JP2009250542A - Water heater - Google Patents

Abstract

To provide a water heater having a simple and hygienic system, no noise at the time of water supply, and high hot water filling and reheating performance to a bathtub.
A hot water supply device (S) supplies hot water from a first outlet (10) at the top of a hot water storage tank (1) by a hot water circulation pump (18), exchanges heat through the primary side of a hot water supply heat exchanger (4), Circulation circuits 41, 42, 44 for heating returned to the lower part, a hot water supply circuit for introducing tap water to the secondary side of the hot water supply heat exchanger 4, heating it to a predetermined set temperature and supplying it to the hot water supply point 19, A hot water filling circuit that supplies hot water, which is mixed at a predetermined set temperature by the first mixing valve 14, with hot water from the first outlet 10 at the top of the hot water storage tank 1 and the pressure reducing valve 6 to the bathtub 2. 2Y and the water in the bathtub 2 are circulated in the reheating heat exchanger 24 in the upper part of the hot water tank 1, heat is exchanged between the hot water in the hot water tank 1 and supplied to the bathtub 2. And a recirculation circuit 2P.
[Selection] Figure 1

Description

  The present invention relates to a water heater that heats water in a heat pump unit and uses hot water stored in a hot water storage tank for hot water supply or the like.

As a conventional electric water heater, the electric water heater disclosed in Patent Document 1 has components such as a cistern tank, an overflow switch, and a level switch added for the purpose of avoiding a cross connection because the hot water storage tank is an open type. ing.
The hot water filling is a hot water filling circuit that supplies hot water to the bathtub with a pump because the hot water storage tank is open, and a heat exchanger for reheating is arranged outside the tank. ing.

  In the electric water heater disclosed in Patent Document 2, a member for detecting the mixing temperature is disposed downstream of the second mixing valve for the purpose of controlling the second mixing valve.

The electric water heater disclosed in Patent Document 3 has a configuration in which high-temperature water stays in a reheating heat exchanger in a hot water storage tank.
Japanese Patent No. 3955299 (paragraph 0013, FIGS. 1 to 4 etc.) Japanese Patent No. 3908768 (paragraph 0016, FIGS. 1 to 4 etc.) Japanese Patent Laying-Open No. 2005-69557 (paragraph 0018, FIG. 1, etc.)

By the way, since the electric water heater disclosed by the above-mentioned patent document 1 has various parts added for the purpose of avoiding cross connection, the system becomes complicated. Also, because the tank is open, the water supply comes into contact with the atmosphere, and there is concern about hygiene.
In addition, when tap water is introduced into the cistern tank, there is a water supply noise that falls on the water surface of the cistern tank, so the water supply noise becomes loud and noise may be a problem in areas where tap water pressure is high. is there.

Furthermore, since the hot water filling is a hot water filling circuit that supplies hot water to the bathtub with a pump, it depends on the head of the pump. In a conventional electric water heater, for example, a hot water filling with a set temperature of 42 ° C. and 200 liters is about 20 You need minutes and a relatively long time.
In addition, since the heat exchanger for reheating is outside the tank, heat is dissipated during reheating, and energy is wasted.

  The electric water heater disclosed in Patent Document 2 is provided with a member for detecting the mixing temperature downstream of the second mixing valve, and has a drawback that the number of parts is large.

The electric water heater disclosed in Patent Document 3 has a structure in which high-temperature water stays in the reheating heat exchanger in the hot water storage tank. There is a problem that hot water suddenly comes out and cannot be comfortably chased.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a water heater that has a simple and sanitary system, has no noise during water supply, and has high hot water filling and chasing performance.

  A water heater according to the present invention is a water heater that uses hot water stored in a hot water tank by heating tap water introduced into the hot water tank through a pressure reducing valve in a heat pump unit, and is disposed at the upper part of the hot water tank. A hot water circulation circuit that draws hot water taken out from the first outlet through a hot water supply circulation pump, exchanges heat through the primary side of the hot water supply heat exchanger, and returns the hot water whose temperature has dropped to the bottom of the hot water storage tank, and water supply Water is introduced into the secondary side of the hot water heat exchanger, the hot water supply heat exchanger is heated to a predetermined set temperature by hot water passing through the primary side, and supplied to the hot water supply location, A hot water circuit that supplies hot water, which has been mixed from the hot water taken out from one outlet and tap water introduced through the pressure reducing valve, to the bathtub at a predetermined set temperature, and water in the bathtub or hot water. A follower installed in the upper part of the hot water storage tank A recirculation circuit for recirculation that heats the hot water by circulating in the heat exchanger for heat and indirectly exchanging heat with the hot water in the upper part of the hot water storage tank and supplying the heated hot water to the bathtub Yes.

  ADVANTAGE OF THE INVENTION According to this invention, the system is simple and sanitary, there is no noise at the time of water supply, and hot water supply to a bathtub and high reheating performance can be realized.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
<< First Embodiment >>
FIG. 1 is a configuration diagram illustrating an example of an electric water heater S according to the first embodiment of the present invention.

