JP2011002121A - Storage type water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a storage type water heater having an improved COP (Coefficient Of Performance) and high energy saving effects.SOLUTION: The storage type water heater includes: a hot water generating device for generating high temperature water by heating low temperature water; a hot water storage tank 132 for storing hot water; a reheating heat exchanger 150 for heating bath water; heat storage piping 146 connected to the hot water storage tank 132 from the hot water generating device; reheating piping 142 connected to the reheating heat exchanger 150 from the hot water generating device; and residual heat piping 144 for guiding residual heat water after heat exchange from the reheating heat exchanger 150 to the hot water storage tank 132. The residual heat piping 144 is connected to an intermediate temperature region which is a middle part in the height direction of the hot water storage tank 132.

Description

  The present invention relates to a hot water storage type hot water supply apparatus that stores hot water generated by heating water and supplies the stored hot water to a hot water supply facility.

  In recent years, hot water (hot water) is stored in a hot water tank (sometimes called a hot water tank) as one of the heat sources in houses, etc., and hot water is supplied from the hot water tank to hot water facilities as necessary. Widespread use of hot water heaters. Conventionally, heat was directly used by using energy such as electricity or gas as a heat source, but the temperature of heat used in a house or the like is not necessarily as high as several hundred degrees, for example, about 40 ° C. in a bath or shower, It is about 80-90 degreeC also in a water heater of a kitchen, and it is about 35-55 degreeC also in floor heating. Therefore, water can be sufficiently used as a heat medium, and by storing heat in this, it is possible to provide a time difference in receiving heat or to improve efficiency by collecting exhaust heat.

  As a hot water generator in such a hot water supply apparatus, a heat pump is widely used. In heat pumps, a heat medium (refrigerant) circulates inside, and by circulating the heat medium using electric power, water can be heated with a heat quantity that combines air heat and pump work. Hot water can be generated. In addition, since water can be used as a heat storage material, there is a time difference in receiving heat, so hot water generated using inexpensive nighttime electricity can be stored in a hot water storage tank and the stored hot water can be used during the day. (Customers) can reduce the cost of electricity.

  For example, Patent Document 1 discloses a hot water storage type water heater having a plurality of functions such as hot water heating and bath chase using a heat pump. According to the technique of Patent Document 1, it is said that a light-weight, compact and inexpensive hot water storage type hot water heater can be provided by arranging a plurality of heat exchangers in one circulation circuit using the same hot water as a heat source.

JP-A-2005-90908

  However, as mentioned above, even with hot water storage water heaters that can reduce costs by using inexpensive nighttime electricity, COP (Coefficient Of Performance) is improved to further improve the energy saving effect. It was necessary to let them. And in COP in the hot water production | generation apparatus of a hot water storage type hot water supply apparatus, it turns out that the value of COP is better to heat low temperature water to high temperature water than to heat medium temperature water to high temperature water.

  In the hot water storage type hot water supply apparatus of Patent Document 1, the hot water at the lower part of the hot water tank is heated by a heating means (hot water generator, etc.), but the heated hot water has passed through the heating heat exchanger and the bath heat exchanger. It is returned to the bottom again later. Even hot water whose temperature has decreased due to heat exchange does not fall below the temperature before bathing in the bath, so it is medium temperature water, or at least not low temperature water. Here, in view of the above-mentioned COP, increasing the temperature of the low-temperature water in the lower part of the hot water tank that is the target of heating by the hot water generator or the like is thought to lead to a decrease in COP.

  In view of such a problem, an object of the present invention is to provide a hot water storage type hot-water supply device with improved COP and high energy saving effect.

  In order to solve the above problems, a typical configuration of a hot water storage type hot water supply apparatus according to the present invention includes a hot water generation apparatus that generates high temperature water by heating low temperature water, a hot water storage tank that stores hot water, and a bath. From the follow-up heat exchanger that heats the bath water, the heat storage pipe connected from the hot water generator to the hot water tank, the follow-up pipe connected from the hot water generator to the follow-up heat exchanger, and the follow-up heat exchanger And a remaining heat pipe that guides the remaining heat water after heat exchange to the hot water storage tank, and the remaining heat pipe is connected to an intermediate temperature region that is a midway in the height direction of the hot water storage tank.

