JP5186235B2 - Hot water storage hot water supply system - Google Patents

Description

  The present invention relates to a hot water storage hot water supply system in which hot water in a hot water storage tank or hot water in an intermediate temperature layer is mixed with hot water and mixed to supply hot water.

  2. Description of the Related Art Conventionally, there is a hot water storage type hot water supply system in which water is boiled into hot water by a heat source device such as a heat pump and stored in a hot water storage tank, and the stored hot water is supplied. The hot water in the hot water storage tank is the hottest layer with the highest temperature, and the hot water from the hot layer is discharged and mixed with the cold water from the water supply pipe. . When the hot water is discharged from the upper part of the hot water storage tank, the hot water is supplied to the lower part of the hot water storage tank. The heat pump has the characteristic that the efficiency decreases as the boiling temperature rises. Therefore, when hot water is supplied, hot water heated to high temperature is mixed with low temperature water and hot water is supplied to the hot water system. The overall energy efficiency of is low. In order to increase the energy efficiency of hot water supply for medium temperature hot water, a hot water storage type hot water supply system that stores hot water in a hot water storage tank coexisting with a high temperature layer and an intermediate temperature layer and discharges hot water from the intermediate temperature layer of the hot water storage tank is known. (For example, refer to Patent Document 1).

  Such a conventional hot water storage type hot water supply system includes, for example, a hot water storage tank that stores hot water in a coexistence of a high temperature layer and an intermediate temperature layer, and a heat source device that boils hot water in the hot water storage tank. A middle temperature hot water outlet is provided in the middle layer of the hot water storage tank in order to discharge the middle temperature hot water from the middle temperature layer. The hot water in the high temperature layer or the medium temperature hot water in the intermediate temperature layer is mixed with the feed water, and the mixed hot water at the set temperature of the mixed hot water is supplied (mixed hot water).

When mixing hot water with the same hot water temperature, mixing hot water with hot water is more energy efficient than mixing hot water with hot water. In order to mix the medium temperature hot water with the water supply and supply the mixed hot water at the set temperature, the hot water temperature of the intermediate temperature layer needs to be higher than the set temperature of the mixed hot water. However, the hot water temperature in the intermediate temperature layer is lowered by the hot water in the intermediate temperature layer in the hot water storage tank. The set temperature of the mixed hot water is changed by the user depending on the purpose of using the mixed hot water. If the hot water temperature of the intermediate temperature layer becomes lower than the set temperature of the mixed hot water due to a decrease in the hot water temperature of the intermediate temperature layer or a setting change that increases the set temperature of the mixed hot water, the hot water of the intermediate temperature layer cannot be used for the mixed hot water. In that case, since hot water is mixed with hot water and mixed hot water is supplied, the energy efficiency of the mixed hot water decreases.
JP-A-60-269

  The present invention has been made to solve such a problem, and in a hot water storage hot water supply system that mixes hot water stored in a hot water storage tank with hot water stored in a hot water storage tank and mixed hot water, The purpose is to increase the energy efficiency of mixed hot water by making the hot water temperature usable for mixed hot water.

  In order to achieve the above object, the invention described in claim 1 comprises a hot water storage tank for storing hot water in which a high temperature layer and an intermediate temperature layer coexist, and a heat source device for boiling the hot water in the hot water storage tank. In a hot water storage hot water supply system that mixes and supplies hot water in a hot water layer or the intermediate temperature layer with hot water, based on the hot water temperature detected by the hot water temperature detecting means and the hot water temperature detected by the hot water temperature detecting means And a controller for controlling boiling of hot water by the heat source device, and when the hot water temperature of the intermediate temperature layer detected by the hot water temperature detecting means is less than a set temperature of the mixed hot water supply, the heat source device The hot water in the intermediate temperature layer is raised by boiling high temperature hot water and feeding it to the intermediate temperature layer.

