JP6458629B2 - Water heater - Google Patents

Description

  The present invention relates to a hot water supply apparatus that supplies hot water via a pipe connected to a hot water storage tank that stores hot water heated by a heating source.

  As such a hot water supply device, one described in Patent Document 1 below is known. The hot water supply device described in Patent Literature 1 below is connected to a hot water storage tank for storing hot water heated by the heating means, and the hot water in the hot water storage tank is connected to the upper part of the hot water storage tank when the pressure in the hot water storage tank exceeds a first set pressure. A first pressure relief valve that discharges, and a second pressure relief valve that is connected to the lower part of the hot water storage tank and discharges hot water or water in the hot water storage tank when the pressure in the hot water storage tank exceeds the second set pressure. The set pressure is set higher than the second set pressure.

JP 2010-243121 A

  Since the conventional hot water supply apparatus can drain the expanded water from the lower part of the hot water storage tank, the energy consumption efficiency is improved throughout the year. However, since air accumulated in the hot water storage tank cannot be discharged together with the expanded water from the upper tank, it is necessary to discharge air during normal hot water. If air is discharged during normal hot water in this way, the temperature of the hot water may be lowered and air discharge noise may be generated, which may impair user comfort.

  The present invention has been made in view of such problems, and its purpose is to avoid a decrease in the temperature of the hot water and the generation of air discharge noise as much as possible even when a relief valve is provided in the lower part of the hot water storage tank. It is in providing the hot-water supply apparatus which can do.

In order to solve the above problems, a hot water supply apparatus according to the present invention supplies hot water via a hot water supply pipe connected to a hot water storage tank (11) for storing hot water heated by a heating source (13). The hot water supply device (10), wherein the hot water from the upper part of the hot water storage tank and the low temperature water from the middle and lower part of the hot water storage tank are mixed and sent to the hot water use side terminal via the hot water supply pipe A mixing valve (30), a temperature detection unit (61, 73) for detecting the temperature of the hot water mixed by the intermediate hot water mixing valve, and an upper part of the hot water storage tank are provided in the hot water supply pipe from the intermediate hot water valve. A first relief valve (52) disposed on the upstream side, a second relief valve (90) provided at a lower portion of the hot water storage tank and having a set pressure lower than that of the first relief valve, and the intermediate temperature water mixing The valve opening, the temperature And a controller (100) that adjusts according to the detected temperature of the outlet, and after detecting the hot water from the hot water storage tank, the controller does not depend on the detected temperature of the temperature detector, the medium hot water Expanded water air that causes the opening of the mixing valve to adjust the amount of hot water flowing through the hot water supply pipe to be changed from the first opening to the second opening, and that the air accumulated in the upper part of the hot water storage tank is sent to the hot water use side terminal together with the hot water The removal control is executed.

  In the present invention, the expansion water bleed control for changing the opening degree of the intermediate temperature water mixing valve from the first opening degree to the second opening degree is performed regardless of the temperature detected by the temperature detecting unit. The opening degree of the intermediate hot water mixing valve can be adjusted to an opening degree at which air can be extracted optimally, and a decrease in the hot water temperature and the generation of air discharge noise can be avoided as much as possible.

  ADVANTAGE OF THE INVENTION According to this invention, even if it is a case where a relief valve is provided in the lower part of the hot water storage tank, the hot water supply apparatus which can avoid the fall of the hot water temperature and generation | occurrence | production of the air discharge | emission sound as much as possible can be provided.

It is a block diagram which shows schematic structure of the hot water supply apparatus which concerns on this embodiment. In the hot water supply apparatus shown in FIG. 1, it is a block diagram which shows the flow of the hot water for the case of discharging | emitting expansion water. In the hot-water supply apparatus shown by FIG. 1, it is a block diagram which shows the flow of the hot-water supply water in the case of discharging water from the shower of a bathroom. In the hot water supply apparatus shown in FIG. 1, it is a block diagram which shows the flow of the hot water for when hot water is discharged into a bath. FIG. 2 is a state transition diagram showing conditions in the case of performing expansion water air bleeding control in the hot water supply apparatus shown in FIG. 1. 2 is a flowchart in the case of performing expansion water bleeding control in the hot water supply apparatus shown in FIG. 1.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same constituent elements in the drawings will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.

  A hot water supply apparatus according to an embodiment of the present invention will be described with reference to FIGS. The hot water supply apparatus 10 according to the present embodiment is used for general households, and uses a heat storage fluid stored in the hot water storage tank 11 as a heat source, in addition to a hot water supply function to a kitchen, a washroom, a bathroom, etc. It has a function of chasing hot water to the bathtub 51 and hot-watered bathtub water. In the present embodiment, the same hot water supply water as the hot water supply side (heat load side) is used as the “heat storage fluid”.

  The hot water supply apparatus 10 includes a hot water storage tank unit 20, a heat pump unit 13, a control unit 100, and an operation unit 120 (a main remote controller 121 and a bathroom remote controller 122).

  The hot water storage tank unit 20 includes a hot water storage tank 11, a boiling circuit 12, a thermal load circuit 14, a water supply pipe 15, a hot water supply pipe 27, a bath pouring unit 70, and a bath water circulation circuit 80.

  The hot water storage tank 11 is a tank (container) that stores a heat storage fluid therein. The hot water storage tank 11 is made of a metal having excellent corrosion resistance, for example, stainless steel, and a heat insulating material is provided on the outer peripheral portion thereof. As a result, the hot water storage tank 11 can keep the heat storage fluid warm for a long time.