  According to the said structure, since the remaining heat water after heat exchange is returned to the intermediate temperature range of a hot water storage tank, the low temperature water which retains in the low temperature range heated by the hot water generator is not warmed. Therefore, it is possible to prevent a decrease in COP caused by an increase in the incoming water temperature of the hot water generator, thereby improving the COP. Therefore, it is possible to provide a hot water storage type hot water supply device having a high energy saving effect.

  When supplying high temperature water to the follow-up heat exchanger, the hot water generating device may generate high temperature water having a temperature higher than that when supplying high temperature water to the hot water storage tank.

  According to the above configuration, the temperature of the high-temperature water used as the heat source for the follow-up by the follow-up heat exchanger is further increased, so that the follow-up can be completed in a short time and the amount of water used can be suppressed. In addition, since the temperature of the remaining heat water flowing into the hot water storage tank becomes high, even if it is returned to the middle temperature range in the hot water storage tank, it does not flow into the low temperature range because its specific gravity is lighter than that of the low temperature water. Therefore, it is possible to further prevent a decrease in COP caused by an increase in the incoming water temperature of the hot water generator without warming the low temperature water in the hot water tank.

  The hot water storage type hot water supply device includes a water supply pipe for supplying water to the lower part of the hot water tank, a high temperature water extraction pipe for taking out high temperature water from the high temperature area at the top in the height direction of the hot water tank, and a medium temperature water from the middle temperature area. A hot water extraction pipe, a high temperature water extraction pipe, a medium temperature water extraction pipe, and a water supply pipe may be provided with high temperature water, medium temperature water, or a mixing pipe that mixes and supplies hot water.

  According to the above configuration, hot water and medium temperature water can be mixed and adjusted to hot water having a desired temperature, so that the medium temperature water in the hot water tank returned from the follow-up heat exchanger can be actively consumed. Since the hot water storage tank is newly supplied with water consumption (low temperature water) for the amount of consumption, the hot water generator can heat the cold water to generate high temperature water. From these things, it becomes possible to further improve the COP of the hot water storage type hot water supply apparatus.

  The hot water generator is preferably a heat pump. The heat pump uses a heat exchange cycle in which heat (energy) is acquired by heat transfer (heat conduction) between substances. For this reason, a hot water supply apparatus using such a heat pump can save energy and reduce carbon dioxide emissions as compared with a conventional hot water heater that burns fossil fuel or the like. Therefore, according to the said structure, the said hot-water production | generation apparatus can be used as the hot-water production | generation apparatus by which environmental load was reduced.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the hot water storage type hot-water supply apparatus with the high COP and the high energy-saving effect.

It is a figure explaining the structure of the hot water storage type hot-water supply apparatus concerning this embodiment. It is a figure explaining the apparatus structure of a comparative example. It is a Mollier diagram (TH diagram) of CO ₂ which is a heat medium of the heat pump unit.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

  In the following description, in the present embodiment, a heat pump type hot water supply apparatus provided with a heat pump as a hot water generation apparatus is exemplified as a hot water storage type hot water supply apparatus. However, the present invention is not limited thereto, and hot water is temporarily stored in a tank or the like. Any hot water storage device that supplies hot and cold water may be used.

  Drawing 1 is a figure explaining the composition of the hot water storage type hot-water supply device concerning this embodiment. In FIG. 1, a thick black solid line represents a pipe through which the heat medium circulates, and a white line represents a pipe through which water or hot water flows. As shown in FIG. 1A, a hot water storage type hot water supply apparatus (hereinafter referred to as a hot water supply apparatus 100) includes a heat pump unit 110 that is a hot water generation apparatus and a hot water storage unit 130.

