JPS628701B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an indirect heat collection type solar heat water heating system that uses a heat medium as a heat collection medium and collects solar heat by operating two pumps via a heat exchanger. be.

A conventional solar hot water supply system of this type was constructed as shown in FIG. That is, a heat collector 1, an expansion tank 2, a heat exchanger 3, and a heat collection pump 4.
a heat exchange circuit 8 formed by a hot water storage tank 6, a heat exchange pump 7, and a heat exchanger 3;
is the basic configuration, and the above-mentioned two pumps are turned on and off by the high temperature side temperature detector T1 provided in the heat collector _1.
and a low-temperature side temperature detector T ₂ installed in the hot water storage tank 6.
It was controlled by a differential temperature thermostat 9 equipped with.

In this case, as shown in FIG. 5, when the temperature of the heat collector 1 rises due to solar heat and there is a temperature difference between it and the water temperature in the hot water storage tank 6, that is, when T ₁ > T ₂ , the heat collector pump 4 and heat exchange pump 7 operate simultaneously. At this time, the temperature of the heat medium in the heat collector 1 has risen, but the temperature of other parts of the heat collector circuit 5 has not yet risen, so at the time of startup, the water in the hot water storage tank 6 is at a low temperature. Heat is exchanged with a low-temperature heat medium through the heat exchanger 3, and the temperature inside the hot water tank 6 decreases. Therefore, solar heat collection was not effectively utilized, and the heat exchange pump 7 itself could not be said to be operating properly.

The purpose of the present invention is to eliminate such conventional drawbacks, and to prevent the water temperature in the hot water storage tank from decreasing when the pump is started, and to effectively utilize solar heat by operating the heat exchange pump appropriately. That is.

In order to achieve this objective, the present invention uses a heat medium as a heat collection medium, a heat collection pump is installed on the primary side, and a heat collection pump is installed on the primary side.
A heat exchanger having a heat exchange pump on the next side and exchanging heat between the heat medium in the collector heated by solar heat and the water in the hot water storage tank is provided, and the high temperature side temperature detects the temperature of the collector. A differential temperature thermometer for a heat collection pump that controls on/off the heat collection pump, which has a temperature detection end that includes a detector and a first low temperature side temperature detector that detects the water temperature in the hot water storage tank, and the heat exchanger. A high-temperature side temperature detector that detects the heat medium temperature at the primary side inlet of the tank and a second low-temperature side temperature detector that detects the water temperature in the hot water storage tank are used as temperature detection terminals, and the heat exchange pump is turned on and off. The heat exchange pump is provided with a differential temperature thermostat for the heat exchange pump to be controlled, and a control relay that enables the heat exchange pump to operate only when the heat collection pump is in operation.

With this configuration, the start and stop of the heat collection pump and heat exchange pump are individually controlled by two temperature difference thermostats. First, when a temperature difference occurs between the heat collector and the hot water storage tank, When the pump operates to raise the temperature of the heat medium in the heat collection circuit, and then a temperature difference is created between the primary inlet of the heat exchanger and the hot water storage tank, the heat exchange pump starts operating, but Therefore, there is no need to lower the water temperature in the hot water storage tank. Furthermore, at this time, the heat exchange pump is turned on and off only when the heat collection pump is in the ON state, according to the heat collection pump start/stop signal, so there is no wasteful operation of the heat exchange pump. This is due to the restriction that heat exchange cannot be performed unless fluid flows on both the primary and secondary sides as a condition for heat exchange.

Hereinafter, one embodiment of the present invention will be described based on the drawings. In FIG. 1, the same components as those in FIG. 4 are given the same numbers. In FIG. 1, the high-temperature side temperature sensor _T1 of the differential temperature thermometer 9a for starting and stopping the heat collecting pump 4 is provided in the heat collector 1, and the low-temperature side temperature sensor _T2 is provided in the hot water storage tank 6, and The high temperature side temperature sensor _T3 of the differential temperature thermometer 9b for starting and stopping the heat exchange pump 7 is located at the primary side inlet of the heat exchanger 3 of the heat collecting circuit 5, and the low temperature side temperature sensor _T4 is located inside the hot water storage tank 6. In addition, a heat exchange pump 7 is provided.
The operation of the heat exchange pump 7 is controlled by the control relay 10, and the operation of the heat exchange pump 7 is interlocked by the operation of the heat exchange pump 4.
0, this is possible only when the heat collecting pump 4 is in operation.

