JP2012077925A - Solar water heat system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar water heat system which does not determine the shortage of an amount of a heating medium simply based on decline in a liquid level but accurately determines whether the heating medium is truly short in amount, and thus, can securely avoid the generation of false information and erroneous treatment caused by the false information.SOLUTION: When a low liquid level electrode is brought into an off-output state (YES in S1), it is determined whether a boiling condition is satisfied (S3). When the boiling condition is satisfied and an on-output state of the low liquid level electrode is continued during measurement by a second timer (S5, YES in S6), it is determined that the shortage of the amount of the heating medium does not actually occur and a drought counter is reset so as not to output error information (S7). Even if the boiling condition is satisfied and if the on-output state of the low liquid level electrode is not continued, the error information is issued (NO in S5, S9). While the boiling condition is not satisfied yet, when a time by a first timer comes, the error information is issued (YES in S10, S9).

Description

  According to the present invention, solar heat collection is performed by forcibly circulating a heat medium between a heat exchanger for heat exchange heating of hot water in a hot water storage tank and a solar heat collection panel by operating a circulation pump. As for the solar hot water system used to store heat in a hot water storage tank and use this hot water for hot water supply, etc., in particular, it is possible to accurately determine the occurrence of a shortage of heat medium in the heat collection circuit and issue an alarm. Related to technology.

  Conventionally, although not intended for solar hot water systems, in order to avoid inconveniences such as water collapse due to air intrusion into the circulation path, the circulation path is intended for a heating device that circulates the heat medium in the circulation path. If the inside becomes a low pressure state due to the attenuation of the heat medium, it is proposed that the heat medium is replenished after the heat medium circulation to maintain the inside of the circulation path in a pressurized state to prevent water collapse (for example, Patent Document 1).

  In addition, although not intended for the solar hot water system as described above, an air tank equipped with an air vent means is integrally attached to the upper space of the tank constituting the hot water boiler in a sealed hot water boiler. It has also been proposed to issue an alarm if an internal water level drop is output by a water level sensor provided at a predetermined level in the air tank (see, for example, Patent Document 2).

Japanese Patent Application Laid-Open No. 2002-276958 JP 2010-175156 A

  By the way, in the solar hot water system, for example, a circulation path extending between a system main body such as a hot water storage tank installed on the ground and a heat collecting panel installed on a roof of a house, for example, uses a PE (polyethylene) pipe or the like. Since it is piped, air (oxygen) may enter the circulation path from the outside through the pipe wall. However, in recent years, with the widespread use of solar heat, it is becoming more common to install heat collection panels at higher places than before (for example, on the roof of a three-story house). The difference in height between the circulatory path and the circulatory path is more likely to fall into a negative pressure tendency. For this reason, there is a concern that the air permeation amount from the tube wall tends to increase. Here, normally, if the liquid level of the heat medium, which is a liquid part, falls below a predetermined liquid level due to such air permeation or the like, it is detected by a liquid level sensor. By detecting and notifying that the amount of the heat medium has fallen (notice of drought), the circulation pump is prevented from idling.

  However, if the drought notification is performed based on the detection of the liquid level drop by the liquid level sensor, there is a possibility of causing an erroneous report or an erroneous process based on the erroneous report. That is, the circulating operation of the heat medium is not performed for a long time, and the air that has permeated from the wall of the PE pipe that constitutes the circulation path and accumulated inside the gas is liquid-liquid at a time in the next circulating operation. There is a possibility that the gas-liquid separation unit may be filled with a large amount of air by flowing into the separation unit. In this case, the liquid level of the internal heat medium is lower than the liquid level sensor, and drought notification is executed. However, if the amount of heat medium itself is not insufficient, the drought notification is falsely reported. Therefore, various handling processes will be performed based on the misinformation.

  The present invention has been made in view of such circumstances, and the object of the present invention is not to determine whether the amount of heat medium is insufficient based on the occurrence of a decrease in the liquid level, but to truly reduce the amount of heat medium. An object of the present invention is to provide a solar water heating system that can accurately determine whether or not a fault has occurred and reliably avoid the occurrence of misreporting or misprocessing due to misreporting.

