JP2015087054A - Hot water supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water supply device capable of detecting reverse connection in a short time without using a dedicated sensor.SOLUTION: When confirming a connection state between an outgoing pipe 31 for boiling and a returning pipe 32 for boiling, and an inlet pipe 36 and an outlet pipe 37, a control unit operates a heat pump unit 13 and a circulation pump 33 for boiling. Then, a heat storage switching valve 26 is controlled so that a fluid for heat storage passing through the returning pipe 32 for boiling flows into a drawing pipe 41. Thereby, the fluid for heat storage boiled by the heat pump unit 13 flows in the drawing pipe 41, when the connection state is normal. The temperature of the fluid for heat storage passing through the drawing pipe 41 is detected by a bath primary thermistor 45. Then, when the temperature detected by the bath primary thermistor 45 is lower than a predetermined boiling temperature, the control unit determines that the outgoing pipe 31 for boiling and the returning pipe 32 for boiling, and the inlet pipe 36 and the outlet pipe 37 are in a reverse connection state.

Description

  The present invention relates to a hot water supply apparatus using a separate heating unit for boiling hot water stored in a hot water storage tank.

  Conventionally, in a hot water supply apparatus using a heat pump unit for boiling hot water stored in a hot water storage tank, water is taken out from the lower part of the hot water storage tank and heated to a predetermined boiling temperature by the heat pump unit during boiling operation. Then, the hot water boiled by the heat pump unit is circulated by the boiling circulation pump so as to return to the upper part of the hot water storage tank. As a result, the hot water does not mix with the water through a mixed layer of hot water and water formed between the hot water on the upper side and the lower side of the hot water tank due to the specific gravity difference between the hot water and water at different temperatures. Hot water is stored in order from the top in the hot water storage tank.

  The hot water storage tank and the heat pump unit are installed separately, and between them, the elevating piping connecting the lower part of the hot water tank and the heat pump, and the return for boiling connecting the heat pump unit and the upper part of the hot water tank A boiling circuit is configured by connecting pipes. Then, the water in the lower part of the hot water storage tank is circulated in the direction of returning to the upper part of the hot water storage tank through the heat pump unit and the return return pipe through the heat pump unit and the return return pipe for heating by the boiling circulation pump arranged in the heat pump unit. By doing so, normal boiling operation is possible.

  However, when the hot water supply apparatus is installed, there is a case where the piping of the boiling forward piping and the piping of the return piping for boiling are erroneously reversely connected. In the trial operation after installing the hot water supply device, if the heater is connected in reverse, the heat pump unit takes out the water from the upper part of the hot water tank and boiles it up. Cycle to return. Accordingly, the hot water returned to the lower part of the hot water storage tank only warms the water in the hot water storage tank, and hot water having a predetermined boiling temperature cannot be stored in order from the upper side of the hot water storage tank.

  Therefore, as a method for detecting the reverse connection of the boiling forward piping and the boiling return piping, the temperature of the hot water tank is set within a predetermined time by using a water temperature sensor of the hot water tank. There is a method of determining based on whether or not the temperature is reached (see, for example, Patent Document 1).

JP 2005-147616 A

  In the method described in Patent Document 1, when the outside air temperature is low, the temperature rise time at the upper part of the hot water storage tank also becomes long, and therefore a confirmation time of about 60 minutes is usually required to prevent erroneous detection. Accordingly, there is a problem that it takes time to confirm whether or not the vehicle is normally operated even after the construction is completed. Therefore, a technique for detecting reverse connection in a short time is desired.

  As another detection method using a temperature sensor, there is a method in which a bath-side pump is operated to extract hot water from an upper part of a hot water storage tank, and reverse connection is detected by a temperature sensor value at a bath-side heat exchanger outlet. However, when a pipe is once removed and reconnected due to a failure of the heat pump or the like, the hot water storage tank may store heat to some extent. In this case, even if the reverse connection is detected by the temperature sensor at the outlet of the heat exchanger, the hot water storage tank is storing heat, so it cannot be determined whether it is the original heat storage temperature or the normal boiling temperature. The connection cannot be detected.

  There is also a method of detecting reverse connection based on a temperature change in the pipe before heat storage or a temperature change in the pipe connected to the lower part of the hot water storage tank. However, there is a problem that a dedicated temperature sensor for detecting reverse connection is required and the manufacturing cost increases.

  Then, this invention is made | formed in view of the above-mentioned problem, and it aims at providing the hot-water supply apparatus which can detect a reverse connection in a short time, without using a dedicated sensor.

  The present invention employs the following technical means in order to achieve the aforementioned object.

  The present invention relates to a flow rate adjusting means (26, 90) for controlling the flow rate of the heat storage fluid that passes through the boiling return pipe and returns to the upper part of the tank, a heating unit, a flow rate adjusting means, a boiling circulation pump, and heat. A control unit that controls the circulation pump for the load, and the control unit operates the heating unit and the circulation pump for boiling, so that the heat storage fluid that has passed through the return piping for boiling flows into the extraction piping If the temperature of the adjusting means is controlled and the temperature detected by the temperature detecting means is lower than the predetermined boiling temperature, the connection of the boiling forward piping and the boiling return piping to the inlet piping and outlet piping is in a reverse connection state. It is characterized by determining.

