JP2017096508A - Thermal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique capable of preventing a heat medium from freezing even when a thermal device mounted with a heat pump heat source is in power restriction operation.SOLUTION: A thermal device comprises: a heat pump unit mounted with a heat pump heat source; and a tank unit mounted with a tank. The thermal device can perform normal operation and power restriction operation with a restricted power supply lower than a maximum power supply available during normal operation. The thermal device also has a first heater which is installed in the tank unit and heats the heat medium therein by consuming power. A control unit is configured to be able to perform freezing prevention action which drives the first heater and heating action which drives the heat pump heat source and stores the heat medium heated by the same. The heating action is performed when the freezing prevention action is not performed during the power restriction operation.SELECTED DRAWING: Figure 5

Description

  The technology disclosed in this specification relates to a thermal apparatus.

  Patent Document 1 discloses a burner for heating a heat medium, a hot water supply passage through which the heat medium heated by the burner flows, a heater for preventing freezing of the heat medium in the hot water supply passage, and a liquid fuel supplied to the burner. And a control device that adjusts the supply amount of heat. The control device is configured to be capable of antifreezing operation in which the heater is heated to heat the heat medium in the hot water supply passage. The thermal device of Patent Document 1 has a normal operation in which the power supply source is a commercial power supply and a power suppression operation in which the power supply source is a secondary battery. During the power suppression operation, it is necessary to operate the thermal device at a suppression power lower than the maximum power that can be used during normal operation. The thermal device of Patent Literature 1 suppresses the power consumption of the thermal device during the power suppression operation by prohibiting the freeze prevention operation during the power suppression operation.

JP2013-88060A

  As a means for heating the heat medium, there is a thermal apparatus including a heat pump heat source that consumes electric power and heats the heat medium. In such a thermal device, as compared with a thermal device that heats the heat medium with a burner as in Patent Document 1, the electric power required to heat the heat medium becomes larger. It is preferable that such a thermal device also includes a power suppression operation that consumes less power than the normal operation, and can operate in the power suppression operation as necessary, as in the thermal device of Patent Document 1.

  In the power suppression operation of Patent Document 1, the power consumption of the thermal device during the power suppression operation is suppressed by prohibiting the freeze prevention operation. However, if the freeze prevention operation is completely prohibited, the heat medium in the hot water supply channel may freeze during the power suppression operation. When the heating medium in the hot water supply channel freezes, the heating medium cannot flow in the hot water supply channel until the frozen heating medium melts. In a thermal device including a heat pump heat source and a tank for storing a heat medium, a technology that can achieve both storage of heat in the tank and prevention of freezing of the heat medium while operating in a power suppression operation is expected.

  The present specification proposes a technique capable of preventing the heat medium from freezing even in a thermal apparatus equipped with a heat pump heat source while operating in a power suppression operation.

  The thermal device disclosed in this specification includes a heat pump unit including a heat pump heat source that consumes electric power to heat the heat medium, and a tank unit including a tank that stores the heat medium heated by the heat pump heat source. In addition, it has a normal operation and a power suppression operation that operates at a suppression power lower than the maximum power consumption during the normal operation. The thermal device is provided in the tank unit and has a first heater that consumes electric power and heats the heat medium in the tank unit. The control device is configured to be capable of performing a freeze prevention operation for driving the first heater and a heating operation for driving the heat pump heat source and storing the heat medium heated by the heat pump heat source in the tank. The control device is configured to perform the heating operation when the freeze prevention operation is not performed during the power suppression operation.

  During the power suppression operation, the power consumption of the thermal equipment must be kept below the suppression power. However, if the heating operation and the freeze prevention operation are executed at the same time, the power consumption of the thermal device may be larger than the suppression power. According to the above configuration, during the power suppression operation, the control device performs the heating operation when the freeze prevention operation is not performed. That is, during the power suppression operation, the freeze prevention operation and the heating operation are not performed simultaneously. For this reason, it is possible to prevent the power consumption of the thermal device during the power suppression operation from becoming larger than the suppression power. Further, the freeze prevention operation can be executed during the power suppression operation. For this reason, during power suppression operation, it is possible to achieve both heat storage in the tank and prevention of freezing of the heat medium in the first flow path.

The figure which shows typically the structure of the hot water supply system 2 which concerns on an Example. The figure which shows typically freezing prevention driving | operation during normal driving | operation (A) and electric power suppression driving | operation (B). The figure which shows typically the time zone when hot water supply is performed in a specific household. The figure which represents typically calculation of the scheduled start time of the heat processing during electric power suppression driving | operation. The flowchart which shows a heat processing. The figure which shows typically operation | movement of the heating operation and freezing prevention operation in the case of performing freezing prevention operation during execution of the heating operation in electric power suppression operation.

  The main features of the embodiments described below are listed. The technical elements described below are independent technical elements and exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Absent.

(Feature 1) The heat equipment is provided in the auxiliary heat source unit including an auxiliary heat source that heats the heat medium by combustion of fuel, and the auxiliary heat source unit, and consumes electric power to heat the heat medium in the auxiliary heat source unit. And a second heater. The control device may be configured to drive at least one of the first heater and the second heater in the freeze prevention operation. In this case, the controller, when driving both the first heater and the second heater in the freeze prevention operation during the power suppression operation, at least one of the time for driving the first heater and the time for driving the second heater. The freeze prevention operation may be executed so that the parts overlap each other.