  In order to achieve the above object, in the present invention, a heat collecting panel for collecting solar heat and heating a heat medium, a hot water storage tank, a heat exchanger for heat exchange heating of hot water in the hot water storage tank, and a circulation Solar hot water provided with a heat collection circuit that heats and heats hot water in the hot water storage tank to store heat as hot water by circulating a heat medium between the heat collection panel and the heat exchanger by operating a pump The following specific items were prepared for the system. That is, the heat medium detecting means for detecting and outputting the amount of the heat medium in the heat collecting circuit, and the amount of heat medium is insufficient when the detection related to the decrease in the amount of the heat medium is output by the heat medium detecting means. A heating medium amount shortage determining means for determining whether or not a gas generation condition is satisfied, and a bubble generation condition satisfaction determining means for determining whether or not an environmental condition capable of generating bubbles in the heat collecting circuit is satisfied. To do. Then, after receiving the output related to the detection of the decrease in the amount of the heat medium from the heat medium detecting means as the heat medium amount shortage determining means, at least the environmental condition related to bubble generation is satisfied by the bubble generation condition establishment determining means The output status from the heat medium detection means is monitored until it is determined, and when the output related to the decrease detection is not resolved, it is determined that the heat medium amount is insufficient, and an alarm relating to the shortage of the heat medium is output. A configuration is defined (claim 1).

  In the case of the present invention, when only the detection related to the decrease in the amount of the heat medium is output by the heat medium detection means, the warning (error notification) regarding the shortage of the heat medium is not performed, and at least the bubble generation condition establishment determination means generates bubbles. Until it is determined that the environmental condition is satisfied, and during that time, it is determined whether or not the heat medium amount deficiency judging means is truly deficient in the heat medium amount. If the output related to the decrease detection is not eliminated, an alarm relating to the shortage of the heat medium is output. That is, if an environmental condition related to the generation of bubbles is established, the heat medium may flow in the heat collection circuit as the bubbles are generated, and the detection state by the heat medium detection means may change. Thus, if the output related to the decrease detection from the heat medium detecting means is eliminated, it can be determined that the heat medium amount is not actually insufficient. On the other hand, even if such a flow of the heat medium occurs, if the output related to the decrease detection from the heat medium detecting means is still not resolved, it is determined that the amount of the heat medium is actually insufficient. Will get. For this reason, it is possible to avoid the occurrence of false detection / reporting about the shortage of the heat medium, but when it is determined that the heat medium amount is actually insufficient, an alarm is accurately output about the shortage of the heat medium. To get. As a result, it is possible to reliably avoid the occurrence of misinformation and the occurrence of erroneous processing due to the misinformation.

  In the solar hot water system of the present invention, the heating medium temperature detecting means for detecting the temperature of the heating medium in the heat collecting panel or a temperature equivalent to the heating medium temperature is provided, and the heating medium temperature detection is used as the bubble generation condition establishment judging means. If the temperature of the heat medium detected by the means is equal to or higher than the set temperature, it can be determined that the environmental condition relating to the generation of bubbles is established (claim 2). As a result, the heat medium in the heat collection panel is boiled by receiving strong solar heat. As a result, the heat medium expands in volume or bubbles are generated in the heat collection panel. It becomes possible to accurately determine whether or not the generation condition of the phenomenon flowing in the heat circulation circuit is satisfied. As a result, the determination by the heat medium amount shortage determination means can be performed more accurately.