  According to the present invention as described above, when the connection state between the boiling forward pipe and the boiling return pipe and the inlet pipe and the outlet pipe is confirmed, the control unit operates the heating unit and the boiling circulation pump. Then, the control unit controls the flow rate adjusting means such that the heat storage fluid that has passed through the boiling return pipe flows into the extraction pipe. Thus, the heat storage fluid boiled up by the heating unit flows through the extraction pipe if the connection state is normal. The temperature of the heat storage fluid that passes through the extraction pipe is detected by the temperature detection means. Therefore, if the temperature detected by the temperature detection means is lower than the predetermined boiling temperature, the control unit determines that the boiling forward piping, the boiling return piping, the inlet piping, and the outlet piping are in a reverse connection state. If the connection state is normal, since the heat storage fluid heated as described above passes through the extraction pipe, the detected temperature should not be lower than the predetermined boiling temperature. If this is lower than the predetermined temperature, the heated heat storage fluid has not passed through the extraction pipe. Therefore, the control unit can determine that the connection is reverse when the temperature is lower than the predetermined temperature. Moreover, since the heat storage fluid heated will flow into extraction piping if it is normal, if the control part implements the control for confirmation, it can determine in a short time whether it is reverse connection.

  Moreover, although a control part determines with it being reverse connection by the temperature which the temperature detection means detected, this temperature detection means is not provided in order to determine reverse connection. The temperature detecting means is provided for controlling the thermal load circuit. Therefore, the temperature detecting means for controlling the heat load circuit is originally used to determine reverse connection. Accordingly, it is possible to realize a hot water supply apparatus that can determine reverse connection in a short time without using a dedicated sensor for determining reverse connection.

  In addition, the code | symbol in the bracket | parenthesis of each above-mentioned means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is the figure which showed the piping structure of the hot water supply apparatus 10 of 1st Embodiment. 4 is a graph showing a temperature change of a heat storage fluid in the hot water storage tank 11. It is a flowchart which shows the process of a control part. It is the figure which showed the piping structure of 10 A of hot water supply apparatuses of 2nd Embodiment. It is a flowchart which shows the process of a control part.

  Hereinafter, a plurality of embodiments for carrying out the present invention will be described with reference to the drawings. In some embodiments, portions corresponding to the matters described in the preceding embodiments may be given the same reference numerals, or one letter may be added to the preceding reference numerals, and overlapping descriptions may be omitted. In addition, when a part of the configuration is described in each embodiment, the other parts of the configuration are the same as those of the embodiment described in advance. In addition to the combination of parts specifically described in each embodiment, the embodiments may be partially combined as long as the combination does not hinder the combination.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. The hot water supply apparatus 10 of the present embodiment is used for general household use, and uses the heat storage fluid stored in the hot water storage tank 11 as a heat source, in addition to the hot water supply function to the kitchen, washroom, bathroom, etc. It has a function of chasing hot water to the bathtub 51 and bath water filled with hot water. In this embodiment, the same hot water supply water as the hot water supply side is used as the heat storage fluid.

  The hot water supply apparatus 10 includes a hot water storage tank unit 20 and a heat pump unit 13. The hot water storage tank unit 20 includes a hot water storage tank 11, a boiling circuit 12, a heat load circuit 14, a water supply pipe 15, a hot water supply pipe 27, and a control unit (not shown). The hot water storage tank 11 stores a heat storage fluid therein. The hot water storage tank 11 is a container for storing hot water for hot water supply and is made of a metal excellent in corrosion resistance, for example, made of stainless steel. A heat insulating material is provided on the outer periphery thereof, and hot water for hot water supply is provided for a long time. Can keep warm. The hot water storage tank 11 has a vertically long shape, and an introduction port 11a is provided on the bottom surface thereof.

  The hot water storage tank 11 is provided with a water temperature thermistor 11b including seven thermistors arranged in the height direction in order to detect the amount of hot water stored in the hot water storage tank 11 and the hot water storage temperature. The temperature information of hot water or water filled in the hot water storage tank 11 at each water level is output to the control unit. Therefore, the control unit can detect the boundary position between the hot water heated in the upper part of the hot water tank 11 and the water before being heated in the lower part of the hot water tank 11 based on the temperature information from the water temperature thermistor 11b. Thereby, the hot water storage amount can be detected.

  A city water inflow pipe 21 for supplying city water into the hot water storage tank 11 is connected to the introduction port 11 a on the bottom surface of the hot water storage tank 11. The city water pipe 22 connected to the city water inflow pipe 21 is provided with a pressure reducing valve 23 for adjusting the water pressure of the introduced tap water to a predetermined pressure and preventing the backflow of hot water in the case of water interruption. Yes. The city water pipe 22 is connected to a bath mixing valve 24 and a hot water supply mixing valve 25 described later via a water supply pipe 15.

  The heat pump unit 13 is a heating unit that heats the heat storage fluid flowing from the inlet pipe 36 and discharges it to the outlet pipe 37. The heat pump unit 13 has a heat pump cycle that uses carbon dioxide having a low critical temperature as a refrigerant. Accordingly, the heat pump unit 13 is not shown in the drawing, but at least a compressor, a water-refrigerant heat exchanger as a radiator, a variable pressure reducer, an evaporator, and a gas-liquid separator are connected to form a closed circuit. Yes. Further, an evaporator temperature thermistor for detecting the temperature on the downstream side of the evaporator is provided on the downstream side of the evaporator. The control unit receives detection information from the evaporator temperature thermistor and controls the operation of the variable pressure reducer and the compressor.

  The heat pump unit 13 heats up hot water by exchanging heat between the high-temperature and high-pressure refrigerant flowing through the refrigerant flow path of the water-refrigerant heat exchanger and the water flowing through the water flow path of the water-refrigerant heat exchanger. be able to. Moreover, you may comprise the heat pump unit 13 by the ejector-type cycle using an electric ejector.