  According to the above configuration, during the power suppression operation, the time during which the first heater is driven and the time during which the second heater is driven are adjusted to overlap. In this case, the time during which the heating operation is performed can be secured by lengthening the time during which the driving is not performed.

(Feature 2) The control device stops the heating operation and executes the anti-freezing operation when the anti-freezing operation is to be executed during the heating operation during the power suppression operation. The heating operation may be resumed.

  According to the above configuration, in the power suppression operation, the freeze prevention operation is executed with priority over the heating operation. Thereby, freezing of the heat medium in the tank unit can be reliably prevented. Further, since the heating operation is resumed after the freeze prevention operation is completed, the heating operation can be reliably terminated.

(Characteristic 3) The control device may be configured to set the scheduled start time of the heating operation according to the past use record of the heat medium, and execute the heating operation when the set scheduled start time is reached. In this case, if the control device performs the heating operation at the set scheduled start time during the power suppression operation, the anti-freezing operation is to be performed by the end of the heating operation. It is good to advance the time.

  In the power suppression operation, when the freeze prevention operation is performed during the heating operation, the power consumption of the thermal device may exceed the suppression power, so the heating operation must be interrupted. According to said structure, heating operation can be complete | finished before freezing prevention operation is performed. Thereby, heating operation can be completed by the completion scheduled time which was initially planned, without interrupting heating operation.

(Example)
As shown in FIG. 1, the hot water supply system 2 according to this embodiment includes an HP (heat pump) unit 4, a tank unit 6, and a burner unit 8.

  The HP unit 4 is a heat source that absorbs heat from outside air and heats water. The HP unit 4 includes a compressor 10, a condenser 12, an expansion valve 14, and an evaporator 16. The HP unit 4 circulates a refrigerant (for example, a fluorocarbon refrigerant) in the order of the compressor 10, the condenser 12, the expansion valve 14, and the evaporator 16, thereby absorbing heat from outside air and heating water. The compressor 10 pressurizes the refrigerant to a high temperature and a high pressure. The condenser 12 cools the refrigerant by exchanging heat with water. An HP forward path 19 and an HP return path 21 are connected to both ends of the water flow path of the condenser 12, respectively. The expansion valve 14 depressurizes the refrigerant to low temperature and low pressure. The evaporator 16 heats the refrigerant by exchanging heat with the outside air. The HP unit 4 further includes a circulation pump 18 that circulates water through the condenser 12, a return thermistor 20 that detects the temperature of water flowing into the condenser 12, and a forward thermistor 22 that detects the temperature of water flowing out of the condenser 12. An HP outside air temperature thermistor 23 that detects the outside air temperature and an HP controller 24 that controls the operation of each component of the HP unit 4 are provided.

  The tank unit 6 includes a tank 30, a mixing valve 32, a bypass control valve 34, and a tank outside air temperature thermistor 39 that detects the outside air temperature. The tank 30 is a sealed container that is covered with a heat insulating material and stores water therein. The capacity of the tank 30 of this embodiment is, for example, 100 liters. When the circulation pump 18 of the HP unit 4 is driven, the water at the bottom of the tank 30 is sent to the condenser 12 via the tank going path 31 and the HP going path 19. The water heated by the condenser 12 and heated to a high temperature is returned from the top of the tank 30 into the tank 30 via the HP return path 21 and the tank return path 33. A first heater 35 that consumes electric power and heats the water in the tank going-out path 31 and the tank returning path 33 is attached to the tank going-out path 31 and the tank returning path 33. When the water heated by the HP unit 4 flows into the tank 30, a temperature stratification is formed in the tank 30 in which a high-temperature water layer is stacked on a low-temperature water layer. An upper thermistor 36 that detects the temperature of the upper water, an intermediate thermistor 37 that detects the temperature of the intermediate water, and a lower thermistor 38 that detects the temperature of the lower water are attached to the tank 30. In this embodiment, the upper thermistor 36 is disposed at a position 6 liters from the top of the tank 30, the intermediate thermistor 37 is disposed at a position 12 liters from the top of the tank 30, and the lower thermistor 38 is disposed at the tank 30. 30 liters from the top of the. The state in which the tank 30 is filled with water heated by the HP unit is referred to as a “full storage state”.

  Tap water is supplied to the tank unit 6 through the water supply path 40. A pressure reducing valve 42 for reducing the water supply pressure, a water inlet thermistor 44 for detecting the water supply temperature TW, and a first heater 35 for consuming electric power and heating the water in the water supply passage 40 are attached to the water supply passage 40. . The water supply path 40 branches into a tank water supply path 46 that communicates with the bottom of the tank 30 and a tank bypass path 48 that communicates with the mixing valve 32. Check valves 50 and 52 are attached to the tank water supply path 46 and the tank bypass path 48, respectively. In addition, a first heater 35 that consumes electric power and heats the water in the tank water supply path 46 is attached to the tank water supply path 46. In addition, a water-side water amount sensor 54 that detects the flow rate of tap water flowing into the mixing valve 32 and a first heater 35 that consumes electric power and heats the water in the tank bypass passage 48 are attached to the tank bypass passage 48. It has been. The top of the tank 30 and the mixing valve 32 communicate with each other via a tank hot water path 56. In the tank hot water path 56, a check valve 58, a first heater 35 that consumes electric power to heat the water in the tank hot water path 56, and a flow rate of water from the tank 30 that flows into the mixing valve 32 are detected. A hot water sensor 60 is attached.

