JP2002267267A - Hot water supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce initial cost by an arrangement where a hot water supply apparatus having a capacity lower than a required one can be installed, while satisfying the hot water supply capacity required for the entire system. SOLUTION: The lowest temperature of hot water in a hot water storage tank 3, at which a maximum hot water supply quantity dependent on the hot water supply capacity required for the hot water supply system can be supplied with the hot water supply capacity of an installed hot water supply apparatus 6 is determined as a specified temperature. A controller 19 controls driving of a gas engine 1, such that to lowest temperature of hot water in the hot water storage tank 3 detected by a thermistor 41 is kept at the specified temperature, thus controlling heating through a heat exchanger 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply system for supplying hot water to a kitchen or a bath, and more particularly, to a hot water supply system having a hot water tank.

[0002]

2. Description of the Related Art Conventionally, in a hot water supply system combining a hot water storage tank and a water heater as an auxiliary heat source, if the temperature of the hot water in the hot water tank decreases and cools down, the amount of hot water that the system can supply is determined by the water heater It will depend on the hot water supply capacity.
Therefore, for example, when the hot water supply capacity of No. 24 is required for the entire system, it is necessary to install the No. 24 water heater.

[0003]

However, when the temperature of the hot water in the hot water tank is high, the hot water supply device hardly needs the hot water supply capacity, and the temperature of the hot water in the hot water tank is equal to the temperature of the general city water. Because the water temperature is often maintained at a higher temperature, it is very little to make the best use of the hot water supply capacity of the water heater. The installation is wasteful in terms of initial costs and is inefficient.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and provides a water heater having a capacity smaller than the required hot water supply capacity while satisfying the required hot water supply capacity as a whole system. The purpose is to reduce the initial cost as much as possible.

[0005]

In order to achieve the above-mentioned object, the present invention is configured as follows.

That is, a hot water supply system according to a first aspect of the present invention is a hot water supply system for storing hot water heated by heating means in a hot water storage tank and supplying the hot water from the hot water storage tank via an auxiliary heat source. Temperature detecting means for detecting the temperature of the hot water in the hot water tank, and controlling the heating by the heating means based on the output of the temperature detecting means to maintain the minimum temperature of the hot water in the hot water tank at a predetermined temperature. Holding means, wherein the predetermined temperature is determined based on a hot water supply capacity of the auxiliary heat source and a required hot water supply capacity required for the hot water supply system.

According to the first aspect of the present invention, the maximum amount of hot water determined by the required hot water supply capacity required for the hot water supply system is determined by the hot water supply capacity of the installed auxiliary heat source. The minimum temperature is determined as a predetermined temperature, and the holding unit controls the heating by the heating unit so as to maintain the minimum temperature of the hot water in the hot water tank detected by the temperature detection unit at the predetermined temperature. Regardless of the hot water supply capacity, the required hot water supply capacity can be satisfied as the hot water supply system, and an auxiliary heat source having a smaller hot water supply capacity than the conventional example can be used.

According to a second aspect of the present invention, in the first aspect of the present invention, an input unit is provided for setting and inputting the predetermined temperature.

According to the second aspect of the present invention, a predetermined temperature is determined in advance for each combination of various hot water supply capacities of the required hot water supply capacity of the hot water supply system and the hot water supply capacity of the auxiliary heat source. If a predetermined temperature corresponding to the actual combination of the hot water supply capacity of the auxiliary heat source and the required hot water supply capacity of the hot water supply system is set and input from the input unit,
The holding means holds the minimum temperature of the hot water in the hot water tank at the input predetermined temperature.

[0010] According to a third aspect of the present invention, in the first aspect of the present invention, the holding means is configured to determine, based on hot water supply capacity of the auxiliary heat source and required hot water supply capacity of the hot water supply system.
A calculating unit for calculating and calculating the predetermined temperature;

According to the third aspect of the present invention, the holding means automatically calculates the predetermined temperature based on the required hot water supply capacity required for the hot water supply system and the hot water supply capacity of the installed auxiliary heat source. The calculated minimum temperature of the hot water in the hot water storage tank can be maintained at the predetermined temperature, and the predetermined temperature is obtained in advance for various combinations of the required hot water supply capacity of the hot water supply system and the hot water supply capacity of the auxiliary heat source. No need.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the holding means performs the holding operation for holding the predetermined temperature only in a time zone in which the holding operation is expected to be necessary. Is what you do.