  When the heat pump cycle is constituted by a supercritical heat pump, hot water having a temperature higher than that of a general heat pump cycle, for example, about 85 ° C. to 90 ° C. can be stored in the hot water storage tank 11. The heat pump cycle mainly uses boiling water to boil the hot water in the hot water storage tank 11 when the hot water stored in the hot water storage tank 11 is insufficient or using late-night power in the late-night time period when the price is set inexpensively. Do the driving.

  The boiling circuit 12 is a circuit for taking out the heat storage fluid from the lower part of the hot water storage tank 11, heating it with the heat pump unit 13, and returning the heat storage fluid to the upper part of the hot water storage tank 11 again. The boiling circuit 12 connects the lower part of the hot water tank 11 and the inlet pipe 36 of the heat pump unit 13, and the boiling pipe 31 connects the outlet pipe 37 of the heat pump unit 13 and the upper part of the hot water tank 11. A return pipe 32 is provided. The boiling circuit 12 also transfers the heat storage fluid in the lower part of the hot water storage tank 11 from the boiling forward piping 31 to the hot water storage tank 11 via the inlet piping 36, the outlet piping 37 and the boiling return piping 32 of the heat pump unit 13. It has a boiling circulation pump 33 that circulates in the direction of returning to the upper part. Further, a bypass valve 34 is provided in the return pipe 32 for boiling. The bypass valve 34 is provided with a bypass pipe 35 that connects the boiling return pipe 32 and the lower part of the hot water storage tank 11. The bypass valve 34 adjusts a flow rate ratio between a flow rate passing through the boiling return pipe 32 and flowing toward the upper portion of the hot water storage tank 11 and a flow rate passing through the bypass pipe 35 and flowing into the lower portion of the hot water storage tank 11.

  The heat load circuit 14 is a circuit for exchanging heat between the heat storage fluid in the hot water storage tank 11 and the hot water in the bathtub 51 in order to replenish the hot water in the bathtub 51 in the bath. The thermal load circuit 14 includes an extraction pipe 41, a bath heat exchanger 42, an intake pipe 43, a bath primary pump 44, a bath primary thermistor 45, and a bath primary check valve 46. The extraction pipe 41 is connected to the upper part of the hot water storage tank 11 and the return pipe 32 for boiling. The bath heat exchanger 42 exchanges heat between the heat storage fluid that has passed through the extraction pipe 41 and the bath side (heat load side). Specifically, the bath heat exchanger 42 is configured to adjoin a first circulation part 42a through which heat storage fluid in the hot water storage tank 11 circulates and a second circulation part 42b through which bath water circulates. And the bath heat exchanger 42 is comprised so that the fluid for thermal storage and bathtub water may become a counterflow, and heat exchange is performed between both. The intake pipe 43 returns the heat storage fluid that has passed through the bath heat exchanger 42 to the hot water storage tank 11. The bath primary pump 44 is a heat load circulation pump that circulates the heat storage fluid of the hot water storage tank 11 from the extraction pipe 41 to the hot water storage tank 11 through the bath heat exchanger 42 and the intake pipe 43. . The bath primary thermistor 45 is temperature detecting means for detecting the temperature of the heat storage fluid that passes through the extraction pipe 41. The bath primary check valve 46 is provided in the intake pipe 43 so that the heat storage fluid in the hot water storage tank 11 does not convect to the hot water storage tank 11 via the bath heat exchanger 42 and the intake pipe 43. It is provided to prevent using the spring force of the check valve.

  A heat storage switching valve 26 is provided at the connection between the boiling circuit 12 and the thermal load circuit 14. The heat storage switching valve 26 is a flow rate adjusting means for adjusting a flow rate ratio between the flow rate that passes through the boiling return pipe 32 and returns to the hot water storage tank 11 and the flow rate that passes through the boiling return pipe 32 and flows to the take-out pipe 41. It is. Further, the heat storage switching valve 26 adjusts the flow rate ratio between the flow rate taken out from the hot water storage tank 11 and flowing into the take-out piping 41 and the flow rate passing through the boiling return pipe 32 and flowing into the take-out piping 41.

  At the upper part of the hot water storage tank 11, a hot water supply pipe 27 is provided in which hot water from the high temperature water section in the hot water storage tank 11 flows out to the hot water use side terminal. The hot water supply pipe 27 communicates with a shower 54, a currant, a hand-washer, etc., and the pipe that branches off in the middle is a bath pipe 28 that communicates with the bath tub 51.

  A discharge pipe 53 provided with a relief valve 52 is connected in the middle of the hot water supply pipe 27. When the pressure in the hot water storage tank 11 rises above a predetermined pressure, the hot water in the hot water storage tank 11 is discharged. It is configured so as not to discharge to the outside and damage the hot water storage tank 11 and the like.

  A city water inflow pipe 21 branched from a city water pipe 22 for taking in city water such as tap water is connected to the lower part of the hot water storage tank 11. The hot water supply pipe 27 is connected with a water supply pipe 15 that communicates with the city water pipe 22.

  The intermediate hot water portion, which is an almost intermediate portion in the hot water storage tank 11, communicates with the intermediate hot water pipe 29 for deriving the intermediate hot water out of the hot water for hot water stored in the hot water storage tank 11. An intermediate temperature water mixing valve 30 is provided at the junction of the hot water supply pipe 27 and the intermediate temperature water pipe 29. The intermediate temperature water mixing valve 30 is a temperature adjustment valve that adjusts the hot water temperature of the hot water supply water. By adjusting the ratio of the respective opening areas, the intermediate temperature water extracted from the hot water supply pipe 27 and the intermediate temperature water extracted from the intermediate temperature water pipe 29 are used. The mixing ratio can be adjusted. Further, the intermediate warm water pipe 29 is provided with an intermediate warm water check valve 17. The intermediate temperature water check valve 17 is provided to prevent the high temperature water at the upper part of the hot water storage tank 11 from passing through the intermediate temperature water mixing valve 30 and backflowing to the intermediate temperature water portion of the hot water storage tank 11.

