JP2003254610A - Hot water supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hot water supply system preventing delivery of dangerous high-temperature hot water even if a hot water connecting unit cannot control the burning, etc., of a burner of a water heater. <P>SOLUTION: In this hot water supply system, a solar water heater 10 and the water heater 30 are connected via the hot water supply connecting unit 20. A main channel comprising a hot water pipe 23 connecting the hot water connecting unit 20 to the water heater 30 and a hot water pipe 31 connected to the water heater is formed with a bypass channel by connecting a bypass pipe 32 for bypassing the water heater 30. An electric three-way valve 33 automatically changing over the channel according to the control operation of the hot water connecting unit 20 is installed in a junction of the bypass channel in the main channel. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention stores hot water generated by an auxiliary heat source such as solar heat in a heat storage tank,
The present invention relates to a hot water supply system in which hot water is delivered to a water heater via a hot water supply connection unit that can be mixed with tap water.

[0002]

2. Description of the Related Art As a hot water supply system using an auxiliary heat source, for example, a hot water supply system combining a solar water heater and a water heater that uses the heat of the sun to generate hot water has hitherto been used. Is commonly known.

In such a hot water supply system, a solar water heater and a water heater having a heat storage tank for storing hot water generated by utilizing solar heat are connected through a hot water supply connection unit, At the time of hot water supply, the hot water stored in the heat storage tank of the solar water heater is sent to the water heater via the hot water supply connection unit, but the hot water connection unit simply sends the hot water stored in the heat storage tank to the water heater. If necessary, the hot water sent from the heat storage tank is fully opened so that the hot water sent from the heat storage tank can be sent to the water heater in a state where clean water is mixed with the hot water. It is equipped with a mixing control valve that sends only water to the water heater, and sends only clean water to the water heater when fully closed.

Therefore, when hot water having a temperature higher than the hot water supply set temperature set for the water heater is stored in the heat storage tank, the mixing control valve of the hot water supply connection unit has a temperature higher than the hot water supply set temperature sent from the heat storage tank. By appropriately mixing hot water and tap water, hot water set temperature control that generates hot water at the hot water supply set temperature that is the target temperature is performed, and the hot water at the hot water supply set temperature generated by the hot water supply connection unit is sent to the water heater. Will be.

On the other hand, when hot water having a temperature higher than the hot water supply set temperature is not stored in the heat storage tank, the mixing control valve of the hot water supply connection unit appropriately mixes the hot water below the hot water supply set temperature sent from the heat storage tank with the clean water. By doing so, a fixed temperature control is performed in which the temperature is forcibly lowered to a predetermined fixed temperature that is the target temperature and is sent to the water heater, and hot water of the hot water set temperature is generated by burning the burner of the water heater. Will be done.

By the way, as described above, there is provided a hot water supply connection unit for selectively performing either one of the hot water supply set temperature control and the fixed temperature control based on the hot water supply set temperature and the temperature of the hot water sent from the heat storage tank. In the hot water supply system used, when hot water of the hot water supply set temperature is delivered from the hot water supply connection unit, it is necessary to forcibly stop the combustion of the burner of the hot water supply unit. Must send a combustion stop command.

However, when the water heater and the hot water connection unit are combined so that a common signal recognizable between them cannot be communicated with each other, the hot water connection unit controls the combustion of the burner of the water heater. Therefore, in such a case, as shown in FIG. 4, a bypass flow path that bypasses the hot water supply device 53 is provided to the main flow path 54 through which the hot water sent from the hot water supply connection unit 52 is supplied through the hot water supply device 53. A hot water supply system has been conventionally used in which a three-way valve 56 that connects 55 to each other and that switches the flow path by a manual operation is installed at a branch portion or a merging portion of the bypass flow path 55 in the main flow path 54.

Therefore, in such a hot water supply system 50, when hot water having a temperature higher than the hot water supply set temperature is stored in the heat storage tank 51, the user manually switches the three-way valve 56 to the bypass flow passage 55 side, When hot water below the hot water supply set temperature is stored in 51, the user manually operates the three-way valve 56.
However, if the user makes a mistake in the switching operation, hot water at the hot water set temperature cannot be supplied, and in particular, hot water at the hot water set temperature or higher is stored in the heat storage tank 51. If the switching operation of the three-way valve is erroneous while the hot water is on, hot water having the hot water supply set temperature sent from the hot water supply connection unit 52 is heated by the hot water supply device 53, which causes dangerous hot water discharge.

