JPH04126924A - Hot water supply system - Google Patents

Abstract

PURPOSE:To inhibit early corrosion of a hot water supply pipe and reduce the power, by using a refrigerant capable of a phase change from a liquid at an evaporator to a vapor, and providing a head sufficient for transferring the liquefied refrigerant to the evaporator, between the side of a primary piping and a heat transfer part and the side of the evaporator. CONSTITUTION:A hot water reservoir 1 on the roof of a building is supplied with water from a feed water tank 2, and is connected through a hot water supply pipe 4 to the faucets 3 in kitchen and toilet on each floor. On the lower side of the building, an evaporator 5 and a boiler 6 constituting a heat source are connected. A refrigerant subjected to a phase change from liquid to vapor by heat exchanger at the evaporator 5 is fed up to heat exchangers 10, where it undergoes a vapor-to-liquid phase change. The refrigerant liquefied flows down back to the evaporator 5. Thus, the refrigerant is circulated between the evaporator 5 and the heat exchangers 10.... The water in the hot water reservoir 1 is heated, the resulting hot water is reserved in the reservoir 1. Hot water in the hot water supply pipe 4 is maintained at a high temperature by heat exchanger at the heat exchangers 10 near the faucets 3..., so that hot water can be constantly tapped from the faucets 3.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a so-called central hot water supply system that supplies hot water from a hot water storage tank to each kitchen, each room, etc. in buildings, hotels, etc.

<Prior Art> Conventional central hot water supply systems generally include the following.

A. First Conventional Example As shown in the overall system configuration shown in FIG. 5, a hot water storage tank 01 is installed on the roof of a building, etc., and the hot water storage tank 01 is configured to be refilled with water from a water supply tank 02. .

A water supply pipe 04 with a pump 03 interposed in the hot water storage tank 01
A wheeler 06 is connected via a return pipe 05 and a hot water storage tank 01 is configured to store hot water at a high temperature.

Hot water storage tank 01, kitchen and hand washing area on each floor of the building
Each of the provided columns 07 is connected via a hot water supply pipe o9 with a hot water supply pump 08 interposed therein and a return pipe 00, and extends over the hot water storage tank o1, the hot water supply pipe 09, and the return pipe 010. It is constructed so that hot water is constantly circulated and hot water comes out immediately whenever the callan 07 is opened.

011 in the figure indicates a gas pipe that supplies gas to the boiler 06, and 012 in the figure indicates a bypass from the hot water storage tank o1 when the amount of hot water used increases and becomes larger than the amount of hot water supplied by the hot water pump 08. This bypass pipe 012 is provided with a check valve 013.

B. Second Conventional Example As shown in the overall system configuration diagram in FIG.
It is configured to replenish water from + to a closed expansion tank 022 via a water supply pipe 024 equipped with a check valve 023.

A boiler 029 is connected to the expansion tank 022 via a water supply pipe 026 equipped with a pump 025 and a return pipe 028 equipped with an air bleed valve 027.
It is designed to store hot water inside.

The expansion tank 022 and the counters 030 installed in the kitchen, hand wash, etc. on each floor of the building are connected to each other via a hot water supply pipe 032 and a return pipe 033, which have a hot water supply pump 031 interposed therebetween. Expansion tank 022, hot water pipe 032
The high temperature hot water is constantly circulated through the return pipe 033 and the return pipe 033, so that the high temperature hot water immediately comes out whenever the callan o30 is opened.

<Problem to be solved by the invention> However, both of the above first and second conventional examples,
Since high-temperature hot water is constantly circulating in the hot water supply pipes 09 and 032, power is required to constantly drive the hot water pumps 08 and 031, which increases running costs.
There was a drawback that the hot water supply pipes 09 and 032 were susceptible to corrosion due to the constant flow of hot water.