  A hot water supply pipe 27 and a branched bath pipe 28 are connected to a downstream portion of the intermediate temperature water mixing valve 30. A hot water supply mixing valve 25 is provided in the hot water supply piping 27 on the downstream side of the intermediate temperature water mixing valve 30, and a bath mixing valve 24 is provided in the bath piping 28. The hot water supply mixing valve 25 is provided at a junction between the hot water supply pipe 27 and the water supply pipe 15. The bath mixing valve 24 is provided at the junction of the bath pipe 28 and the water supply pipe 15. The hot water supply mixing valve 25 and the bath mixing valve 24 are temperature control valves that adjust the temperature of hot water for hot water discharged from the ends of the hot water supply pipe 27 and the bath pipe 28, respectively. These are discharged by adjusting the ratio of the respective opening areas, that is, the ratio of the opening degree on the hot water supply water side adjusted in temperature by the intermediate temperature water mixing valve 30 and the opening degree on the water side communicating with the city water pipe 22. Adjust the hot water temperature to the set temperature.

  A hot water supply thermistor 61, a hot water flow rate counter 62, and a hot water check valve 63 are provided in the hot water supply pipe 27 on the downstream side of the hot water mixing valve 25. The hot water supply thermistor 61 detects the temperature of the hot water flowing through the hot water supply pipe 27. The hot water flow rate counter 62 detects the flow rate of hot water flowing through the hot water supply pipe 27. The hot water check valve 63 is provided so as not to flow backward from the shower 54 at the end of the hot water supply pipe 27 to the hot water mixing valve 25.

  The bath piping 28 on the downstream side of the bath mixing valve 24 is provided with a bath pouring unit 70 for pouring the bath. The bath pouring unit 70 includes a bath solenoid valve 71, a backflow prevention valve 72, a bath thermistor 73, a bath flow counter 74, and two bath check valves 75. The bath thermistor 73 detects the temperature of the hot water flowing through the bath pipe 28. The bath flow rate counter 74 detects the flow rate of hot water flowing through the bath piping 28. The two check valves 75 for bath are provided to prevent the bath water in the bath water circulation circuit 80 from flowing back to the bath mixing valve 24.

  Between the two check valves 75 for bath, a check valve 72 having an upstream end connected to the discharge path and a pressure guiding pipe connected downstream of the bath mixing valve 24 is provided. The backflow prevention valve 72 can be discharged to the outside of the bath pouring unit 70 by operating the backflow prevention valve 72 according to the pressure difference between the two connection points when there is bath water to enter the hot water supply pipe 27 side. It is like that.

  The bath solenoid valve 71 is opened when the bathtub 51 is filled with hot water, hot water, and hot water. The bath solenoid valve 71 is controlled so that the mixed hot water having a predetermined flow rate is discharged based on the flow rate information detected by the bath flow rate counter 74.

  The hot water mixing valve 25 and the bath mixing valve 24 are feedback-controlled based on the hot water temperature of the hot water detected by the thermistors 61 and 73 provided on the respective outlet sides. When each flow counter 62, 74 detects the flow of water in the hot water supply pipe 27 and bath pipe 28, the hot water tap, shower 54 or bath solenoid valve 71 at the end of each pipe opens. The hot water supply water is being discharged.

  A bath water circulation circuit 80 for circulating bath water in the bathtub 51 is connected to the bathtub 51. The bath water circulation circuit 80 circulates the bath water to the bath heat exchanger 42 for exchanging heat with the heat load circuit 14 that circulates hot water in the hot water storage tank 11. The bath water circulation circuit 80 includes a bath outlet pipe 81 that guides the bath water in the bathtub 51 to the upstream end of the bath heat exchanger 42, and a bath return pipe that guides the bath water exchanged by the bath heat exchanger 42 into the bathtub 51. 82.

  The bath return pipe 81 is provided with a bath circulation sensor 83, a bath reheating thermistor 85, and a bath circulation pump 84 in order from the upstream side. The bath return pipe 82 is provided with a bath heat exchange thermistor 86. The bath circulation sensor 83 is a sensor for detecting whether or not bath water is flowing in the direction toward the bath heat exchanger 42 of the bath outlet pipe 81. The bath chasing thermistor 85 detects the bath water temperature of the bathtub 51. The bath circulation pump 84 is a pump that circulates the bath water in the bathtub 51 in a direction to return the bath water from the bath outlet pipe 81 to the bathtub 51 via the bath heat exchanger 42 and the bath return pipe 82. The bath heat exchanger thermistor 86 detects the outlet temperature of the bath heat exchanger 42. Further, the downstream end of the bath pipe 28 is connected to a bath outlet pipe 81 between the bath circulation pump 84 and the bath heat exchanger 42.

  The control unit is composed mainly of a microcomputer, and a ROM or RAM built in as storage means is provided with a preset control program or an updatable control program. The control unit is based on temperature information from each thermistor, flow information from each flow counter and running water switch, operation signals from operation switches such as a kitchen remote control (not shown) and a bath remote control (not shown), and the like. The actuators such as the heat pump unit 13, each mixing valve, the electromagnetic valve, the switching valve, and the bath circulation pump 84 are controlled. Therefore, the operation switch is used to operate the heat pump unit 13, the heat storage switching valve 26, the boiling circulation pump 33, and the bath primary pump 44.