  The hot water storage tank 11 has a vertically long shape, and in order to detect the amount of hot water stored in the hot water storage tank 11 and the hot water storage temperature, seven first to seventh water temperature thermistors 111 to 117 arranged in the height direction are provided. . Each water temperature thermistor 111-117 is connected to the control part 100 mentioned later, and the temperature information of the heat storage fluid with which the hot water storage tank 11 was filled in each water level is output to the control part 100 mentioned later. Based on the temperature information output from each of the water temperature thermistors 111 to 117, the control unit 100 to be described later defines the boundary position between the hot water in the hot water storage tank 11 and the water before boiling in the hot water storage tank 11 and the hot water storage. The amount of hot water stored in the tank 11 can be detected.

  The hot water storage tank 11 is provided with an introduction port 11a on the bottom surface thereof. A city water inflow pipe 21 for supplying city water into the hot water storage tank 11 is connected to the introduction port 11a. The city water pipe 22 connected to the city water inflow pipe 21 is provided with a pressure reducing valve 23 that adjusts the water pressure of the introduced tap water to a predetermined pressure and prevents the back flow 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 city water inflow pipe 21 is provided with a second relief valve 90. The 2nd relief valve 90 is provided in the branch branch for discharge branched from between the connection part of the city water piping 22 and the piping 15 for water supply, and the inlet 11a. The second relief valve 90 discharges the heat storage fluid below the hot water storage tank 11 when the pressure in the hot water storage tank 11 rises to a second predetermined pressure or higher. Similarly, the relationship with the first relief valve 52 for discharging the heat storage fluid in the hot water storage tank 11 to the outside will be described later.

  Subsequently, the heat pump unit 13 is a “heating unit” that heats the heat storage fluid introduced from the inlet pipe 36 and derives it from the outlet pipe 37. Although not shown, the heat pump unit 13 of the present embodiment is connected so that at least a compressor, a water refrigerant heat exchanger as a radiator, a variable decompressor, an evaporator, and a gas-liquid separator constitute a closed circuit. Have a heat pump cycle. The heat pump cycle of this embodiment employs carbon dioxide as a refrigerant, and constitutes a vapor compression supercritical refrigeration cycle in which the high-pressure side refrigerant pressure exceeds the critical pressure of the refrigerant.

  The heat pump unit 13 is provided with an inflow side thermistor 13 a that detects the temperature of the heat storage fluid that flows into the heat pump unit 13 through the inlet pipe 36. The inflow side thermistor 13a detects temperature information used to adjust the heating capacity of the heat storage fluid by the heat pump unit 13, and is connected to the control unit 100 described later. The control unit 100 described later adjusts the heating capability of the heat pump unit 13 by controlling the operation of the variable pressure reducer and the compressor using the detection information (temperature information) of the inflow side thermistor 13a.

  The heat pump unit 13 stores heat by exchanging heat between a high-temperature and high-pressure refrigerant flowing through the refrigerant flow path of the water refrigerant heat exchanger and a heat storage fluid (water) flowing through the water flow path of the water refrigerant heat exchanger. It is possible to boil up the working fluid.

  Further, when the heat pump cycle is constituted by a supercritical refrigeration cycle as in the present embodiment, the heat storage fluid has a higher temperature than the general heat pump cycle (subcritical refrigeration cycle) (for example, about 85 ° C. to 90 ° C.). Can be boiled. The heat pump cycle mainly boiles hot water in the hot water storage tank 11 when the hot water storage capacity of the hot water storage tank 11 is insufficient or by using midnight power in the midnight time zone where the price setting is inexpensive. The heat pump unit 13 may employ, for example, an ejector refrigeration cycle using an electric ejector as a heat pump cycle, or a subcritical refrigeration cycle using an HFC refrigerant, an HFO refrigerant, or the like as a refrigerant. Good.

  Subsequently, 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 and 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 includes a boiling forward pipe 31 that connects the lower part of the hot water storage tank 11 and the inlet pipe 36, and a boiling return pipe 32 that connects the outlet pipe 37 and the upper part of the hot water storage tank 11.

  In addition, the boiling circuit 12 supplies the heat storage fluid in the lower part of the hot water storage tank 11 to the heating forward pipe 31, the inlet pipe 36, the heat pump unit 13, the outlet pipe 37, the boiling return pipe 32, and the upper part of the hot water storage tank 11. A boiling circulation pump 33 for flowing in this order. The boiling circulation pump 33 of the present embodiment is disposed in the inlet pipe 36 and is configured by a pump that flows in one direction to the inlet pipe 36, the heat pump unit 13, and the outlet pipe 37 in order.

  A bypass pipe 35 communicating with the boiling forward pipe 31 is connected to the boiling return pipe 32 of the present embodiment. A flow path switching valve 34 is provided at the junction of the boiling return pipe 32 and the bypass pipe 35.

  The flow path switching valve 34 is a three-way valve that switches the flow path of the heat storage fluid flowing through the boiling return pipe 32 to a flow path toward the upper part of the hot water storage tank 11 and a flow path toward the bypass pipe 35. In addition, the flow path switching valve 34 of the present embodiment is configured to be able to adjust the flow rate ratio between the flow rate of the heat storage fluid flowing toward the upper part of the hot water storage tank 11 and the flow rate of the heat storage fluid flowing in the bypass pipe 35.

  Subsequently, the heat load circuit 14 is a circuit for performing heat exchange between the heat storage fluid in the hot water storage tank 11 and the bathtub water (hot water supply water) stored in the bathtub 51, and chasing the bathtub water in the bathtub 51. . The thermal load circuit 14 of the present embodiment 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 a pipe for taking out the heat storage fluid from the upper part of the hot water storage tank 11 through the boiling return pipe 32, and is connected to the upstream side of the flow path switching valve 34 in the boiling return pipe 32. The pipe 410 extending from the flow path switching valve 34 to the upper part of the hot water storage tank 11 in the return pipe 32 for boiling also functions as a pipe (auxiliary extraction pipe) for taking out the heat storage fluid from the upper part of the hot water storage tank 11 to the extraction pipe 41. To do.