<Overall configuration of electric water heater S>
As shown in FIG. 1, an electric water heater S according to the first embodiment includes a pipe 7 that is supplied with water from a water supply pipe 22 and a heat pump unit that heats low-temperature tap water supplied from the pipe 7. 8, a hot water storage tank 1 for storing hot water heated by the heat pump unit 8, a hot water filling circuit 2Y for supplying hot water in the hot water storage tank 1 to the bathtub 2, and tap water from the water pipe 22 in the hot water storage tank 1 Heat exchanger 4 that heats and exchanges heat with hot water to generate hot water for hot water supply, and heat exchanger for reheating that heats hot water derived from the bathtub 2 by exchanging heat with hot water in the hot water storage tank 1 A reheating circuit 2P (shown by a thick line in FIG. 4) for extracting the bath water stretched in the bathtub 2 and reheating it with the reheating heat exchanger 24 and returning it to the bathtub 2; Operated by the user to chase, hot water, etc. Lu remote control 45, an operation unit 60 such as a kitchen remote controller 46 is configured and a controller 16 that controls the overall electric water heater S according to the operation instruction or the like from the operation unit 60.

<Outline of operation of electric water heater S>
As shown in FIG. 1, the electric water heater S introduces the tap water supplied from the water pipe 22 into the lower part of the hot water tank 1 through the pipe 7 through the pressure reducing valve 6 and the pipe 23, and introduces it into the hot water tank 1. The treated tap water is introduced into the heat pump unit 8 through the pipe 32, the three-way valve 33, and the pipe 34, heated by the gas cooler of the heat pump unit 8 to obtain hot water, and this hot water is introduced into the upper part of the hot water storage tank 1 through the pipe 35. Yes.

The hot water stored in the hot water storage tank 1 is used to supply the use place, for example, the bathtub 2 or the like through various pipes, to supply hot water from the mixing tap 19, or to replenish the boiling water in the bathtub 2. ing.
When hot water is supplied from the mixing tap 19 in the electric water heater S, tap water supplied from the water pipe 22 is supplied to the hot water supply heat exchanger 4 through the pipe 7 as shown by a thick line in FIG. The hot water is supplied as hot water to the mixing plug 19 through the pipe 36, the accumulator 39, and the pipe 40.

  As shown in the thick line in FIG. 3 representing the hot water filling mode, the hot water filling to the bathtub 2 is taken out of the hot water in the hot water storage tank 1 from the first outlet 10 at the upper part of the hot water storage tank 1 and passed through the pipes 41 and 54. While leading to one mixing valve 14, tap water in the water pipe 22 is introduced into the first mixing valve 14 via the pipe 7 and the pressure reducing valve 6, and the hot water from the hot water storage tank 1 and the water pipe 22 are introduced by the first mixing valve 14. The hot water is adjusted by the degree of mixing with the tap water, and the hot water filling of the bathtub 2 is performed.

  As shown in the thick line in FIG. 4 representing the reheating mode, reheating water in the bathtub 2 is used for reheating the hot water (hot water) or water disposed in the upper part of the hot water storage tank 1. Circulation is performed in the heat exchanger 24, and the reheating is performed by indirectly heating the reheating heat exchanger 24 with the hot water at the top of the hot water storage tank 1.

Hereinafter, the structure of each part of the electric water heater S will be described in detail.
<Heat pump unit 8>
The heat pump unit 8 shown in FIG. 1 absorbs the external heat with a refrigerant such as expanded low-temperature carbon dioxide, and then heats it with the refrigerant compressed to a high temperature and the low-temperature water from the hot water storage tank 1 flowing through the pipe 34. It is a device that exchanges and heats low-temperature water.
The heat pump unit 8 repeatedly expands and compresses the refrigerant, absorbs heat from the outside and heats the low-temperature water, and a circulation pump (not shown) that circulates the low-temperature water in the hot water storage tank 1 flowing through the pipe 34. And.

The heat pump includes a compressor that compresses the refrigerant, a gas cooler (not shown) that heats the low-temperature water by exchanging heat between the compressed high-temperature refrigerant and the low-temperature water from the hot water storage tank 1, and decompresses the refrigerant by expanding the pressure. And an endothermic device that absorbs the heat of the outside air to the refrigerant whose pressure has been reduced and reduced in temperature.
The circulation pump pumps the low-temperature water in the hot water storage tank 1 through the pipes 32 and 34, passes the gas cooler of the heat pump and heats it, and then returns the heated hot water to the upper part of the hot water storage tank 1 through the pipe 35. .

<Hot water storage tank 1>
In the hot water storage tank 1 shown in FIG. 1, tap water from the water pipe 22 is introduced through the pipe 7, the pressure reducing valve 6, and the pipe 23, and the water in the hot water storage tank 1 is supplied with the pipe 32, the three-way valve. 33 and the pipe 34 are led to the heat pump unit 8 and heated by the gas cooler of the heat pump to become hot water, and then led to the upper part of the hot water storage tank 1 through the pipe 35 and stored in the hot water storage tank 1.