  Next, the operation of the hot water supply apparatus 10 will be described. First, the hot water storage operation of the hot water storage tank 11 using the heat pump unit 13 will be described. Here, it is assumed that the boiling forward piping 31 and the boiling return piping 32 of the boiling circuit 12 are normally connected.

  The heat pump unit 13 is operated as a specific boiling time zone, for example, in the nighttime zone of the hourly lighting system. By operating the heat pump unit 13, the water in the lower part of the hot water storage tank 11 is boiled up to a predetermined boiling temperature and returned to the upper part of the hot water storage tank 11. Store hot water for minutes.

  Next, the hot water supply operation will be described. By opening a hot water tap or the like disposed on the downstream side of the hot water supply pipe 27, hot water in the hot water storage tank 11 is pushed out by the water supply pressure, and hot water from the hot water storage tank 11 and water from the city water inflow pipe 21 through each pipe. Are mixed with each mixing valve 24, 25, 30 and hot water is supplied.

  Next, utilization of the bathtub 51 will be described. When filling the bathtub 51 with hot water, the hot water in the hot water storage tank 11 is pushed out by the water supply pressure by opening the solenoid valve 71 for bath, and hot water from the hot water storage tank 11 and the city water inflow pipe 21 are supplied through the hot water supply pipe 27. The water is mixed with the bath mixing valve 24 to obtain hot water at a preset temperature. Then, this hot water is supplied and supplied to the bathtub 51 through the bath water circulation circuit 80. Then, after filling the bathtub 51, the bath circulation pump 84 is operated every predetermined time to circulate the bathtub water in the bathtub 51 in the bath water circulation circuit 80, and the temperature of the bath water is adjusted by the bath reheating thermistor 85. Detect and monitor whether there is a need for heat insulation, that is, a chasing action.

  When the temperature of the bath water drops below the set temperature, the reheating operation is automatically performed, and the reheating operation is also performed by a manual operation such as a remote control. In the reheating operation, first, the bath circulation pump 84 is operated, and the bath water is taken into the bath water circulation circuit 80 and circulated to the bath heat exchanger 42. In this state, by operating the bath primary pump 44, the hot water in the hot water storage tank 11 is taken out through the take-out pipe 41 and sent to the bath heat exchanger 42. Then, heat is exchanged between the hot water from the hot water storage tank 11 and the bath water from the bathtub 51 by the bath heat exchanger 42, and the bath water whose temperature has been raised by this heat exchange is set to a certain temperature or higher by the bath heat exchanger thermistor 86. The number of rotations of the bath primary pump 44 is increased or decreased and returned to the bathtub 51, and the hot water temperature in the bathtub 51 is increased. The hot water taken out to the take-out pipe 41 is taken out by adjusting the mixing ratio between the hot water in the upper part of the hot water storage tank 11 taken out from the take-out pipe 41 and the hot water supplied directly from the heat pump unit 13 by the heat storage switching valve 26. Further, the hot water from the hot water storage tank 11 whose temperature has dropped through the bath heat exchanger 42 is returned to the hot water storage tank 11 through the intake pipe 43.

  Next, determination of whether or not the outlet pipe 37 and the inlet pipe 36 of the boiling circuit 12 are in the reverse connection state will be described with reference to FIGS. 2 and 3. The reverse connection state is a state in which the outlet pipe 37 is connected to the boiling forward pipe 31 and the inlet pipe 36 is erroneously connected to the boiling return pipe 32. In such a reverse connection state, the heat storage fluid in the upper part of the hot water storage tank 11 flows into the inlet pipe 36 via the boiling return pipe 32 of the hot water storage tank 11, and the heated heat storage fluid passes through the outlet pipe 37. , Flows to the boiling forward piping 31. Therefore, in the reverse connection state, the heat storage fluid boiled into the lower portion of the hot water storage tank 11 flows.

  The vertical axis in FIG. 2 is the detected temperature of the water temperature thermistor 11b located at the uppermost position. As shown in FIG. 2, when the boiling forward pipe 31 and the boiling return pipe 32 and the inlet pipe 36 and the outlet pipe 37 are normally connected, the temperature of the heat storage fluid rises smoothly. When the outside temperature in winter is low, the temperature does not rise easily. The comparison between the temperature increase in the reverse connection in summer and the normal connection in winter can be determined only after 45 minutes, for example. Therefore, in this embodiment, in order to detect in a short time, the reverse connection is determined using the bath primary thermistor 45 instead of the water temperature thermistor 11b as shown in the flowchart of FIG. The flowchart shown in FIG. 3 is performed when the hot water supply apparatus 10 is powered on.

  In step S11, it is determined whether or not the operation at the time of construction is performed by operating the operation switch. If it is performed, the process proceeds to step S12, and the process of step S11 is repeated until it is performed.

  In step S12, the bypass valve 34 and the heat storage switching valve 26 are controlled, and the process proceeds to step S13. Specifically, the bypass valve 34 is controlled so that the heat storage fluid from the heat pump unit 13 is directed to the upper part of the hot water storage tank 11. Further, the heat storage switching valve 26 is controlled so that the heat storage fluid from the heat pump unit 13 passes through the bypass valve 34 and goes to the extraction pipe 41. In step S13, the heat pump unit (H / P) 13 is operated to drive the boiling circulation pump 33, and the process proceeds to step S14. As a result, the heat storage fluid in the hot water storage tank 11 is heated. The heated heat storage fluid flows to the extraction pipe 41 via the bypass valve 34 and the heat storage switching valve 26. The heat storage fluid that has flowed through the extraction pipe 41 passes through the bath heat exchanger 42, flows through the intake pipe 43, and is supplied to the hot water storage tank 11.