  In the heat pump unit 110, carbon dioxide (hereinafter, referred to as a heat medium), which is a natural refrigerant, circulates in the heat pump unit 110, and heat or hot water is heated using the heat of the heat medium, and the hot water storage tank 132 and the follow-up described later are heated. Produces hot water to be supplied to the heat exchanger. In addition, when the heat pump unit 110 hinders the use of hot water due to a decrease in the temperature of the hot water stored in the hot water tank 132, the heat pump unit 110 may reheat the hot water.

  Since the heat pump unit 110 uses a heat exchange cycle, it is possible to save energy and reduce carbon dioxide emissions. Therefore, the hot water supply apparatus 100 can be a hot water supply apparatus with a reduced environmental load compared to the conventional combustion hot water supply apparatus.

  As described above, since carbon dioxide, which is a natural refrigerant, is used as the heat medium in this embodiment, the heat pump unit 110 has a high heat medium between the compression process by the compressor 114 described later and the heat dissipation process by the radiator 116. Perform a supercritical cycle that reaches a critical state. Since the supercritical cycle operates at a high pressure and does not undergo phase change (gas-liquid change) within the operating temperature range, a wide and wide temperature range and large heat transfer can be set. Moreover, since carbon dioxide is a natural refrigerant, it is harmless to the environment. Therefore, it is possible to reduce the load on the environment.

  The heat pump unit 110 includes an evaporator 112, a compressor 114, a radiator 116, and expansion means 118.

  The evaporator 112 performs heat exchange between the heat medium circulating in the heat pump unit 110 and the outside air. Such an evaporator 112 is also called an air heat exchanger. Thereby, the heat medium can absorb the heat of the outside air (in the atmosphere) and evaporate to obtain heat for heating water.

  The compressor 114 compresses the heat medium evaporated by absorbing the heat of the outside air by using electric power. As a result, the heat medium becomes a high pressure state, generates high heat, and heat can be heated in the radiator 116 described later using such heat.

  The radiator 116 heats water supplied from a hot water tank 132 described later, and generates hot water. Such a radiator 116 is also referred to as a water heat exchanger. The radiator 116 performs heat exchange between the heat medium compressed by the compressor 114 and having a high temperature and the water supplied from the hot water tank 132. Thereby, water can be heated using the heat of a heat medium, and hot water can be produced | generated.

  Furthermore, as will be described later, in this embodiment, during the follow-up operation, the radiator 116 is higher when supplying high-temperature water to the follow-up heat exchanger 150 than when supplying high-temperature water to the hot water storage tank 132. High temperature water can be produced. In this case, high-temperature water at a high temperature can be generated by using a heat medium that is more highly compressed by the compressor 114 for heat exchange.

  The expansion unit 118 expands and cools the heat medium after heat exchange with water in the radiator 116 is performed under reduced pressure. Thereby, it becomes possible for this heat medium to absorb the heat of outside air again, and a heat medium can be reused. In the present embodiment, an expansion valve is used as the expansion means 118. However, the present invention is not limited to this, and any expansion medium can be used as long as it can expand and cool the heat medium after heat exchange with water.

  The hot water storage unit 130 stores hot water generated by the heat pump unit 110, and supplies hot water to a hot water supply facility (not shown) such as the bath 200, kitchen, or washroom when the user needs it. The hot water storage unit 130 includes a hot water storage tank 132, a hot water supply pump 134, a hot water supply valve 136, a follow-up heat exchanger 150, a bath circulation pump 138, a high temperature water extraction pump 160, and a medium temperature water extraction pump 162. It includes valves 156a and 156b and a plurality of pipes.

  The hot water storage tank 132 stores hot water generated by the heat pump unit 110. The hot water stored in the hot water storage tank 132 has a temperature distribution, a high temperature region where high temperature water stays in the upper part, a low temperature region where low temperature water stays in the lower part, and an intermediate temperature region where medium temperature water stays in the middle part. Exists.