According to the present invention, the minimum temperature of the hot water in the hot water storage tank is maintained at the predetermined temperature only during the time period when it is predicted that the predetermined temperature needs to be maintained. The heat radiation loss can be reduced as compared with the case where the temperature is kept.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects of the present invention, the heating means includes a heat exchanger installed in the hot water storage tank. The heat medium heated by the exhaust heat of the heat source circulates.

According to the fifth aspect of the present invention, hot water can be stored in the hot water storage tank by effectively using the exhaust heat of the heat source.

According to a sixth aspect of the present invention, in the invention of the fifth aspect, the heat source is an internal combustion engine having a power generation function.

According to the present invention, the hot water can be stored in the hot water storage tank by effectively utilizing the exhaust heat of the internal combustion engine such as a gas engine, and the electric power generated by the internal combustion engine can be stored in, for example, a home. It can be supplied to an electric heater or the like for heating the internal load or hot water in the hot water storage tank, so that the energy can be effectively used.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below based on embodiments shown in the drawings.

(Embodiment 1) FIG. 1 is a schematic configuration diagram of a hot water supply system according to one embodiment of the present invention.

In this embodiment, electric power generated by a gas engine 1 as an internal combustion engine having a power generating function is supplied to a domestic load and an electric heater 40 of a general household in which the hot water supply system is installed. And a gas engine cogeneration system for recovering exhaust heat from the gas engine 1 and supplying hot water.

In FIG. 1, reference numeral 2 denotes an exhaust heat recovery circuit for circulating exhaust heat from the gas engine 1, for example, water cooling of the gas engine and heat medium such as antifreeze heated by exhaust gas of the gas engine. A heat exchanger 4 and a circulating pump 5 are provided inside 3.

A water supply pipe 7 is provided at a lower water supply port of the hot water storage tank 3.
On the other hand, a hot water outlet pipe is connected to an upper hot water outlet, and hot water from the hot water storage tank 3 is mixed with water supplied from the water supply pipe 7 by a mixing valve 9 to provide a water heater as an auxiliary heat source. It is configured so that hot water is supplied through the hot water 6.

In this system, the gas engine 1 is driven and the circulation pump 5 of the exhaust heat recovery circuit 2 is driven to transfer the heat medium from the gas engine 1 through the heat exchanger 4 as shown by the arrow. The exhaust heat recovered from the gas engine 1 is circulated through the heat exchanger 4 as a heating means.
And heats the low-temperature water in the hot water storage tank 3 and heats it by the electric heater 40 to store the heat. The hot water stored in the hot water storage tank 3 is supplied to the mixing valve 9 and the hot water supply as necessary. While hot water is supplied through the water heater 6, water is supplied to the hot water storage tank 3 from the water supply pipe 7.

The hot water supply 6 has a hot water supply heat exchanger 10 inside, and when the temperature of hot water from the hot water storage tank 3 is low, the hot water from the mixing valve 9 is heated to the set hot water supply temperature. Hot water.

Reference numeral 19 denotes a thermistor 41 installed in the hot water storage tank 3 and outputs of various sensors (not shown) and the remote controller 18.
The controller is a controller that controls driving stop of the gas engine 1 and controls each unit according to a setting operation from.

Conventionally, as described above, when the temperature of the hot water in the hot water storage tank 3 decreases, the amount of hot water that can be supplied by the hot water supply system depends on the hot water supply capacity of the water heater 6. Assuming that the required hot water supply capacity required for the supply system is, for example, No. 24, a water heater having the hot water supply capacity of No. 24 is installed as the water heater, and therefore, the cost efficiency is low. .

Therefore, the present embodiment is configured as follows so that a water heater with a small hot water supply capacity can be used while satisfying the hot water supply capacity required for the hot water supply system.

Conventionally, the required hot water supply capacity of the hot water supply system can be covered only by the hot water supply capacity of the water heater. In this embodiment, the required hot water supply capacity of the hot water supply system is required. The capacity is covered by the entire system including the water heater 6 and the hot water storage tank 3 in which hot water is stored by exhaust heat.