  The mixing valve 32 mixes the tap water flowing from the tank bypass passage 48 and the water from the tank 30 flowing from the tank discharge passage 56 and sends it out to the first hot water supply passage 62. The mixing valve 32 is driven by a stepping motor to adjust the opening degree on the tank bypass path 48 side (opening side on the water side) and the opening degree on the tank discharge path 56 side (opening side on the hot water side). A mixing thermistor 64 that detects the temperature of the water fed from the mixing valve 32 is attached to the first hot water supply path 62. Further, in the first hot water supply path 62, the first hot water supply path 62 and the downstream side of the hot water supply bypass path 72 are connected to the first and second hot water supply paths 62 to consume water and heat the water in the first hot water supply path 62. A heater 35 is attached.

  Hot water is supplied from the tank unit 6 to hot water supply points such as a kitchen, a shower, and a currant through the second hot water supply path 66. A hot water supply outlet thermistor 68 that detects the temperature of water supplied to the hot water supply location and a check valve 70 are attached to the second hot water supply path 66. Further, in the second hot water supply path 66, the first hot water is consumed in the upstream and downstream sides of the connecting portion of the second hot water supply path 66 and the hot water supply bypass path 72 to heat the water in the second hot water supply path 66. A heater 35 is attached. The first hot water supply path 62 and the second hot water supply path 66 communicate with each other through a hot water supply bypass path 72. The hot water supply bypass path 72 is provided with a bypass control valve 34 and a first heater 35 that consumes electric power and heats the water in the hot water supply bypass path 72.

  The tank unit 6 further includes a tank controller 74 and a remote controller 76 that can communicate with the tank controller 74. The tank controller 74 controls the operation of each component of the tank unit 6. The tank controller 74 includes a nonvolatile memory 75. The remote control 76 accepts various operation inputs from the user via switches, buttons, and the like. In addition, the remote controller 76 notifies the user of various types of information related to the settings and operations of the hot water supply system 2 by display and sound.

  The burner unit 8 includes a burner 80, a heat exchanger 82, a bypass servo 84, a water amount servo 86, a hot water valve 88, and a burner outside air temperature thermistor 85 that detects the outside air temperature. The burner 80 is an auxiliary heat source machine that heats water flowing through the heat exchanger 82 by combustion of fuel gas. Fuel gas is supplied to the burner 80 via a gas supply pipe 81. Water from the first hot water supply path 62 of the tank unit 6 flows into the heat exchanger 82 via the burner forward path 90. The water that has passed through the heat exchanger 82 flows out to the second hot water supply path 66 of the tank unit 6 through the burner return path 92. The burner forward path 90 includes a second heater 83 that consumes electric power to heat the water in the burner forward path 90, a water amount servo 86 that adjusts the flow rate of water flowing through the burner forward path 90, and the flow rate of water flowing through the burner forward path 90. A water amount sensor 91 is attached to detect this. The burner forward path 90 and the burner return path 92 communicate with each other via a burner bypass path 94. A second heater 83 that consumes electric power and heats the water in the burner bypass path 94 is attached to the burner bypass path 94. A bypass servo 84 is attached to a connection portion between the burner forward path 90 and the burner bypass path 94. The bypass servo 84 adjusts the flow rate of water flowing from the burner forward path 90 to the burner bypass path 94. A burner hot water thermistor 96 that detects the temperature of water flowing out from the heat exchanger 82 is attached to the burner return path 92. A hot water path 98 branches off from the burner return path 92. In the burner return path 92, a second heater 83 that consumes electric power and heats the water in the burner return path 92 is attached to the downstream side of the branch portion of the hot water path 98. In the burner return path 92, a hot water valve 88 and a second heater 83 that consumes electric power and heats the water in the hot water path 98 are attached to the hot water path 98. Hot water is poured from the burner unit 8 to the bathtub, which is a hot water supply location, via the hot water path 98. The burner unit 8 further includes a burner controller 100 that controls the operation of each component of the burner unit 8.

  Electric power is supplied from the power supply unit 9 to the HP unit 4, the tank unit 6, and the burner unit 8 of the hot water supply system 2. The power supply unit 9 includes a distribution board 102, a storage battery 104, and a switch 106. The distribution board 102 is connected to a commercial power source 108, and distributes and supplies power supplied from the commercial power source 108 to the switch 106 and the storage battery 104. The storage battery 104 is a secondary battery such as a lithium ion secondary battery. The storage battery 104 can charge the power supplied from the commercial power supply 108 via the distribution board 102, and can discharge the charged power to the switch 106. The storage battery 104 has a built-in protection circuit (not shown), and discharge to the switch 106 is cut off when the electric power to be discharged is equal to or higher than the upper limit discharge electric power (for example, 720 W). The switch 106 supplies power supplied from the commercial power source 108 via the distribution board 102 to the HP unit 4, the tank unit 6 and the burner unit 8, and supplies power supplied from the storage battery 104 to the HP unit 4, The state is switched between the states supplied to the tank unit 6 and the burner unit 8. In a situation where the power supply from the commercial power source 108 is normally performed, the switch 106 supplies the power supplied from the commercial power source 108 via the distribution board 102 to the HP unit 4, the tank unit 6, and the burner unit 8. Supply. In a situation where the power supply from the commercial power supply 108 is not normally performed, the switch 106 supplies the power supplied from the storage battery 104 to the HP unit 4, the tank unit 6 and the burner unit 8. Hereinafter, a state where the power supply source is the commercial power supply 108 is referred to as “normal operation”, and a state where the power supply source is supplied with power from the storage battery 104 is referred to as “power suppression operation”. In the power suppression operation, the hot water supply system 2 operates at a suppression power (for example, 700 W) or less that is lower than the maximum power consumption during normal operation.