Therefore, an object of the present invention is to provide a hot water supply system capable of preventing dangerous high temperature hot water discharge even when the hot water supply connection unit cannot control the combustion of the burner of the water heater. It is in.

[0010]

In order to solve the above-mentioned problems, the invention according to claim 1 provides a water heater as a main heat source, a heat storage tank for storing hot water generated by an auxiliary heat source, A hot water supply connection unit equipped with a mixing control valve that sends hot water of a target temperature to the water heater by mixing hot water as necessary with the hot water sent from the heat storage tank, and is sent from the hot water supply connection unit. A main flow path for supplying hot water through the water heater, a bypass flow path connected to the main flow path so as to bypass the water heater, and a branch portion of the bypass flow path in the main flow path, or A three-way valve installed in the confluence section is provided, and when hot water having a hot water supply set temperature or higher is delivered from the heat storage tank to the hot water supply connection unit, the three-way valve is switched to the bypass flow path side. At the same time, the hot water supply connection unit performs hot water set temperature control to generate hot water at the hot water supply set temperature by mixing clean water, and hot water below the hot water supply set temperature is delivered from the heat storage tank to the hot water supply connection unit. Then, the hot water supply system is configured such that the three-way valve is switched to the hot water supply side and the hot water supply connection unit performs fixed temperature control for generating hot water having a predetermined fixed temperature by mixing clean water. It is provided.

As described above, in this hot water supply system, when hot water having a temperature higher than the hot water supply set temperature is sent from the heat storage tank to the hot water supply connection unit, the hot water supply connection unit is operated with the three-way valve switched to the bypass flow passage side. If the hot water supply set temperature control is performed and hot water below the hot water supply set temperature is sent from the heat storage tank to the hot water supply connection unit, the hot water supply connection unit performs fixed temperature control with the three-way valve switched to the water heater side. Therefore, unlike the conventional hot water supply system in which the user manually switches the three-way valve, dangerous hot water discharge can be prevented.

Further, since the hot water supply temperature may temporarily fluctuate immediately after the switching operation of the flow passage and the control operation of the hot water supply connection unit by the three-way valve, the hot water supply system of the invention according to claim 2 is present. As described above, when hot water having a minimum operating flow rate or more is being sent from the hot water supply connection unit, it is preferable not to perform the flow path switching operation and the hot water supply connection unit control switching operation by the three-way valve. The effect that the hot water supply temperature does not fluctuate extremely and the user is unlikely to feel uncomfortable is obtained.

Further, as in the hot water supply system according to a third aspect of the present invention, a fixed operation mode in which the hot water supply connection unit forcibly performs the fixed temperature control with the three-way valve switched to the water heater side, Based on the hot water supply set temperature and the temperature of hot water delivered from the heat storage tank, the hot water supply set temperature control performed by the hot water supply connection unit with the three-way valve switched to the bypass flow path side or the three-way valve If the hot water supply unit is capable of switching between the normal operation mode in which either one of the fixed temperature control performed by the hot water supply connection unit is selectively performed in the state of being switched to the Since the hot water of is stored in the heat storage tank, in the normal operation mode, even in the summer when hot water is supplied almost through the bypass flow path,
By periodically switching to the fixed operation mode and performing the hot water supply operation, it is possible to discharge the water accumulated in the water heater portion of the main flow path, and thus it is possible to prevent the occurrence of dead water. .

