JP2002130825A - Hot water supply apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance convenience by making possible to use hot water even if the temperature of hot water in a hot water storage tank is lowered due to overuse thereof. SOLUTION: At the time of hot water supply, a thermistor 14 detects the inner temperature of a hot water storage tank 10. When the detected temperature is higher than a specified level, a decision is made that hot water has been stored sufficiently and hot water is supplied from the hot water outlet 5 of the hot water storage tank 10 through a hot water changeover valve 13 and a hot water supply line 6. When the detected temperature is lower than the specified level, a decision is made that the temperature of water in hot water storage tank 10 is too low and high temperature hot water from a heat source 1 is switched from a heating coil 2 to a passage circulating through a heat exchanger 11 and then low temperature supply water is heat exchanged with high temperature hot water through the heat exchanger 11 before being supplied through the hot water changeover valve 13 and the hot water supply line 6.

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 device for supplying hot water, and more particularly to a hot water supply device suitable for recovering waste heat and supplying hot water.

[0002]

2. Description of the Related Art As a conventional hot water supply device, for example, a so-called cogeneration system for supplying hot water using waste heat of a generator that generates waste heat such as an engine generator using a gas engine as a prime mover or a fuel cell. There is.

FIG. 3 is a schematic configuration diagram of a water heater of such a cogeneration system. In FIG. 3, reference numeral 1 denotes a heat source such as an engine generator, and 2 denotes high-temperature water heated by waste heat from the heat source 1. For example, a heating coil 10 for supplying high-temperature water heated by water cooling of a gas engine and waste gas of a gas engine is provided with the heating coil 2, and a water supply pipe 4 is provided at a lower water supply port 3. Hot water supply pipes 6 are connected to the hot water outlet 5 at the upper part, respectively. A bypass pipe 7 is provided between the water supply pipe 4 and the hot water supply pipe 6, a bypass flow rate control valve 8 is provided in the bypass pipe 7, and a hot water supply pipe 6 is provided in the hot water supply pipe 6. A flow control valve 9 is provided.

[0004] In the hot water storage tank 10, low-temperature water from the water supply pipe 4 is heated and stored by high-temperature water using waste heat, and the stored hot water is discharged from a hot water outlet above the hot water storage tank 10 as necessary. 5 is supplied through a hot water supply pipe 6, while low-temperature water is supplied from a water supply pipe 4 through a water supply port 3 below the hot water storage tank 10.

[0005]

In such a hot water supply apparatus, if the hot water stored in the hot water storage tank 10 is excessively used,
Since the amount of low-temperature water supplied from the lower water supply port 3 increases, the temperature of the hot water supplied from the water supply port 5 decreases, or the amount of water supplied exceeds the amount of hot water stored and hot water can be used. There is a disadvantage that it disappears.

[0006] The present invention has been made in view of the above points, and it is an object of the present invention to make it possible to use hot water even when the temperature of hot water in a hot water storage tank is reduced, thereby improving convenience.

[0007]

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

That is, the hot water supply apparatus of the present invention according to the first aspect of the present invention is a hot water supply tank for heating internal water supplied from a water supply pipe by high-temperature water heated by a heat source to store heat, and supplying water from the water supply pipe. A heat exchanger for heating the supplied water with the high-temperature water to supply hot water.

According to the first aspect of the present invention, when the hot water in the hot water tank is excessively used and the temperature of the hot water in the hot water tank decreases so that hot water cannot be supplied, the high-temperature water from the heat source is supplied to the heat exchanger. High-temperature hot water obtained by heat exchange can be used.

A hot water supply apparatus according to a second aspect of the present invention includes a hot water storage tank that heats internal water supplied from a water supply pipe by high-temperature water heated by a heat source to store heat, and a hot water supply pipe of the hot water storage tank. A heat exchanger for heating the supplied hot water with the high-temperature water to supply hot water.

According to the second aspect of the present invention, when the hot water in the hot water tank is excessively used and the temperature of the hot water in the hot water tank decreases so that hot water cannot be supplied, the high-temperature water from the heat source is supplied to the heat exchanger. High-temperature hot water obtained by heat exchange can be used, and moreover, by exchanging the hot water in the hot water storage tank with a heat exchanger, hot water can be obtained and supplied more efficiently.

According to a third aspect of the present invention, in the first or second aspect of the invention, the high-temperature water is heated by waste heat of the heat source, and the heat exchanger is a double-tube heat exchanger. It is a vessel.