  In the solar hot water system of the present invention, the solar hot water system includes a timer for measuring a stop duration time that elapses in a state where the circulation pump is stopped, and the stop elapsed time timed by the timer as the bubble generation condition establishment determination means. If the set time value is exceeded, it can be determined that the environmental condition related to the bubble generation is satisfied (claim 3). In this way, that is, in addition to the case where bubbles are generated due to the above-mentioned boiling, if the circulation pump is stopped, air permeates through the tube wall of the path constituting the heat collecting circuit. As a result of this invasion, bubbles will be generated in the heat collection circuit, so whether or not the generation condition is satisfied for the phenomenon that affects the detection of the amount of the heat medium based on the generation of such bubbles. Can be accurately determined. As a result, the determination by the heat medium amount shortage determination means can be performed more accurately.

  As described above, according to the solar hot water system of the present invention, at least air bubbles are generated without performing an alarm relating to a shortage of the heat medium only when the detection related to the decrease in the heat medium amount is output by the heat medium detection means. The system waits until it is determined by the generation condition establishment determination means that the environmental condition relating to bubble generation is established, and during that time, the heat medium amount shortage determination means determines whether or not the heat medium amount is truly insufficient. However, if the output related to the decrease detection from the heat medium detecting means is still not resolved, an alarm relating to the shortage of the heat medium is output. For this reason, it is possible to avoid the occurrence of false detection / reporting about the shortage of heat medium, but when it is determined that the heat medium amount is actually insufficient, a warning is given about the shortage of heat medium accurately. It becomes possible to output. As a result, it is possible to reliably avoid the occurrence of misinformation and the occurrence of erroneous processing due to the misinformation.

  In particular, according to claim 2, when the heat medium temperature detected by the heat medium temperature detecting means is equal to or higher than the set temperature, it is determined that the environmental condition related to the bubble generation is satisfied, Whether or not is satisfied can be specifically determined, and the operation of the circulation pump can be performed more accurately. As a result, the determination by the heat medium amount shortage determination means can be performed more accurately.

  According to the third aspect of the present invention, in the heat collecting panel, it is determined that the environmental condition related to the generation of bubbles is established if the stop duration of the circulating pump measured by the timer exceeds the set time value. When bubbles are generated on the basis of reasons other than the occurrence of boiling, that is, when the operation stop state of the circulation pump continues, the air that penetrates through the pipe wall of the circulation path increases and bubbles are generated. However, it is possible to more accurately determine whether or not the bubble generation condition is satisfied by the timer. As a result, the determination by the heat medium amount shortage determination means can be performed more accurately.

It is a mimetic diagram showing an embodiment of a solar hot water system concerning the present invention. It is a block diagram which shows the structure which concerns on the operation control of the solar hot water system of FIG. It is a flowchart which concerns on a heat medium amount shortage determination process. It is explanatory drawing which shows the 1st example of a phenomenon concerning the liquid level fall of a heat carrier, and the phenomenon following this. It is explanatory drawing which shows the 2nd example of a phenomenon concerning the liquid level fall of a heat carrier, and the phenomenon following this. It is explanatory drawing which shows the 3rd example of a phenomenon concerning the liquid level fall of a heat carrier, and the phenomenon following this.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a solar water heating system according to an embodiment of the present invention. In the figure, reference numeral 1 is, for example, a system main body installed on the ground, 2 is a heat collection panel for collecting solar heat by a heat medium (for example, antifreeze) passing through the inside, 3 is a hot water storage tank, 4 is a heat collection panel 2 And a heat collecting circuit that stores heat from the heat medium as hot water in the hot water storage tank 3 by circulating a heat medium between the heat exchanger 43 in the hot water storage tank 3 and a hot water storage tank for tap water and the like from the outside A water supply passage for supplying water into 3, 6 is a hot water supply passage for supplying hot water to the hot water tap (not shown) using hot water stored in the hot water storage tank 3, and 7 is a controller for controlling the operation of this solar hot water system. .

  The heat collection panel 2 is installed, for example, on the roof of a house, and a heat collection panel temperature sensor 21 as heat medium temperature detection means for detecting the temperature of the fins constituting the heat collection panel 2 is installed in the vicinity of the top position. . The fin temperature detected by the heat collection panel temperature sensor 21 is equivalent to the heat medium temperature Ts of the heat medium that has been most heated by heat collection, and the heat medium temperature Ts is detected by detecting the fin temperature. It is like that.