That is, since the hot water supply capacity of the hot water supply 6 is made smaller than that of the conventional one, the temperature of incoming water supplied to the hot water supply 6 is kept high. Therefore, the heating of the hot water in the hot water storage tank 3 is controlled. To keep the minimum temperature of the hot water high.

Here, if the water temperature of the water heater having the same water supply capacity as the required water supply capacity is set to 15 ° C., in order to satisfy the required water supply capacity with the water heaters having different water supply capacities, It is necessary to set the temperature of the incoming water, that is, the maximum amount of hot water determined by the required hot water supply capacity, the result of finding the incoming water temperature of the hot water supply that can be supplied even with the hot water supply capacity of the installed water heater, Is shown in Table 1.

[0031]

[Table 1] As shown in Table 1, the required hot water supply capacity is 20
The hot water supply capacity of the installed hot water heater is 1
In the case of No. 6, if the incoming water temperature is set to 20 ° C., the required hot water supply capacity can be satisfied.

When the required hot water supply capacity is No. 24 and the installed hot water supply capacity is No. 16, if the incoming water temperature is 23 ° C., the required hot water supply capacity is In the case where the installed water heater has a hot water supply capacity of No. 20, the required hot water supply capacity can be satisfied by setting the incoming water temperature at 19 ° C.

Therefore, in this embodiment, when the hot water supply 6 is installed and constructed to form a hot water supply system, the hot water supply capacity of the installed hot water supply 6 is set to, for example, by an input operation of the remote controller 18 as an input unit. , The controller 19 determines the required hot water supply capacity of the hot water supply system and the hot water supply capacity of
The input water temperature as shown in Table 1 above is calculated and calculated, and the calculated input water temperature is set as a predetermined temperature so that the minimum temperature of the hot water in the hot water storage tank 3 is maintained at the predetermined temperature.
The driving of the gas engine 1 is controlled to control the heating by the heat exchanger 4. The required hot water supply capacity is, for example,
The calculation may be performed based on the desired hot water temperature and the desired hot water amount, may be set in advance, or may be input from the remote controller 18.

The controller 19 determines the minimum temperature of the hot water in the hot water tank 3 based on the output of a thermistor 41 installed in the hot water tank 3 and detecting the temperature of the hot water in the hot water tank 3. The driving of the gas engine 1 is controlled so as to maintain the calculated predetermined temperature.

The gas engine 1 is normally driven such that high-temperature water is stored in the hot water tank 3 by the evening when hot water is most needed, such as bathing in a bath. In the embodiment, when the temperature of the hot water in the hot water tank 3 is detected to be low by the thermistor 41, the gas engine 1 is driven by the controller 19 and the hot water tank 3
Is maintained at the predetermined temperature.

As described above, since hot water having a predetermined temperature or higher is always stored in the hot water storage tank 3, hot water can be supplied at any time with the maximum hot water supply capacity required for the system.

As a result, the hot water supply system 6 can satisfy the required hot water supply capacity, and the hot water supply 6 having a smaller capacity than the required hot water supply capacity can be installed. The range of possible hot water heaters can be expanded, and the initial cost can be reduced as compared with the conventional example.

In the above-described embodiment, the hot water supply capacity of the hot water heater 6 to be installed is set and input from the remote controller 18, and the controller 19 adjusts the input hot water supply capacity and the required hot water supply capacity required for the hot water supply system. Although the predetermined temperature is calculated and calculated based on this, as another embodiment of the present invention, for example, the hot water supply capacity required for the system as shown in Table 1 and the hot water supply capacity of the water heater are described. For each of the various combinations, a predetermined temperature is previously obtained and a table is created. When the hot water supply 6 is installed and constructed to configure the hot water supply system, the corresponding predetermined temperature is selected from the table and the remote controller 18 is selected. Alternatively, the setting may be input.

In the above embodiment, the hot water supply capacity of the installed hot water heater 6 is set and input from the remote controller 18, but as another embodiment of the present invention, the installed hot water heater and the controller 19 , The controller 19 may automatically recognize the hot water supply capacity of the water heater using a model recognition signal or the like, and calculate and calculate the predetermined temperature based on the recognition.