Further, when a water heater having an automatic pouring function for the bathtub is installed, when attempting automatic pouring into the bathtub, hot water must be sent from the hot water connection unit to the water heater. Since hot water above the hot water supply set temperature is stored in the heat storage tank, there is a problem that in the normal operation mode, in the summer when hot water is mostly supplied through the bypass passage, it is impossible to perform automatic hot water pouring into the bathtub. is there. However, in the hot water supply system described above, it is possible to switch between the fixed operation mode and the normal operation mode. Therefore, by switching to the fixed operation mode, it is possible to use the automatic pouring function of the water heater. The effect of becoming

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments will be described below with reference to the drawings. FIG. 1 shows a water heater 30 as a main heat source.
1 shows a schematic configuration of a hot water supply system 1 in which a solar water heater 10 serving as an auxiliary heat source is combined. As shown in FIG. 1, the hot water supply system 1 includes a solar water heater 10 and a water heater 30 connected to each other via a hot water supply connection unit 20, and a hot water supply connection unit 20 and a hot water supply device 3
Hot water pipe 23 and water heater 3 for connecting to the hot water inlet side of 0
A bypass flow path is formed by connecting a bypass pipe 32 bypassing the water heater 30 to the main flow path consisting of the hot water supply pipe 31 connected to the hot water outlet side of 0. An electric three-way valve 33 that switches the flow path is installed in the branch portion.

The solar water heater 10 and the hot water supply connection unit 20 are housed in the same casing as the components surrounded by the one-dot chain line in FIG. 1, and the controller 30a of the water heater 30 has a water heater. An operation remote controller 30b installed in a kitchen or the like for operating the unit 30 is connected.

The solar water heater 10 comprises a solar heat collector 11 and a closed heat storage tank 15, and the heat storage tank 15 has a water supply pipe 1 for supplying clean water to the lower end thereof.
6 is connected to the hot water supply pipe 1 for sending hot water stored in the upper end to the hot water supply connection unit 20.
7 is connected.

In the solar heat collector 11, a circulation path for a heat medium is formed by a solar pipe 12 which connects the inlet side and the outlet side thereof.
Is a heat exchange part 12a partially introduced into the heat storage tank 15.
have. A circulation pump 13 for circulating a heat medium between the solar heat collector 11 and the heat exchanging unit 12a and a reserve tank 14 for storing the heat medium are connected to the solar pipe 12. The heat medium heated by is introduced into the heat storage tank 15 through the solar pipe 12 and exchanges heat with the water in the heat storage tank 15 in the heat exchange section 12a, whereby hot water is generated in the heat storage tank 15. It has become so.

In the reserve tank 14, there is installed a holding amount detecting means 14a for detecting whether or not the holding amount of the heat medium stored in the reserve tank 14 is below a required minimum amount. When the detection means 14a detects that the amount of the heat medium held is below the required minimum amount, the operation of the circulation pump 13 is forcibly stopped in order to prevent the idle operation of the circulation pump 13. There is.

Further, in the solar water heater 10, a temperature detection signal from a heat collection temperature sensor (not shown) installed in the solar heat collector 11, a temperature of hot water stored in the heat storage tank 15 (hereinafter, referred to as tank temperature). The temperature detection signal from the tank temperature sensor 18 for detecting Tt, and the possession amount detection means 14
The controller 10a to which the holding amount detection signal from a, the flow rate detection signal from the flow rate sensor 19 installed on the upstream side of the water supply pipe 16, and the like are respectively installed is mounted. The start / stop control of the circulation pump 13 is independently performed based on the temperature detection signal from the heat collecting temperature sensor.

An operation remote controller 10b having an operation switch is connected to the controller 10a, and the hot water supply set temperature Te on the hot water supply connection unit 20 side can be set by the operation remote controller 10b. There is.

As shown in the figure, the hot water supply connection unit 20 supplies clean water supplied via a water supply pipe 22 and hot water supplied from the heat storage tank 15 via a hot water supply pipe 17.
A mixing control valve 21 that mixes as needed is provided, and the hot water sent from the heat storage tank 15 is connected to the outlet side of the mixing control valve 21 as it is or in a state where it is appropriately mixed with tap water. It is designed to be delivered to the hot water supply device 30 side through a hot water pipe 23 forming a passage. In addition, the mixing control valve 21 is in a fully opened state, and from the heat storage tank 15 to the hot water supply pipe 17.
Only the hot water supplied via the water is sent to the water heater 30 side,
On the contrary, in the fully closed state, only the clean water supplied via the water supply pipe 22 is sent to the water heater 30 side.