In addition, since large water pressure is applied to the lower floor water pipes 07 and 030, the diameters of the hot water supply pipes 09 and 032 are adjusted to equalize the outflow pressure of hot water regardless of their height differences. However, Karan 07..., 0
30... It is difficult to equalize the mutual outflow pressure,
There was a disadvantage that the hot water supply pipes 09 and 032 at locations where the flow rate was high were more likely to corrode due to the difference in flow rate.

Furthermore, in the case of the first conventional example, the boiler 06 is installed on the top floor, and the gas pipe 011 that supplies gas to the boiler 06
passed through the building, making it unsafe.

On the other hand, in the case of the second conventional example, in order to supply the hot water in the expansion tank 022 to the top floor 030..., a lift approximately equal to the height of the building is required, and the hot water pump 030...
The disadvantage was that the power of the engine was further increased.

The present invention has been made in view of the above circumstances, and the invention as claimed in claim (1) is directed to suppressing early corrosion of hot water supply pipes and making it possible to supply hot water at low cost with less power. The object of the invention as claimed in claim (2) is to improve the heat transfer efficiency when heat is transferred to the hot water supply pipe.

<Means for Solving the Problems> In order to achieve such an object, the present invention provides a hot water supply system of the invention according to claim (1), which includes an evaporator serving as a heat source side, and an evaporator in a hot water storage tank. The primary side piping and/or the hot water supply pipe from the hot water storage tank to the Karan and the heat transfer section are connected via refrigerant piping, and the refrigerant is airtightly connected between the evaporator and the primary side piping and/or the heat transfer section. The refrigerant is configured to circulate and flow, and uses a refrigerant that changes phase from liquid to vapor as heat exchange occurs in the evaporator, and connects the primary side piping and/or each heat transfer section to the evaporator. A head difference sufficient to transfer the phase-changed refrigerant to the evaporator is provided between the evaporator and the evaporator.

Further, as a hot water supply system according to the invention according to claim (2), the heat transfer section according to claim (1) is arranged so that the hot water supply pipe and the refrigerant pipe are in contact with each other so that heat can be transferred thereto. The hot water supply pipe and the refrigerant pipe are each bent in a zigzag shape, and the upper side of the refrigerant pipe is arranged so as to contact the lower side of the hot water supply pipe.

<Operation> According to the configuration of the hot water supply system of the invention according to claim (1), the evaporator serving as the heat source side is provided at the lowest part, and the evaporator and the primary piping in the hot water storage tank and/or the hot water storage tank are connected to each other. The refrigerant flows through the heat transfer section from the tank to the hot water supply pipe to the water supply pipe by natural circulation, and the hot water in the hot water supply pipe is maintained at a high temperature by the latent heat of condensation of the refrigerant, without circulating hot water within the hot water supply pipe. , it is possible to constantly have hot water flowing out of the kalan.

Further, according to the configuration of the hot water supply system of the invention according to claim (2), the refrigerant liquid that is condensed and liquefied due to heat transfer is allowed to flow in the refrigerant pipe at a position far from the side that contacts the hot water supply pipe, while , the refrigerant vapor can be made to flow within the refrigerant piping at a position close to the side that contacts the hot water supply pipe.

<Example> Next, an example of the present invention will be described in detail based on the drawings.

Figure 1 is an overall system configuration diagram showing the first embodiment of the hot water supply system.A hot water storage tank is installed on the roof of a building, etc., and water is supplied from a water supply tank 2 to the hot water storage tank 1. Configured to replenish.

The hot water storage tank 1 and the washers 3 provided in the kitchen, hand wash, etc. on each floor of the building are connected to each other via a hot water supply pipe 4.

An evaporator 5 serving as a heat source is installed on the lower side of the building, and the evaporator 5 and a boiler 6 are connected.