  The HP controller 24 and the tank controller 74 can communicate with each other. The tank controller 74 and the burner controller 100 can communicate with each other. Therefore, when the HP controller 24, the tank controller 74, and the burner controller 100 perform the control in cooperation, the hot water supply system 2 can perform various operations such as an antifreezing operation, a heating operation, and a hot water supply operation. In addition, the nonvolatile memory 75 stores a scheduled heating start time and a driving flag for the heating process. Hereinafter, the HP controller 24, the tank controller 74, and the burner controller 100 are collectively referred to simply as a controller.

  Next, the operation of the hot water supply system 2 will be described. The hot water supply system 2 can perform a freeze prevention operation, a heating operation, and a hot water supply operation.

(Anti-freezing operation)
The freeze prevention operation will be described with reference to FIG. When a long time elapses without performing heating operation or hot water supply operation in a state where the outside air temperature is low, water in each path may stay and the water may freeze inside these pipes. If the water freezes, the heating operation and the hot water supply operation cannot be performed until the frozen water is melted. For this reason, the hot water supply system 2 of a present Example performs anti-freezing operation so that the water in each length does not freeze. The freeze prevention operation includes a first freeze prevention operation executed by the tank controller 74 and a second freeze prevention operation executed by the burner controller 100.

  The tank controller 74 performs the first freeze prevention operation when the outside air temperature detected by the tank outside air temperature thermistor 39 is equal to or lower than the first predetermined temperature. In the first freeze prevention operation, the tank controller 74 switches between driving and non-driving of the plurality of first heaters 35 according to the first predetermined cycle. The tank controller 74 drives the plurality of first heaters 35 to heat the flow path through which water flows in the tank unit 6, and prevents water from freezing inside these pipes. Note that the driving time and non-driving time of the plurality of first heaters 35 in the first predetermined cycle are determined based on the outside air temperature. Hereinafter, in the first freeze prevention operation, the case where the plurality of first heaters 35 are driven is referred to as “first drive operation”, and the case where the plurality of first heaters 35 are not driven (not driven) is referred to as “first drive operation”. This is called “1 non-driving operation”.

  The burner controller 100 performs the second freeze prevention operation when the outside air temperature detected by the burner outside air temperature thermistor 85 is equal to or lower than the second predetermined temperature. In the second anti-freezing operation, the burner controller 100 switches driving / non-driving of the plurality of second heaters 83 according to the second predetermined cycle. The burner controller 100 drives the plurality of second heaters 83 to heat the flow path through which the water flows in the burner unit 8, and prevents the water from freezing inside these pipes. Note that the driving time and non-driving time of the plurality of second heaters 83 in the second predetermined cycle are changed based on the outside air temperature. Hereinafter, in the second freeze prevention operation, the case where the plurality of second heaters 83 are driven is referred to as “second drive operation”, and the case where the plurality of second heaters 83 are not driven (non-drive) is referred to as “second drive”. This is called “2 non-driving operation”. The case where at least one of the first drive operation and the second drive operation is being executed is referred to as “heater drive operation”, and the case where both the first drive operation and the second drive operation are not being executed is referred to as “heater non-drive”. Called “driving”.

  In the normal operation, the tank controller 74 and the burner controller 100 independently control the first antifreeze operation and the second antifreeze operation (FIG. 2A). That is, the tank controller 74 performs the first freeze prevention operation according to the first predetermined cycle, and the burner controller 100 executes the second freeze prevention operation according to the second predetermined cycle. For this reason, in normal operation, the state in which the first drive operation and the second drive operation are performed simultaneously (heater drive operation) and the state in which only one of the first drive operation and the second drive operation is performed ( (Heater driving operation) and a state where both the first driving operation and the second driving operation are not executed (heater non-driving operation).

  In the power suppression operation, when only the first anti-freezing operation is executed, the tank controller 74 operates the plurality of first heaters 35 according to the first predetermined period. On the other hand, when the first anti-freezing operation and the second anti-freezing operation are simultaneously performed in the power suppression operation, the tank controller 74 controls the first anti-freezing operation in cooperation with the second anti-freezing operation (FIG. 2). (B)). The tank controller 74 receives the second predetermined period from the burner controller 100, and thereby coordinates the first antifreeze operation with the second antifreeze operation. The tank controller 74 adjusts the execution timing of the first driving operation and the first non-driving operation of the plurality of first heaters 35 based on the received second predetermined cycle. Specifically, the tank controller 74 performs the first drive operation of the plurality of first heaters 35 during the second drive operation of the plurality of second heaters 83, and the plurality of second heaters 83 perform the second non-drive operation. In the middle, the plurality of first heaters 35 are controlled to the first non-driving operation. On the other hand, the burner controller 100 operates the plurality of second heaters 83 according to the second predetermined cycle. Thereby, when driving the plurality of first heaters 35 and the plurality of second heaters 83, the time for the first drive operation of the plurality of first heaters 35 and the time for the second drive operation of the plurality of second heaters 83 are set. overlap. Further, the first drive operation of the plurality of first heaters 35 is not executed while the plurality of second heaters 83 are in the non-drive operation.