  The chasing heat exchanger 150 is a heat exchanger for chasing and heating the bath water supplied to the bath 200 from the hot water supply facility. The follow-up heat exchanger 150 performs heat exchange between the high-temperature water supplied by the heat pump unit 110 and the bath water stored in the bath 200. Thereby, the hot water of the bath 200 can be heated using the heat of the hot water, and the hot water can be traced.

  The hot water supply pump 134 is provided on the hot water supply pipe 140 and sends low temperature water (water or hot water) from the lower part of the hot water storage tank 132 to the radiator 116 for circulation.

  The hot water supply valve 136 is a branch portion of the hot water supply pipe 140, and switches the high temperature water supplied from the radiator 116 through the hot water supply pipe 140 to the follow-up pipe 142 or the heat storage pipe 146.

  The bath circulation pump 138 is provided on the bath circulation pipe 164 and sends the bath water of the bath 200 to the heat exchanger 150 for circulation.

  The high-temperature water extraction pump 160 is provided on the high-temperature water extraction pipe 148, and sends high-temperature water from the high-temperature region, which is the upper part of the hot water tank 132, to the mixing valves 156a and 156b for mixing.

  The intermediate temperature water extraction pump 162 is provided on the intermediate temperature water extraction pipe 152, and sends out the intermediate temperature water from the intermediate temperature region, which is the middle part of the hot water storage tank 132, to the mixing valves 156 a and 156 b to be mixed with the above-described high temperature water.

  The mixing valve 156 a is provided at the junction of the high temperature water extraction pipe 148 and the medium temperature water extraction pipe 152. The mixing valve 156b is disposed on the downstream side of the mixing valve 156a, and is provided at the junction of the mixing pipe 154 and the water supply pipe 158. The opening degree of the mixing valves 156a and 156b can be adjusted, and the temperature of the mixed hot water to be mixed and discharged is changed to a temperature desired by the user by changing the ratio of mixing high temperature water, medium temperature water, or feed water. Adjust.

  In the hot water storage unit 130, a plurality of pipes through which hot water flows are arranged. The main pipes include a hot water supply pipe 140, a follow-up pipe 142, a residual heat pipe 144, a heat storage pipe 146, a high temperature water extraction pipe 148, an intermediate temperature water extraction pipe 152, a mixing pipe 154, and a bath circulation pipe 164. A water supply pipe 158 is provided.

  The hot water supply pipe 140 is a pipe that circulates water or hot water in the hot water storage tank 132 and the radiator 116 of the heat pump unit 110. The hot water supply pipe 140 includes a feed pipe 140a and a return pipe 140b. One end of the feed pipe 140 a is connected to the lower part of the hot water storage tank 132, and the other end is connected to the inlet of the radiator 116, and the low temperature water at the lower part of the hot water storage tank 132 is sent to the radiator 116. One end of the return pipe 140b is connected to the outlet of the radiator 116, and the other end is connected to the hot water supply valve 136. The hot water generated in the radiator 116 is passed through the hot water supply valve 136, the follow-up pipe 142 or the heat storage pipe. 146.

  The follow-up pipe 142 is connected to the hot water supply valve 136, and supplies the hot water supplied to the hot water supply valve 136 through the radiator 116 and the hot water supply pipe 140 to the follow-up heat exchanger 150.

  One end of the residual heat pipe 144 is connected to the outlet of the follow-up heat exchanger 150 and the other end is connected to an intermediate temperature region that is the middle part of the hot water storage tank 132. The remaining heat water after the heat exchange by the follow-up heat exchanger 150 is Return to the middle temperature range of the hot water tank 132.

  The heat storage pipe 146 is connected to the hot water supply valve 136, and supplies the hot water supplied to the hot water supply valve 136 through the radiator 116 and the hot water supply pipe 140 to the hot water storage tank 132. The heat storage pipe 146 is connected to the upper side of the hot water tank 132 and supplies high temperature water to the upper high temperature region of the hot water tank 132.