Next, the operation of the two pumps in the above configuration will be explained using FIGS. 2 and 3. When the solar radiation becomes stronger and the heat medium temperature in the heat collector 1 rises, and a temperature difference occurs between the water temperature in the hot water storage tank 6, that is, T ₁ > T ₂
When this happens, the heat collection pump 4 is first activated by the temperature difference thermometer 9a. After this, if a temperature difference occurs between the primary side inlet of the heat exchanger 3 in the heat collecting circuit 5 and the water temperature in the hot water storage tank 6, that is, if T ₃ > T ₄ , the heat collecting pump 4
The heat exchange pump 7 will operate under the condition that the heat exchange pump 7 is in operation. By operating these two pumps 4 and 7, solar heat obtained by the heat collector 1 passes through the heat exchanger 3 to increase the water temperature in the hot water tank 6.

In this way, first, only the heat collecting pump 4 is operated, and after the temperature of the heat medium in the heat collecting circuit 5 rises and a temperature difference is created between the primary side inlet of the heat exchanger 3 and the water temperature in the hot water storage tank 6, In other words, the heat exchange pump 7 operates only under the condition that the temperature inside the hot water tank 6 does not drop even after heat exchange. Utilization is improved and wasteful operation of the heat exchange pump 7 is eliminated.

As described above, according to the solar water heating system of the present invention, two temperature difference thermometers are provided to separately control the heat collection pump and the heat exchange pump, and the operation of the heat exchange pump is controlled by the operation of the heat collection pump. Control by signals eliminates the risk of the water temperature in the hot water storage tank dropping when the pump is started, as was the case in the past, and also reduces the operating time of the heat exchange pump, saving power. Furthermore, since two pumps are less likely to start at the same time, the starting current becomes smaller and the load on relays becomes smaller. Further, since the temperature difference values and differentials of the two temperature difference thermometers can be set separately, it is possible to operate each pump with an appropriate temperature difference.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of a solar water heating system according to an embodiment of the present invention, and Fig. 2 shows the amount of solar radiation according to the present invention.
Figure 3 is a conceptual diagram of the control sequence according to the present invention, Figure 4 is a configuration diagram of a conventional solar hot water supply system, and Figure 5 is a diagram of the conventional solar heat water heating system. quantity, hot water tank temperature,
It is a pattern diagram of heat collection pump and heat exchange pump operation. 1... Heat collector, 3... Heat exchanger, 4... Heat collection pump, 5... Heat collection circuit, 6... Hot water storage tank, 7... Heat exchange pump, 8... Heat exchange circuit, 9a, 9b...
Differential temperature thermostat for starting/stopping the heat collection pump and differential temperature thermostat for starting/stopping the heat exchange pump, 10...Control relay, T ₁ , T ₂
...High temperature side temperature detector and low temperature side temperature detector of the differential temperature thermometer for starting and stopping the heat exchange pump, T ₃ , T ₄ ...High temperature side temperature detector and low temperature side temperature of the differential temperature thermometer for starting and stopping the heat exchange pump Detector.

Claims (1)

[Claims] 1 Using a heat medium as a heat collection medium, it has a heat collection pump on the primary side and a heat exchange pump on the secondary side, and heats the heat medium in the collector and water in the hot water storage tank, which has been heated by solar heat. A heat exchanger for exchanging is provided, a high-temperature side temperature detector for detecting the temperature of the heat collector and a first low-temperature side temperature detector for detecting the water temperature in the hot water storage tank are used as temperature detection ends, and the heat collecting A differential temperature thermometer for the heat collection pump that controls on/off of the pump, a high temperature side temperature detector that detects the heat medium temperature at the primary side inlet of the heat exchanger, and a second low temperature sensor that detects the water temperature in the hot water storage tank. The side temperature sensor is used as the temperature detection end, and the heat exchange pump is turned on and off.
A hot water supply system using solar heat, comprising: a differential temperature thermostat for a heat exchange pump that is turned off; and a control relay that enables the heat exchange pump to operate only when the heat collection pump is in operation.