  As described above, the usable power consumption of the hot water supply system 2 is suppressed below the suppressed power during the power suppression operation. When the heater driving operation and the heating operation are performed at the same time, there is a possibility that the suppression power is exceeded. For this reason, in the power suppression operation, it is necessary to lengthen the heater non-drive time in order to ensure a time during which the heating operation can be performed. In the case of normal operation, the second or first drive operation may be executed during the first or second non-drive operation. On the other hand, during the power suppression operation, the second drive operation is not performed during the first or second non-drive operation by synchronizing the first drive operation and the second drive operation. For this reason, the heater non-driving operation time in the power suppression operation can be made longer than the heater non-driving operation time in the normal operation. Thereby, the time which can perform heating operation can be ensured in electric power suppression operation.

  During the heater driving operation, a driving flag is stored in the nonvolatile memory 75. The drive flag stored in the non-volatile memory 75 is deleted when the heater drive operation is switched to the heater non-drive operation. Further, the time for the first drive operation during the power suppression operation is set longer than the time for the first drive operation during the normal operation. This is because the first driving operation and the second driving operation are synchronized, so that the non-driving time of the plurality of first heaters 35 (time of the first non-driving operation) or the non-driving time of the plurality of second heaters 83 ( This is because the second non-driving operation time) may become longer.

(Heating operation)
In the heating operation, the hot water supply system 2 drives the HP unit 4 to heat the water in the tank 30. The heating operation is configured by a low temperature heating operation in which the target temperature TA after heating by the HP unit 4 is the low temperature target temperature TL and a high temperature heating operation in which the target temperature TA after heating by the HP unit 4 is the high temperature target temperature TH. Yes. The low temperature heating operation heats the water in the tank 30 for use in hot water supply to the hot water supply location. For this reason, the low temperature target temperature TL in the low temperature heating operation is set to a temperature suitable for hot water supply (for example, 45 ° C.). The high temperature heating operation heats the water in the tank 30 in order to sterilize fungi (such as Legionella bacteria) that may propagate in the water in the tank 30. In general, when the water in the tank 30 stays at a low temperature (for example, a temperature of 60 ° C. or lower) for a long time (for example, 96 hours), there is a possibility that fungi (Legionella bacteria, etc.) may propagate. For this reason, the high temperature target temperature TH in the high temperature heating operation is set to a temperature (for example, 65 ° C.) sufficient to sterilize fungi (eg, Legionella). Thereby, it is possible to prevent hot water from being supplied with water in which fungi may be propagated. Since the high temperature target temperature TH is higher than the low temperature target temperature TL, the power consumption of the HP unit 4 during the high temperature heating operation is larger than the power consumption during the low temperature heating operation.

  When the heating operation is started, the HP controller 24 drives the compressor 10 to circulate the refrigerant in the order of the compressor 10, the condenser 12, the expansion valve 14, and the evaporator 16, and drives the circulation pump 18. Then, water is circulated between the tank 30 and the condenser 12. As a result, the water sucked from the bottom of the tank 30 is heated to the boiling temperature in the condenser 12 and returned to the top of the tank 30. When the predetermined amount of water in the tank 30 is replaced with water heated to the boiling temperature, the HP controller 24 ends the heating operation.

(Hot water operation)
In the hot water supply operation, water at a hot water supply set temperature is supplied to the hot water supply location. When the flow rate detected by the water-side water amount sensor 54 and the flow rate detected by the hot water-side water amount sensor 60 (referred to as a hot water supply flow rate) is equal to or greater than the minimum operating flow rate (for example, 2.4 L / min). It is determined that the hot water supply has been started by opening the hot water supply location or hot water to the bathtub. Then, the controller executes the following non-combustion hot water supply operation or combustion hot water supply operation in accordance with the temperature detected by the upper thermistor 36.

  When the temperature detected by the upper thermistor 36 is equal to or higher than the hot water supply set temperature, the controller performs a non-combustion hot water supply operation. In the non-combustion hot water supply operation, the controller prohibits the combustion operation of the burner 80 and adjusts the opening of the mixing valve 32 so that the temperature detected by the mixing thermistor 64 becomes the hot water supply set temperature. Thus, water whose temperature is adjusted to the hot water supply set temperature is supplied to the hot water supply location.

  When the temperature detected by the upper thermistor 36 is lower than the hot water supply set temperature, the controller executes the combustion hot water supply operation. In the combustion hot water supply operation, the controller permits the burner 80 to perform the combustion operation, and mixes so that the temperature detected by the mixing thermistor 64 is lower than the hot water supply set temperature by the minimum heating capacity of the burner 80. The opening degree of the valve 32 is adjusted. In this case, the high temperature water supplied from the upper part of the tank 30 and the low temperature water supplied from the water supply path 40 are mixed in the mixing valve 32 and then heated to the hot water supply set temperature by the burner 80, so Supplied to.

  If the hot water flow rate falls below the minimum operating flow rate during the non-combustion hot water supply operation or combustion hot water supply operation described above, the controller determines that the hot water supply has been terminated due to the closure of the hot water supply location or the end of hot water to the bathtub. To end the hot water supply operation.