The temperature of the hot water in the hot water storage tank 1 becomes higher as it goes from the lower side to the upper side in the vertical direction, that is, the temperature distribution becomes relatively low, medium and high as it goes from the lower part to the upper part in the hot water storage tank 1. For example, the temperature inside the hot water storage tank 1 is about 90 ° C. and the middle portion is about 50 ° C. In addition, the warm water in the intermediate part of the vertical direction in the hot water storage tank 1 is called intermediate warm water.
In the hot water storage tank 1, a plurality of temperature sensors 48, 49, 50, 51, 52 for detecting the temperature of the hot water stored in the vertical direction are arranged from the upper part to the lower part, and these temperature sensors 48, A detection signal indicating the temperature of the hot water in the hot water storage tank 10 detected by 49, 50, 51, 52 is output to the controller 16 and used for controlling the electric water heater S.

<Water filling circuit 2Y>
A hot water filling circuit 2 </ b> Y shown in FIG. 1 is a circuit for supplying hot water stored in the hot water storage tank 1 to the bathtub 2 and filling the bathtub 2 with hot water.
This hot water filling circuit 2Y guides the hot water at the upper part of the hot water tank 1 to the first mixing valve 14 through the pipe 54 branched from the pipe 41 connected to the first outlet 10 at the upper part of the hot water tank 1. In the mixing valve 14, it is mixed with tap water that has passed through the pipe 7, the pressure reducing valve 6, and the pipe 23 from the water pipe 22, and is disposed downstream of the first mixing valve 14 and is controlled to be opened. The first path passing through the pipes 29b and 29a and the second path connected to the pipe 3 through the pipe 29b, the branch part 30, the pipe 25, the pump 27, and the circulation mixing valve 31 In this configuration, the bath 2 is filled with hot water.
Here, the piping 29a is connected to the reheating entrance 2i of the bathtub 2, and the piping 3 is connected to the retreating outlet 2o of the bathtub 2, via the reheating entrance 2i and the retreating outlet 2o. The hot water filling is performed.

<Heat exchanger 4 for hot water supply>
FIG. 2 is a circuit diagram showing a hot water supply operation of the electric water heater S of the first embodiment by bold lines.
The hot water supply heat exchanger 4 shown in FIG. 2 is supplied from the upper part of the hot water storage tank 1 by a hot water supply circulation pump 18 that is controlled to operate when tap water is supplied to the controller 16 from the tap water 22 and the pipe 7. This is a device for performing hot water supply by supplying heat to the mixing plug 19 by heating and exchanging heat with the hot water that is derived and heating the tap water to a predetermined temperature.

The mixing plug 19 is used, for example, for supplying hot water or for showering in a bathroom.
At the time of hot water supply, the tap water introduced from the water pipe 22 through the pipe 7 to the hot water supply heat exchanger 4 is supplied by the hot water supply circulation pump 18 from the first outlet 10 at the upper part of the hot water storage tank 1 through the pipe 41 to the hot water supply heat exchanger 4. After being heated by the hot water at the top of the hot water storage tank 1 introduced into the hot water tank 1, the hot water is supplied as hot water to the mixing plug 19 through the pipe 36, the accumulator 39 and the pipe 40.
On the other hand, in the hot water supply heat exchanger 4, the hot water that is cooled by exchanging heat with tap water and is discharged from the hot water supply heat exchanger 4 is returned to the lower part of the hot water storage tank 1 through the pipe 42 and the hot water supply circulation pump 18. .

<Hot water supply circulation pump 18>
The hot water supply circulation pump 18 shown in FIG. 1 uses an inverter circuit (not shown) of the controller 16 so that the hot water temperature detected by the hot water temperature sensor 37 in the pipe 36 becomes the hot water temperature set by the operation unit 60. The rotation speed is freely controlled.
That is, when the hot water temperature detected by the hot water temperature sensor 37 is lower than the hot water temperature set by the operation unit 60, the controller 16 determines the rotational speed of the hot water circulation pump 18 that circulates hot hot water in the hot water storage tank 1. When the hot water temperature is higher than the hot water temperature set by the operation unit 60 while increasing the amount of heat applied to the tap water to increase the hot water temperature, the controller 16 reduces the rotation speed of the hot water circulation pump 18. The hot water supply circulation pump 18 is controlled so as to reduce the amount of heat applied to the tap water and lower the hot water supply temperature.

<Reheating heat exchanger 24>
The reheating heat exchanger 24 shown in FIG. 1 has, on the inlet 24i side, a pipe 29a, a pipe 25, a pump 27, a circulation mixing valve 31, and a pipe 58 from which the bath water in the bathtub 2 is led, Connected to the outlet 24o side is a pipe 26 for returning to the bathtub 2 the bath water heated and reheated by heat exchange with the high-temperature water in the upper part of the hot water storage tank 1 in the reheating heat exchanger 24.