In the above embodiment, the controller 19
Performs a holding operation for controlling the driving of the gas engine 1 so that hot water at a predetermined temperature or higher is always stored. However, as another embodiment of the present invention, hot water at a predetermined temperature or higher is constantly stored. Instead, the hot water may be stored only during the time zone that is expected to be necessary. The time zone predicted to be necessary may be, for example, monitoring and learning a daily hot water usage time zone, and the time zone may be determined based thereon, or the user himself / herself thinks that the hot water needs to be supplied. The time zone may be manually set and input.

As described above, by keeping the minimum temperature of the hot water in the hot water storage tank 3 at the predetermined temperature only during the time period when it is predicted that it is necessary to maintain the predetermined temperature, it is possible to maintain the minimum temperature at all times. Heat radiation loss can be reduced in comparison.

(Embodiment 2) FIG. 2 is a schematic configuration diagram of a hot water supply system according to another embodiment of the present invention, in which parts corresponding to those in Embodiment 1 described above have the same reference numerals. Attach.

The water heater ₆₁ of this embodiment is provided with a form 1 similarly to the hot water supply heat exchanger 10 of the embodiment described above, furthermore, the bath heat exchanger 14 Oyopi bath pump 15
In addition to hot water supply, bath filling and reheating are performed as described later.

[0044] Also in this embodiment, as in the first embodiment described above, the remote controller 18 ₁ of the operation, by inputting the installed Water Heater 6 ₁ of hot water supply capacity such as, controller 19 _1, the hot water supply based on the required demand hot water supply ability and water heater 6 ₁ of hot water supply capacity to the system, the incoming water temperature is calculated is calculated, the calculated incoming water temperature, as the predetermined temperature, the hot water of the lowest temperature in the hot water tank 3, The driving of the gas engine 1 is controlled so as to maintain the predetermined temperature.

Further, in this embodiment, the heat medium heated by the exhaust heat of the gas engine 1 is supplied to the gas engine 1
From the exhaust gas to the gas engine 1, in this example, the exhaust heat recovery circuit 2 is located downstream of the gas engine 1,
A second heat exchanger 12 is provided upstream of the heat exchanger 4.

The second heat exchanger 12 is connected to the heat exchanger 1
2 communicates with the circulation heating circuit 13 which bath water circulates for exchanging heat between the heat medium in this circulating heating circuit 13, the bath heat exchanger 14 of the water heater 6 in _1, bath pump 15
And the bathtub 11 and the circulation heating circuit 13
Is connected to a hot water supply pipe 17 via a pouring solenoid valve 16.

In this embodiment, hot water stored in hot water storage tank 3 is not poured into bath tub 11, but is first heated by hot water supply heat exchanger 10 from hot water supply pipe 17 via hot water supply electromagnetic valve 16. The water is supplied to the bathtub 11 without water. Then, the water in the tub 11 in a bath pump 15 of the water heater 6 _1, while circulating as shown by the arrow marks, to drive the gas engine 1, the heat transfer medium by driving the circulating pump 5 circulates By doing so, the heat medium heated by the exhaust heat of the gas engine 1 and the bathtub water are exchanged in the second heat exchanger 12 to heat the bathtub water, and to heat and reheat the bath. is there.

The example, in the case of increasing burning the bath, and instructs boilup by the remote control 18 _1, by the above-described control of the controller 19 ₁ of water set water level in the bathtub 11 is stretched, the bath water heater 6 ₁ The pump 15 is driven to circulate the bath water, while the gas engine 1 and the circulation pump 5 are driven to circulate the heat medium heated by the exhaust heat of the gas engine 1 and the bath heat is circulated by the second heat exchanger 12. Is heated to a set temperature.

The bath heat exchanger 14 may be used together with the heating by the second heat exchanger 12 as appropriate, or may be heated independently.

Thus, without going through the hot water storage tank 3,
The heat of the heat medium heated by the exhaust heat of the gas engine 1 is
Since it is used directly for heating and reheating of the bath by the second heat exchanger 12, after once storing heat in the hot water storage tank 3,
Efficiency can be increased as compared with the conventional example in which hot water is poured into a bathtub.