The invention according to claim 2 comprises a hot water storage tank that stores hot water in a coexistence of a high temperature layer and an intermediate temperature layer, and a heat source device that boils the hot water in the hot water storage tank. In a hot water storage hot water supply system that mixes and mixes hot water with hot water, hot water temperature detecting means for detecting the hot water temperature of the hot water storage tank, and hot water generated by the heat source unit based on the hot water temperature detected by the hot water temperature detecting means. And a controller that controls boiling, and when the hot water temperature of the intermediate temperature layer detected by the hot water temperature detecting means is less than a set temperature of the mixed hot water, the heat source machine supplies hot water of the intermediate temperature layer. Sucking, boiling the sucked hot water, and feeding the heated hot water to the intermediate temperature layer , circulating the hot water between the heat source machine and the intermediate temperature layer , boiling the intermediate temperature layer To increase the temperature of water.

  According to the invention of claim 1, when the hot water temperature of the intermediate temperature layer is less than the set temperature of the mixed hot water supply, the hot water temperature of the intermediate temperature layer is raised by performing a small amount of high temperature boiling on the intermediate temperature layer. The hot water of the middle temperature layer can be made a hot water temperature that can be used for mixed hot water supply. Therefore, the utilization of hot water in the middle temperature layer is not lowered, and the energy efficiency of the mixed hot water supply is increased.

  According to the second aspect of the present invention, when the hot water temperature of the intermediate temperature layer is less than the set temperature of the mixed hot water supply, the hot water of the intermediate temperature layer is heated by the heat source machine and the circulating operation is performed to raise the hot water temperature of the intermediate temperature layer. Therefore, the hot water of the middle temperature layer can be made a hot water temperature that can be used for the mixed hot water supply. Therefore, the utilization of hot water in the middle temperature layer is not lowered, and the energy efficiency of the mixed hot water supply is increased.

  Hereinafter, a hot water storage type hot water supply system (hereinafter referred to as a hot water supply system) according to a first embodiment of the present invention will be described with reference to FIG. The hot water supply system 10 includes a hot water storage tank 11 for storing hot water in a high temperature layer and an intermediate temperature layer, and a heat source unit 13 for boiling the hot water in the hot water storage tank 11. Mix hot water. In the hot water storage tank 11, temperature stratification is formed in the internal hot water by the specific gravity of the hot water. That is, the hottest high temperature layer coexists in the upper layer of hot water in the hot water storage tank 11, and the intermediate temperature layer coexists with the lower temperature medium temperature layer, and the hot water is stored in the high temperature layer and the intermediate temperature hot water is stored in the intermediate temperature layer, respectively. The hot water supply system 10 may include a hot water storage tank 11 in addition to the hot water storage tank 11, for example, a hot water storage tank 12 that stores hot water by forming a high temperature layer therein. The hot water storage tank 12 can increase the hot water supply capacity of the hot water.

  The hot water storage tank 11 is connected to the water supply pipe 50a in the lower layer portion, receives low temperature water supply, and forms a low temperature layer. The heat source unit 13 is connected to the lower layer portion of the hot water storage tank 11 by a pipe 51a, and sucks and heats the low temperature hot water in the low temperature layer by a built-in hot water supply pump 13P. The hot water outlet of the heat source unit 13 is connected to the switching valve 16a by a pipe 51c. The switching valve 16a switches the hot water supply destination from the heat source device 13 to a pipe 51d connected to the middle layer part of the hot water storage tank 11 and a pipe 51e connected to the upper layer part. The high temperature hot water from the hot water storage tank 11 is sent to the high temperature hot water discharge pipe 52a. The high temperature hot water supply pipe 52a supplies hot water to a high temperature hot water supply port (not shown). When the hot water supply system 10 includes the hot water storage tank 12, the hot water outlet is switched between the hot water storage tank 11 and the hot water storage tank 12 by the switching valve 16 c.

  An intermediate temperature hot water outlet 11a is provided in the middle layer of the hot water storage tank 11, and an intermediate temperature hot water outlet pipe 52b is connected to the intermediate temperature hot water outlet 11a. The intermediate temperature hot water discharge pipe 52b is connected to the switching valve 16d. The switching valve 16d is also connected to a pipe 51h branched from the high-temperature hot-water tap pipe 52a, and switches between medium-temperature hot water and high-temperature hot water and sends the hot water to the mixing valve 17. The mixing valve 17 is connected to the piping from the switching valve 16d and the water supply pipe 50c. The mixing valve 17 mixes the hot water from the switching valve 16d and the water supply from the water supply pipe 50c to create mixed hot water. (Not shown).