<Turning circuit 2P>
The reheating circuit 2 </ b> P indicated by the thick line in FIG. 4 is a circuit for retreating the bath water stretched on the bathtub 2.
When reheating, the bath water in the bathtub 2 is led out from the reheating entrance 2i of the bathtub 2 as shown by an arrow in FIG. 4 and connected to the retreating entrance 2i. The reheating outlet 2o connected to the piping 3 through the pump 27, the circulation mixing valve 31, the piping 58, the reheating heat exchanger 24, the piping 26, and the piping 3 disposed in the high-temperature hot water above the hot water storage tank 10. It is comprised so that it may return to the bathtub 2 via.

  The low-temperature bath water in the bathtub 2 is indirectly heat-exchanged with the high-temperature hot water in the upper part of the hot water storage tank 10 in the reheating heat exchanger 24 so that it can be reheated efficiently in a short time. It is configured.

  Here, the reheating temperature is set to the reheating set temperature set by the user using the operation unit 60 such as the bath remote controller 45 or the kitchen remote controller 46, and the hot water before reheating through the pipe 29a by the temperature sensor 56. , And the temperature sensor 59 detects the temperature of the hot water passing through the pipe 26 after the reheating, and inputs each detection signal to the controller 16. Then, in the controller 16, a pump that circulates the water in the bathtub 2 to the reheating heat exchanger 24 until the temperature sensor 56 detects that the temperature of the hot water in the bathtub 2 has reached the set temperature of the user. 27, the operation is controlled to continue the chasing mode. Then, when the temperature of the hot water in the bathtub 2 reaches the set temperature of the user, the operation of the pump 27 is stopped and the reheating mode is ended.

<Operation unit 60>
The operation unit 60 shown in FIG. 1 is a device that allows a user to perform input operations for performing hot water filling, chasing, hot water supply, etc., with the electric water heater S, and is disposed in a bath remote controller 45 or a kitchen. There is a kitchen remote control 46 and the like.
The operation unit 60 can select a filling mode for filling the bathtub 2, a reheating mode for replenishing the bath water in the bathtub 2, a hot water supply mode for supplying hot water from the mixing tap 19, and the like. The temperature can be set such as the temperature of hot water during hot water filling, the temperature of hot water during reheating, the temperature of hot water during hot water supply, and the like.
The operation unit 60 is electrically connected to the controller 16 in a wired or wireless manner, and an input operation to the operation unit 60 by a user is input to the controller 16 as an operation signal.

<Controller 16>
The controller 16 is a control device that electronically controls the electric water heater S, and includes a microcomputer that performs control according to signals detected by various sensors such as the operation unit 60 and the temperature sensor 48, and an operation According to the output signal of the control signal from the microcomputer, the input interface such as an amplifier circuit, an A / D converter circuit, etc. that converts the detection signal detected by the unit 60, various sensors, etc. into an input signal suitable for the microcomputer 3. A drive circuit for driving an actuator such as the hot water supply circulation pump 18 and an output interface such as a relay drive circuit are provided.

  The controller 16 controls various actuators such as the electromagnetic valve 28, the hot water supply pump 27, the circulation pump 18 and the heat pump unit 8 in the electric water heater S according to a program stored in a ROM (Read Only Memory) of the microcomputer, and the hot water Various modes such as tensioning, chasing, and hot water supply are controlled.

<< Details of operation of piping system of electric water heater S >>
Next, operation details of the piping system of the electric water heater S will be described.
<Storage of hot water in hot water storage tank 1>
The tap water is supplied to the hot water storage tank 1 as shown by an arrow along the thick line in FIG. 1 by tap water in the water pipe 22 by, for example, a water pressure of 6 to 8 kg / cm ^2. Is introduced into the lower part of the hot water storage tank 1 through the pipe 23 and the check valve 20 after being reduced to a predetermined pressure, for example, about 2 kg / cm ^2. Is done. The check valve 20 plays a role in preventing the backflow of tap water from the hot water storage tank 1 to the water pipe 40 side.

  The tap water introduced into the hot water storage tank 1 is introduced into the heat pump unit 8 through the pipe 32, the three-way valve 33, and the pipe 34, and heated by a gas cooler (not shown) of the heat pump unit 8 as hot water. It is introduced into the upper part of the hot water storage tank 1 through the pipe 35 and stored in the hot water storage tank 1.

<Hot water supply mode from the mixer tap 19>
Next, hot water supply from the mixing plug 19 in the electric water heater S will be described with reference to FIG.
As shown by a broken line in FIG. 2, the electric water heater S includes a circulation circuit in which hot hot water in the hot water storage tank 1 circulates through the hot water heat exchanger 4, and the hot water from the mixing plug 19 is heated by hot water. Using the exchanger 4, the tap water is heated by heat exchange between the tap water from the water pipe 22 and the hot water from the hot water storage tank 1.

When the user uses the bath remote controller 45 to select the hot water supply mode, for example, a hot water supply mode selection signal is input to the controller 16, the hot water circulation pump 18 is operated by the signal from the controller 16, and the hot water in the upper part of the hot water storage tank 1 is operated. 2 is led out from the first outlet 10 to the hot water supply heat exchanger 4 through the pipe 41, and the hot water heat exchanger 4 exchanges heat with low-temperature tap water to lower the temperature. Hot water is returned to the lower part of the hot water storage tank 1 through the pipe 42.
A check valve 43 in the middle of the path from the first take-out port 10 of the hot water storage tank 1 to the hot water supply heat exchanger 4 serves to prevent natural circulation of the hot water storage tank 1, and the outlet of the hot water supply heat exchanger 4. The check valve 44 in the middle of the path from the hot water storage tank 1 to the lower part of the hot water storage tank 1 serves to prevent the back flow of hot water in the hot water storage tank 1 when the hot water supply circulation pump 18 is replaced.