  The high temperature water extraction pipe 148 is connected to a high temperature region that is an upper part of the hot water storage tank 132, takes out the high temperature water from the hot water storage tank 132, and supplies it to the mixing valves 156 a and 156 b. The amount of hot water taken out by the hot water take-out pipe 148 is adjusted by the opening degree of the mixing valves 156a and 156b.

  The intermediate temperature water extraction pipe 152 is connected to an intermediate temperature region that is an intermediate part of the hot water storage tank 132, extracts intermediate temperature water from the intermediate temperature region, and supplies it to the mixing valve 156a. Similarly to the high temperature water extraction pipe 148, the amount of intermediate temperature water extracted by the intermediate temperature water extraction pipe 152 is adjusted by the opening degree of the mixing valve 156a.

  The mixing pipe 154 is also provided with a mixing valve 156 b connected to the water supply pipe 158. In this embodiment, the mixing valve 156b is disposed on the downstream side of the mixing valve 156a on the mixing pipe 154, but may be disposed on the upstream side. When the user mainly designates a temperature lower than the medium temperature water, the opening degree of the mixing valves 156a and 156b is adjusted to generate hot water with an appropriate temperature.

  Normally, even in the hot water storage tank 132, the hot water is gradually radiated and mixed with the low temperature water below by convection or heat transfer to raise the temperature of the low temperature water below. However, since the intermediate temperature water extraction pipe 152 actively consumes the intermediate temperature water in the hot water storage tank 132, the consumption in the hot water storage tank 132 can be increased without increasing the temperature of the low temperature water.

  In other words, the amount of water supply (water supply) corresponding to the amount of consumption to the lower part of the hot water storage tank 132 by the water supply pipe 158 can be increased. Thereby, the heat radiator 116 can heat not the hot water whose temperature is reduced due to heat dissipation (hot water having a temperature higher than that of the feed water) but the water supply having a lower temperature. From these things, COP of the hot water supply apparatus 100 can be further improved.

  The mixing pipe 154 is connected to the mixing valves 156a and 156b, and supplies the mixed hot water adjusted to the temperature desired by the user by the mixing valves 156a and 156b to the hot water supply facility.

  The water supply pipe 158 is connected to the lower part of the hot water storage tank 132 and supplies supplementary water (water supply) into the hot water storage tank 132. The amount of water supplied through the water supply pipe 158 is adjusted according to the amount of hot water consumed in the hot water storage tank 132.

  The bath circulation pipe 164 is a pipe that circulates bath water between the follow-up heat exchanger 150 and the bath 200. The bath circulation pipe 164 includes a bath water feed pipe 164a and a bath water return pipe 164b. The bath water feed pipe 164 a has one end connected to the bath 164 and the other end connected to the inlet of the follow-up heat exchanger 150, and sends the bath water filled in the bath 200 to the follow-up heat exchanger 150. One end of the bath water return pipe 164 b is connected to the outlet of the follow-up heat exchanger 150 and the other end is connected to the bath 200, and supplies hot water that has been chased in the follow-up heat exchanger 150 to the bath 200.

(Driving driving)
In the case of normal operation in which hot water is generated and stored in the hot water supply apparatus 100, first, as shown by the black arrow in FIG. 1A, the low temperature hot water below the hot water tank 132 is fed to the feed pipe 140a (hot water supply pipe 140). Through the heat sink 116. The low-temperature hot water becomes high-temperature water by heat exchange with the heat medium in the radiator 116. The high-temperature water generated in the radiator 116 is supplied from the return pipe 140b (hot-water supply pipe 140) to the high-temperature area above the hot-water tank 132 through the hot-water supply valve 136 and stored. When the bath 200 is used, hot water of an appropriate temperature is supplied to the bath 200 from the hot water filled pipe 155 branched from the mixing pipe 154.