  The hot water storage tank 3 is an airtight container configured in a hermetic manner by, for example, stainless steel. The hot water storage tank 3 is provided with a hot water storage tank temperature sensor 31 that detects the temperature Tt of hot water or water (hereinafter referred to as “hot water”) near the bottom of the hot water storage tank 3. The upstream end of the water supply channel 5 is connected to an external water pipe or the like, and the downstream end is connected to the bottom of the hot water storage tank 3 via a check valve (not shown). A water supply temperature sensor 51 for detecting a water supply temperature and a water supply flow rate sensor 52 for detecting a water supply flow rate are interposed in the water supply channel 5. Further, the upstream end of the hot water supply passage 6 is connected to the top of the hot water storage tank 3, and a hot water temperature sensor 61 for detecting the temperature of the hot water discharged from the hot water storage tank 3 is interposed near the top of the hot water storage tank 3. .

  The heat collection circuit 4 circulates the heat medium between the heat collection panel 2 and the heat storage heat exchanger (for example, a coil heat exchanger) 43 in the hot water storage tank 3 through the circulation path 42 by the operation of the circulation pump 41. It is comprised as follows. The circulation path 42 is provided with a forward path 42 a that leads from the vicinity of the top of the high-temperature heat medium that has been passed through the heat collection panel 2 and led to the inlet side of the heat storage heat exchanger 43 in the hot water storage tank 3. In addition, the heat storage heat exchanger 43 is configured to include a return path 42b for deriving the heat medium having a low temperature by heat exchange from the outlet side of the heat storage heat exchanger 43 and returning it to the bottom of the heat collecting panel 2. In the circulation path 42 including the forward path 42a and the return path 42b, a portion extending between the system main body 1 and the heat collecting panel 2 is piped using, for example, a PE (polyethylene) pipe.

  In addition, a semi-sealed accumulation tank 44 is interposed in the return path 42 b formed in the system main body 1, and the top of the accumulation tank 44 communicates with the bottom of the reserve tank 45 via a communication pipe 451. . The heat medium and / or air overflowing from the accumulation tank 44 is allowed to escape into the reserve tank 45 through the communication pipe 451. A gas-liquid separation unit is configured by a combination of the accumulation tank 44 and the reserve tank 45. Further, the accumulation tank 44 is provided with a low liquid level electrode 441 as a low liquid level sensor for detecting the presence of a heat medium at a low liquid level set as a lower limit liquid level at a predetermined liquid level on the bottom side. If the low liquid level electrode 441 is energized (ON output) through the heat medium, the liquid level of the heat medium in the accumulation tank 44 is above the lower limit liquid level, and if the low liquid level electrode 441 is in the non-energized state (OFF output) It is detected that the position has dropped to below the lower limit liquid level. The low liquid level electrode 441 constitutes a heat medium detecting means, and based on the output information from the low liquid level electrode 441, the heat medium amount shortage determining means 73 described later determines that the heat medium amount is short and an error notification is output. In such a case, the operation of the circulation pump 41 is forcibly stopped by the controller 7, thereby avoiding the idling operation of the circulation pump 41.

  The circulation pump 41 is constituted by a variable flow pump (for example, a DC pump), and its discharge capacity can be adjusted up or down. In the case of a DC pump, if the current value is increased, the rotational speed increases and the discharge amount increases, and if the current value is decreased, the rotational speed decreases and the discharge amount is reduced.

  The above solar hot water system is controlled by the controller 7 in response to the output of the input setting signal / operation signal from the remote controller 71 and the output of the detection signals from the temperature sensors 21, 31 and the low liquid level electrode 441. It has become. The controller 7 includes an MPU, a memory, and the like, and various controls are performed by executing a program installed in advance and a control circuit. The controller 7 includes a heat collection operation control means 72 for performing heat collection operation, a hot water supply control means (not shown), etc., as shown in FIG. As a configuration, the heat medium amount shortage determining means 73 for determining whether or not the amount of the heat medium in the heat collection circuit 4 is insufficient, and determining whether or not a condition for causing boiling in the heat collection panel 2 is satisfied. And a first timer 75, a second timer 76, and a third timer 77 that are used for the determination process in the boiling condition establishment determination means 74 and the heat medium shortage determination means 73.