  The extraction pipe 41 of the present embodiment is provided with a bath primary check valve 46. The bath primary check valve 46 is provided to prevent the heat storage fluid from flowing backward from the intake pipe 43 side to the extraction pipe 41 side via the bath heat exchanger 42. The bath primary check valve 46 also functions as a flow resistance that prevents the heat storage fluid in the return return pipe 32 from flowing into the extraction pipe 41 when the bath primary pump 44 is stopped.

  The bath heat exchanger 42 is a “heat load heat exchanger” that exchanges heat between the heat storage fluid that has passed through the extraction pipe 41 and bath water (hot water supply water) that is used on the bath side (heat load side). Specifically, the bath heat exchanger 42 includes a first circulation part 42a through which heat storage fluid circulates and a second circulation part 42b through which bathtub water circulates, and fluids flowing through the circulation parts 42a and 42b are connected to each other. It is configured to exchange heat.

  The intake pipe 43 is a pipe that returns the heat storage fluid that has passed through the bath heat exchanger 42 to the hot water storage tank 11. The intake pipe 43 is provided with a bath primary pump 44 and a bath primary thermistor 45 that detects the temperature of the heat storage fluid passing through the intake pipe 43.

  The bath primary pump 44 is a heat load circulation pump for flowing the heat storage fluid in the boiling return pipe 32 in the order of the extraction pipe 41, the bath heat exchanger 42, the intake pipe 43, and the hot water storage tank 11.

  The bath primary pump 44 has a heat storage fluid flowing through the heat pump unit 13 and an upper portion of the hot water storage tank 11 when the return piping 32 for boiling and the upper portion of the hot water storage tank 11 communicate with each other through the flow path switching valve 34. Each of the heat storage fluids is caused to flow to the extraction pipe 41 via the boiling return pipe 32.

  The bath primary pump 44 returns only the heat storage fluid flowing through the heat pump unit 13 when the return switching pipe 32 is not in communication with the upper part of the hot water storage tank 11 by the flow path switching valve 34. It flows to the extraction pipe 41 through the pipe 32.

  When the operation of the bath primary pump 44 is stopped, the bath primary check valve 46 becomes a flow resistance that prevents the heat storage fluid in the return piping 32 for boiling from flowing into the extraction piping 41 side. The heat storage fluid in the return pipe 32 hardly flows into the extraction pipe 41.

  As described above, in the present embodiment, the flow rate of the heat storage fluid that flows from the boiling return pipe 32 to the extraction pipe 41 is adjusted by the operation of the bath primary pump 44 and the setting of the flow path switching valve 34. Therefore, in this embodiment, the bath primary pump 44 and the flow path switching valve 34 constitute “flow rate adjusting means” that adjusts the flow rate of the heat storage fluid that flows from the return piping 32 for boiling to the extraction piping 41.

  The bath primary thermistor 45 detects temperature information used for adjusting the heat exchange capability of the bath heat exchanger 42 and is connected to the control unit 100 described later. The control unit 100 described later adjusts the heat exchange capability of the bath heat exchanger 42 by controlling the number of revolutions of the bath primary pump 44 using temperature information detected by the bath primary thermistor 45.

  Subsequently, the hot water supply pipe 27 is connected to the upper part of the hot water storage tank 11, and the heat storage fluid (high temperature water) at the upper part of the hot water storage tank 11 is used as the shower 54 in the bathroom provided on the most downstream side, the faucet in the kitchen and the washroom. It is a pipe for leading to the hot water usage side terminal.

  A discharge pipe 53 provided with a first relief valve 52 is connected to the hot water supply pipe 27 in the middle of the route to the hot water use side terminal. The first relief valve 52 discharges the heat storage fluid (high temperature water) in the upper part of the hot water storage tank 11 to the outside when the pressure in the hot water storage tank 11 rises to a first predetermined pressure or higher. The first predetermined pressure is configured to be higher than the second predetermined pressure of the second relief valve 90 described above.

  In addition, an intermediate hot water pipe 29 is connected downstream of the discharge pipe 53 in the hot water supply pipe 27. The intermediate hot water pipe 29 is a pipe for deriving a heat storage fluid (intermediate hot water) that is an intermediate temperature in the hot water storage tank 11 from an intermediate hot water portion that constitutes a middle stage 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. This intermediate temperature water mixing valve 30 is configured to be able to adjust the mixing ratio of the high temperature water taken out from the hot water supply pipe 27 and the intermediate temperature water taken out from the intermediate temperature water pipe 29, and by adjusting the mixing ratio of the high temperature water and the intermediate temperature water, It is a temperature adjustment valve that adjusts the temperature of the heat storage fluid flowing through the hot water supply pipe 27. The intermediate temperature water pipe 29 is provided with intermediate temperature water for preventing the heat storage fluid (high temperature water) in the upper part of the hot water storage tank 11 from flowing back to the intermediate temperature water section of the hot water storage tank 11 via the intermediate temperature water mixing valve 30. A check valve 17 is provided.

  On the downstream side of the hot / cold water mixing valve 30 in the hot water supply pipe 27, a bath pipe 28 that guides the heat storage fluid flowing in the hot water supply pipe 27 to the bathtub 51 through a bath outlet pipe 81 described later is connected. A water supply pipe 15 is connected to the bath pipe 28, and a bath mixing valve 24 is provided at a junction with the water supply pipe 15.

  The bath mixing valve 24 is configured to be capable of adjusting a flow rate ratio between the flow rate of hot water supplied by the intermediate temperature water mixing valve 30 and the flow rate of water introduced from the city water pipe 22. Thus, the temperature adjustment valve adjusts the temperature of the hot water supplied from the end of the bath pipe 28. The flow rate ratio in the bath mixing valve 24 is adjusted according to the detection value of the bath thermistor 73 provided on the outlet side of the bath mixing valve 24.