When hot water is supplied using the hot water supply heat exchanger 4, tap water from the water pipe 22 is introduced into the hot water supply heat exchanger 4 through the pipe 7 by the water pressure, and is heated by the hot water supply heat exchanger 4. The hot tap water is supplied to one side of the mixing plug 19 through the pipe 36, the hot water supply temperature sensor 37, the hot water supply flow rate sensor 38, the accumulator 39, and the pipe 40. And in the mixing plug 19, a user mixes the tap water from the water pipe 22 connected to the other side of the mixing plug 19 and the supplied hot water, and adjusts the temperature of the hot water supply.
Note that the accumulator 39 has a hot water remaining in the accumulator 39 in order to prevent an overshoot phenomenon in which hot water blows out from the faucet of the mixing tap 19 when the hot water flow rate is about 2 to 3 liters / min. It is arranged to mix with water and cool to an appropriate temperature.

  The temperature of the hot water supplied to the mixing tap 19 from the hot water supply heat exchanger 4 of the hot water storage tank unit 5 is the temperature of hot water detected by the tank top temperature sensor 47 using the controller 16 in the hot water storage tank unit 5, Based on the temperature detected by the water temperature sensor 53 of the tap water going from the pipe 22 to the hot water supply heat exchanger 4 through the pipe 7, the flow rate detected by the hot water flow sensor 38, the kitchen remote controller 46, the bath remote controller 45, etc. A hot water storage tank that controls the rotational speed of the hot water supply circulation pump 18 so as to reach a predetermined hot water supply temperature set by the operation unit 60 and flows on the primary side that gives heat to tap water in the hot water supply heat exchanger 4. The flow rate of hot water from 1 is controlled.

  According to this structure, since the high water pressure of the tap water from the water pipe 22 can be utilized, for example, a shower on the third floor is possible, and a pressure reducing valve and a negative pressure breaking valve can be dispensed with. In addition, by introducing tap water depressurized via the pressure reducing valve 6 into the hot water storage tank 1 to provide a sealed hot water supply system, parts such as a cistern tank, an overflow switch, and a level switch are unnecessary, and the system is simplified. At the same time, hygiene concerns are eliminated, and noise during water supply is also eliminated.

<Water filling mode for bathtub 2>
Next, hot water filling to the bathtub 2 in the electric water heater S will be described with reference to FIG. In addition, FIG. 3 is a circuit diagram which shows the hot water filling circuit of the electric water heater S by a thick line.
When the user selects the hot water filling mode using the operation unit 60 such as the kitchen remote controller 46 and the bathroom remote controller 45, the electric water heater S fills the bathtub 2 with water.
When the user selects the hot water filling mode with the operation unit 60, the hot water filling mode selection signal is input from the operation unit 60 to the controller 16, and the normally closed electromagnetic valve 28 is controlled to open by the control of the controller 16. At the same time, the first mixing valve 14 and the circulation adjusting valve 31 are each controlled in the hot water filling mode.

  When the electromagnetic valve 28 is controlled to be opened, the tap water supplied from the water pipe 22 is decompressed by the pressure reducing valve 6 and supplied to the hot water storage tank 1 through the pipe 23 as shown in FIG. The hot hot water in the hot water storage tank 1 is pushed out from the first outlet 10 at the top of the hot water storage tank 1. Then, the hot water pushed out from the first outlet 10 is guided to the first mixing valve 14 through the pipe 54 branched from the pipe 41 as shown by the thick line in FIG. A first path that passes through the pipes 29b and 29a through the electromagnetic valve 28 that is mixed with the tap water passing through the pressure reducing valve 6 and the pipe 23 from the pipe 7 connected to And the pipe 29b, the pipe 25 branched from the pipe 29b, the pump 27, and the second path that continues to the pipe 3 through the circulating mixing valve 31, and hot water is supplied to the bathtub 2 and filled with hot water. Is done.

Here, the temperature of the hot water supplied to the bathtub 2 is controlled by the controller 16 so that the temperature of the hot water detected by the temperature sensor 56 becomes a predetermined bath temperature set by the operation unit 60.
That is, the hot water passing through the pipe 29a at the time of hot water filling by the temperature sensor 56 so that the temperature of the hot water filling becomes the hot water filling temperature set by the user using the operation unit 60 such as the bath remote controller 45, the kitchen remote controller 46 or the like. The temperature is detected, and a detection signal of the detected temperature is input to the controller 16. The controller 16 compares the temperature set by the user with the detected temperature of the temperature sensor 56, and the first mixing valve is set so that both are equal. 14 is performed to adjust the mixing ratio of the hot water from the hot water storage tank 1 and the tap water supplied from the pipe 23 or the like.