  First, the heat collection operation control by the heat collection operation control means 72 will be briefly described. Based on the hot water temperature Tt detected by the hot water tank temperature sensor 31, for example, it is confirmed that the amount of heat stored in the hot water tank 3 is insufficient. In addition, it is confirmed that the heat medium temperature Ts detected by the heat collecting panel temperature sensor 21 is higher than the hot water temperature Tt by a predetermined temperature difference α ° C. (for example, 6 ° C.). After confirming the establishment of the above, the circulation pump 41 is operated to start the heat collecting operation.

  As a result, a high-temperature heat medium is supplied from the heat collecting panel 2 to the heat storage heat exchanger 43 through the outgoing path 42a, and the hot water in the hot water storage tank 3 is heat-exchanged and heated in the heat storage heat exchanger 43. The heated heat medium is returned to the heat collecting panel 2 through the return path 42b. The heat medium returned to the heat collection panel 2 is reheated while proceeding to the top in the heat collection panel 2, and the heat medium that has become high temperature is supplied to the heat storage heat exchanger 43 through the forward path 42a. So that it is circulated. Then, the hot water in the hot water storage tank 3 is heat-exchanged and heated, so that the amount of heat collected by the heat transfer medium moves to the hot water in the hot water storage tank 3 and is stored in the hot water storage tank 3 as hot water storage. .

  The heat medium amount shortage determining means 73 is configured to start processing when the detection signal from the low liquid level electrode 441 is changed from the normal ON output to the OFF output. Originally, if there is an OFF output from the low liquid level electrode 441, a corresponding process such as immediately informing the error that the amount of the heat medium is insufficient and prohibiting the operation of the circulation pump 41 (prohibiting the heat collecting operation) is executed. However, in this embodiment, even if there is an OFF output from the low liquid level electrode 441, there is a possibility that the output is temporary and accidental. An error notification is not performed immediately by merely setting a temporary error state with the drought counter of the water, but a standby state is set for a predetermined period, and a predetermined determination process as described later is performed by the heat medium shortage determination means 73 during that period. In addition, error notification is performed in a predetermined case such that the output from the low liquid level electrode 441 does not recover to the ON output.

  The boiling condition establishment determining means 74 determines whether or not an environmental condition for generating bubbles in the circulation path 42 is established. For example, the heating medium in the heat collecting panel 41 is boiled by receiving strong solar heat. As a result, the heat medium expands in volume or bubbles are generated in the heat collection panel, which may cause a phenomenon that the heat medium falls from the heat collection panel into the semi-enclosed heat collection circuit. It is determined whether or not a certain condition is satisfied. Then, this determination result is used for the determination process by the heat medium amount shortage determination means 73. Whether or not the boiling condition is satisfied is determined as follows.

  That is, as the first determination process, it is determined whether or not the heat medium temperature Ts detected by the heat collecting panel temperature sensor 21 exceeds a boiling temperature Tf set in advance as the temperature at which the heat medium boils. The boiling temperature Tf is, for example, 80 ° C. when the heat medium is an antifreeze liquid. Specifically, if the condition that the set elapsed time elapses after the state where the heat medium temperature Ts exceeds the boiling temperature Tf continues for a predetermined setting duration time, it is determined that the boiling condition is satisfied.

