JPH10185332A - Hot-water supplier utilizing solar heat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the driving of a circulation pump, which reduces a hot-water temperature in a hot-water storage tank, and heat the hot-water in the hot-water storage tank efficiently by a method wherein the circulation pump is driven only when the intensity of light is higher than a reference value and a heating medium temperature in a heat collector is higher than the hot-water temperature in the hot-water storage tank by a predetermined value or more. SOLUTION: The output signal of a temperature difference thermostat 10, detecting a temperature difference between the detecting temperature of a high-temperature detecting thermostat 9, measuring a heating medium temperature TH in a heat collector 2, and the detecting temperature of a low-temperature detecting thermostat 9, measuring a hot-water temperature TL in a hot-water storage tank 3, is inputted into the driving and stopping control mechanism 6 of a circulation pump 4. When the intensity of light, detected by a solar battery 5, is higher than a reference value, the temperature difference detected by the temperature difference thermostat 10 is decided whether is it larger than zero or not or the heat medium temperature TH in the heat collector 2 is decided whether is it higher than the hot-water temperature TL in the hot-water storage tank 3 or not. When it is 'YES', 'ON' signal is outputted into the circulation pump 4. Accordingly, the circulation pump 4 is driven only when the intensity of light is higher than a reference value and the heat medium temperature TH in the heat collector 2 is higher than the hot-water temperature TL in the hot-water storage tank 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a solar water heater.

[0002]

2. Description of the Related Art A solar heat collector, a hot water tank for storing hot water used for hot water supply, a heat exchanger provided in the hot water tank, and a heat medium heated by solar heat are collected from the heat collector. A circulating pump that sends a heat medium, which heats hot water in a hot water tank from a heat exchanger to a heat collector and returns the heat medium to a heat collector, has been known from the past. In the hot water supply device, the circulation pump is driven when the luminous intensity of the sun is equal to or more than a reference value, and the circulating pump is stopped when the luminous intensity of the sun is less than the reference value.

[0003]

In the conventional solar hot water supply apparatus, even when the temperature of the heat medium in the heat collector is lower than the temperature of the hot water in the hot water storage tank, when the luminous intensity of the sun is higher than the reference value, The circulation pump is driven, and as a result, there is a problem that the temperature of the hot water storage tank may decrease.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the operation of a pump that lowers the temperature of hot water in a hot water tank, thereby efficiently heating the hot water tank and reducing the power required for operating the pump. A hot water supply device is provided.

[0005]

A solar hot water supply apparatus according to the present invention includes a solar heat collector, a hot water storage tank for storing hot water used for hot water supply, a heat exchanger provided in the hot water storage tank, A circulating pump that sends a heat medium heated by solar heat from a heat collector to a heat exchanger and returns the heat medium that has heated hot water in the hot water tank from the heat exchanger to the heat collector. , A detector that detects the amount of solar radiation, and a detector that detects the temperature difference between the temperature of the heat medium in the heat collector and the temperature of the hot water in the hot water tank. The pump is driven only when the temperature of the heating medium in the vessel is higher than the temperature of the hot water in the hot water tank by a predetermined value or more.

[0006]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a solar hot water supply apparatus of the present invention. The solar hot water supply apparatus (1) includes a solar heat collector (2) for heating a heat medium (usually water), and a hot water supply apparatus. A hot water storage tank (3) for storing hot water to be used, a circulation pump (4) for circulating a heat medium, a solar cell (5), and a drive / stop control mechanism (6) for the circulation pump (4) are provided. ing.

[0008] A heat exchanger (7) is provided in the hot water storage tank (3). The circulation pump (4) sends the heat medium heated by solar heat from the heat collector (2) to the heat exchanger (7), and transfers the heat medium that has heated the hot water in the hot water storage tank (3) to the heat exchanger (7). ) To return to the collector (2). The solar cell (5) has a function of detecting the luminous intensity and driving the circulation pump (4).

Drive / stop control mechanism (6) for circulation pump (4)
Is a high temperature detection thermometer that measures the temperature of the heating medium in the heat collector (2).
(8), low temperature detection thermometer (9) for measuring hot water temperature in hot water tank (3), high temperature detection thermometer (8) and low temperature detection thermometer (9)
And a differential temperature thermometer (10) for detecting a temperature difference between the thermostat and the thermometer.