The amount of hot water supplied to the bathtub 2 is detected by the flow rate sensor 55, the flow rate detection signal is input to the controller 16, and the controller 16 calculates the predetermined hot water amount. The amount is controlled, and when the predetermined amount of hot water is reached, the solenoid valve 28 is closed and the supply of hot water is stopped.
Further, the water level of the bathtub 2 is detected by the water level sensor 57 to detect the pressure of the hot water in the pipe 25, and this detection signal is input to the controller 16, where the controller 16 calculates the water level by the head and the like to reach a predetermined set water level. Thus, the solenoid valve 28 and the like are controlled.

  In this way, the bathtub 2 is filled with water through the pipe 25 on the downstream side of the branch point 30 of the pipe 29b, the circulation adjusting valve 31, and the pipe 3 on the downstream side of the pipe 26 on the outlet side of the reheating pipe. Thus, the hot water filling is performed with two pipes together with the hot water filling from the pipe 29 a, and the hot water filling is performed with a constant water pressure via the pressure reducing valve 6. Therefore, for example, the hot water filling time can be set to about 13 minutes with a set temperature of 42 ° C. and 200 liters of hot water, and the hot water filling time can be shortened by about 7 minutes compared to the conventional case.

<Chance mode>
Next, replenishment of the bath water in the bathtub 2 in the electric water heater S will be described with reference to FIG.
As shown in FIG. 4, reheating water in the bathtub 2 is performed using a reheating heat exchanger 24.
In the reheating heat exchanger 24, the pipe 25 from the bathtub 2, the pump 27, the circulation mixing valve 31, and the pipe 58 are connected to the inlet 24i side, and the pipe 26 returning to the bathtub 2 is connected to the outlet 24o side. It is connected. When using the reheating heat exchanger 24, the pump 27 is driven by the controller 16, and the bath water is introduced into the reheating heat exchanger 24 through the circulation mixing valve 31 from the pipe 25. In the heat exchanger 24, heat is exchanged between the hot water in the upper part of the hot water storage tank 1 and the introduced bath water.

When the user selects the reheating mode with the operation unit 60 such as the kitchen remote controller 46 or the bathroom remote controller 45, the bathroom 2 is reheated in the electric water heater S.
That is, when the reheating mode is selected by the operation unit 60, a reheating mode selection signal is input from the operation unit 60 to the controller 16. Under the control of the controller 16, the boiling water in the bathtub 2 is reheated. The pump 27 for circulating through is operated, and the circulation mixing valve 31 is controlled to the reheating mode.

  As shown by the arrow in FIG. 4, the bath 27 in the bathtub 2 is operated by the command of the controller 16, and the piping 29 a, the branch portion 30, the piping 25, the pump 27, It is led to the reheating heat exchanger 24 through the circulation mixing valve 31 and the pipe 58, and in the reheating heat exchanger 24, heat is exchanged with the hot water at the upper part of the hot water storage tank 1 to be heated and reheated. After being made, it returns to the bathtub 2 through the piping 26 and the piping 3 and the reheating outlet 2o of the bathtub 2.

Here, the bath water led to the reheating heat exchanger 24 is heated and reheated in the reheating heat exchanger 24 by heat exchange with the hot water at the upper part of the hot water storage tank 1. A large amount of heat is given to the bath water, making it possible to catch up efficiently.
In this case, since the reheating heat exchanger 24 is disposed in the upper part of the hot water storage tank 1, at the start of reheating, in order to prevent high-temperature hot water from being supplied to the bathtub 2, The temperature detection signal of the temperature sensor 59 for detecting the temperature of the heated high-temperature water flowing out from the reheating heat exchanger 24 and the temperature detection signal of the temperature sensor 56 for detecting the return temperature are input to the controller 16. In the controller 16, the opening degree of the circulating and mixing valve 31 is predicted so that the temperature of the heated reflux water returned to the bathtub 2 is 60 ° C. or less, and the opening degree of the circulating and mixing valve 31 is controlled.

According to this configuration, at the start of reheating, the temperature detection signal of the temperature sensor 59 that detects the temperature of the heated hot water flowing out from the reheating heat exchanger 24 and the temperature sensor 56 that detects the return temperature. Based on the temperature detection signal, the opening degree of the circulating mixing valve 31 is controlled so that the temperature of the heated fountain returned to the bathtub 2 is equal to or lower than a predetermined temperature. It is possible to prevent the high-temperature water staying at 24 from being discharged directly to the bathtub.
Further, by circulating the hot water in the bathtub 2 to the reheating heat exchanger 24, heat is indirectly exchanged with the hot water in the upper part of the hot water storage tank 1, and the hot water in the bathtub 2 is discharged. By providing a circulation circuit that performs reheating, it is possible to prevent heat from being wasted from the reheating heat exchanger 24 during reheating and to prevent waste of heat energy.