  As a second determination process, whether or not the elapsed time (stop continuation time) during which the circulation pump 41 has been in the operation stop state is equal to or longer than a set time ts (for example, 100 hours) is measured by the third timer 77. judge. If the condition that the operation stop state continues for the set time ts or more is satisfied, air enters the inside of the tube wall portion of the circulation path 42 constituted by the PE pipe, and bubbles of a predetermined amount or more are generated. That is, it is determined that the same phenomenon as that in the case of boiling occurs, and it is determined that the boiling condition is satisfied. In short, the boiling condition establishment determining means 74 is the boiling condition for both the generation of bubbles accompanying the occurrence of boiling in the heat collecting panel 2 and the generation of bubbles associated with the intrusion of air through the tube wall of the circulation path 42. It is treated that

  Next, processing based on the heat medium amount shortage determining means 73 and the boiling condition accumulation determining means 74 will be described with reference to the flowchart of FIG. These processes are executed in parallel with the heat collection operation control.

  First, determination processing is started when the detection signal from the low liquid level electrode 441 changes from ON output to OFF output (YES in Step S1), and a temporary error state occurs by setting “1” to the drought counter. The first timer 75 is started (step S2). The circulation pump 41 stops its operation. The first timer 75 may be set to the same time setting (for example, 100 hours) as the third timer 77 used for the determination of the boiling condition, and waits until the time measurement by the first timer 75 ends. A determination is made as to whether the amount of heat medium is insufficient while the standby time elapses. In the drought counter, “0” represents a normal state, “1” represents a provisional error state (provisional heat medium shortage state), and “2” represents a true error state (true heat medium shortage state).

  Next, it is determined whether or not the boiling condition is satisfied (step S3). If the boiling condition is satisfied (YES in the store), the second timer 76 is started (step S4). In the second timer 76, if the boiling phenomenon occurs, the heat medium in the heat collecting panel 2 expands in volume and the heat medium is returned to the accumulator tank 44, or if it cools, the heat medium overflowing in the reserve tank 45 is overflowed. Is returned to the accumulator tank, a time (for example, 48 hours) for determining the movement of the heat medium caused by the boiling phenomenon is set. That is, even if the amount of the heat medium actually falls (drought), when the boiling phenomenon occurs, the heat medium returns to the accumulation tank 44 as described above and the low liquid level electrode 44 is temporarily turned on. In some cases, a grace period is set to accurately determine the situation.

  If boiling occurs, the heating medium returns to the accumulation tank 44 and the liquid level recovers. Therefore, it is determined whether or not the detection signal from the low liquid level electrode 44 continues the ON output (step S5). If it is ON output, it is confirmed whether or not the second timer 76 continues until the time is up (YES in step S5, NO in step S6). If the low liquid level electrode 441 continues the ON output state until the second timer 76 expires (YES in step S6), the OFF output in step S1 is temporary or accidental. It is determined that the amount is not insufficient, and the drought counter is reset (returned to “0”). That is, error notification and subsequent processing are not performed.

  An example of the phenomenon corresponding to the above steps S1 to S7 will be described with reference to FIG. 4. First, air accumulates in the upper part of the accumulator tank 44 in the first stage (see the upper part of FIG. 4), and the heat in the accumulator tank 44 is increased. Even if the liquid level is lower than that of the low liquid level electrode 441 and the low liquid level electrode 441 enters the OFF output state, boiling occurs in the heat collecting panel 2 as the second stage (see the middle part of the figure). The heat medium expands in volume, the heat medium returns to the accumulation tank 44, and the low liquid level electrode 441 recovers to the ON output state. At this time, the air accumulated in the upper part of the accumulation tank 44 overflows and is pushed out to the reserve tank 45 through the communication pipe 451 together with the heat medium. As the third stage (see the lower part of the figure), when the heating medium cools after boiling, the circulation path 42 tends to have a negative pressure, so that the heating medium is returned from the reserve tank 45 to the accumulation tank 44. Thus, the heat medium is filled in the circulation path 42. In the case of the phenomenon example of FIG. 4, the low liquid level electrode 441 continues to be in an ON output state until the heat medium cools after boiling. Based on the establishment of the above phenomenon, it is determined that the provisional detection of the shortage of the heat medium by the drought counter, which has not actually reached the shortage of the heat medium, is a false detection.

