 is an example of the first path, and the wiring L2 is an example of the second path.

[0070] Next, the control when the switching valve V2 is opened will be described. FIG. 5 shows the input / output signals of the microcomputer 70A at each stage of (1) before the ON operation of the second heat dissipation terminal (heating terminal), (2) after the ON operation of the second heat dissipation terminal (heating terminal), and (3) the detection operation.

[0071] (1)Before the power of the second heat dissipation terminal 39Z (heating terminal) is turned on, the microcomputer 70A outputs Lo signals to all the switching valves V1 to V6. Here, when an operation to start heating is performed from a heating remote controller 73 or the like corresponding to the switching valve V2, (2) the microcomputer 70A outputs a Hi signal to the switching valve V2 via the pin terminal P2 from the output unit 77 thereof. For the other switching valves V1, V3 to V6, the microcomputer 70A outputs Lo signals to the corresponding switching valves V1, V3 to V6 via the pin terminals P1, P3 to P6 from the output unit 77 thereof. The Hi signal output from the microcomputer 70A via the pin terminal P2 is input to the switching valve V2 via the wiring L2, and opens the switching valve V2 (thermal valve). The Lo signals output from the microcomputer 70A via the pin terminals P1, P3 to P6 are input to the switching valves V1, V3 to V6 via the wirings L1, L3 to L6, and maintain the closed states of the switching valves V1, V3 to V6 (thermal valves). After the microcomputer 70A outputs a Hi signal via the pin terminal P2 from the output unit 77, the following short - circuit detection operation is performed. (3) An input signal is made input - able to the input unit 78 connected to the pin terminals P1, P3 of the microcomputer 70A for a predetermined time (for example, several milliseconds, several tens of milliseconds, several seconds, etc.). Specifically, for the microcomputer 70A, the output of the Lo signal via the pin terminals P1, P3 is stopped, and the setting of the microcomputer 70A is changed so that an input signal can be input to the input unit 78 from the outside via the pin terminals P1, P3. After making the input signal input - able to the input unit 78, after a predetermined time has elapsed, the setting of the microcomputer 70A is restored, and normally, the Lo signal is output from the output unit 77 to the switching valves V1, V3 via the pin terminals P1, P3. In the above, the switching valve V2 is taken as an example of the first switching valve, the switching valves V1, V3 are taken as examples of the second switching valves, the pin terminal P2 is taken as an example of the second pin terminal, the pin terminals P1, P3 are taken as examples of the second pin terminals, the wiring L2 is taken as an example of the first path, and the wirings L1, L3 are taken as examples of the second paths.

[0072] Note that when outputting a Hi signal from other pin terminals P3 to P6 as well, after outputting the Hi signal, since the input via the pin terminal adjacent to the pin terminal that has output the Hi signal is made possible, the description is omitted.

[0073] 6. Examples of Effects The microcomputer 70A of the water heater 1 includes a first terminal connected to the first switching valve via a first path among a plurality of switching valves 39G, and a second pin terminal that is disposed adjacent to the first terminal and is connected to the second switching valve among the plurality of switching valves 39G via a second path. When the microcomputer 70A outputs a high-level output signal via the first terminal, the microcomputer 70A enables the input of an input signal via the second pin terminal, and based on the input signal, detects the presence or absence of a short circuit between the first path and the second path. According to the above configuration, when a high-level output signal is output from the microcomputer 70A via the first terminals P1 to P6, an input signal is input via the adjacent second pin terminals P1 to P6. If a low-level input signal is input to the microcomputer 70A via the second pin terminals P1 to P6, it is detected that no short circuit has occurred (because no high-level voltage signal has flowed in due to the short circuit). On the other hand, if a low-level input signal is not input via the second pin terminals P1 to P6 (if a high-level or at least a voltage higher than the low level is input due to the inflow of the voltage signal), the microcomputer 70A detects that a short circuit has occurred. As a result, when a short circuit is detected, it becomes possible to display the type of error or stop the heating operation. Therefore, it is possible to suppress the malfunction due to the short circuit of the paths connected to the plurality of adjacent pin terminals P1 to P6 in the microcomputer 70A.