According to the third aspect of the present invention, since the high-temperature water is heated by the waste heat of the heat source, the waste heat can be recovered and used effectively. When the hot water in the hot water storage tank is too low to supply hot water from the hot water storage tank, instantaneous hot water supply is possible with this double-pipe heat exchanger.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the circulation path of the high-temperature water is switched to a path circulating in the hot water storage tank or a path circulating in the heat exchanger. High-temperature water path switching means is provided.

According to the fourth aspect of the present invention, when storing heat, high-temperature water from a heat source is supplied to a route for circulating the hot-water tank, and when hot water in the hot-water tank is too low to supply hot water from the hot-water tank. By switching to a path circulating through the heat exchanger, the heat of the high-temperature water from the heat source can be used efficiently.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects of the present invention, there is provided a hot water supply path switching means for switching between hot water supply from the hot water storage tank and hot water supply from the heat exchanger. I have.

According to the present invention, when the heat is sufficiently stored, hot water is supplied from the hot water storage tank, and when the temperature of the hot water in the hot water storage tank is low and hot water cannot be supplied from the hot water storage tank, the heat exchanger is used. You will be able to supply hot water.

According to a sixth aspect of the present invention, in accordance with the fifth aspect of the present invention, there is provided a temperature detecting means for detecting a temperature of the hot water storage tank, and when the detected temperature is lower than a predetermined temperature, the heat exchanger is provided. The hot water supply path is switched to the hot water supply from the hot spring.

According to the present invention, when the temperature detected by the temperature detecting means is lower than a predetermined temperature,
It is possible to automatically switch to hot water supply from the heat exchanger, assuming that the temperature of the hot water in the hot water tank is too low to supply hot water.

[0020]

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

(Embodiment 1) FIG. 1 is a configuration diagram of a hot water supply apparatus according to one embodiment of the present invention, and portions corresponding to the above-described conventional example are denoted by the same reference numerals.

In FIG. 1, reference numeral 1 denotes a heat source such as an engine generator, and 2 denotes a waste heat from the heat source 1, for example, water cooling of a gas engine and heating for supplying high-temperature water heated by waste gas of the gas engine. The coil 10 is a hot water storage tank provided with the heating coil 2, a water supply pipe 4 connected to a lower water supply port 3, and a hot water supply pipe 6 connected to an upper tap hole 5. Water supply pipe 4 and hot water supply pipe 6
And a bypass pipe 7, a bypass flow rate control valve 8 is provided in the bypass pipe 7, and a hot water supply flow rate control valve 9 is provided in the hot water supply pipe 6. Have been.

In the hot water storage tank 10, low-temperature water from the water supply pipe 4 is heated and stored by high-temperature water using waste heat from the heat source 1, and the heated hot water is discharged from the upper part as necessary. Hot water is supplied from the sprue 5 through the hot water supply pipe 6, and low-temperature water is supplied from the lower water supply port 3. The hot water storage tank 10 has a function as a heat storage unit.

The above configuration is basically the same as the conventional example.

In this embodiment, even if the temperature of the hot water supplied from the hot water outlet 5 drops due to excessive use of the hot water stored in the hot water storage tank 10, or if the amount of supplied water exceeds the amount of hot water stored In order to be able to use hot water, it is configured as follows.

That is, in this embodiment, the water supplied from the water supply pipe 4 is heated by high-temperature water from the heat source 1 to supply hot water. Hot water path switching means 12 for switching to a path for circulating the heating coil 2 or a path for circulating the heat exchanger 11, and a hot water path switching means for switching to either hot water supply from the hot water storage tank 10 or hot water supply from the heat exchanger 11. And a thermistor 14 as a temperature detecting means for detecting the temperature in the hot water storage tank 10.

The heat exchanger 11 of this embodiment is a double-pipe heat exchanger made of concentric double pipes. High-temperature water from the heat source 1 flows through the annular portion while the inside of the inner pipe is The heat exchange is performed by the flow of water supplied to the heat exchanger, and instantaneous hot water can be supplied by the double-pipe heat exchanger 11.

The high-temperature water path switching means 12 includes a first switching valve 15 for switching the flow path on the outward path from the heat source 1 to the heating coil 2 or the heat exchanger 11, and a flow path on the return path to the heat source 1 for heating. A second switching valve 16 for switching to the coil 2 or the heat exchanger 11, and the two switching valves 15, 16 are switched to the heating coil 2 side or the heat exchanger 11 side so that the high temperature from the heat source 1 is increased. The water circulation path is switched to a path for circulating the heating coil 2 of the hot water storage tank 10 or a path for circulating the heat exchanger 11.