  In step S14, it is determined whether or not the detected temperature of the bath primary thermistor 45 provided in the intake pipe 43 is equal to or higher than a certain temperature (for example, 50 degrees or higher). If 50 degrees or higher, the process proceeds to step S15. When it is not 50 degrees or more, the process proceeds to step S18. The heat pump unit 13 operates as described above, and the heat storage fluid boiled up by the boiling circulation pump 33 passes through the intake pipe 43. Therefore, if the connection state of the pipe is normal, it is boiled up. The stored heat storage fluid passes through the intake pipe 43. Accordingly, the bath primary thermistor 45 detects a temperature equal to or higher than a certain temperature.

  In step S15, since it is 50 degrees or more, it is determined that the boiling forward piping 31, the boiling return piping 32, the inlet piping 36 and the outlet piping 37 are normally connected, and the heat storage switching valve 26 is turned on. It switches to the hot water storage tank 11 side, and moves to step S16.

  In step S16, the heat pump unit 13 performs boiling control for storing hot water in the hot water storage tank 11, and the process proceeds to step S17. In step S17, it is determined whether or not the hot water storage tank 11 is filled with boiled hot water. If boiling is completed, the process proceeds to step S110, and the control in step S16 is repeated until boiling is completed.

  In step S18, since the detected temperature of the bath primary thermistor 45 is not 50 ° C. or more, it is determined whether or not a predetermined determination condition is satisfied. If the determination condition is satisfied, the process proceeds to step S19, and the determination condition is set. If not, the process returns to step S14. The determination condition is a condition for determining whether the connection is reverse. The determination condition is, for example, whether or not a time less than 50 degrees has passed a predetermined time, whether or not the amount of heat in the hot water storage tank 11 is less than or equal to a predetermined amount of heat, or whether or not the amount of boiling exceeds a predetermined amount. is there. This is because if the predetermined time has not elapsed since the activation of the heat pump unit 13, the heat pump unit 13 may still begin to boil and may be less than 50 degrees. Similarly, when the amount of heat in the hot water storage tank 11 is equal to or less than the predetermined amount of heat, the heat pump unit 13 is still beginning to boil and may be less than 50 degrees. Furthermore, similarly, when a certain amount has not been boiled since the heat pump unit 13 is started, it may be less than 50 degrees to start boiling.

  In step S19, since the determination condition is satisfied, it is determined that the reverse connection state is established, the contractor or the user is notified of the reverse connection, and the process proceeds to step S110. As a result, the contractor or the user can recognize that it is in the reverse connection state.

  In step S110, it is notified that boiling has been completed or reverse connection, so the operation of the heat pump unit 13 is terminated, and the process proceeds to step S111. In step S111, the bypass valve 34 is controlled so that the inflowing heat storage fluid is directed from the bypass valve 34 to the lower part of the hot water storage tank 11, and this flow is ended.

  As described above, in the hot water supply apparatus 10 of the present embodiment, when the connection state of the boiling forward pipe 31 and the boiling return pipe 32 and the inlet pipe 36 and the outlet pipe 37 is confirmed, the control unit is a heat pump unit ( The heating unit 13 and the boiling circulation pump 33 are operated. Then, the heat storage switching valve (flow rate adjusting means) 26 is controlled so that the heat storage fluid that has passed through the boiling return pipe 32 flows into the extraction pipe 41. Accordingly, the heat storage fluid boiled up by the heat pump unit 13 flows through the extraction pipe 41 if the connection state is normal. The temperature of the heat storage fluid that passes through the extraction pipe 41 is detected by a bath primary thermistor (temperature detection means) 45. Therefore, if the temperature detected by the bath primary thermistor 45 is lower than a predetermined temperature (for example, boiling temperature −15 ° C .: 50 ° C. if the heating temperature is 65 ° C.), the control section 31 and the boiling forward piping 31 and boiling It is determined that the upward return pipe 32, the inlet pipe 36, and the outlet pipe 37 are in a reverse connection state (steps S14 and S18). If the connection state is normal, since the heat storage fluid heated as described above passes, the detected temperature should not be lower than the predetermined temperature. If this is lower than the predetermined temperature, the boiled heat storage fluid has not passed through the extraction pipe 41. Therefore, the control unit can determine that the connection is reverse when the temperature is lower than the predetermined temperature. Moreover, since the heat storage fluid heated will flow into the extraction piping 41 if it is normal, if the control part implements the control for confirmation, it can determine in a short time whether it is reverse connection.

  Moreover, although a control part determines with it being reverse connection by the temperature which the bath primary thermistor 45 detected, this bath primary thermistor 45 is not provided in order to determine reverse connection. The bath primary thermistor 45 is provided to control the heat load circuit 14. Therefore, the bath primary thermistor 45 for controlling the heat load circuit 14 is originally used to determine reverse connection. Accordingly, it is possible to realize the hot water supply apparatus 10 that can determine reverse connection in a short time without using a dedicated sensor for determining reverse connection.

  In other words, before the water supply of the heat pump unit 13 is stored in the hot water storage tank 11, it passes through the bath heat exchanger 42 side for external heating use. Thereby, it is possible to confirm whether or not the connection of the piping of the heat pump unit 13 is reversed based on the detected temperature of the bath primary thermistor 45 on the intake piping 43 of the bath heat exchanger 42. Thus, the reverse connection can be reliably detected in a short time without newly requiring a functional component for the reverse connection.