The evaporator 5 and the primary side pipe 7 in the hot water storage tank 1 are connected to each other via a refrigerant vapor pipe 8 and a first refrigerant liquid pipe 9 that constitute a refrigerant pipe, and the evaporator 5 and the primary side pipe 7 in the hot water storage tank 1 Across the primary side piping 7, refrigerant vapor piping 8, and first refrigerant liquid piping 9, the phase changes from liquid to vapor due to heat exchange in the evaporator 5, and from vapor to liquid due to condensation in the hot water storage tank 1. A phase-changing refrigerant is hermetically sealed.

The hot water storage tank 1 is installed at a higher position than the evaporator 5,
As the refrigerant undergoes a phase change from liquid to vapor as a result of heat exchange in the evaporator 5, it rises and is supplied to the hot water storage tank 1.
The refrigerant, whose phase has changed from vapor to liquid due to condensation in the hot water storage tank 1, flows down (J) and is supplied with a sufficient head difference to be returned to the evaporator 5. The hot water is configured to naturally circulate between the evaporator 5 and the hot water storage tank 1.

In addition, a heat exchanger 10 as a heat transfer section is provided at a midway point in the downward direction of the hot water pipe 4, and the heat exchanger 10.
A refrigerant vapor branch pipe 11 branched from the refrigerant vapor pipe 8 and a second refrigerant liquid pipe 12, which constitute refrigerant pipes, are connected in communication with each other, and these heat exchangers 10 and
..., refrigerant vapor branch pipe 11 and second refrigerant liquid pipe 1
2, a refrigerant whose phase changes from liquid to vapor due to heat exchange in the evaporator 5 and from vapor to liquid due to condensation in the heat exchanger 10 is hermetically sealed.

The heat exchanger 10 is installed at a higher position than the evaporator 5, and the refrigerant whose phase has changed from liquid to vapor as the evaporator 5 exchanges heat rises to the heat exchanger 10. ...
At the same time, a sufficient head difference is provided so that the refrigerant whose phase has changed from vapor to liquid by condensation in the heat exchanger 10 is supplied downstream and returned to the evaporator 5G, and the head difference between the vapor and liquid is Due to the phase change, the refrigerant flows into the evaporator 5 and the heat exchanger I.
It is configured to naturally circulate and flow between O...

With the above configuration, the natural circulation Q of the refrigerant heats the water in the hot water storage tank 1 and stores high-temperature hot water, and the heat exchanger 10...
The hot water in the hot water supply pipe 4 is heated and maintained at a high temperature at a location near the hot water supply pipe 4, and the hot water constantly flows out through the pipe 3.

[IJ Nukas R22] is used as the refrigerant. This Freon gas R-22 contains hydrogen and chlorine and decomposes in the troposphere, so it has the advantage of not causing any risk of destroying the ozone layer.

Jul 111 Figure 2 is an overall system configuration diagram showing the second embodiment,
The figure is a sectional view of main parts, and the differences from the first embodiment are as follows.

That is, the refrigerant vapor branch pipe 11 branched from the refrigerant vapor pipe 8 and the hot water supply pipe 4 are provided in contact with each other so that heat can be transferred thereto, and both pipes 4.11 are covered with a heat insulating material 13 to form a heat transfer section. ing.

The other configurations are the same as those of the second embodiment, and the explanation thereof will be omitted by referring to the same figure numbers.

According to the configuration of this second embodiment, the refrigerant vapor branch pipe 11
By the heat transfer between the hot water supply pipe 4 and the hot water supply pipe 4, the hot water in the hot water supply pipe 4 is heated and maintained at a high temperature at a point close to the heat exchanger 3... can be leaked.

FIG. 4 on page JJ1 is a partially cutaway front view showing the third embodiment which is suitable for carrying out the second embodiment. The refrigerant vapor branch pipe 11 is bent so as to be located below the hot water supply pipe 4, and the refrigerant vapor branch pipe 11 is formed at a position far from the side where the condensed and liquefied refrigerant liquid contacts the hot water supply pipe 4. The refrigerant vapor flows down the inner wall surface of the hot water supply pipe 4 at a position close to the side where it comes into contact with the hot water supply pipe 4, thereby improving heat transfer efficiency.