Hot water supply switching valve 13 provided in hot water supply pipe 6
Is to switch either the flow path from the hot water outlet 5 of the hot water storage tank 10 or the flow path from the outlet of the heat exchanger 11 to the hot water supply pipe 6 to switch the hot water supply path.

In the hot water supply apparatus having the above-described configuration, when the hot water tap (not shown) is closed and hot water is not supplied, the first and second switching valves 15 and 16 are located on the heating coil 2 side of the hot water storage tank 10. The high-temperature water circulates through the heating coil 2, and heats the water in the hot water storage tank 10 with the high-temperature water from which waste heat has been recovered, as in the related art, to store heat. At this time, hot water supply switching valve 13 is on the hot water supply path side from hot water outlet 5 of hot water storage tank 10.

Next, when the hot-water tap is opened, water is supplied. On the other hand, when the detected temperature is higher than a predetermined temperature based on the detected temperature detected by the thermistor 14, the hot-water storage tank 10 is sufficiently filled. Assuming that the hot water is stored, hot water is supplied from the hot water supply pipe 4 to the hot water storage tank 10, while hot water is supplied from the hot water storage tank 10 via the hot water supply switching valve 13 and the hot water supply pipe 6 as indicated by the dashed arrow. The predetermined temperature is set in advance by, for example, a remote controller.

If the temperature detected by the thermistor 14 when the hot water tap is opened is lower than a predetermined temperature, it is determined that the temperature of the water in the hot water storage tank 10 is too low to be used, and a controller (not shown) is used. The control means) switches the first and second switching valves 15 and 16 to the heat exchanger 11 side as a circulation path on the heat exchanger 11 side, and sets the hot water supply switching valve 13 to the outlet of the heat exchanger 11. Switch to the heat exchanger 11
Hot water supply path is selected.

Thus, as indicated by solid arrows, the low-temperature water supplied from the water supply pipe 4 is supplied to the heat exchanger 1.
In 1, heat is exchanged with high-temperature water from the heat source 1 to become high-temperature hot water, and hot water is supplied instantaneously via the hot-water supply switching valve 13 and the hot-water supply pipe 6.

When the hot-water tap is closed, the first and second switching valves 15 and 16 are switched to the circulation path on the heating coil 2 side of the hot-water storage tank 10, and the hot-water supply switching valve 13 is connected to the hot-water storage tank. The hot water supply path from 10 is switched.

As described above, when the hot water is sufficiently stored in the hot water tank 10, the hot water is supplied from the hot water tank 10, and when the hot water in the hot water tank 10 is excessively used and the temperature of the water in the hot water tank 10 is too low, Hot water can be supplied from the heat exchanger 11,
Convenience is improved.

(Embodiment 2) FIG. 2 is a block diagram of another embodiment of the present invention, and portions corresponding to FIG. 1 are denoted by the same reference numerals.

In the above embodiment, the heat exchanger 11 is supplied with water from the water supply pipe 4, but in this embodiment, the hot water from the hot water outlet 5 of the hot water storage tank 10 is supplied via the hot water supply switching valve 17. It is configured to be supplied with water.

The hot water supply switching valve 17 is connected to the hot water outlet 5 of the hot water storage tank 10.
From the hot water supply pipe 6 or the inlet 1 of the heat exchanger 11
8 is switched to a pipe 18 to
The hot water supply path is switched to either hot water supply from hot water storage tank 10 or hot water supply from heat exchanger 11.

In this embodiment, when a hot water tap (not shown) is closed and hot water is not supplied, the first and second switching valves 15 and 16 are connected to the hot water tank 1 similarly to the above-described embodiment.
The high-temperature water circulating through the heating coil 2 at the side of the heating coil 2 of the hot water storage tank 1
The water in 0 is heated and stored. At this time, hot water supply switching valve 17 connects the flow path from hot water outlet 5 of hot water storage tank 10 to hot water supply pipe 6 side.

Next, when the hot water tap is opened, water is supplied. On the other hand, based on the detected temperature detected by the thermistor 14, when the detected temperature is higher than a predetermined temperature, the hot water storage tank 10 is sufficiently filled. Assuming that the hot water is stored, hot water is supplied from the hot water outlet 5 of the hot water storage tank 10 through the hot water supply switching valve 17 and the hot water supply pipe 6 as indicated by a broken line arrow.