  A bath pouring unit 70 for pouring hot water into the bathtub 51 is provided on the downstream side of the bath mixing valve 24 in the bath piping 28. The bath pouring unit 70 detects the flow rate of hot water flowing in the bath piping 28, the bath solenoid valve 71 (open / close valve), the backflow prevention valve 72, the bath thermistor 73 that detects the temperature of hot water flowing in the bath piping 28. A bath flow counter 74 and two bath check valves 75 are provided.

  The bath solenoid valve 71 is opened when the bathtub 51 is filled with hot water, hot water or additional hot water. The bath solenoid valve 71 is controlled by the control unit 100 so that the mixed hot water of a predetermined flow rate is discharged based on the flow rate information detected by the bath flow rate counter 74. When the flow rate of water in the bath pipe 28 is detected by the bath flow rate counter 74, the bath electromagnetic valve 71 is opened and hot water supply water is being discharged.

  The two check valves 75 for bath are provided to prevent backflow of bath water in the bath water circulation circuit 80 described later to the bath mixing valve 24 side. 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 operates the backflow prevention valve 72 according to the pressure difference between the two connection points when there is bathtub water to enter the hot water supply pipe 27 side, and the bathtub water is supplied to the outside of the bath pouring unit 70. Can be discharged.

  A water supply pipe 15 is connected to a downstream side of the hot water supply pipe 27 with respect to the connection with the bath pipe 28, and a hot water supply mixing valve 25 is provided at a junction with the water supply pipe 15. The hot water supply mixing valve 25 is configured to be able to adjust the flow rate ratio between the flow rate of hot water supplied by the hot water mixing valve 30 and the flow rate of water introduced from the city water pipe 22. Thus, the temperature adjustment valve adjusts the temperature of the hot water to be discharged at the end of the hot water supply pipe 27. The flow rate ratio in the hot water supply mixing valve 25 is adjusted according to the detection value of the hot water supply thermistor 61 (temperature detection unit) provided on the outlet side of the hot water supply mixing valve 25.

  On the downstream side of the hot water supply mixing valve 25 in the hot water supply pipe 27, a hot water supply thermistor 61 that detects the temperature of hot water flowing through the hot water supply pipe 27, a hot water supply flow rate counter 62 that detects the flow rate of hot water flowing through the hot water supply pipe 27, and hot water supply A check valve 63 is provided.

  The hot water check valve 63 is provided to prevent the backflow of the heat storage fluid from the shower 54 at the end of the hot water supply pipe 27 to the hot water supply mixing valve 25 side. When the flow of water in the hot water supply pipe 27 is detected by the hot water supply flow rate counter 62, the hot water supply water is being discharged from the shower 54 or the like at the end of the hot water supply pipe 27.

  Next, the bath water circulation circuit 80 will be described. The bath water circulation circuit 80 is a circuit for circulating the bathtub water stored in the bathtub 51 to the bath heat exchanger 42 to track the bathtub water in the bathtub 51. In the present embodiment, the bath pouring unit 70 and the bath water circulation circuit 80 constitute a “bathtub circuit”.

  The bath water circulation circuit 80 of the present embodiment has 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 the bath water heat-exchanged in the bath heat exchanger 42 in the bathtub 51. A bath return pipe 82 is provided.

  In the bath-out piping 81, a water level sensor 87, a bath circulation sensor 83 that detects whether or not the bath water is flowing to the bath heat exchanger 42 side, and a bath that detects the bath water temperature of the bath 51 in order from the bath 51 side. A reheating thermistor 85 and a bath circulation pump 84 are provided. The bath return pipe 82 is provided with a bath heat exchange thermistor 86 that detects the outlet temperature of the bath heat exchanger 42.

  The bath circulation pump 84 is a pump that flows the bathtub water in the bathtub 51 in the order of the bath outlet pipe 81, the bath heat exchanger 42, the bath return pipe 82, and the bathtub 51 when chasing the bathtub water in the bathtub 51. .

  The water level sensor 87 is water level detection means for detecting the water level in the bathtub 51. Since the water pressure (static pressure) in the bath outlet pipe 81 increases as the water level in the bathtub 51 rises, in this embodiment, a pressure sensor that detects the water pressure in the bath outlet pipe 81 is adopted as the water level sensor 87. doing.

  Here, the downstream end of the bath pipe 28 is connected between the bath circulation pump 84 and the bath heat exchanger 42. Accordingly, when the bath solenoid valve 71 is opened during the hot water filling operation of the bathtub 51, hot water supply water adjusted to a desired temperature by the bath mixing valve 24 is supplied from the bath outlet pipe 81 to the bathtub 51. At the same time, the water is supplied from the bath outlet pipe 81 to the bathtub 51 through the bath heat exchanger 42 and the bath return pipe 82.

  Then, the control part 100 which is an electronic control part of the hot water supply apparatus of this embodiment is demonstrated. The control unit 100 is configured mainly with a microcomputer, and preset control programs and updatable control programs are stored in various memories (ROM, RAM, EEPROM, etc.) built in as storage means.

  On the input side of the control unit 100, there is a sensor group for hot water supply such as each thermistor 111 to 117, 13a, 45, 61, 73, 85, 86, each flow counter 62, 74, bath circulation sensor 83, water level sensor 87, and the like. It is connected. In addition, a main remote controller 121, a bathroom remote controller 122, and the like, which will be described later, are connected to the control unit 100 so as to be capable of bidirectional communication.

  Various control devices such as the heat pump unit 13, the mixing valves 24, 25, 30, the bath electromagnetic valve 71, the flow path switching valve 34, and the circulation pumps 33, 44, 84 are connected to the output side of the control unit 100. ing. The control unit 100 controls various control devices based on detection information of the hot water supply sensor group, operation signals from the remote controllers 121 and 122, and the like.