(Heat treatment)
Next, the heat treatment during the power suppression operation will be described with reference to FIGS. The heating process is a process for executing a heating operation. The tank controller 74 starts the process of FIG. 6 when the scheduled heating start time stored in the nonvolatile memory 75 arrives. First, a method for specifying the scheduled heating start time stored in the nonvolatile memory 75 will be described.

  Regarding the scheduled heating start time when the high temperature heating operation is performed, the tank controller 74 stores in the nonvolatile memory 75 the scheduled high temperature heating start time after a predetermined period (for example, 96 hours) has elapsed since the previous high temperature heating operation.

  Regarding the scheduled heating start time when the low temperature heating operation is performed, the scheduled heating start time is specified according to the past use history of hot water supply. With reference to FIG. 3, the specification of the scheduled heating start time when the low temperature heating operation is performed will be described. First, the tank controller 74 specifies the scheduled heating start time based on the hot water supply tendency of a specific household. Specifically, the tank controller 74 sets time information indicating the time at which hot water supply is started and the time at which hot water supply is ended each time hot water is supplied in a specific household, and the amount of supplied water. Supply amount information to be stored. The tank controller 74 stores time information and supply amount information for one day as an operation history for one day for a specific household. In this embodiment, the tank controller 74 stores the operation history for the past seven days of a specific household. For this reason, the tank controller 74 erases the operation history of 8 days ago every 24 hours and stores the operation history of the previous day.

  Next, the tank controller 74 specifies the earliest time among the times when the first hot water supply is started in the past seven days from the operation history for the past seven days of the specific household. Hereinafter, this time is referred to as “hot water supply start time S1”. For example, the tank controller 74 specifies 6:00 as the hot water supply start time S1 (see FIG. 3). In the first hot water supply, about 5 L to 20 L of water is supplied.

  Moreover, the tank controller 74 specifies the earliest time among the times when the hot water filling operation is started in the past seven days from the operation history of the specific household for the past seven days. Hereinafter, this time is referred to as “hot water start time B1”. As described above, in this embodiment, a specific household is set in advance to start a hot water filling operation at 20:00 every day. For example, the tank controller 74 specifies 20:00 as the hot water start time B1 (see FIG. 3). In the hot water operation, about 150 L to 180 L of water is supplied.

  Furthermore, the tank controller 74 specifies the latest time among the times when the last hot water supply has ended in the past seven days from the operation history for the past seven days of the specific household. Hereinafter, this time is referred to as “hot water supply end time G1”. For example, the tank controller 74 specifies 0:00 as the hot water supply end time G1 (see FIG. 3).

  Furthermore, the tank controller 74 specifies the first predetermined time α, the second predetermined time β, and the third predetermined time γ based on the feed water temperature TW measured by the incoming water thermistor 44.

  Next, the tank controller 74 specifies the first heating start scheduled time S0 that is a time before the specified first predetermined time α from the hot water supply start time S1, and specifies the specified first from the hot water start time B1. The second heating start scheduled time B0, which is a time before the predetermined time β of 2, is specified. That is, the tank controller 74 stores the first heating start scheduled time S0 and the second heating start scheduled time B0 in the nonvolatile memory 75 as the scheduled heating start time. By doing in this way, the amount of heated water required before the hot water supply is started can be prepared in the tank 30. Further, in the high temperature heating operation, fungi that may be propagated in the water in the tank 30 can be sterilized.

  Further, when the freeze prevention operation is being executed during the power suppression operation, the tank controller 74 may advance the scheduled heating start time based on the scheduled heating start time and the heater driving operation stored in the nonvolatile memory 75. There is. A process for advancing the scheduled heating start time when the freeze prevention operation is being executed during the power suppression operation will be described with reference to FIG. FIG. 4 shows a case where the first anti-freezing operation and the second anti-freezing operation are being executed. Note that the first driving operation of the first heater 35 is omitted for easy viewing.

  First, the tank controller 74 receives a second predetermined cycle from the burner controller 100. Next, the tank controller 74 specifies the drive start time D0 of the second freeze prevention operation based on the second predetermined cycle. When the drive start time D0 is between the first heating start scheduled time S0 and the hot water supply start time S1 (that is, in the present embodiment, approximately the same time as the end of the first heating operation), the tank controller 74 is The fourth predetermined time x is specified. The fourth predetermined time x is a time obtained by subtracting the drive start time D0 from the hot water supply start time S1. Next, the tank controller 74 specifies a first heating start scheduled time S0 ′ that is a time that is a fourth predetermined time x before the first heating start scheduled time S0. Next, the tank controller 74 overwrites and saves the first heating start scheduled time S0 stored in the nonvolatile memory 75 to the first heating start scheduled time S0 '. Thus, the heating operation can be completed before the freeze prevention operation is executed. If the heating operation and the freeze prevention operation are simultaneously performed during the power suppression operation, the power consumption of the hot water supply system 2 exceeds the suppression power. For this reason, when the heating operation is not completed before the freeze prevention operation is executed, the heating operation must be interrupted or the start of the freeze prevention operation must be delayed. By delaying the first heating start scheduled time S0 to the first heating start scheduled time S0 ′ based on the drive start time D0, it is possible to prevent the heating operation from being interrupted or the freeze prevention operation from being delayed. In addition, when the freeze prevention operation is performed during the power suppression operation, the tank controller 74 performs the same processing for the second heating start scheduled time B0 and the high temperature heating scheduled start time. In the present embodiment, the hot water supply start time S1 and the end time of the heating operation are the same, but the heating operation is performed before the hot water supply start time S1 within a range in which heat release of the water heated by the heating operation can be allowed. You may make it complete | finish. In this case, the fourth predetermined time x is a time obtained by subtracting the drive start time D0 from the end time of the heating operation.