A mild steel pipe is used as the refrigerant vapor branch pipe 11, and can be easily bent to fit around the hot water supply pipe 4.

In the above embodiment, the boiler 6 constitutes the heat source for evaporating the refrigerant liquid in the evaporator 5.
Various configurations such as heaters and heat pumps can be adopted.

In the embodiment described above, both the primary side piping 7 in the hot water storage tank l and the heat transfer portion of the hot water supply pipe 4 are connected to the reactor 5 via the refrigerant piping 8.9.11.12. And hot water storage tank 1
Although the configuration is such that heating is performed both inside the hot water storage tank 1 and inside the hot water supply pipe 4, it may be configured such that only either the inside of the hot water storage tank 1 or the inside of the hot water supply pipe 4 is heated.

<Effect of the invention> According to the hot water supply system of the invention according to claim (1),
Because high-temperature hot water is not constantly flowing in the hot water pipes, only the amount of hot water that is used is allowed to flow through the pipe, the frequency of hot water flowing in the hot water pipes is significantly reduced, and early corrosion of the hot water pipes is avoided. Now you can.

In addition, since it is sufficient to supply only the amount of hot water that is used, for example, even if a hot water storage tank is installed at the bottom and a hot water supply pump is used to pump the hot water, the power required can be significantly reduced, reducing running costs. .

Furthermore, since the evaporator, which is the heat source, is installed at a low position, even if a boiler is used as the heat source for the evaporator,
It is safe because the boiler can be installed at a low location and there is no need to extend the gas pipe to the top of the building.

Further, according to the hot water supply system of the invention according to claim (2), the refrigerant vapor can be made to flow in the refrigerant pipe at a position close to the side that contacts the hot water supply pipe, so that the refrigerant vapor does not come into contact with the refrigerant vapor. The highest temperature side can be brought into contact with the hot water pipe, improving heat transfer efficiency.

[Brief explanation of the drawing]

1 to 4 show examples of the hot water supply system according to the present invention, FIG. 1 is an overall system configuration diagram of the first embodiment, and FIG. 2-1 is an overall system configuration diagram of the second embodiment. , 3rd
The figure is a cross-sectional view of the main part, and FIG. 4 is a cutaway front view of the - section showing the third embodiment. 5 and 6 show a conventional hot water supply system 1, FIG. 5 is an overall system configuration diagram of a first conventional example, and FIG. 6 is an overall system configuration diagram of a second conventional example. . 1...Hot water storage tank 3...Channel 4...Hot water supply pipe 5 -Evaporator 7...Next side pipe in the hot water storage tank 8...Refrigerant vapor pipe 9...First refrigerant liquid pipe 10...Heat exchanger as a heat transfer section 11...Refrigerant vapor branch pipe 12...Second refrigerant liquid pipe

Claims (2)

[Claims] (1) The evaporator, which is the heat source side, and the heat transfer section of the primary side piping in the hot water storage tank and/or the hot water supply pipe from the hot water storage tank to Karan are connected via refrigerant piping, and the evaporator A refrigerant is configured to circulate and flow in a sealed state between the container and the primary side piping and/or the heat transfer section, and the refrigerant has a phase change from liquid to vapor as a result of heat exchange in the evaporator. In addition to using a refrigerant that
A hot water supply system characterized in that a head difference sufficient to transfer a refrigerant whose phase has changed to a liquid to the evaporator is provided between each of the primary side piping and/or the heat transfer section and the evaporator. (2) The heat transfer section according to claim (1) is configured by arranging the hot water supply pipe and the refrigerant pipe so that they are in contact with each other so as to enable heat transfer,
The hot water supply system further includes each of the hot water supply pipe and the refrigerant pipe bent in a zigzag shape, and arranged such that the upper side of the refrigerant pipe contacts the lower side of the hot water supply pipe.