Conventionally, as described above, the hot water is poured into the bath after it is temporarily stored in the hot water storage tank 3, so that the hot water storage tank 3 needs to be large enough to store the amount of heat required for pouring the bath. Met.

On the other hand, in this embodiment, since the hot water in the hot water storage tank 3 is not used for pouring the bath, it is not necessary to store the amount of heat required for the hot water in the bath in the hot water storage tank 3. For example, the hot water storage tank 3 can be reduced in size to about 100 liters.

In this embodiment, an electric heater 40 for heating hot water in hot water storage tank 3 with electricity generated by gas engine 1 may be provided as in the first embodiment.

Other configurations and effects are the same as those of the first embodiment.

(Embodiment 3) FIG. 3 is a schematic configuration diagram of a hot water supply system according to still another embodiment of the present invention. Assign a sign.

[0056] water heater 6 ₂ of this embodiment is provided with a hot water supply heat exchanger 10 as in the first embodiment described above, furthermore, the heating heat exchanger 20 and the heating pump 21
And performs hot water heating in addition to hot water supply.

[0057] Also in this embodiment, as in the first embodiment described above, by operating the remote controller 18 _2, by inputting installed Water Heater 6 ₂ hot water supply capacity such as, the controller 19 _2, hot water supply based on the required demand hot water supply ability and water heater 6 ₂ of the hot water supply capacity to the system, the incoming water temperature is calculated is calculated, the calculated incoming water temperature, as the predetermined temperature, the hot water of the lowest temperature in the hot water tank 3, The driving of the gas engine 1 is controlled so as to maintain the predetermined temperature.

[0058] Further, in this embodiment, the second heat exchanger 12 provided in the exhaust heat recovery circuit 2 is communicated with a circulating heating circuit 13 ₁ heating hot water is circulated, the circulation heating circuit 13 _1, a heating heat exchanger 20 in the water heater 6 _2, and heating pump 21, which connects the heating terminal 22, such as a fan convector or floor heating.

In this embodiment, the controller 19 ₂
Under the control of, while driving the heating pump 21 in the water heater 6 ₂ circulating hot water for heating, circulating heating medium which is heated by driving the gas engine 1 and the circulation pump 5 by exhaust heat of the gas engine 1 Then, the heating water is heated by the second heat exchanger 12 to perform heating.

The heating heat exchanger 20 may be used in combination with the heating by the second heat exchanger 12 as appropriate, or may be independently heated.

Other structures and effects are the same as those of the first embodiment.

(Other Embodiments) In each of the above embodiments, the exhaust heat of the gas engine was recovered. However, as another embodiment of the present invention, the exhaust heat of another generator such as a fuel cell is used. May be collected.

Further, the present invention may have a configuration in which a hot water heating system as in Embodiment 3 is provided in addition to a hot water supply system having hot water filling and reheating functions as in Embodiment 2 described above.

In each of the embodiments described above, the case where the present invention is applied to a gas engine has been described. However, the present invention is not limited to a gas engine, but is applicable to an internal combustion engine using a liquid fuel such as a gasoline engine. Applicable.

[0065]

As described above, according to the present invention, the maximum amount of hot water determined by the required hot water supply capacity required for the hot water supply system can be adjusted by the hot water supply capacity of the installed auxiliary heat source. Is determined as a predetermined temperature, and the minimum temperature of hot water in the hot water storage tank is maintained at the predetermined temperature. Therefore, regardless of the hot water supply capacity of the auxiliary heat source, the required hot water The capacity can be satisfied, an auxiliary heat source having a smaller hot water supply capacity can be used as compared with the conventional example, and initial costs can be reduced and cost efficiency can be improved.

Further, according to the present invention, the minimum temperature of the hot water in the hot water tank is maintained at the predetermined temperature only during the time period when it is predicted that it is necessary to maintain the predetermined temperature. The heat loss can be reduced as compared with the case.

Further, according to the present invention, the exhaust heat of the internal combustion engine such as a gas engine can be recovered and hot water can be stored in the hot water storage tank.
It can be supplied to an electric heater or the like for heating loads in the home or hot water in a hot water storage tank, so that energy can be effectively used.