  A heating process performed by the tank controller 74 in the power suppression operation will be described with reference to FIGS. As described above, the non-volatile memory 75 stores the high temperature heating start scheduled time, the first heating start scheduled time, and the second heating start scheduled time as the scheduled heating start time. The tank controller 74 starts the heating process when any scheduled start time stored in the nonvolatile memory 75 arrives. In the power suppression operation, if the heating operation and the heater drive operation are performed simultaneously, the power consumption of the hot water supply system 2 exceeds the suppression power. For this reason, the heat treatment is configured such that the heating operation and the heater driving operation are not performed simultaneously.

  First, in step S2, the tank controller 74 determines whether or not the drive flag has been deleted. If the drive flag has been deleted (YES in step S2), the tank controller 74 proceeds to step S4. If the drive flag has not been erased (NO in step S2), the tank controller 74 proceeds to step S8.

  The case where the drive flag is erased (YES in step S2) is a case where the heater drive operation is not executed. In this case, in step S4, the tank controller 74 determines whether or not the temperature detected by the thermistor is equal to or higher than the target temperature TA. In addition, the thermistor used for determination of target temperature TA changes according to the target heating amount at the time of heating operation. For example, when the heating amount required by the hot water supply start time S1 is 5 L to 20 L, the lower thermistor 38 is used. As described above, the temperature of the water in the tank 30 is higher at the upper part of the tank 30 than at the lower part of the tank 30. For this reason, by using the lower thermistor 38 disposed 30 liters from the top of the tank 30, it is determined that 5L to 20L or more of water heated to the target temperature TA or higher is stored in the tank 30. it can. In addition, when the necessary heating amount is 100 L (that is, in the full storage state), the return thermistor 20 is used for determination. When the temperature of the water in the tank 30 exceeds the target temperature TA (YES in step S4), the controller proceeds to step S6 and stops the HP unit 4. On the other hand, when the temperature of the water in the tank 30 does not exceed the target temperature TA (NO in step S4), the tank controller 74 proceeds to step S10 and drives the HP unit 4 (heating operation). The tank controller 74 continues the heating operation until the temperature of the water in the tank 30 exceeds the target temperature TA. If the temperature of the water in the tank 30 exceeds the target temperature TA, the tank controller 74 stops the HP unit 4 and performs the heating operation. Exit.

  The case where the drive flag is not erased (NO in step S2) is, for example, the case where the freeze prevention operation (specifically, the heater drive operation) is started during the execution of the heating operation. That is, this is a case where the start condition for the freeze prevention operation is satisfied during the execution of the heating operation. The processing of the tank controller 74 in this case will be described with reference to FIGS. In FIG. 6, the heat treatment is started by the arrival of the first heating start scheduled time S0. Note that when the start condition of the freeze prevention operation is satisfied, first, the heater driving operation is executed.

  In FIG. 5, when the first heating start scheduled time S0 comes, the tank controller 74 determines YES in step S2, determines NO in step S4, and drives the HP unit 4 in step S10. When the drive start time D1 arrives and the start condition for the freeze prevention operation is satisfied, the heater drive operation is executed. For this reason, the drive flag is stored in the nonvolatile memory 75. In this case, the tank controller 74 determines NO in step S2, and stops driving the HP unit 4 (step S8). In the power suppression operation, if the heating operation and the heater drive operation are executed simultaneously, the power consumption of the hot water supply system 2 exceeds the suppression power. For this reason, the tank controller 74 must delay the start of the heater driving operation or stop the heating operation before the heating operation is completed. When the heating operation is continued and the start of the heater driving operation is delayed until the heating operation is completed, water in each path to which the plurality of first heaters 35 or the plurality of second heaters 83 are attached is frozen. there is a possibility. For this reason, in this embodiment, the HP unit 4 is stopped at the drive start time D1 when the start condition of the freeze prevention operation is satisfied (FIG. 6) (step S8). That is, the heating operation is interrupted and the heater driving operation is preferentially executed. By performing the heater driving operation, it is possible to appropriately prevent freezing of water in each path. On the other hand, the heating operation is not completed at the drive start time D1. Accordingly, the tank controller 74 waits for the heating operation to resume with the HP unit 4 stopped until the drive flag is cleared. When the drive completion time D2 comes, the heater drive operation is completed and the drive flag is deleted. As a result, the tank controller 74 determines YES in step S2, NO in step S4, restarts the HP unit 4, and restarts the heating operation. The tank controller 74 continues the heating operation until the temperature of the water in the tank 30 exceeds the target temperature TA, and stops the HP unit 4 (step S6). Thus, when the heater driving operation is to be executed during the heating operation, the heater driving operation and the heating operation can be appropriately executed.

  As described above, during the power suppression operation, the power that can be used by the hot water supply system 2 is limited to a suppression power (for example, 700 W) or less. When the heating operation and the freeze prevention operation (specifically, the heater driving operation) are performed at the same time, the suppression power is exceeded and the operation of the hot water supply system 2 is stopped. According to the above configuration, the heating operation and the freeze prevention operation (specifically, the heater driving operation) are not performed simultaneously during the power suppression operation. Thereby, the power consumption of the hot water supply system 2 during the power suppression operation can be suppressed to be equal to or lower than the suppression power, and the freeze prevention operation (specifically, the heater drive operation) can be performed even during the power suppression operation. it can. For this reason, it can prevent that the water in each path | route to which the some 1st heater 35 and the some 2nd heater 83 are attached freezes.