  On the other hand, when the boiling condition is satisfied (YES in step S3) and the low liquid level electrode has once recovered to the ON output state, the ON output does not continue until the second timer 76 times out (step S4, S4). YES in step S5, NO in step S6, NO in step S5), or although the boiling condition is satisfied (YES in step S3), the low liquid level electrode 441 does not turn on but remains off. Is maintained (NO in step S4 and step S5), the following processing is performed. That is, the drought counter is set to “+1” to be “2” in total (step S8), and an error notification that the amount of heat medium is insufficient is performed using the remote controller 71, for example (step S9). Based on this error notification, the controller 7 performs processing such as prohibiting the operation of the circulation pump 41.

  An example of the phenomenon corresponding to the case where the determination in step S5 is “NO” will be described with reference to FIG. 5. First, in the first stage (see the upper part of FIG. 5), for example, the robot enters the circulation path 42. The accumulated air flows into the accumulator tank 44 at once, and the heat medium is pushed out to the reserve tank 45, so that the low liquid level electrode 441 is turned off and collected as the second stage (see the middle part of the figure). When boiling occurs in the heat panel 2, the heat medium expands in volume, and the heat medium returns to the accumulation tank 44, so that the low liquid level electrode 441 once recovers to the ON output state. At this time, the heat medium in the reserve tank 45 also returns to the accumulation tank 44. As the third stage (see the lower part of the figure), when the heat medium cools after boiling, the inside of the circulation path 42 tends to be negative pressure, so that the inside of the reserve tank 45 is sucked from the accumulation tank 44. Since the inside of the reserve tank 45 is almost empty, air is sucked in and the inside of the accumulation tank 44 remains empty. In the case of the phenomenon example in FIG. 5, it is determined that the amount of the heat medium is really insufficient, and the drought counter is set to “2” to perform error notification.

  On the other hand, although it is determined whether or not the boiling condition in step S3 is satisfied until the first timer 75 times out (NO in step S3, NO in step S10), the first timer 75 is maintained without the boiling condition being satisfied. If the time has expired (YES in step S10), the process proceeds to step S9, and an error notification that the amount of heat medium is insufficient is performed using the remote controller 71, for example. Although it is unclear whether the amount of heat medium is really insufficient or not, if the standby time of the first timer 75 (determination time by the heat medium amount insufficient determination means 73) is excessively extended, the amount of heat medium is truly insufficient. Therefore, when the first timer 75 expires, the error notification is performed based on the registration of the temporary drought counter.

  An example of a phenomenon corresponding to such a case will be described with reference to FIG. 6. First, in the first stage (see the upper part of FIG. 6), air accumulates in the upper part of the accumulation tank 44, and the heat medium liquid level in the accumulation tank 44. Falls below the low liquid level electrode 441, and the low liquid level electrode 441 enters the OFF output state, and as a second stage (see the lower part of the figure), it does not boil even when the standby time of the first timer 75 has elapsed. Therefore, the air is kept in the state where air is accumulated in the upper portion of the accumulation tank 44. In the case of such a phenomenon example, since there is a possibility that the amount of the heat medium is actually insufficient, error notification is performed.

  In the case of the above embodiment, even if the low liquid level electrode 441 is changed to the OFF output state, at least boiling at the heat collecting panel 2 without performing error notification of the insufficient amount of the heat medium simply by generating the OFF output. It waits for a time value at which (bubble generation) will occur, and during that time, it is determined whether or not the heat medium amount deficiency judging means 73 has truly deficient in the heat medium amount, and the low liquid level electrode 441 is still stable. An error notification is performed when the normal ON output state is not restored. For this reason, it is possible to avoid the occurrence of false detection / reporting about the shortage of the heat medium, but when it is determined that the shortage of the heat medium actually occurs, an error notification about the shortage of the heat medium is made accurately. You will be able to As a result, it is possible to reliably avoid the occurrence of misinformation and the occurrence of erroneous processing due to the misinformation.