Further, the hot water supply connection unit 20 interconnects a water supply pipe 22 connected to the upper water inlet side of the mixing control valve 21 and a hot water pipe 23 connected to the hot water outlet side of the mixing control valve 21. A bypass pipe 24 is provided, and the bypass pipe 24 is provided with a diaphragm-type solenoid valve 25 that shuts off the flow path of the bypass pipe 24 in an energized state.

The hot water supply pipe 17 and the hot water pipe 23 connected to the mixing control valve 21 have a hot water temperature for detecting the temperature (hereinafter referred to as hot water temperature) Ts of hot water sent from the heat storage tank 15. Sensor 26 and hot water supply connection unit 2
A hot water temperature sensor 27 for detecting the temperature (hereinafter referred to as hot water temperature) To of hot water delivered from 0 is installed.

The hot water supply connection unit 20 has a controller 20a which can communicate with the controller 10a of the solar water heater 10 through a serial interface.
The temperature detection signals from the hot water temperature sensor 26 and the hot water temperature sensor 27 are input to the controller 20a, and the hot water supply set temperature Te set by the operation remote controller 10b is transmitted from the controller 10a. These temperature detection signals and hot water supply set temperature Te
Based on the above, the controller 20a controls the mixing control valve 21.

The temperature of hot water sent from the heat storage tank 15, that is, the hot water temperature T detected by the hot water temperature sensor 26.
When s is equal to or higher than the hot water supply set temperature Te, hot water having the hot water supply set temperature Te can be supplied by appropriately mixing clean water without heating by the water heater 30, so that the electric three-way valve 33 is bypassed. The temperature of the hot water sent from the hot water supply connection unit 20 while switching to the road side, that is,
The hot water supply temperature control for controlling the mixing control valve 21 is performed so that the hot water supply temperature To detected by the hot water supply temperature sensor 27 becomes the hot water supply set temperature Te.

On the other hand, when the hot water supply temperature Ts is lower than the hot water supply set temperature Te, the hot water of the hot water supply set temperature Te cannot be supplied unless the water heater 30 heats it. , Electric three-way valve 3
By switching 3 to the water heater 30 side and burning the burner of the water heater 30, hot water of a fixed temperature (for example, 30 ° C.) Tf is generated so that hot water of the hot water set temperature Te can be reliably generated. The fixed temperature control for mixing the clean water is performed by adjusting the opening degree of the mixing control valve 21 so that the water is delivered.

In the hot water supply system 1, when the operation switch of the operation remote controller 10b is turned on,
The hot water supply connection unit 20 controls the hot water supply set temperature Te and the hot water supply temperature T.
The hot water supply operation is performed in the normal operation mode in which either the hot water supply set temperature control or the fixed temperature control is selectively performed based on s. However, when the operation switch of the operation remote controller 10b is turned off, the electric three-way operation is performed. The valve 33 is the water heater 30
The hot water supply connection unit 20 is switched to the fixed operation mode in which the fixed temperature control is forcibly performed.

The operation of the hot water supply system 1 will be described below with reference to the flow chart shown in FIG.
First, it is determined whether or not the operation switch of the operation remote controller 10b is turned on (step S1), and when the operation switch is turned on, that is, when the normal operation mode is set, then the flow sensor Based on the flow rate detection signal from 19, it is determined whether or not the hot water supply unit 20 is sending hot water at a minimum working flow rate or higher (step S2), and the hot water supply connection unit 20 is sending hot water at a minimum working flow rate or higher. If so, the process proceeds to step S1 without changing the current operating state.

On the other hand, in step S2, when the amount of hot water delivered from the hot water supply connection unit 20 is less than the minimum operating flow rate, based on the temperature detection signal from the in-tank temperature sensor 18, the inside of the heat storage tank 15 It is determined whether or not the temperature Tt is equal to or higher than the hot water supply set temperature Te (step S3), and if the in-tank temperature Tt is equal to or higher than the hot water supply set temperature Te, the hot water supply connection is made with the electric three-way valve 33 switched to the bypass flow passage side. The unit 20 controls the hot water supply temperature setting (step S
4) Go to step S1, but if the tank temperature Tt is lower than the hot water supply set temperature Te, the hot water supply connection unit 2 with the electric three-way valve 33 switched to the water heater 30 side.
0 performs fixed temperature control (step S5), and step S
Move to 1.