[Brief description of the drawings]

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

FIG. 2 is a schematic configuration diagram of a hot water supply system according to Embodiment 2 of the present invention.

FIG. 3 is a schematic configuration diagram of a hot water supply system according to a third embodiment of the present invention.

[Explanation of symbols]

1 Gas engine 2 exhaust heat recovery circuit 3 hot water tank 4 heat exchanger 5 circulation pump 6,6 _1, 6 ₂ water heater 11 bathtub 12 second heat exchanger 22 heating terminal 19 _1, 19 ₂ controller

 ──────────────────────────────────────────────────続 き Continued on the front page (71) Applicant 000221834 Toho Gas Co., Ltd. 19-18 Sakuradacho, Atsuta-ku, Nagoya-shi, Aichi (71) Applicant 000196680 Seibu Gas Co., Ltd. 1-17-1 Chiyo, Hakata-ku, Fukuoka-shi, Fukuoka No. 1 (72) Inventor Tatsuro Arai 93 Edocho, Chuo-ku, Kobe City, Hyogo Prefecture Inside Noritz Co., Ltd. (72) Inventor Toshizo Okada 93 Edocho, Chuo-ku, Kobe City, Hyogo Prefecture Noritsu Co., Ltd. (72) Inventor Takuji Saeki 93 Edo-cho, Chuo-ku, Kobe City, Hyogo Prefecture Inside Noritz Co., Ltd. (72) Inventor Isao Suzuki 1-5-20 Kaigan, Minato-ku, Tokyo Inside Tokyo Gas Co., Ltd. (72) Inventor Tanogashira Kenichi Kazuya Yamaguchi, Tokyo Gas Co., Ltd. (72) Inventor Kazuya Yamaguchi, Tokyo Gas Co., Ltd. ) Inventor Yoshitaka Kayahara, Osaka Gas Co., Ltd., 4-1-2 Hirano-cho, Chuo-ku, Osaka-shi, Osaka (72) Inventor Shin Iwata 4-1-2, Hirano-cho, Chuo-ku, Osaka, Osaka, Japan (72) Inventor Keiji Takimoto 4-1-2 Hirano-cho, Chuo-ku, Osaka-shi, Osaka Inside Osaka Gas Co., Ltd. (72) Inventor Tadao Sugawara 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka Co., Ltd. (72) Inventor Hiroshi Takagi 19-18, Sakuradacho, Atsuta-ku, Nagoya City, Aichi Prefecture Inside Toho Gas Co., Ltd. (72) Inventor Kazuhiro Matsumoto 1-17-11, Chiyo, Hakata-ku, Fukuoka, Fukuoka Prefecture Inside the corporation

Claims (6)

[Claims] 1. A hot water supply system for storing hot water heated by a heating means in a hot water tank and supplying hot water from the hot water tank via an auxiliary heat source, wherein a temperature detection for detecting a temperature of the hot water in the hot water tank. Means, and holding means for controlling the heating by the heating means based on the output of the temperature detecting means to maintain the minimum temperature of the hot water in the hot water storage tank at a predetermined temperature. Based on the hot water supply capacity of the heat source and the required hot water supply capacity required for the hot water supply system,
A hot water supply system characterized by being determined. 2. The hot water supply system according to claim 1, further comprising an input unit for setting and inputting the predetermined temperature. 3. The hot water supply system according to claim 1, wherein the holding unit includes a calculation unit that calculates the predetermined temperature based on a hot water supply capacity of the auxiliary heat source and a required hot water supply capacity of the hot water supply system. A hot water supply system, characterized in that: 4. The hot water supply system according to claim 1, wherein the holding unit performs the holding operation of holding the predetermined temperature only during a time period in which the holding operation is predicted to be necessary. Characterized hot water supply system. 5. The hot water supply system according to claim 1, wherein the heating means includes a heat exchanger installed in the hot water tank, and the heat exchanger includes a heat source. A hot water supply system, wherein a heat medium heated by heat circulates. 6. The hot water supply system according to claim 5, wherein the heat source is an internal combustion engine having a power generation function.