  Further, the hot water supply system 10 includes a hot water temperature sensor 15 as hot water temperature detecting means for detecting the hot water temperature of the hot water storage tank 11, and a control unit 14 that controls the heat source device 13 based on the hot water temperature detected by the hot water temperature sensor 15. With. The hot water temperature sensor 15 includes, for example, a plurality of temperature sensors arranged in the vertical direction inside or on the surface of the hot water storage tank 11, and detects the hot water temperature of the hot water and the intermediate temperature water stored in the hot water storage tank 11. . When the hot water supply system 10 includes the hot water storage tank 12, the hot water temperature sensor 15 also detects the hot water temperature of the high temperature layer of the hot water storage tank 12. The detection result of the hot water temperature is input to the control unit 14. The control part 14 consists of CPU etc., and controls the hot water supply system 10 whole including control of the heat-source equipment 13 and the switching valves 16a thru | or 16d. The control unit 14 is connected to an input unit 18 for inputting a set temperature or the like of the mixed hot water supply. The input unit 18 includes, for example, a button (not shown), and the user can input a desired set temperature to the control unit 14 by pressing the button. The set temperature is stored, for example, in a memory read by the CPU.

  Next, control of the hot water supply system 10 configured as described above will be described. The control unit 14 has a set temperature for each of boiling of high-temperature hot water, boiling of medium-temperature hot water, and hot water supply of mixed hot water. The heat source unit 13 raises the high-temperature hot water to a high-temperature boiling temperature and raises the medium-temperature hot water to a medium-temperature boiling temperature. Control is performed so that the hot water is heated to a temperature, mixed hot water or medium hot water, and feed water are mixed to make a mixed hot water having a set temperature of the mixed hot water. The user of the hot water supply system 10 can input a desired set temperature of the mixed hot water supply via the input unit 18. When the hot water temperature of the intermediate temperature layer detected by the hot water temperature sensor 15 is less than the set temperature of the mixed hot water supply, the heat source unit 13 raises the hot water and sends it to the intermediate temperature layer of the hot water storage tank 11.

  A hot water supply route during boiling will be described. The control unit 14 switches the switching valve 16a to the middle layer side (the piping 51d side) of the hot water storage tank 11. The control unit 14 drives the hot water supply pump 13P of the heat source unit 13, sucks low temperature hot water from the lower layer of the hot water storage tank 11 to the heat source unit 13, boiles high temperature hot water, and turns the high temperature hot water through the switching valve 16a. Hot water is supplied to the pipe 51d and supplied to the intermediate temperature layer stored in the middle layer of the hot water storage tank 11 (refer to the hot water supply path indicated by the thick line in FIG. 1). Since the boiling temperature of hot water is high (high temperature boiling), the hot water temperature in the intermediate temperature layer can be raised by a small amount of boiling.

  As described above, when the hot water temperature in the intermediate temperature layer is less than the set temperature of the mixed hot water, the hot water supply system 10 raises the hot water temperature in the intermediate temperature layer by performing a small amount of high temperature boiling on the intermediate temperature layer. The hot water of the layer can be raised to a hot water temperature that can be used for mixed hot water supply. Therefore, the utilization of hot water in the middle temperature layer is not lowered, and the energy efficiency of the mixed hot water supply is increased.

  When boiling hot water in the hot water storage tank 11, the control unit 14 switches the switching valve 16a to the upper layer side (pipe 51e) of the hot water storage tank 11, and switches the switching valve 16b to the hot water storage tank 11 side. The control unit 14 drives the hot water supply pump 13P of the heat source device 13, sucks low temperature hot water from the lower layer portion of the hot water storage tank 11 into the heat source device 13, and sends the boiled high temperature hot water to the switching valve 16a through the pipe 51c. The sent hot water flows into the pipe 51e via the switching valve 16a and is fed to the upper hot layer of the hot water storage tank 11. When boiling hot water in the hot water storage tank 12, the switching valve 16b is switched to the hot water storage tank 12 side.