<Other embodiments>
In addition, this invention is not limited to the said embodiment, Other various embodiment is included. That is, in the above embodiment, whether or not the heat medium temperature Ts detected by the heat collecting panel temperature sensor 21 as the determination process by the boiling condition establishment determination means 74 exceeds the boiling temperature Tf, or whether the circulation pump 41 The determination is made based on whether or not the stop continuation time exceeds the set time ts. However, the present invention is not limited to this. For example, an ambient temperature detection means such as an outside air temperature is provided, and the detected temperature will cause boiling. It may be determined that the boiling condition is satisfied when the temperature value is equal to or higher than the predicted temperature value. As such a temperature value, a temperature value (for example, 25 ° C. or more) when sunlight is irradiated on a clear day is set, and this temperature value is set a predetermined number of times (for example, 3) within a predetermined time of day. It is sufficient to determine that the boiling condition is satisfied when the occurrence of the above occurs.

  Moreover, although the heat exchanger 43 was installed in the hot water storage tank 3 in the above embodiment, the present invention is not limited to this, and the heat exchanger is installed outside the hot water storage tank 3 and is collected with respect to the heat exchanger. While the heat medium of the heat circulation circuit is circulated and supplied to the heat source side, the hot water in the hot water storage tank 3 is circulated and supplied to the heated side by another circulation pump, so that the hot water in the hot water storage tank is heat-exchanged and heated by the heat medium. A solar water heating system configured as described above is also included in the present invention.

2 Heat collection panel 3 Hot water storage tank 4 Heat collection circuit 21 Heat collection panel temperature sensor (heat medium temperature detection means)
41 Circulating pump 71 Remote control (notification means for outputting alarm)
73 Heat medium quantity shortage determining means 74 Boiling condition establishment determining means (bubble generation condition establishment determining means)
77 3rd timer (Timer that counts the stop duration of the circulation pump)
441 Low liquid level electrode (heat medium detection means)

Claims (3)

A heat collecting panel for collecting solar heat to heat the heat medium, a hot water storage tank, a heat exchanger for heat exchange heating of the hot water in the hot water storage tank, and the heat collecting panel and the heat exchange by operating a circulation pump A solar water heating system comprising a heat collection and circulation circuit that heat-exchanges and heats hot water in the hot water storage tank to store heat as hot water by circulating a heat medium between the tanks,
The heat medium detecting means for detecting and outputting the amount of the heat medium in the heat collecting circuit, and the amount of the heat medium is insufficient when the detection relating to the decrease in the amount of the heat medium is output by the heat medium detecting means. A heat medium amount shortage determining means for determining whether or not, and a bubble generation condition establishment determining means for determining whether or not an environmental condition in which bubbles can be generated in the heat collecting circuit is satisfied,
The heat medium amount shortage determining means determines that an environmental condition related to bubble generation is satisfied at least by the bubble generation condition establishment determining means after receiving an output related to detection of a decrease in the amount of heat medium from the heat medium detecting means. In the meantime, the output status from the heat medium detection means is monitored, and when the output related to the decrease detection is not resolved, it is determined that the heat medium amount is insufficient, and an alarm relating to the shortage of the heat medium is output. It is configured,
A solar water heating system characterized by that. The solar hot water system according to claim 1,
A heating medium temperature detecting means for detecting the temperature of the heating medium in the heat collecting panel or a temperature equivalent to this heating medium temperature;
The bubble generation condition establishment determining means is configured to determine that an environmental condition related to bubble generation is satisfied if the heating medium temperature detected by the heating medium temperature detection means is equal to or higher than a set temperature. Hot water system. The solar hot water system according to claim 1 or 2,
A timer for measuring a stop duration time that elapses in a state where the circulation pump is stopped,
The bubble generation condition establishment determining means is configured to determine that an environmental condition related to bubble generation is established if the elapsed stop time counted by the timer exceeds a set time value.

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