If the temperature detected by the thermistor 14 when the hot water tap is opened is lower than a predetermined temperature, it is determined that the temperature of the water in the hot water storage tank 10 is too low to be used and a controller (not shown) (not shown) is used. The control means) switches the first and second switching valves 15 and 16 to the heat exchanger 11 side as a circulation path on the heat exchanger 11 side, and sets the hot water supply switching valve 17 to the inlet of the heat exchanger 11. The low-temperature hot water from the hot-water storage tank 10 is supplied to the heat exchanger 11 by switching to the piping 18 on the side.

Thus, as indicated by the solid arrow, the low-temperature hot water supplied from the hot-water storage tank 10 via the hot-water supply switching valve 17 exchanges heat with the high-temperature water from the heat source 1 in the heat exchanger 11. As a result, hot water becomes hot water and is supplied instantaneously through the hot water supply pipe 6.

When the hot water tap is closed, the first and second switching valves 15 and 16 are switched to the circulation path on the heating coil 2 side of the hot water storage tank 10, and the hot water supply switching valve 17 is connected to the hot water storage tank. The hot water supply piping 6
Switch to side.

As described above, when the hot water is sufficiently stored in the hot water storage tank 10, the hot water is supplied from the hot water storage tank 10, and when the hot water in the hot water storage tank 10 is excessively used and the temperature of the water in the hot water storage tank 10 is too low, the instantaneous Hot water can be supplied from the heat exchanger 11,
Convenience is improved.

In this embodiment, the hot water storage tank 10
Low-temperature water is heated to a high temperature in the heat exchanger 11 and supplied.
Hot water can be supplied by heating more efficiently than in the above-described embodiment. In particular, hot water can be supplied via the heat exchanger 11 even if the capacity of the heat source 1 is small.

(Other Embodiments) In the above embodiment, a generator such as an engine generator or a fuel cell is used as a heat source. However, the present invention is not limited to this. Other heat sources such as a condenser may be used.

In the above embodiment, the present invention is applied to the cogeneration system using the waste heat of the generator, but the present invention is not limited to the cogeneration system.

[0048]

As described above, according to the present invention, the internal water supplied from the water supply pipe is heated by the high-temperature water heated by the heat source to store heat, and the water is supplied from the water supply pipe. Since the apparatus is provided with a heat exchanger that supplies hot water by heating the water with the high-temperature water, the hot water supply from the hot water storage tank or the hot water supply from the heat exchanger can be switched and selected, and the convenience is improved.

In particular, by exchanging the low-temperature water from the hot-water storage tank with a heat exchanger, high-temperature water can be efficiently obtained and supplied.

Further, by switching the hot water supply path by detecting the temperature of the hot water storage tank, hot water supply from the hot water storage tank or instantaneous hot water supply from the heat exchanger can be performed automatically.

[Brief description of the drawings]

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

FIG. 2 is a configuration diagram of another embodiment of the present invention.

FIG. 3 is a configuration diagram of a conventional example.

[Description of Signs] 1 Heat source 2 Heating coil 4 Water supply pipe 6 Hot water supply pipe 10 Hot water storage tank 11 Heat exchanger 12 Hot water path switching means 13, 17 Hot water supply switching valve 14 Thermistor

Claims (6)

[Claims] 1. A hot water storage tank for heating internal water supplied from a water supply pipe by high-temperature water heated by a heat source to store heat, and heating water supplied from the water supply pipe by the high-temperature water. A hot water supply device, comprising: a heat exchanger for supplying hot water. 2. A hot water storage tank for storing internal water supplied from a water supply pipe by heating with high-temperature water heated by a heat source, and a hot water supplied from a hot-water supply pipe of the hot water storage tank by the high-temperature water. A hot water supply device, comprising: a heat exchanger for heating and supplying hot water. 3. The hot water supply apparatus according to claim 1, wherein the high-temperature water is heated by waste heat of the heat source, and the heat exchanger is a double-pipe heat exchanger. 4. The hot water supply according to claim 1, further comprising a high-temperature water path switching means for switching a circulation path of the high-temperature water to a path for circulating the hot water tank or a path for circulating the heat exchanger. apparatus. 5. The hot water supply apparatus according to claim 1, further comprising hot water supply path switching means for switching between hot water supply from the hot water storage tank and hot water supply from the heat exchanger. 6. A hot water supply according to claim 5, further comprising temperature detecting means for detecting a temperature of the hot water storage tank, wherein when the detected temperature is lower than a predetermined temperature, a hot water supply path is switched to hot water supply from the heat exchanger. apparatus.