  Next, a hot water supply path during hot water supply of the hot water supply system 10 will be described. When mixed hot water is supplied, if the hot water temperature in the intermediate temperature layer in the hot water storage tank 11 detected by the hot water temperature sensor 15 is equal to or higher than the set temperature of the mixed hot water, the hot water is discharged from the intermediate temperature layer. The control unit 14 switches the switching valve 16d to the intermediate temperature hot water discharge piping 52b side, and stops hot water from the upper layer portion of the hot water storage tank 11. When the mixed hot water outlet is opened, the supply water enters the lower layer of the hot water storage tank 11 from the water supply pipe 50a due to the supply water pressure, and the intermediate hot water is sent from the intermediate layer to the intermediate hot water outlet piping 52b via the switching valve 16d. It is sent to the mixing valve 17. The medium temperature hot water from the medium temperature hot water discharge pipe 52b is mixed with the water supplied from the water supply pipe 50c by the mixing valve 17 and mixed hot water is supplied.

  Normally, hot water is discharged from the middle temperature zone and mixed hot water is supplied. However, the hot water temperature in the middle temperature layer in the hot water storage tank 11 is lower than the set temperature of the mixed hot water due to a large amount of mixed hot water. When hot water in the middle temperature layer cannot be used, the hot water and hot water in the hot water storage tank 11 or hot water storage tank 12 are mixed by the mixing valve 17 and mixed hot water is supplied. When mixing hot water and hot water in the hot water storage tank 11, the control unit 14 switches the switching valve 16d to the piping 51h side and switches the switching valve 16c to the hot water storage tank 11 side. Due to the feed water pressure, the high temperature hot water in the high temperature layer is sent to the high temperature hot water tap piping 52a and the piping 51h via the switching valve 16c, sent to the mixing valve 17 via the switching valve 16d, and mixed with the feed water by the mixing valve 17. Mixed hot water. When mixing hot water and hot water in the hot water storage tank 12, the switching valve 16 c is switched to the hot water storage tank 12 side.

  When hot water is discharged from the hot water storage tank 11 and hot water is supplied, the control unit 14 switches the switching valve 16c to the hot water storage tank 11 side (the piping 51g side) to supply hot water. When the high temperature hot water outlet is opened, the supply water enters the lower layer of the hot water storage tank 11 from the water supply pipe 50a due to the supply water pressure, and the high temperature hot water in the hot water storage tank 11 passes through the switching valve 16c through the high temperature hot water hot water supply pipe 52a. Hot water is supplied to the hot outlet. When hot water is discharged from the hot water storage tank 12 to supply hot water, the control unit 14 switches the switching valve 16c to the hot water storage tank 12 side (pipe 51f side).

  Next, a hot water supply system according to a second embodiment of the present invention will be described with reference to FIG. The hot water supply system 20 of the present embodiment is different from the hot water supply system 10 of the first embodiment in that it includes a return pipe 53 for returning hot water from the middle layer of the hot water storage tank 11 to the heat source unit 13. This is the same as the hot water supply system 10. The hot water supply system 20 includes a hot water storage tank 11 that stores hot water in a coexistence of a high temperature layer and an intermediate temperature layer, and a heat source unit 13 that boils the hot water in the hot water storage tank 11, and mixes hot water in the high temperature layer or medium temperature layer with the water supply. And mix hot water. Further, the hot water supply system 20 includes a hot water temperature sensor 15 as hot water temperature detecting means for detecting the hot water temperature of the hot water storage tank 11, and a control unit 24 that controls the heat source device 13 based on the hot water temperature detected by the hot water temperature sensor 15. With.

  The return pipe 53 provided in the hot water supply system 20 has one end connected to the middle layer portion of the hot water storage tank 11 and the other end connected to the switching valve 16e, and returns hot water from the middle layer portion to the heat source unit 13. A return pipe 53 from the middle layer and a pipe 51a from the lower layer are connected to the switching valve 16e, and the medium temperature hot water from the return pipe 53 and the low temperature hot water from the pipe 51a are switched by the switching valve 16e. Sucked.