  FIG.1 (b) is a figure explaining the chasing operation of the hot water storage type hot-water supply apparatus concerning this embodiment. In the present embodiment, when performing the chasing operation of the bath 200, the high-temperature water generated by the radiator 116 as described above is fed from the hot water supply valve 136 as indicated by the black arrow shown in FIG. 142 is supplied to the follow-up heat exchanger 150. After exchanging heat with the bath water of the bath 200, residual heat water, which is high-temperature water after heat exchange, is discharged from the follow-up heat exchanger 150. Then, the discharged residual heat water is returned to the intermediate temperature range of the hot water storage tank 132 through the residual heat pipe 144.

  In the above configuration, the first feature of the present embodiment is to return the remaining heat water after heat exchange to the middle temperature range of the hot water storage tank 132. Residual hot water that has lost heat in the follow-up heat exchanger 150 does not drop below the temperature of the warm bath (eg, 30 ° C.) even if the heat is lost. For this reason, if surplus water is returned to the lower part of the hot water storage tank 132, the temperature of the lower part will rise. However, by returning to the middle temperature range as in the above configuration, the low temperature water staying in the low temperature range below the hot water tank 132 is not warmed.

  The second feature of the present embodiment is that the hot water heated by the heat pump unit 110 is directly used instead of the hot water in the hot water storage tank 132 when performing the follow-up. Even if high-temperature water already stored in the hot water storage tank 132 is used, the capacity of the hot water storage tank 132 installed for home use is not large, so that additional operation of the heat pump unit 110 is forced to follow up. There are many cases. Therefore, even if the heat pump unit 110 is moved for chasing, use energy is not wasted. Rather, by using the heated water directly, the responsiveness is much higher than heating the entire hot water tank 132, and it is only necessary to operate as much as necessary rather than heating the entire hot water tank 132. be able to. Note that “good responsiveness” means that the hot water in the bath 200 can be quickly reheated.

  Furthermore, the third feature of the present embodiment is that high temperature water having a temperature higher than that during normal operation is generated during the pursuit. As a result, chasing can be completed in a shorter time, the amount of water used can be reduced, and responsiveness can be improved. In addition, since the temperature of the remaining hot water after the heat exchange is also increased, even if it is returned to the middle temperature range of the hot water storage tank 132, the specific gravity is lighter than that of the low temperature water, so that it does not flow into the low temperature area. Does not reduce the overall temperature.

  By these, without lowering the low temperature water in the lower part of the hot water tank 132, it is possible to prevent the COP from being lowered due to the rise in the temperature of the water entering the heat pump unit 110, thereby improving the COP.

  By the way, operating the heat pump unit 110 at a high temperature has a concern that the COP is lowered. However, as will be described below, compared to a case where the temperature of the lower part of the hot water tank 132 rises, the decrease in COP can be suppressed.

FIG. 2 is a diagram for explaining a device configuration of a comparative example, and FIG. 3 is a Mollier diagram (TH diagram) of CO ₂ which is a heat medium of the heat pump unit. With reference to the example of FIG. 3 and a comparative example, a description will be given of a decrease in COP due to an increase in the incoming water temperature of the heat pump unit 110.

  In the embodiment, it is assumed that the apparatus configuration is the configuration described above, and the heating is performed from 9 ° C., which is a feed water temperature, to 90 ° C., which is a higher temperature than during normal operation. In the embodiment, A → B is compression (isentropic change), B → C is heat release (isobaric change), C → D is expansion (isoenthalpy change), and D → A is evaporation (isobaric change). The outside air temperature is 7 ° C according to winter conditions, and the water supply temperature is 9 ° C.

  As shown in FIG. 2, the comparative example returns to the bottom of the hot water tank 132 from the hot water tank 132, the hot water pipe 242 that supplies high temperature water to the hot water exchanger 150, and the hot water exchanger 150. And a residual heat pipe 244. In the comparative example, it is assumed that the temperature of the lower part of the hot water tank 132 is raised to 28 ° C. by the chasing, and is heated to 65 ° C., which is the temperature of the high-temperature water during normal operation. In FIG. 3, the state change of the comparative example is described as A ′, B ′, C ′, and D ′.