  Next, the main remote controller 121 and the bathroom remote controller 122 will be described. Each of the remote controllers 121 and 122 is an operation unit 120 for the user to request the control unit 100 to perform various operations such as a boiling operation, a cooking operation, and a hot water operation.

  The main remote controller 121 is an operation unit 120 that is installed in a place (kitchen or the like) other than the bathroom to operate the entire hot water supply device. On the other hand, the bathroom remote controller 122 is an operation unit 120 that is installed in a bathroom and mainly operates a bath function.

  Then, operation | movement of the hot water supply apparatus 10 is demonstrated. In the present embodiment, a typical operation after the installation of the hot water supply apparatus 10 is completed (after the trial operation is performed) will be described.

  First, the boiling operation of the heat storage fluid in the hot water storage tank 11 after the installation of the hot water supply device 10 is completed will be described. This boiling operation is performed by the control unit 100 in a specific boiling time zone (for example, a night time zone of a lighting system according to time zone).

  During the boiling operation, the control unit 100 controls the flow path switching valve 34 so that the flow path of the heat storage fluid flowing through the boiling return pipe 32 becomes a flow path toward the upper part of the hot water storage tank 11. Thereafter, the control unit 100 operates the heat pump unit 13 and the boiling circulation pump 33 so that the preset amount of hot water or the total amount of hot water in the hot water storage tank 11 is stored on the upper side of the hot water storage tank 11.

  Thereby, the heat storage fluid in the lower part of the hot water storage tank 11 flows in the order of the boiling forward pipe 31, the inlet pipe 36, the heat pump unit 13, the outlet pipe 37, the boiling return pipe 32, and the upper part of the hot water storage tank 11. Then, the heat storage fluid in the lower part of the hot water storage tank 11 is boiled up to a predetermined boiling temperature when passing through the heat pump unit 13, and is stored in the upper part of the hot water storage tank 11.

  When the temperature of the heat storage fluid in the hot water storage tank 11 rises and the internal pressure of the hot water storage tank 11 becomes equal to or higher than the second predetermined pressure, the second relief valve 90 opens and discharges the expanded water (see FIG. 2).

  Next, a hot water supply operation using the heat storage fluid in the hot water storage tank 11 after the installation of the hot water supply apparatus 10 is completed will be described. This hot water supply operation is executed when the control unit 100 receives a request signal for requesting execution of the hot water supply operation from each of the remote controllers 121 and 122, for example.

  During the hot water supply operation, the user opens a hot water tap or the like disposed at the end of the hot water supply pipe 27. The heat storage fluid in the hot water storage tank 11 is pushed out to the hot water supply pipe 27 side by the water supply pressure at this time, and the heat storage fluid from the hot water storage tank 11 and the water from the city water inflow pipe 21 are connected to each mixing valve 25 through each pipe. , 30 and adjusted to a desired temperature (hot water supply set temperature). Thereafter, the hot water for which the temperature is adjusted by the mixing valves 25 and 30 is supplied to the shower 54 at the end of the hot water supply pipe 27 (see FIG. 3).

  Next, the hot water filling operation of the bathtub 51 after the installation of the hot water supply apparatus 10 is completed will be described. This hot water filling operation is executed when the control unit 100 receives a request signal for requesting execution of the hot water filling operation from each of the remote controllers 121 and 122, for example.

  During the hot water operation, the control unit 100 opens the bath solenoid valve 71. The heat storage fluid in the hot water storage tank 11 is pushed out to the bath pipe 28 side by the supply water pressure at this time, and the heat storage fluid from the hot water storage tank 11 and the water from the city water inflow pipe 21 are mixed by the mixing valves 24 and 30. Then, the temperature is adjusted to a desired temperature (a hot water filling set temperature). After that, the hot water supply water whose temperature is adjusted by the mixing valves 24 and 30 is supplied to the bathtub 51 through the bath water circulation circuit 80 (see FIG. 4).

  After that, when the hot water filling is completed by supplying the hot water supply of the target hot water amount to the bathtub 51, the control unit 100 closes the bath electromagnetic valve 71. And the control part 100 operates the bath circulation pump 84 every predetermined time, circulates the bath water of the bathtub 51 in the bath water circulation circuit 80, detects the temperature of bath water with the bath reheating thermistor 85, and heat-retains. It is necessary to monitor whether there is a need for reworking.

  The control unit 100 automatically performs a chasing operation when the temperature of the bath water is lower than the set temperature. In addition, the control part 100 performs a memorial operation also when the request signal which requests | requires execution of the extra cooking operation from each remote control 121,122 is received.

  At the time of the memorial operation, the control unit 100 first operates the bath circulation pump 84 to take the bath water into the bath water circulation circuit 80 and circulate it to the bath heat exchanger 42. In this state, the control unit 100 controls the flow path switching valve 34 so that the boiling return pipe 32 and the upper part of the hot water storage tank 11 communicate with each other, and operates the bath primary pump 44.

  Thereby, the heat storage fluid directly supplied from the heat pump unit 13 and the heat storage fluid in the hot water storage tank 11 flow to the bath heat exchanger 42 through the extraction pipe 41. At this time, in the bath heat exchanger 42, the heat storage fluid and the bathtub water from the bathtub 51 exchange heat, and the temperature of the bathtub water rises. Note that the heat storage fluid that has passed through the bath heat exchanger 42 and has a temperature drop returns to the hot water storage tank 11 through the intake pipe 43.

  Further, the control unit 100 detects the temperature of the bath water that has passed through the bath heat exchanger 42 with the bath heat exchanger thermistor 86 and the temperature of the heat storage fluid that has passed through the bath heat exchanger 42 with the bath primary thermistor 45. To detect. Then, based on the detected temperatures detected by the thermistors 45 and 86, the bath primary pump 44 is set so that the temperature of the bath water that has passed through the bath heat exchanger 42 becomes a target temperature determined according to the set temperature. The number of rotations is controlled, and the temperature of the bathtub water in the bathtub 51 is raised to the set temperature.