In step S1, the heat storage tank 1 is operated when the operation switch of the operation remote controller 10b is turned off, that is, when the fixed operation mode is set.
Regardless of whether the bath temperature Tt of 5 is equal to or higher than the hot water supply set temperature Te, the hot water supply connection unit 20 performs fixed temperature control with the electric three-way valve 33 forcedly switched to the hot water heater 30 side (step S6), the process proceeds to step S1.

As described above, in the hot water supply system 1,
When the hot water supply connection unit 20 performs the hot water supply set temperature control, the electric three-way valve 33 automatically switches to the bypass flow path side, and when the hot water supply connection unit 20 performs the fixed temperature control, the electric three-way valve 33 is the water heater 30 side. Since it automatically switches to a hot water supply, unlike the conventional hot water supply system where the user has to manually switch the three-way valve according to the temperature of the hot water stored in the heat storage tank Can be prevented.

When the pipe length from the heat storage tank 15 to the water heater 30 becomes long, the hot water supply temperature is temporarily set immediately after switching the flow path by the electric three-way valve 33 and switching the control in the hot water supply connection unit 20. The temperature Te may cause overshoot or undershoot, but in the hot water supply system 1, when hot water of a minimum operating flow rate or more is delivered from the hot water supply connection unit 20, the flow path by the electric three-way valve 33 is used. Since the switching operation of the above and the switching operation of the control of the hot water supply connection unit 20 are not performed, for example, the hot water temperature does not fluctuate extremely while the shower is being used, and the user feels uncomfortable. The effect of not giving is obtained.

Further, in this hot water supply system 1, the hot water supply connection unit 20 sets the hot water supply by turning on and off the operation switch of the operation remote controller 10b to switch the electric three-way valve 33 to the bypass flow passage side or the water heater side. Fixed operation in which the hot water supply connection unit 20 forcibly performs fixed temperature control in the normal operation mode in which either one of the temperature control and the fixed temperature control is selectively performed and the electric three-way valve 33 is switched to the water heater 30 side. Since the hot water having the hot water supply set temperature Te or higher is stored in the heat storage tank 15 since it is possible to switch between the modes, in the normal operation mode, in the summer when hot water is mostly supplied through the bypass passage. Also, the user switches to the fixed operation mode by periodically turning off the operation switch of the operation remote controller 10b. By performing the hot water supply operation state, it is possible to discharge the water remaining in the water heater 30 portion in the main passage, there is an effect that it is possible to prevent the occurrence of dead water.

When the water heater 30 has an automatic pouring function for the bathtub, if hot water is to be poured into the bathtub, hot water must be delivered from the hot water connection unit 20 to the water heater 30. Since hot water having a hot water supply set temperature Te or higher is stored in the heat storage tank 15, in the normal operation mode described above, automatic hot water pouring into the bathtub can be performed in the summer when hot water is mostly supplied through the bypass passage. There is a problem that you can not do it.

However, in this hot water supply system 1,
As described above, since it is possible to switch between the fixed operation mode and the normal operation mode, when the user turns off the operation switch of the operation remote controller 10b to switch to the fixed operation mode, a fixed temperature (for example, , 30
Since the warm water of (° C.) Tf can be reliably delivered to the water heater 30, automatic pouring into the bathtub using the automatic pouring function of the water heater 30 becomes possible.