  Moreover, in this embodiment, the heat | energy storage from the heat pump unit 13 can be changed into the path | route which goes to the bath heat exchanger 42 by operation, such as an operation switch. In other words, when an operation for confirming the connection state is performed by the operation switch (operation unit) (step S11), the control unit performs control for confirming the connection state (FIG. 3). Thereby, the connection state can be confirmed not only when the heat pump unit 13 is constructed but also at a timing desired by the user. For example, even when the pipe is once removed and reconnected due to a failure of the heat pump unit 13, the connection state can be confirmed. In such a case, the hot water storage tank 11 may store heat to some extent. However, in this embodiment, reverse connection is determined by the temperature detected by the bath primary thermistor 45 regardless of the heat storage state of the hot water storage tank 11. Therefore, since the connection state can be confirmed not only at the time of construction, convenience can be improved.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. 4 and 5. In the present embodiment, the piping configuration of the hot water supply apparatus 10A and the connection timing determination timing are different from those in the first embodiment.

  As shown in FIG. 4, the return piping 32 for boiling is provided with a path switching valve 90 instead of the bypass valve 34. To the path switching valve 90, a bypass pipe 35A, an auxiliary extraction pipe 410, a boiling return pipe 32, and an extraction pipe 41 are connected. The bypass pipe 35 </ b> A is not connected to the upper part of the hot water storage tank unit 20, but is connected to the boiling forward pipe 31. The bypass pipe 35A may be connected to the lower part of the hot water storage tank unit 20 (not shown). The auxiliary extraction pipe 410 connects the upper part of the hot water storage tank 11 and the path switching valve 90. The path switching valve 90 passes from the return pipe 32 for boiling through the auxiliary take-off pipe 410 to the upper part of the hot water storage tank 11 and passes through the bypass pipe 35A from the return pipe 32 for boiling to the forward pipe for boiling. The flow rate ratio with the flow rate (including the flow rate 0) flowing through 31 is adjusted. The take-out pipe 41 is connected to the upstream side of the path switching valve 90 of the boiling return pipe 32.

  Next, determination of whether or not the reverse connection state is established will be described with reference to FIG. The flowchart shown in FIG. 5 is performed in the power-on state of water heater 10A.

  In step S21, it is determined whether or not the amount of heat in the hot water storage tank 11 is equal to or less than the predetermined heat storage amount. If the amount of heat is equal to or less than the predetermined heat storage amount, the process proceeds to step S22. repeat. The amount of heat stored in the hot water storage tank 11 is calculated based on the temperatures detected by the water temperature thermistors (Th1 to Th6, Tthp) arranged in the height direction of the hot water storage tank 11. The predetermined heat storage amount of the hot water storage tank 11 is set to a value where there is almost no heat storage amount in the hot water storage tank 11. In such a case, there is a high possibility of being in an initial installation state such as during construction, so it is confirmed whether or not the connection state is normal. Further, as shown in the flowchart of FIG.

  In step S22, the path switching valve 90 and the bath primary pump 44 are controlled, and the process proceeds to step S23. Specifically, the path switching valve 90 is controlled so that the boiling from the heat pump unit 13 passes from the return pipe 32 for boiling through the auxiliary extraction pipe 410 toward the upper part of the hot water storage tank 11. Further, the bath primary pump 44 is operated so that the heat storage fluid passes through the boiling return pipe 32 and goes to the extraction pipe 41. In this case, if the bath primary pump is not operated, the heat storage fluid does not flow into the extraction pipe 41 due to the pressure loss of the bath check valve 46 and the bath heat exchanger 42.

  In step S23, the heat pump unit 13 is operated to drive the boiling circulation pump 33, and the process proceeds to step S24. As a result, the heat storage fluid in the hot water storage tank 11 is heated. The heated heat storage fluid flows into the extraction pipe 41. The heat storage fluid that has flowed through the extraction pipe 41 passes through the bath heat exchanger 42, flows through the intake pipe 43, and is supplied to the hot water storage tank 11. In step S24, it is determined whether or not the detected temperature of the bath primary thermistor 45 provided in the intake pipe 43 is 50 degrees or more. If it is 50 degrees or more, the process proceeds to step S25. The process proceeds to step S28. As described above, the heat storage fluid boiled up by the operation of the heat pump unit 13 passes through the intake pipe 43. Therefore, if the connection state of the pipe is normal, the boiled heat storage fluid is supplied to the intake pipe. 43 is passed. Therefore, the bath primary thermistor 45 detects the temperature of the boiled heat storage fluid.

  In step S25, since it is 50 degrees or more, it is determined that it is normally connected, the bath primary pump 44 is stopped, and the process proceeds to step S26.

  In step S26, the heat pump unit 13 performs boiling control for storing hot water in the hot water storage tank 11, and the process proceeds to step S27. In step S27, it is determined whether or not the hot water storage tank 11 is filled with boiled hot water. If boiling is completed, the process proceeds to step S210, and the control in step S26 is repeated until boiling is completed.

  In step S28, since the detected temperature of the bath primary thermistor 45 is not 50 ° C. or more, it is determined whether or not a predetermined determination condition is satisfied. If the determination condition is satisfied, the process proceeds to step S29, and the determination condition is set. If not, the process returns to step S24. The determination conditions are the same as those in the first embodiment.

  In step S29, since the determination condition is satisfied, it is determined that the reverse connection state is established, the user is notified of the reverse connection, and the process proceeds to step S210. As a result, the user can recognize that the user is in the reverse connection state.

  In step S210, since it has been notified that boiling has been completed or reverse connection, the operation of the heat pump unit 13 is terminated, and the process proceeds to step S211. In step S211, the path switching valve 90 is controlled so that the inflowing heat storage fluid flows from the path switching valve 90 toward the boiling forward piping 31, and this flow is finished.