<< Second Embodiment >>
Next, the electric water heater 2S of 2nd Embodiment of this invention is demonstrated using FIG. In addition, FIG. 5 is a configuration diagram in which an example of the electric water heater 2S according to the second embodiment is indicated by a thick line in a hot water filling circuit.
As shown in FIG. 5, the hot water heater 2S of the second embodiment does not necessarily require hot water as hot as in the upper part of the hot water tank 1 in the hot water filling of the bathtub 2. In addition, a second outlet 12 is provided, and medium temperature water in the hot water storage tank 1 is led to a newly provided second mixing valve 11 through a pipe 13 connected to the second outlet 12. The bath 2 is filled with hot water guided from the upper part of the hot water storage tank 1 for hot water filling.

Since the configuration other than this is the same as that of the electric water heater S according to the first embodiment, the same components are denoted by the same reference numerals, and detailed description thereof is omitted.
The hot water filling circuit in the electric water heater 2S is a second mixing system in which hot hot water at the upper part of the hot water tank 1 is newly provided through a pipe 9 branched from the pipe 41 connected to the first outlet 10 at the upper part of the hot water tank 1. Lead to valve 11. Then, in the second mixing valve 11, hot hot water from the upper part of the hot water tank 1 is mixed with intermediate hot water that has passed through the pipe 13 from the second outlet 12 in the middle portion of the hot water tank 1 in the vertical direction. The mixed warm water is further mixed in the first mixing valve 14 with tap water that has passed through the pressure reducing valve 6 and the piping 23 from the water supply pipe 7, and an electromagnetic valve 28 disposed downstream of the first mixing valve 14 is provided. Open the bathtub 29b, the first path passing through the pipe 29a, and the second path passing through the pipe 29b, the branch part 30, the pipe 25, the pump 27, the circulation mixing valve 31 and the second path passing through the pipe 3 Fill the 2 with hot water.

According to the above configuration, the hot water storage tank 1 has, for example, the hot water storage tank 1 by providing the second outlet 12 for deriving and supplying the intermediate water at the intermediate temperature in the hot water storage tank 1 at the vertical intermediate portion of the volume of the hot water storage tank 1. In the hot water filling of the bathtub 2 that does not necessarily require the hot water as much as in the upper part, the amount of tap water mixed from the pipe 23 in the first mixing valve 14 is reduced by positively using the hot water at the intermediate temperature. Thus, waste of heat energy can be suppressed, and high-temperature water necessary for the hot water supply heat exchanger 4 can be efficiently used.
Thus, by actively using intermediate water at an intermediate temperature, it is possible to efficiently use high-temperature water necessary for the hot water supply heat exchanger 4 and the reheating heat exchanger 24.

  Also in the second embodiment, the bathtub 2 passes through the pipe 25 downstream of the branch point 30 of the pipe 29b, the circulation mixing valve 31 and the downstream pipe 3 of the outlet pipe 26 of the reheating pipe. Since the hot water is filled with two pipes and the hot water is filled with a constant water pressure via the pressure reducing valve 6, the hot water filling time can be shortened.

Further, the temperature detection signal of the hot water detected by the top temperature sensor 47 of the hot water storage tank 1 and the temperature detection of the hot water detected by the temperature sensor 49 arranged in the middle of the volume of the hot water storage tank 1 in the vertical direction. A signal is input to the controller 16, and the controller 16 predicts the temperature of hot water flowing out from the second mixing valve 11 from these two temperatures and the like, and determines and controls the valve opening degree of the second mixing valve 11. . In addition, as a middle part in the vertical direction of the volume of the hot water storage tank 1, a position of about 2/5 to 3/5 from above the volume of the hot water storage tank 1 is preferable.
Thereby, the member for detecting the mixing temperature downstream of the second mixing valve 11 can be eliminated, the system becomes easy, and the production cost can be reduced.

In the first embodiment and the second embodiment, the case where the hot water filling time is shortened by using the piping used for reheating is described as an example. It can also be used to fill with water. Moreover, although the piping which fills up the bathtub 2 illustrated the case of two piping used for reheating, if it is plurality, the number will not be limited.
As mentioned above, although the electric water heater of this invention was demonstrated based on 1st Embodiment, 2nd Embodiment, this invention is not limited to the structure described in 1st Embodiment, 2nd Embodiment. The configuration can be changed as appropriate without departing from the spirit of the invention.

It is a lineblock diagram showing an example of an electric water heater concerning a 1st embodiment of the present invention. It is a circuit diagram which shows the hot water supply operation of the electric water heater of 1st Embodiment with a thick line. It is a circuit diagram which shows the hot water filling circuit of the electric water heater of 1st Embodiment with a thick line. It is a circuit diagram which shows the circuit of the reheating of the electric water heater of 1st Embodiment with a thick line. It is the block diagram which showed the circuit at the time of hot water filling with the thick line in the example of the electric water heater concerning 2nd Embodiment.

