JPH11173680A - Water heating system utilizing solar heat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a hot water temperature rise even in winter when the solar energy is small by providing a control mechanism for regulating a storage hot water amount in a hot water storage tank in response to an amount of the solar energy. SOLUTION: Normally, a hot water storage amount is set so that a water level (water level A) is located above a hot water storage tank 11. But, at the time of a small solar energy in winter, when a water level gauge 21 is set to become a lower water level (water level B) than the level A, it is switched to reduce a supply amount of water level switching valve 20 according to an electric signal. At this time, in the case of taking out the hot water in the tank 11, a second hot water supply tube 18 may be used. In this case, a water amount switching valve 22 is opened. Thus, since the storage amount in the tank 11 can be regulated in response to the solar energy amount, a hot water temperature can be sufficiently raised by reducing the storage amount even in winter. And particularly when using a vacuum type solar heat collector, hot water of high temperature can be easily obtained even in winter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar hot water supply system for supplying hot water using solar heat.

[0002]

2. Description of the Related Art Conventionally, as one of the solar hot water supply systems, a hot water storage tank is disposed at a place away from a solar heat collector, a heat exchanger is built in the hot water storage tank, and a dedicated heat medium (for example, an antifreeze solution or the like) is provided. There is an indirect heating type forced circulation system in which water is supplied to a solar heat collector by a circulation pump to heat the water, and a heated heat medium flows through a heat exchanger to heat water in a hot water storage tank.

[0003] This indirect heating type forced circulation system is known as the most excellent system for preventing freezing of pipes in winter because it can use antifreeze.

[0004]

The types of solar heat collectors are mainly divided into two types: flat-plate type solar heat collectors and vacuum-type solar heat collectors. It has the advantage of high heat collection efficiency and easy access to hot water throughout the four seasons.

[0005] However, even in a system using such a vacuum solar heat collector, the temperature of the hot water in the hot water storage tank may not sufficiently rise in winter when solar energy is low, and additional heating is performed by a boiler. I had to.

[0006] The present invention has been made in view of the above point, and an object of the present invention is to provide a solar hot water supply system capable of raising the temperature of hot water even in winter when solar energy is low. .

[0007]

As a result of repeating various experiments to achieve the above object, the inventor of the present invention supplies water so that the hot water tank becomes almost full in the case of the conventional solar hot water supply system. Therefore, the amount of hot water stored is always constant, but when the solar energy in winter is low, it has been found that reducing the amount of hot water in the hot water tank can significantly increase the temperature of hot water, and have proposed the present invention. Was.

That is, the solar hot water supply system of the present invention comprises a solar heat collector, a hot water storage tank containing a heat exchanger, an outgoing pipe connecting an inlet of the solar heat collector and an outlet of the heat exchanger, and a solar heat collector. A return pipe connecting the outlet of the heat exchanger and the inlet of the heat exchanger; a circulating pump mounted in the middle of the outgoing pipe to circulate the heat medium between the solar heat collector and the heat exchanger; and a heat exchanger. Solar water supply system comprising a reserve tank attached to the outgoing pipe between the outlet of the pump and the circulation pump, a water supply pipe for supplying water into the hot water tank, and a hot water supply pipe for taking out hot water from the hot water tank. And a control mechanism for adjusting the amount of hot water stored in the hot water tank in accordance with the amount of hot water.

Further, the control mechanism according to the present invention is characterized by comprising a water level gauge mounted in the hot water tank for measuring a water level, and a water level switching valve mounted on the water supply pipe.

[0010]

According to the solar hot water supply system of the present invention,
Even if the heat quantity is constant, the quantity of hot water to be exchanged can be reduced, so that the temperature of the hot water tends to rise. Therefore, when the solar energy in winter is low, it is possible to increase the hot water temperature by reducing the amount of hot water stored in the hot water tank.

To adjust the amount of hot water stored in the hot water tank, a water level gauge may be installed in the hot water tank, and a water level switching valve may be installed in the water supply pipe. That is, when the solar energy is low, the water level of the hot water in the hot water storage tank may be set low by the water level meter, and the water supply amount may be reduced by the water level switching valve so that the water level is set to such a low level.

A hot water supply pipe for taking out hot water from the hot water storage tank is usually attached to the ceiling of the hot water storage tank. However, the hot water storage tank used in the present invention has a hot water storage for hot water supply when the water level drops. Another hot water supply pipe may be attached near the center of the body of the tank.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a solar hot water supply system of the present invention will be described in detail based on embodiments.

FIG. 1 is an explanatory diagram showing a solar hot water supply system according to the present invention.