  In the hot water supply apparatus 10 according to the present embodiment, the relationship between the expanded water air bleeding control and the temperature adjustment control will be described with reference to the state transition diagram shown in FIG. If any of the conditions of the abnormal reset operation when an abnormality occurs is satisfied for 10 seconds or more after power-on (microcomputer reset) and recovery from a power failure, the medium temperature water temperature control mode 0_ST1 is entered. In the medium temperature water temperature control mode 0_ST1, the origin control of the medium temperature water mixing valve 30 is executed.

  When the origin control in the medium temperature water temperature control mode 0_ST1 is completed, a transition is made to the medium temperature water temperature control mode 1_ST2. In the intermediate temperature water temperature control mode 1_ST2, the hot water stop control is performed so that the intermediate temperature water mixing valve 30 is closed.

  In the intermediate temperature water temperature control mode 1_ST2, when a predetermined time elapses from the hot water stop control in which the intermediate temperature water mixing valve 30 is closed, and an operation request for hot water filling, additional hot water, or reheating is entered, the intermediate temperature Transition to water temperature control mode 2_ST3. In the medium temperature water temperature control mode 2_ST3, FF control (feed forward control) is executed.

  In the middle temperature water temperature control mode 1_ST2, when a predetermined time elapses from the hot water stop control in which the middle temperature water mixing valve 30 is closed and an operation request for draining operation from the bathtub 51 is entered, the middle temperature water temperature control mode 4_ST4. Transition to. In the medium temperature water temperature control mode 4_ST4, the opening degree fixing control is executed.

  When the FF control holding condition is satisfied in the medium temperature water temperature control mode 2_ST3, the state transitions to the medium temperature water temperature control mode 3_ST5. In the medium temperature water temperature control mode 3_ST5, FB control (feedback control) is executed. When the FF control transition condition is satisfied in the medium temperature water temperature control mode 3_ST5, the state transitions to the medium temperature water temperature control mode 2_ST3. When the hot water stop condition is satisfied in the medium temperature water temperature control mode 3_ST5, the state transitions to the medium temperature water temperature control mode 1_ST2.

  When the condition within 10 seconds from the recovery from the power failure is satisfied, the process shifts to the expanded water air bleeding control. The expanded water air bleed control has an expanded water bleed air standby ST6, a hot water supply air bleed control ST7, and a bath air bleed control ST8.

In the expansion water air bleeding standby ST6, the intermediate temperature water mixing valve 30 is maintained at an opening degree corresponding to the mixing ratio. The mixing ratio is obtained by the following equation.
Mixing ratio = (hot water set temperature−average feed water temperature) / (medium temperature water thermistor temperature−average feed water temperature) / 100
However, a specific example of the opening degree according to the mixing ratio of the intermediate temperature water mixing valve 30 is as follows: hot water supply set temperature> average supply water temperature and intermediate warm water thermistor temperature> average supply water temperature.
・ When the mixing ratio is less than 15%, the opening degree of the intermediate temperature water mixing valve 30 is 30 (A)%.
・ When the mixing ratio is 15% or more and less than 40%, the opening degree of the intermediate temperature water mixing valve 30 is 40 (B)%.
・ When the mixing ratio is 40% or more, the opening degree of the intermediate temperature water mixing valve 30 is 30 (C)%.

  In the hot water supply air bleeding control ST7, the minimum opening degree of the intermediate temperature water mixing valve 30 is maintained after a predetermined pulse has elapsed. In the bath air venting control ST8, the intermediate hot water mixing valve 30 is maintained at a predetermined opening (60 (D)%).

  In addition, the opening degree of the above-described intermediate temperature water mixing valve 30 is an example, and an opening degree that satisfies the relationship of A ≦ C ≦ B ≦ D is appropriately selected.

In the medium temperature water temperature control mode 1_ST2, when all the following conditions are satisfied, the process proceeds to the standby water bleeding standby ST6.
-The difference between the detected temperature of the thermistor 111 and the detected temperature of the thermistor 113 is less than 5 ° C.
-The detected temperature of the thermistor 113 is the medium hot water target temperature + 5 ° C or higher.
・ The heat pump unit 13 is boiling.

When one of the following conditions is satisfied in the expanded water air bleeding standby ST6, the process transits to the medium temperature water temperature control mode 1_ST2.
The difference between the detected temperature of the thermistor 111 and the detected temperature of the thermistor 113 is 8 ° C. or more.
-The temperature detected by the thermistor 113 is less than the target temperature of medium hot water + 2 ° C.
The sum of the accumulated hot water flow rate and the accumulated bath flow rate after completion of the heating of the heat pump unit 13 is equal to or greater than a predetermined value (the predetermined value is a threshold at which air accumulated in the hot water storage tank 11 is released after the heating of the heat pump unit 13 is completed).

  If the instantaneous value of the hot water supply flow rate is not 0 pps in the expansion water air bleeding standby ST6, the process proceeds to the hot water supply air bleeding control ST7. When an instruction to open the solenoid valve 71 for bath by automatic bathing is given in the standby water venting standby ST6, the process proceeds to bath air venting control ST8.

  If the instantaneous value of the hot water supply flow rate is not 0 pps in the bath air vent control ST8, the process proceeds to the hot water supply air vent control ST7. In the bath air vent control ST8, when the hot water supply flow rate and the bath flow rate remain at 0 pps for a predetermined time, the process proceeds to the expansion water air vent standby ST6. In the bath air venting control ST8, when the bath flow integrated value becomes equal to or greater than a predetermined pulse (a pulse for ensuring a sufficient amount of outflow water for air to escape), the mode transitions to the medium temperature water temperature control mode 3_ST5.