In the embodiment described above, in the normal operation mode, when hot water is being supplied while the hot water supply connection unit 20 is performing the hot water supply temperature setting control, the operation switch of the operation remote controller 10b is turned off. And the switching to the fixed operation mode, the electric three-way valve 33
Since switching of the flow path and switching of the control of the hot water supply connection unit 20 are performed due to the possibility that the hot water supply temperature may fluctuate temporarily, for example, as in the flow chart shown in FIG. When the operation switch is turned off, the hot water supply connection unit 2
From 0, it is determined whether or not hot water of a minimum operating flow rate or more is being sent out, that is, whether or not hot water is being supplied (step S
7) When hot water is being supplied, the flow proceeds to step S1 without performing the flow path switching operation by the electric three-way valve 33 and the control switching operation of the hot water supply connection unit 20, and only when hot water is not being supplied, the process proceeds to step S8. It is desirable to perform the switching operation of the flow path by the electric three-way valve 33 and the switching operation of the control of the hot water supply connection unit 20 after the shift.

Further, in the above-described embodiment, the electric three-way valve 33 is installed at the branch portion of the bypass flow passage in the main flow passage, but the present invention is not limited to this, and the bypass flow passage in the main flow passage is not limited to this. It is also possible to install the electric three-way valve 33 in the confluence part.

The above-described embodiment is a hot water supply system using a solar water heater as an auxiliary heat source.
The auxiliary heat source in the hot water supply system is not limited to such a solar water heater, and various auxiliary heat sources such as a hot water supply system using waste heat of a gas engine or a gas turbine in a cogeneration system as an auxiliary heat source can be used. It goes without saying that the present invention can be applied to a hot water supply system using an auxiliary heat source.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a hot water supply system according to the present invention.

FIG. 2 is a flowchart showing an operating operation of the hot water supply system of the above.

FIG. 3 is a flowchart showing an operation operation of a hot water supply system according to another embodiment.

FIG. 4 is a schematic configuration diagram showing a conventional hot water supply system.

[Explanation of symbols]

1 Hot water supply system 10 Solar water heater 10a controller 10b Operation remote control 11 Solar heat collector 13 Circulation pump 15 heat storage tank 18 Tank temperature sensor 19 Flow rate sensor 20 Hot water supply connection unit 20a controller 21 Mixing control valve 23 Hot water piping (main flow path) 26 Hot water temperature sensor 27 Hot water temperature sensor 30 water heater 31 Hot water supply pipe (main flow path) 32 Bypass pipe (bypass flow path) 33 Electric three-way valve

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takayoshi Shimizu             93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Stock Association             Company Noritsu (72) Inventor Tetsuya Watanabe             93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Stock Association             Company Noritsu

Claims (3)

[Claims] 1. A water heater as a main heat source, a heat storage tank that stores hot water generated by an auxiliary heat source, and hot water sent from the heat storage tank is mixed with tap water as needed to obtain a target temperature. A hot water supply connection unit equipped with a mixing control valve for sending hot water to the water heater, a main flow path for supplying hot water sent from the hot water supply connection unit through the water heater, and a bypass for the water heater. A bypass flow passage connected to the main flow passage, and a three-way valve installed at a branch portion or a confluence portion of the bypass flow passage in the main flow passage, wherein hot water having a hot water supply set temperature or higher is supplied from the heat storage tank. When the water is delivered to the hot water supply connection unit, the three-way valve is switched to the bypass flow path side, and the hot water supply connection unit mixes clean water to control the temperature of the hot water supply set temperature. When hot water set temperature control for generating water is performed and hot water below the hot water set temperature is sent from the heat storage tank to the hot water supply connection unit, the three-way valve is switched to the water heater side, and the hot water supply connection unit is A hot water supply system that performs fixed temperature control to generate hot water having a predetermined fixed temperature by mixing clean water. 2. When the hot water supply unit supplies hot water of a minimum operating flow rate or more, the switching operation of the flow path by the three-way valve and the control operation of the hot water supply connection unit are not performed. The hot water supply system according to Item 1. 3. A fixed operation mode in which the hot water supply connection unit forcibly performs the fixed temperature control in a state where the three-way valve is switched to the hot water supply side, and the hot water supply set temperature and hot water sent from the heat storage tank. The hot water supply temperature control performed by the hot water supply connection unit in the state where the three-way valve is switched to the bypass flow path side, or the hot water supply connection unit performed in the state where the three-way valve is switched to the water heater side, based on The hot water supply system according to claim 1, wherein the hot water supply system is configured to be switchable between a normal operation mode in which either one of the fixed temperature control is selectively executed.