Explanation of symbols

1 Hot water storage tank 2 Bathtub 2i Bathing retreat entrance (circulation circuit for reheating)
2o Bathing retreat exit (circulation circuit for reheating)
3 Piping (hot water circuit, recirculation circuit)
4 Heat exchanger for hot water supply 6 Pressure reducing valve (water filling circuit)
7 Piping (hot water supply circuit, hot water filling circuit)
8 Heat pump unit (heat pump part)
9 Piping (Water-filled circuit of claim 2)
10 First outlet (circulation circuit for heating, filling circuit)
11 Second mixing valve 12 Second outlet 13 Pipe (hot water filling circuit of claim 2)
14 First mixing valve 18 Hot water circulation pump 19 Mixing tap (hot water supply location)
22 Water pipe (hot water supply circuit, hot water filling circuit)
23 Piping (Water-filled circuit)
24 Heat exchanger for reheating 25 Piping (water filling circuit, circulation circuit for reheating)
26 Piping (circulation circuit for reheating)
27 Pump (water filling circuit, recirculation circuit for reheating)
28 Solenoid valve (water filling circuit)
29a Piping (hot water filling circuit, circulation circuit for reheating)
29b Piping (water filling circuit)
30 branch point (water filling circuit, recirculation circuit for reheating)
31 Circulating and mixing valve (water filling circuit, recirculation circuit for reheating)
36 Piping (Hot water supply circuit)
37 Hot water temperature sensor (hot water supply circuit)
38 Hot water flow rate sensor (Hot water supply circuit)
39 Accumulator (Hot Water Supply Circuit)
40 Piping (Hot water supply circuit)
41 Piping (circulation circuit for heating, filling circuit)
42 Piping (circulation circuit for heating)
43 Check valve (circulation circuit for heating)
44 Check valve (circulation circuit for heating)
47 Tank top temperature sensor (first temperature sensor)
49 Temperature sensor (second temperature sensor)
53 Water temperature sensor (Hot water supply circuit)
54 Piping (water filling circuit)
55 bath flow sensor (water filling circuit)
56 Temperature sensor (4th temperature sensor)
57 Water level sensor (circulation circuit for reheating)
58 Piping (circulation circuit for reheating)
59 Temperature sensor (third temperature sensor)
2P rebirth circuit (circulation circuit for rebirth)
2S water heater (electric water heater)
2Y hot water filling circuit S water heater (electric water heater)

Claims (7)

A hot water heater that uses hot water stored in the hot water storage tank by heating tap water introduced into the hot water storage tank through a pressure reducing valve in a heat pump unit,
The hot water taken out from the first outlet disposed at the upper part of the hot water storage tank is led out by a hot water circulation pump, and heat is exchanged through the primary side of the hot water heat exchanger to lower the temperature of the hot water at the lower part of the hot water storage tank. A heating circuit to be returned to
Tap water is introduced into the secondary side of the hot water heat exchanger, the hot water supply heat exchanger is heated to a predetermined set temperature by the hot water passing through the primary side, and supplied to the hot water supply location;
A hot water filling circuit for supplying hot water, which is mixed with a predetermined set temperature by a first mixing valve, with hot water taken out from a first outlet of the hot water storage tank and tap water introduced through the pressure reducing valve;
Water in the bathtub or hot water is circulated in a reheating heat exchanger disposed in the upper part of the hot water storage tank, heat is indirectly exchanged with the hot water in the upper part of the hot water tank, and heated. A water heater comprising: a recirculation circuit for supplying the heated hot water to the bathtub. A second take-out port provided at a middle portion of the hot water storage tank in the vertical direction of the volume, and for deriving hot water in the hot water storage tank;
A second mixing valve that mixes the hot water taken out from the second outlet and the hot water taken out from the first outlet at the top of the hot water storage tank;
In the hot water filling circuit, hot water obtained by mixing hot water mixed by the second mixing valve and tap water introduced through the pressure reducing valve so as to have a predetermined set temperature by the first mixing valve is supplied to the bathtub. The hot water supply device according to claim 1, wherein the hot water supply device is supplied. Based on the temperature of the hot water detected by the first temperature sensor at the top of the hot water storage tank and the temperature of the hot water detected by the second temperature sensor disposed in the middle of the volume of the hot water storage tank in the vertical direction. Then, the valve opening degree of the second mixing valve is controlled so that the temperature of the hot water flowing out from the second mixing valve becomes a predetermined temperature. The hot water heater according to claim 2 or 3, wherein the intermediate portion is located at a position of about 2/5 to 3/5 from above in the vertical direction of the volume of the hot water storage tank. A temperature detected by a third temperature sensor of hot water flowing out from the heat exchanger for reheating disposed upstream of a circulation mixing valve for adjusting the flow rate of the recirculation circuit at the start of bath reheating, Based on the temperature detected by the fourth temperature sensor of the hot water heading from the inside of the bathtub toward the reheating heat exchanger, the circulation so that the temperature of the heated hot water returned to the bathtub becomes a predetermined temperature. The water heater according to any one of claims 1 to 4, wherein the opening degree of the mixing valve is controlled. The hot water supply circuit according to any one of claims 1 to 5, wherein the hot water filling circuit supplies the hot water to the bathtub using a plurality of pipes. The hot water supply apparatus according to claim 6, wherein the plurality of pipes are pipes respectively connected to a reheating entrance and a retreating outlet used for reheating in the bathtub.

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