[0074] After the microcomputer 70A performs the input of the input signal via the second pin terminals P1 to P6 for a predetermined time during which short circuit detection is possible, the microcomputer 70A switches to a state in which it outputs an output signal via the second pin terminals P1 to P6. If the microcomputer 70A, which is originally set for output, is set to detect an input signal, the load on the microcomputer 70A may become excessive. According to the above configuration, since the input detection time can be suppressed to a predetermined time, the load on the microcomputer 70A can be suppressed.

[0075] <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.

[0076] In the above embodiment, a configuration is provided for detecting a short circuit in the path to a plurality of second heat dissipation terminals 39Z (low-temperature heating terminals), but it is not limited thereto. For example, a configuration for detecting a short circuit in the path to the first heat dissipation terminal 39A (high-temperature heating terminal) may also be used.

[0077] It should be considered that all aspects of the embodiments disclosed this time are illustrative and not restrictive. The scope of the present invention is not limited to the embodiments disclosed this time, and it is intended to include all modifications within the scope indicated by the claims or within the scope equivalent to the claims.

Explanation of Reference Numerals

[0078] 1: Hot water heater 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 7Z: Fin 8: Hot water supply side burner unit 8A: Hot water supply burner 9A: Burner block 9B: Burner block 9C: Burner block 10: Hot water outlet pipe 11: Water supply pipe 20: Fan 20A: Drive source 20B: Rotating body 32: Heating side heat exchanger (heat exchanger) 32A: First heating side heat exchanger 32B: Second heat exchanger on the heating side 33: Heating side burner unit 33A: Heating burner (gas burner) 34A: Burner block 34B: Burner block 35A: Inlet section 35B: First outlet section 35C: Second outlet section 36: Expansion tank 36C: Inlet part 36B: Outlet part 37: Heating circulation pump 38A: First internal flow path 38B: Second internal flow path 38C: Common return flow path 38K: Common forward flow path 38J: Branch section 39A: First heat dissipation terminal 39Z: Second heat dissipation terminal 38G: First terminal flow path 38H: Second terminal flow path 39H: High temperature switching valve 46: Bypass flow path 48: Heat medium circulation path 50: Bathtub heat exchanger 56: Supplementary heating branch section 70: Control device 70A: Microcomputer (control section, notification section) 77: Output section 78: Input section P1~P6: Pin terminals V1~V6, 39G: Switching valves L1~L6: Wires

Claims

1. A hot water and heating machine configured to supply a heat medium to a plurality of heat dissipation terminals and to control respective switching valves provided corresponding to the terminal flow paths of the respective heat dissipation terminals, the hot water and heating machine switching the state of the switching valve between a first state that permits supply of the heat medium to the terminal flow path corresponding to the switching valve and a second state that shuts off the supply, comprising: A hot water supply circuit that heats water supplied from the outside to supply hot water; A heat medium circulation path that forms a path for circulating the heat medium together with the terminal flow path, a gas burner that burns gas, and a heat exchanger that heats the heat medium flowing through the heat medium circulation path with combustion exhaust generated by combustion in the gas burner, and a heating circuit that supplies the heat medium heated by the heat exchanger to the terminal flow path via the heat medium circulation path; A control unit that controls the opening and closing operations of the plurality of switching valves by outputting high-level and low-level signals to each of the plurality of terminals; Comprising; A first terminal among the plurality of terminals is a terminal that outputs a signal instructing an opening operation and a signal instructing a closing operation to a first switching valve among the plurality of switching valves via a first path; A second terminal among the plurality of terminals is a terminal adjacent to the first terminal and outputs a signal instructing an opening operation and a signal instructing a closing operation to a second switching valve among the plurality of switching valves via a second path; The control unit monitors an input signal input to the second terminal in an output state in which a high-level signal is output to the first terminal, and detects a short circuit between the first path and the second path based on the input signal in the output state Hot water and heating machine.

2. After monitoring the input signal in the output state for a predetermined time, the control unit switches to a state of outputting a signal instructing an opening operation or a signal instructing a closing operation to the second terminal The hot water and heating machine according to Claim 1.

3. The control unit detects the short circuit when changing the opening and closing state of the first switching valve The hot water and heating machine according to Claim 1 or Claim 2.

4. Having a notification unit that notifies error information indicating the short circuit when the short circuit is detected The hot water and heating machine according to Claim 1 or Claim 2.

Images