A drive / stop control mechanism (6) for the circulation pump (4)
Is connected to a solar cell (5) having a function of detecting luminous intensity, and controls the circulation pump (4) as follows.

Referring to FIG. 2, when the luminous intensity is less than the reference value, a signal for turning off the circulation pump (4) is issued regardless of the temperature difference detected by the temperature difference thermostat (10). If the luminous intensity is equal to or higher than the reference value, it is determined whether the temperature difference detected by the temperature difference thermostat (10) is larger than 0, that is, the heat medium temperature TH in the heat collector (2).
Is higher than the hot water temperature TL in the hot water tank (3). If the heat medium temperature TH in the heat collector (2) is higher than the hot water temperature TL in the hot water tank (3), the circulation pump
(4) Output a signal to turn ON. Conversely, if the heat medium temperature TH in the heat collector (2) is lower than the hot water temperature TL in the hot water tank (3), a signal to turn off the circulation pump (4) is issued. Thus, even if the luminous intensity is equal to or higher than the reference value, the circulation pump (4) is not driven unless the heat medium temperature TH in the heat collector (2) is higher than the hot water temperature TL in the hot water tank (3). . Thus,
Only when the luminous intensity is higher than the reference value and the temperature of the heat medium in the heat collector (2) is higher than the temperature of the hot water in the hot water tank (3), the circulation pump
(4) is driven.

Therefore, even in the evening, the luminous intensity is higher than the reference value, while the temperature of the hot water in the hot water storage tank (3) is kept sufficiently high so that the heat in the heat collector (2) is maintained. If the medium temperature drops below the hot water temperature in the hot water tank (3),
Since the circulation pump (4) is not driven to lower the hot water temperature, the hot water in the hot water storage tank is efficiently heated and the power required to operate the circulation pump (4) can be reduced. .

[0013] The luminous intensity in the above embodiment is one amount representing the thermal energy of the sun, that is, the amount of solar radiation.
Of course, the solar radiation may be measured in another unit instead of the luminous intensity. Also, various types of detectors can be used for detecting the temperature difference between the temperature of the heat medium in the heat collector (2) and the temperature of the hot water in the hot water tank (3). In addition, the circulation pump (4) is driven only when the temperature of the heat medium in the heat collector (2) is higher than the temperature of the hot water in the hot water tank (3). 2)
The circulation pump (4) may be driven only when the temperature of the heat transfer medium in the hot water tank (3) is higher than the temperature of the hot water in the hot water storage tank (3) by a predetermined value or more, for example, by 3 ° C. or more.

[0014]

According to the solar water heating apparatus of the present invention, the circulation pump is activated only when the luminous intensity is higher than the reference value and the temperature of the heating medium in the heat collector is higher than the temperature of the hot water in the hot water storage tank by a predetermined value or more. Since it is driven, the circulation pump is not driven so that the temperature of the hot water in the hot water storage tank is reduced, so that the heating of the hot water in the hot water storage tank is efficiently performed and the electric power required for operating the circulation pump is also reduced. Can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a solar hot water supply apparatus according to the present invention.

FIG. 2 is a flowchart showing a control method of the solar water heater according to the present invention.

[Explanation of symbols]

 (1) Solar hot water supply system (2) Solar heat collector (3) Hot water tank (4) Circulation pump (5) Solar cell (solar radiation detector) (7) Heat exchanger (10) Differential temperature thermostat Detector)

Claims (1)

[Claims] 1. A solar heat collector (2), a hot water storage tank (3) for storing hot water used for hot water supply, a heat exchanger (7) provided in the hot water storage tank (3), and a solar heat collector. The heat medium heated in step (2) is sent from the heat collector (2) to the heat exchanger (7), and the heat medium that has heated the hot water in the hot water tank (3) is transferred from the heat exchanger (7) to the heat collector (2). In a solar hot water supply system equipped with a circulation pump (4) for returning heat to the water, a detector (5) for detecting the amount of solar radiation, the temperature of the heat medium in the heat collector (2) and the hot water in the hot water tank (3) A detector (10) for detecting a temperature difference from the temperature, the amount of solar radiation is equal to or higher than the reference value, and the temperature of the heat medium in the heat collector (2) is higher than the temperature of the hot water in the hot water tank (3). A solar hot water supply apparatus characterized in that the pump (4) is driven only when it is higher than a predetermined value.