  In the hot water supply air bleeding control ST7, when the hot water flow rate and the bath flow rate remain at 0 pps for a predetermined time, the process proceeds to the expansion water air bleeding standby ST6. In the hot water supply air vent control ST7, when the hot water supply flow rate is kept at 0 pps for a predetermined time and an instruction to open the bath electromagnetic valve 71 by automatic bath is issued, the flow shifts to the bath air vent control ST8. In the hot water supply air bleed control ST7, when the hot water supply air bleed control completion flag is turned ON, a transition is made to the medium temperature water temperature control mode 3_ST5. After transitioning to the medium temperature water temperature control mode 3_ST5, the hot water supply air bleeding control completion flag is turned OFF. (The initial value of the hot water bleeding control completion flag is OFF)

  Next, a specific flow of hot water supply air bleeding control ST7 will be described with reference to FIG. In step S101, it is determined whether the instantaneous value of the hot water supply flow rate exceeds 0 pps. If the instantaneous hot water flow rate value does not exceed 0 pps, the determination in step S101 is repeated. If the instantaneous hot water flow rate value exceeds 0 pps, the process proceeds to step S102.

  In step S102, the hot water flow rate integrated value is set to zero. In step S103 following step S102, it is determined whether or not the mixing ratio of the intermediate temperature water mixing valve 30 is 40% or more. If the mixing ratio of the medium temperature water mixing valve 30 is 40% or more, the process proceeds to step S104. If the mixing ratio of the medium temperature water mixing valve 30 is not 40% or more, the process proceeds to step S108.

  In step S104, the opening degree of the intermediate temperature water mixing valve 30 is set to C%. In step S105 following step S104, it is determined whether or not the hot water supply flow rate integrated value has become c pulses or more. If the hot water supply flow rate integrated value is not greater than or equal to c pulses, the determination in step S105 is repeated. If the hot water flow rate integrated value is greater than or equal to c pulses, the process proceeds to step S106. In addition, “c pulse” means that when the opening degree of the intermediate temperature water mixing valve 30 is set to C%, a large amount of air escapes in a transient state immediately after the start of pouring, so that the temperature of the tapping water decreases and the sound of air discharge is reduced. This is the number of pulses corresponding to the flow rate considering generation as a minimum.

  In step S106, the opening degree of the intermediate temperature water mixing valve 30 is set to 25%. When the process of step S106 ends, the process proceeds to step 107. In step S107, it is determined whether or not the hot water supply flow rate integrated value has exceeded a predetermined pulse α. If it exceeds the predetermined pulse α, a hot water supply air bleeding control completion flag is turned on in step S116, and the process is terminated. The predetermined pulse α is the number of pulses for securing a sufficient amount of outflow water for air to escape.

  In step S108, it is determined whether or not the mixing ratio of the intermediate temperature water mixing valve 30 is 15% or more and less than 40%. If it is 15% or more and less than 40%, the process proceeds to step S109, and 15% or more and If it is not less than 40%, the process proceeds to step S112.

  In step S109, the opening degree of the intermediate temperature water mixing valve 30 is set to B%. In step S110 following step S109, it is determined whether or not the hot water supply flow rate integrated value is equal to or greater than b pulses. If the hot water supply flow rate integrated value is not greater than or equal to b pulses, the determination in step S110 is repeated. If the hot water flow rate integrated value is greater than or equal to b pulses, the process proceeds to step S111. Note that “b pulse” means that when the opening degree of the intermediate temperature water mixing valve 30 is set to B%, a large amount of air is released in a transient state immediately after the start of the hot water, so that the temperature of the hot water is lowered or the sound of the air discharged is reduced. This is the number of pulses corresponding to the flow rate considering generation as a minimum.

  In step S111, the opening degree of the intermediate temperature water mixing valve 30 is set to 25%. When the process of step S111 ends, the process proceeds to step 107. In step S107, it is determined whether or not the hot water supply flow rate integrated value has exceeded a predetermined pulse α. If it exceeds the predetermined pulse α, a hot water supply air bleeding control completion flag is turned on in step S116, and the process is terminated. The predetermined pulse α is the number of pulses for securing a sufficient amount of outflow water for air to escape.

  In step S112, the opening degree of the intermediate temperature water mixing valve 30 is set to A%. In step S113 following step S112, it is determined whether or not the hot water supply flow rate integrated value has become a pulse or more. If the hot water supply flow rate integrated value is not a pulse or more, the determination in step S113 is repeated, and if the hot water flow rate integrated value is a pulse or more, the process proceeds to step S114. In addition, “a pulse” means that when the opening degree of the intermediate temperature water mixing valve 30 is set to A%, a large amount of air is released in a transient state immediately after the start of the hot water, so that the temperature of the hot water is lowered and the sound of air discharge is reduced. This is the number of pulses corresponding to the flow rate considering generation as a minimum.

  In step S114, the opening degree of the intermediate temperature water mixing valve 30 is set to 25%. When the process of step S114 ends, the process proceeds to step 115. In step S115, it is determined whether or not the hot water supply flow rate integrated value has exceeded a predetermined pulse β. If it exceeds the predetermined pulse β, the hot water supply air bleeding control completion flag is turned on in step S116, and the process is terminated. The predetermined pulse β is the number of pulses for ensuring a sufficient amount of outflow water for air to escape. α ≦ β.

  In the above-described flow, although the opening degree of the intermediate temperature water mixing valve 30 is adjusted according to the mixing ratio of the intermediate temperature water mixing valve 30, the opening degree of the intermediate temperature water mixing valve 30 is adjusted instead using the flow rate as a factor. You can also Specifically, with respect to the hot water flow rate from the hot water storage tank 11, the hot water flow rate at the time of stabilization can be learned and stored, and the opening degree of the intermediate hot water mixing valve 30 can be adjusted based on the learned hot water flow rate at the time of stable storage. .