  In the above embodiment, the first drive operation of the first heater 35 is synchronized with the second drive operation of the second heater 83 during the power suppression operation. Thereby, the heater non-driving operation time during the power suppression operation is longer than the heater non-driving operation time during the normal operation. As described above, during the power suppression operation, the heating operation must be performed during the heater non-drive operation. By extending the heater non-driving operation time during the power suppression operation, it is possible to secure a longer time during which the heating operation can be performed.

  In the above-described embodiment, when the heater driving operation is to be executed during the heating operation, the heating operation is stopped and the heater driving operation is executed. According to such a configuration, it is possible to reliably prevent freezing of water in each path to which the plurality of first heaters 35 or the plurality of second heaters 83 are attached, and to reliably complete the heating operation. be able to.

  Further, in the above-described embodiment, when the heater driving operation is to be executed by the end of the heating operation, the scheduled heating start time of the heating operation is advanced. According to such a configuration, when the heater driving operation is to be executed by the end of the heating operation, the heating operation is completed by the scheduled completion time that is initially scheduled without interrupting the heating operation. Can be made.

  Here, the correspondence between the description of the embodiment and the description of the claims will be described. Water is an example of a “heating medium”. A heat pump cycle including the compressor 10, the condenser 12, the expansion valve 14, and the evaporator 16 is an example of the “heat pump heat source”. The burner 80 is an example of an “auxiliary heat source”. The controller is an example of a “control device”. The heater driving operation is an example of the “freezing prevention operation”. The scheduled heating start time is an example of “scheduled start time”.

  Each embodiment has been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  In the above embodiment, the power suppression operation is performed when the power supply source is the storage battery 104. However, the power supply source may be the commercial power supply 108 and may be operated with suppressed power lower than the maximum power consumption during normal operation. For example, when a disaster occurs.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

2: Hot water supply system 4: HP unit 6: Tank unit 8: Burner unit 9: Electric power supply unit 10: Compressor 12: Condenser 14: Expansion valve 16: Evaporator 18: Circulation pump 19: HP forward path 20: Return thermistor 21: HP return path 22: Forward thermistor 23: HP outside temperature thermistor 24: HP controller 30: Tank 31: Tank forward path 32: Mixing valve 33: Tank return path 34: Bypass control valve 35: First heater 36: Upper thermistor 37: Intermediate thermistor 38: Lower thermistor 39: Tank outside temperature thermistor 40: Water supply path 42: Pressure reducing valve 44: Water inlet thermistor 46: Tank water supply path 48: Tank bypass path 50: Check valve 52: Check valve 54: Water Side water amount sensor 56: Tank discharge path 58: Check valve 60: Hot water side water quantity sensor 62: first hot water supply path 64: mixing thermistor 66: second hot water supply path 68: hot water supply outlet thermistor 70: check valve 72: hot water supply bypass path 74: tank controller 75: nonvolatile memory 76: remote controller 80: burner 81: Gas supply pipe 82: Heat exchanger 83: Second heater 84: Bypass servo 85: Burner outside air temperature thermistor 86: Water quantity servo 88: Hot water valve 90: Burner forward path 91: Water quantity sensor 92: Burner return path 94: Burner bypass Path 96: Burner hot water supply thermistor 98: Hot water path 100: Burner controller 102: Distribution board 104: Storage battery 106: Switch 108: Commercial power supply

Claims (4)

A heat pump unit including a heat pump heat source that consumes electric power and heats the heat medium, and a tank unit including a tank that stores a heat medium heated by the heat pump heat source. A thermal device having a power suppression operation that operates below a suppression power lower than the power consumption,
A first heater which is provided in the tank unit and consumes electric power to heat the heat medium in the tank unit;
The control device is configured to be capable of performing a freeze prevention operation for driving the first heater and a heating operation for driving the heat pump heat source and storing the heat medium heated by the heat pump heat source in the tank,
The control device is a thermal device configured to perform a heating operation when the freeze prevention operation is not performed during the power suppression operation. An auxiliary heat source unit including an auxiliary heat source for heating the heat medium by combustion of fuel;
A second heater which is provided in the auxiliary heat source unit and consumes electric power to heat the heat medium in the auxiliary heat source unit;
The control device is configured to drive at least one of the first heater or the second heater in the freeze prevention operation,
When the control device drives both the first heater and the second heater in the anti-freezing operation during the power suppression operation, at least a part of the time for driving the first heater and the time for driving the second heater overlap. The thermal apparatus of claim 1, wherein the antifreezing operation is performed to meet.   When the freeze prevention operation is to be executed during the heating operation during the power suppression operation, the control device stops the heating operation and executes the freeze prevention operation, and resumes the heating operation after the freeze prevention operation is completed. The thermal device according to claim 1 or 2. The control device is configured to set the scheduled start time of the heating operation according to the past use of the heat medium, and to execute the heating operation when the set scheduled start time is reached,
When the heating operation is performed at the set scheduled start time during the power suppression operation, the control device advances the scheduled start time of the heating operation when the anti-freezing operation is performed by the end of the heating operation. The thermal device according to any one of claims 1 to 3.

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