  In the hot water storage hot water supply apparatus using the heat pump as described above, the temperature D of the heat medium (wet steam) expanded and cooled by the expansion valve is affected by the outlet temperature (heat pump unit) of the radiator 116. For example, as shown in the comparative example, when low-temperature water whose temperature has increased to about 28 ° C. (should be called medium-temperature water) is supplied to the radiator 116 and heated, the heat medium of the heat pump unit 110 that performs heat exchange Is sent to the expansion means 118 (expansion valve) without being at least 28 ° C. or lower. Although the expansion valve is depressurized and expanded and cooled, the enthalpy H remains constant (C ′ → D ′).

  Then, COP (heat radiation ΔI2 / pump work ΔL2) when medium temperature water near 28 ° C. is heated to high temperature water of about 65 ° C. as in the comparative example is 90 ° C. of low temperature water near 9 ° C. as in the example. It is significantly lower than COP (heat dissipation ΔI1 / pump work ΔL2) when heated to a high temperature water. That is, it can be seen that heating the low-temperature water to high-temperature water having a higher temperature than during normal operation can improve the COP than heating the medium-temperature water to high-temperature water during normal operation.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  INDUSTRIAL APPLICABILITY The present invention can be used in a hot water storage type hot water supply apparatus that stores hot water generated by heating water and supplies the stored hot water to a hot water supply facility.

DESCRIPTION OF SYMBOLS 100 ... Hot water supply apparatus 110 ... Heat pump unit 112 ... Evaporator 114 ... Compressor 116 ... Radiator 118 ... Expansion means 130 ... Hot water storage unit 132 ... Hot water storage tank 134 ... Hot water supply pump 136 ... Hot water supply valve 138 ... Bath circulation pump 140 ... Hot water supply piping 142 ... additional pipe 144 ... residual heat pipe 146 ... heat storage pipe 148 ... high temperature water extraction pipe 150 ... additional heat exchanger 152 ... intermediate temperature water extraction pipe 154 ... mixing pipe 155 ... hot water filled pipes 156a, 156b ... mixing valve 158 ... water supply pipe 160 ... High temperature water extraction pump 162 ... Medium temperature water extraction pump 164 ... Bath circulation piping 200 ... Bath 242 ... Follow-up piping 244 ... Remaining heat piping

Claims (4)

A hot water generator that generates high temperature water by heating low temperature water;
A hot water storage tank for storing hot water,
A follow-up heat exchanger that heats the bath water,
A heat storage pipe connected from the hot water generator to the hot water tank;
A follow-up pipe connected to the follow-up heat exchanger from the hot water generator, and a keep-heat pipe leading the remaining heat water after heat exchange from the follow-up heat exchanger to the hot water storage tank;
With
The hot water storage type hot water supply apparatus, wherein the remaining heat pipe is connected to an intermediate temperature region that is a midway in the height direction of the hot water storage tank.   The hot water generator generates high temperature water at a higher temperature when supplying high temperature water to the follow-up heat exchanger than when supplying high temperature water to the hot water storage tank. The hot water storage type hot water supply apparatus described. The hot water storage water heater is
A water supply pipe for supplying water to the lower part of the hot water tank;
A high-temperature water extraction pipe for extracting high-temperature water from a high-temperature region that is the upper part of the hot water tank in the height direction;
An intermediate temperature water extraction pipe for extracting intermediate temperature water from the intermediate temperature range;
From the high-temperature water extraction pipe, the medium-temperature water extraction pipe and the water supply pipe, high-temperature water or medium-temperature water, or a mixing pipe for mixing and feeding hot water,
The hot water storage type hot water supply apparatus according to claim 1 or 2, further comprising:   The hot water storage hot water supply device according to any one of claims 1 and 3, wherein the hot water generator is a heat pump.

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