  In the hot water supply system 20 configured as described above, when the hot water temperature of the intermediate temperature layer detected by the hot water temperature sensor 15 is less than the set temperature of the mixed hot water, the heat source device 13 is located between the heat source device 13 and the intermediate temperature layer. The hot water temperature in the middle temperature layer is raised by circulating and boiling water.

  The hot water supply path when circulating hot water and boiling is explained. The control unit 24 switches the switching valve 16a to the middle layer side (the piping 51d side) of the hot water storage tank 11, and switches the switching valve 16e to the return piping 53 side. The control unit 24 drives the hot water supply pump 13P of the heat source unit 13, sucks the hot water in the middle temperature layer of the hot water storage tank 11 from the return pipe 53 to the heat source unit 13, and supplies the boiled hot water to the pipe via the switching valve 16a. The hot water is supplied to 51d and supplied to the middle temperature layer in the hot water storage tank 11 (refer to the hot water supply path indicated by the thick line in FIG. 2). Thus, the hot water in the intermediate temperature layer is circulated between the heat source unit 13 and the intermediate temperature layer of the hot water storage tank 11 to be re-cooked (refreshing circulation operation).

  As described above, in the hot water supply system 20 of the present embodiment, when the hot water temperature of the intermediate temperature layer is less than the set temperature of the mixed hot water supply, the hot water of the intermediate temperature layer is additionally cooked by the heat source unit 13 and the circulation operation is performed. Since the temperature is raised, the hot water in the middle temperature layer can be made a hot water temperature that can be used for the mixed hot water supply. Therefore, the utilization of hot water in the middle temperature layer is not lowered, and the energy efficiency of the mixed hot water supply is increased.

  The present invention is not limited to the configuration of each of the embodiments described above, and various modifications can be made without departing from the scope of the invention. For example, the heat source unit 13 is not limited to a heat pump, and may be a combustion type water heater.

The block diagram of the hot water storage type hot-water supply system which concerns on the 1st Embodiment of this invention. The block diagram of the hot water storage type hot-water supply system which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

10, 20 Hot water storage type hot water supply system 11 Hot water storage tank 13 Heat source machine 14, 24 Control unit 15 Hot water temperature sensor 18 Input unit 53 Return piping

Claims (2)

A hot water storage tank that stores hot water in the high temperature and medium temperature layers,
A heat source machine for boiling the hot water in the hot water storage tank,
In the hot water storage hot water supply system for mixing and supplying hot water mixed with hot water in the high temperature layer or the intermediate temperature layer,
Hot water temperature detecting means for detecting the hot water temperature of the hot water storage tank;
A controller that controls boiling of hot water by the heat source unit based on the hot water temperature detected by the hot water temperature detecting means;
When the hot water temperature of the intermediate temperature layer detected by the hot water temperature detection means is less than the set temperature of the mixed hot water supply, the heat source machine boils high temperature hot water and sends the hot water to the intermediate temperature layer to supply the intermediate temperature layer. A hot water storage hot water supply system characterized by raising the hot water temperature. A hot water storage tank that stores hot water in the high temperature and medium temperature layers,
A heat source machine for boiling the hot water in the hot water storage tank,
In the hot water storage hot water supply system for mixing and supplying hot water mixed with hot water in the high temperature layer or the intermediate temperature layer,
Hot water temperature detecting means for detecting the hot water temperature of the hot water storage tank;
A controller that controls boiling of hot water by the heat source unit based on the hot water temperature detected by the hot water temperature detecting means;
When the hot water temperature of the intermediate temperature layer detected by the hot water temperature detecting means is less than the set temperature of the mixed hot water supply, the heat source device sucks the hot water of the intermediate temperature layer, boils the sucked hot water, Hot water storage type hot water supply, wherein hot water is circulated and boiled between the heat source unit and the intermediate temperature layer by feeding the raised hot water to the intermediate temperature layer to raise the temperature of the intermediate temperature layer system.

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