  In the case of reheating, it is also possible to open the bath solenoid valve 71 and evacuate the hot water tank 11 in the same way as when filling the hot water. Similarly, during the heat retention, the air in the hot water storage tank 11 can be extracted by opening the bath solenoid valve 71 in the same manner as when filling with hot water. After the bath electromagnetic valve 71 is opened and hot water having a flow rate necessary for extracting air is flowed, the bath electromagnetic valve 71 is closed to return to the chasing or heat retaining mode.

  When the water supply pressure is low, such as in mountainous areas or on the third floor, hot air may remain even if control is performed to release air in the hot water storage tank 11. Similarly, in this case, the air in the hot water storage tank 11 can be extracted by opening the bath electromagnetic valve 71 when chasing or keeping warm.

  In addition, it is also possible to execute the expansion water air bleeding control by supplying hot water to the bathtub 51 during or after the boiling by the heating source. In that case, after executing the expansion water air bleeding control, the automatic draining means (not shown) from the bathtub 51 can be operated to drain the water.

  Further, it is possible to perform the expansion water air bleeding control a plurality of times during boiling by the heating source, and to perform the expansion water air bleeding control only once after the boiling is completed. During boiling by the heating source, air accumulates in the hot water storage tank 11 in a few hours. Therefore, during the boiling, the air is extracted at an appropriate timing by executing the expansion water bleeding control multiple times. Can do. After the completion of boiling, if the air is once removed, the air will not accumulate after that, so that it is sufficient to execute the expansion water air bleeding control only once.

10: Hot water supply device 11: Hot water storage tank 111, 112, 113, 114, 115, 116, 117: Thermistor 13: Heat pump unit (heating source)
30: Medium hot water mixing valve 51: Bathtub 52: First relief valve 61: Hot water supply thermistor (temperature detection unit)
71: Solenoid valve for bath 73: Bath thermistor 84: Bath circulation pump 90: Second relief valve 100: Control unit 120: Operation unit

Claims (15)

In a hot water supply apparatus (10) configured to supply hot water via a hot water supply pipe connected to a hot water storage tank (11) for storing hot water heated by a heating source (13),
A hot water mixing valve (30) that mixes hot water from the upper part of the hot water storage tank and low temperature water from the middle and lower part of the hot water storage tank, and sends it out toward the hot water use side terminal via the hot water supply pipe ,
A temperature detector (61, 73) for detecting the temperature of the hot water mixed by the intermediate hot water mixing valve;
A first relief valve (52) provided at an upper portion of the hot water storage tank and disposed upstream of the intermediate hot water valve in the hot water supply pipe ;
A second relief valve (90) provided at a lower portion of the hot water storage tank and having a set pressure lower than that of the first relief valve;
A controller (100) that adjusts the opening of the intermediate temperature water mixing valve according to the detected temperature of the temperature detector;
After detecting the hot water from the hot water storage tank, the control unit adjusts the opening degree for adjusting the amount of hot water that the intermediate hot water mixing valve flows to the hot water supply pipe from the first opening degree, regardless of the temperature detected by the temperature detection unit. A hot water supply device that performs transition to the second opening degree and performs air expansion control for expanding water that sends out the air accumulated in the upper part of the hot water storage tank to the hot water supply use side terminal together with hot water.   The hot water supply device according to claim 1, wherein the first opening is larger than the second opening.   The controller sets the opening of the intermediate temperature water mixing valve to the first opening after detecting the hot water from the hot water storage tank, and after elapse of time necessary for the air in the hot water storage tank to escape The hot water supply apparatus according to claim 1, wherein the opening degree of the intermediate temperature water mixing valve is changed to the second opening degree.   3. The hot water supply apparatus according to claim 1, wherein the control unit executes the expansion water bleeding control only when a temperature difference between an upper portion and a middle bottom portion of the hot water storage tank is a predetermined temperature difference.   The said control part performs the said expansion | swelling water air bleeding control only when the sum total of the amount of outflow water from the said hot water storage tank is less than predetermined amount after the boiling by the said heat source is completed. 2. A hot water supply apparatus according to 2.   The said control part determines the said 1st opening degree based on the mixing ratio defined based on the hot-water supply preset temperature, feed water temperature, and the temperature which the said temperature detection part detects. The hot water supply device described in 1.   The controller supplies hot water to the bathtub (51) as a third opening larger than the first opening, and makes the transition to the second opening after a predetermined time, thereby expanding the expansion. The hot-water supply device according to claim 2, wherein water-bleeding control is executed.   The hot water supply apparatus according to claim 7, wherein the first opening, the second opening, and the third opening are changed stepwise or continuously.   The hot water flow rate from the hot water storage tank is learned and stored when the hot water flow rate is stable, and the first opening degree, the second opening degree, and the third opening degree are determined based on the learned hot water flow rate during the stable storage. The hot water supply device according to claim 7, wherein the hot water supply device is determined. The control unit executes the inflation water air bleeding control based on an instruction signal from the operation unit (120),
The hot water supply device according to claim 1 or 2, wherein execution or non-execution of the expanded water air bleeding control is determined based on an instruction signal from the operation unit.   The hot water supply apparatus according to claim 10, wherein the expansion water air bleeding control is immediately executed in response to an input of an instruction signal from the operation unit.   The hot water supply apparatus according to claim 1 or 2, wherein the control unit executes the expansion water air bleeding control in an initial stage of chasing or keeping warm.   3. The hot water supply according to claim 1, wherein the control unit performs the expansion water air bleeding control by supplying hot water to the bathtub (51) during or after the boiling by the heating source. 4. apparatus.   The hot water supply apparatus according to claim 13, wherein the control unit performs drainage by operating drainage means from the bathtub after execution of the expansion water bleeding control.   The said control part performs the said expansion water air bleeding control in multiple times during the boiling by the said heat source, and after the completion of boiling, performs the said expansion water air bleeding control only once. Item 3. A hot water supply apparatus according to item 1 or 2.

Images