  As described above, in the present embodiment, when the heat pump unit 13 is operated when the hot water storage tank 11 has a certain amount of heat or less, the heat storage fluid is controlled to flow to the bath heat exchanger 42. In other words, the control unit performs control for confirming the connection state when the heat storage amount detected by each water temperature thermistor (heat storage amount detection means) is equal to or less than a predetermined amount (step S21). As a result, when the heat storage amount is equal to or less than a predetermined amount, the connection state is automatically confirmed. Therefore, when the user has not been operated for a long period of time or left immediately after the construction, the connection state is automatically confirmed, so that convenience is improved. Also, when left unattended for a long time, the possibility that the connection state is changed from the normal state to the reverse connection state is extremely low. In this case, it is a confirmation whether the heat pump unit 13 operates normally rather than a confirmation of the connection state. For example, when the heat pump unit 13 does not operate normally, the heat storage fluid passes through the intake pipe 43 while the temperature is low. In such a case, the reverse connection is notified in the flowchart shown in FIG. Because.

(Other embodiments)
The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  The structure of the said embodiment is an illustration to the last, Comprising: The scope of the present invention is not limited to the range of these description. The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

  In the first embodiment described above, the heat storage fluid and the hot water supply fluid are the same, but are not limited to the same case, and the heat storage fluid and the hot water supply fluid may be different. That is, the heat storage fluid and the hot water supply fluid may be subjected to heat exchange to increase the temperature of the hot water supply fluid.

  Further, the heat exchanger of the heat load circuit 14 was a reheating of the bathtub water of the bathtub 51 as a heat load for exchanging heat with the hot water of the hot water storage tank 11, but is not limited to reheating, and hot water heating such as floor heating. You may apply when you do.

  In the first embodiment described above, the bath primary thermistor 45 detects the temperature of the heat storage fluid passing through the intake pipe 43, but is not limited to the temperature of the heat storage fluid passing through the intake pipe 43. Absent. The bath primary thermistor 45 may detect the temperature of the heat storage fluid passing through the extraction pipe 41 on the downstream side of the heat storage switching valve 26, or may detect the temperature of the heat storage fluid flowing through the first flow part 42a. Good. In other words, the bath primary thermistor 45 may detect the temperature of the heat storage fluid after passing through the heat storage switching valve 26 and passing through the intake pipe 43 and flowing into the hot water storage tank 11. 3 may be connected to the lower part of the hot water storage tank 11.

10 ... Hot water supply device 11 ... Hot water storage tank (tank)
DESCRIPTION OF SYMBOLS 11b ... Water temperature thermistor (heat storage amount detection means) 12 ... Boiling circuit 13 ... Heat pump unit (heating part) 14 ... Heat load circuit 26 ... Heat storage switching valve (flow rate control means) 31 ... Boiling forward piping (pipe)
32 ... Return piping for boiling (pipe) 33 ... Circulating pump for boiling 36 ... Inlet piping 37 ... Outlet piping 41 ... Extraction piping 42 ... Bath heat exchanger (heat exchanger)
43 ... Intake piping 44 ... Bath primary pump (circulation pump for heat load)
45 ... Bath primary thermistor (temperature detection means) 80 ... Bath water circulation circuit 90 ... Path switching valve (flow rate adjustment means)

Claims (3)

A tank (11) for storing heat storage fluid therein;
A heating section (13) for heating the heat storage fluid flowing from the inlet pipe and discharging it to the outlet pipe;
A boiling forward pipe (31) for connecting the lower part of the tank and the inlet pipe of the heating part, a return pipe for boiling (32) for connecting the outlet pipe of the heating part and the upper part of the tank, And a boiling circulation pump (33) for circulating the heat storage fluid at the lower part of the tank in a direction to return from the boiling forward pipe to the upper part of the tank via the heating unit and the boiling return pipe A boiling circuit (12) having:
An extraction pipe (41) connected to the return pipe for boiling, a heat exchanger (42) for exchanging heat with the heat storage fluid that has passed through the extraction pipe, and a heat storage fluid that has passed through the heat exchanger An intake pipe (43) for returning the tank to the tank, and a heat load circulation pump for circulating the heat storage fluid in the tank in a direction to return to the tank from the extraction pipe via the heat exchanger and the intake pipe (44) and a thermal load circuit (14) having temperature detection means (45) for detecting the temperature of the heat storage fluid passing through the extraction pipe;
Flow rate adjusting means (26, 90) for controlling the flow rate of the heat storage fluid that passes through the boiling return pipe and returns to the upper part of the tank;
A control unit for controlling the heating unit, the flow rate adjusting means, the boiling circulation pump and the heat load circulation pump;
The control unit operates the heating unit and the circulating pump for boiling, controls the flow rate adjusting means so that the heat storage fluid that has passed through the return piping for boiling flows into the extraction piping, and the temperature If the temperature detected by the detection means is lower than a predetermined boiling temperature, it is determined that the connection between the boiling forward pipe and the boiling return pipe and the inlet pipe and the outlet pipe is in a reverse connection state. Hot water supply device characterized by An operation unit for operating the heating unit, the flow rate adjusting unit, the boiling circulation pump, and the heat load circulation pump;
The hot water supply apparatus according to claim 1, wherein the control unit performs control for determining whether or not the reverse connection state is established when a predetermined operation is performed by the operation unit. . Including a heat storage amount detecting means for detecting a heat storage amount of the heat storage fluid in the tank,
The said control part implements control for determining whether it is in the said reverse connection state, when the thermal storage amount detected by the said thermal storage amount detection means is below a predetermined amount. Or the hot water supply apparatus of 2.

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