In the figure, a solar heat collector 10 is a vacuum glass tube (outer diameter φ126 mm × total length 2830 mm) in which the surface is selectively absorbed and treated with a width of 116 mm and a length of 2620 m.
m, an iron heat collecting plate having a thickness of 0.4 mm, and an outer diameter φ15.88 mm caulked by a press on the central axis of the iron heat collecting plate.
It uses 12 heat collecting tubes having a form in which a copper heat medium tube having a thickness of 0.6 mm is held and stored by a supporter,
The effective heat collecting area is 3.64 m ² . Hot water tank 11
Is made of stainless steel (outside diameter φ530mm x total length 1445m
m), the hot water storage is about 300 liters. The heat exchanger 12 mounted in the hot water storage tank 11 is made of stainless steel (outer diameter φ16 mm × length 8 m), and has a heat transfer area of:
0.4 m ² , mounting position 50 to 2 from bottom of hot water storage tank 11
The range is 50 m.

The solar heat collector 10 and the hot water storage tank 11 are provided with an outgoing pipe 13 connecting the inlet of the solar heat collector 10 and the outlet of the heat exchanger 12, the outlet of the solar heat collector 10 and the inlet of the heat exchanger 12. Are connected by a return pipe 14 connecting the two.

A circulation pump 15 and a reserve tank 16 are attached to the outgoing pipe 13. The reserve tank 16 is a polyethylene molded product having a capacity of about 2
It is 0 liter. The output of the circulation pump 15 is 100V
115 W, and an antifreeze of polypropylene glycol was used as a heat medium.

When the circulation pump 15 operates, the heat exchanger 1
The heat medium discharged from the storage tank 2 enters the reserve tank 16 from the outgoing pipe 13, further exits from the reserve tank 16, passes through the circulation pump 15, and then flows from the outgoing pipe 13 to the solar heat collector 1.
0 and is heated by the solar heat collector 10. The heat medium heated by the solar heat collector 10 flows from the return pipe 14 to the heat exchanger 12, indirectly heats the water in the hot water storage tank 11, and exits from the heat exchanger 12.

A first hot water supply pipe 17 is attached to the ceiling of hot water storage tank 11, and near the center of the body of hot water storage tank 11,
A second hot water supply pipe 18 is attached. A water supply pipe 19 is attached to the bottom of the hot water storage tank 11, and a water level switching valve 20 is attached in the middle of the water supply pipe 19. Further, a water level gauge 21 is attached to a ceiling portion of the hot water storage tank 11 downward, and a tip end thereof reaches a height substantially at the center of the hot water storage tank 11.

When a certain amount of hot water is taken out of the first hot water supply pipe 17 or the second hot water supply pipe 18, the same amount of water is supplied into the hot water storage tank 11 through the water supply pipe 19. A water amount switching valve 22 is mounted in the middle of the second hot water supply pipe 18, and by closing this valve, when hot water is taken out from the first hot water supply pipe 17, low-temperature hot water flows out of the second hot water supply pipe 18. Can be prevented. Further, a pressure reducing check valve 23 is attached to the water supply pipe 19, and an air release valve 24 and a safety valve 25 are attached to the first hot water supply pipe 17. The set pressure of the pressure reducing check valve 23 is 0.80
kg / cm ² , and the set pressure of the safety valve 25 is 0.9
It is 5 kg / cm ² .

In the case of such a solar hot water supply system, the amount of hot water is normally set so that the water level (water level A) comes above the hot water tank 11, but when the solar energy is low in winter, the water level is higher than the water level A. When the water level gauge 21 is set to a low water level (water level B), the water level of the water level switching valve 20 is switched by an electric signal so as to be reduced. At this time, when the hot water in the hot water storage tank 11 is taken out, the second hot water supply pipe 18 may be used.
2 is released.

[0022]

As described above, according to the solar hot water supply system of the present invention, the amount of hot water stored in the hot water storage tank can be adjusted in accordance with the amount of solar energy. Can be sufficiently increased, and particularly when used with a vacuum solar heat collector, it is useful because high-temperature hot water can be easily obtained even in winter.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a solar hot water supply system of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Solar heat collector 11 Hot water storage tank 12 Heat exchanger 13 Outgoing pipe 14 Return pipe 15 Circulation pump 16 Reserve tank 17 First hot water supply pipe 18 Second hot water supply pipe 19 Water supply pipe 20 Water level switching valve 21 Water level gauge

Claims (2)

[Claims] 1. A solar heat collector, a hot water tank containing a heat exchanger, an outgoing pipe connecting an inlet of the solar heat collector and an outlet of the heat exchanger, an outlet of the solar heat collector, and a heat exchanger. Return pipe connecting the inlet of
Supplying water to the circulation pump for circulating the heat medium between the solar heat collector and the heat exchanger, the reserve tank attached to the outgoing pipe between the outlet of the heat exchanger and the circulation pump, and the hot water tank In a solar hot water supply system comprising a water supply pipe and a hot water supply pipe for taking out hot water from a hot water tank, a control mechanism capable of adjusting the amount of hot water stored in the hot water tank in accordance with the amount of solar energy is provided. Solar hot water supply system. 2. The solar hot water supply system according to claim 1, wherein the control mechanism comprises a water level gauge mounted in the hot water storage tank for measuring a water level, and a water level switching valve mounted on the water supply pipe. system.