JP4046041B2 - Air intrusion judgment method for hot water heating system - Google Patents

Description

  The present invention provides a hot water heating system in which hot water is circulated through a circulation pipe between a heat source device and each heating terminal, and the air of the hot water heating system used for determining the occurrence of air intrusion from the circulation pipe. In particular, the present invention relates to a technique for determining the occurrence of air intrusion distinctly from the occurrence of water leakage.

  Conventionally, as a hot water heating system, a heat source device incorporating an open hot water tank and a circulation pump and a heating terminal (for example, a floor heating terminal) installed in each room or the like are connected by a circulation pipe, and the circulation pump is operated. After heating the hot water taken out from the hot water tank and supplying it to each heating terminal, the hot water after the heat radiation returned from each heating terminal to the hot water tank is heated again and supplied to each heating terminal. Things are generally known. The hot water tank is usually provided with an electrode rod for detecting the low water level and the high water level. When the water level in the hot water tank falls below the low water level due to evaporation or the like, water is automatically replenished from the outside to the high water level.

  In such a hot water heating system, since the circulation pipe is composed of an oxygen-permeable synthetic resin pipe such as a PE (polyethylene) pipe, the heating terminal is installed on the second or third floor (so-called floor). If it is installed at a position higher than the heat source machine installed on the first floor, such as the upper installation), the hot water in the circulation pipe extending to the floor tends to have a negative pressure in the heating operation stop (circulation pump stop) state As a result, oxygen may be absorbed from the outside through the wall of the circulation pipe, and air may enter the inside of the circulation pipe. When such air intrusion occurs, the water level of the hot water tank rises by the volume of the air that has intruded, resulting in overflow.

  As a technique for venting air that has entered such a circulation pipe, those described in Patent Document 1 or Patent Document 2 are known. The one described in Patent Document 1 introduces the air to the hot water tank by operating only the circulation pump to circulate the non-heated hot water every time the heating operation stop time elapses over a predetermined time, and from this hot water tank Control to escape to the external space is performed. In the device described in Patent Document 2, the circulation pump is operated to vent the air in the same manner as described above every time a predetermined time (for example, 720 hours) elapses regardless of whether the heating operation is performed or stopped.

  On the other hand, Patent Document 3 describes a technique for actually detecting air intrusion into a circulation pipe. That is, in the technique described in Patent Document 3, a part that bends upward is provided in the middle of the circulation pipe, and air that has entered the circulation pipe is gathered in this part, and the gathered air is directly collected by the air sensor. I try to detect it.

  Patent Document 4 describes a technique for avoiding inconvenience even if air intrusion occurs. That is, in the technique described in Patent Document 4, in addition to the two for the low water level and the high water level, two electrode rods for detecting each of the dangerous water level and the overflow water level are further provided. According to the state of the water level detection result by the electrode rod, the operation is switched to the heating operation after the operation of the circulation pump and the water replenishment are executed.

JP-A-6-109265 JP-A-11-108378 JP 2002-243178 A Japanese Patent Laid-Open No. 2002-250529

  By the way, in the hot water heating system described above, by monitoring the state of the above automatic water replenishment for the hot water tank, it is determined whether or not water leakage from the circulation pipe or the like has occurred. It is conceivable to perform a control for forcibly stopping the heating operation by outputting a water leakage error signal.

  For example, as shown in FIG. 4, when the heating pump is operated by turning on the heating switch to start the heating operation (step SA1), if the L electrode for detecting the low water level is turned off (the water level falls below the low water level). If it is burning, it is stopped, and it is determined whether 64 hours have passed since the last refilling (YES in step SA2, YES in step SA3, and steps SA4 and SA5). If the water level has fallen below the low water level even though 64 hours have not elapsed since the previous replenishment execution, one count is added to the counter M, and if this counter M is less than two, the water replenishment electromagnetic The valve is opened to start water replenishment (NO in step SA5, step S9, NO in step SA10, step SA6). If 64 hours have passed since the previous replenishment, it is determined that the water level has dropped due to natural decrease, and the refill electromagnetic valve is opened to replenish water (YES in step SA5, step SA6). If the H electrode for high water level detection does not turn on (the water level reaches the high water level) even after a predetermined time has elapsed after the start of this replenishment, a large amount of leakage will occur in any part of the water leakage so that replenishment cannot catch up. It determines with having generate | occur | produced, performs a process, such as outputting a water leak error signal, forcibly closing a water supplement electromagnetic valve, and stopping heating operation (step SA7 is NO, step SA12, SA13). On the other hand, if the H electrode is turned on instead, the water replenishing electromagnetic valve is closed and the process returns (YES in step SA7, step SA8). If the L electrode is turned off again 64 hours after the replenishment is performed (NO in steps SA1 to SA4 and step SA5), one more count is added to the counter M, resulting in a total of 2 or more. , It is determined that a small amount of leakage has occurred gradually in any part, and a leakage error signal is output to perform processing for leakage (for example, warning display and forced stop of heating operation) (YES in step SA10, Step SA11).

  On the other hand, if air intrusion occurs in the circulation pipe during the heating operation stop period as described above, when the heating operation is started next and hot water is circulated, the circulation flow causes the circulation pipe from the upper part to circulate. The internal air is returned to the hot water tank and released from the hot water tank to the atmosphere. Then, the water level in the hot water tank is lowered by the amount of air released to the atmosphere, and when the water level in the hot water tank falls below the low water level due to this drop, the above water replenishment process is started. When this water replenishment process is counted as the number of times of water replenishment and this is repeated, it is determined that water leakage has occurred as described above, and a water leakage error signal will be output. That is, even if water leakage does not occur, it is erroneously determined that water has leaked due to air intrusion, and as a result, safety processing such as forcibly stopping heating operation is performed and heating use becomes impossible. In such a case, the user will call a service person for inspection and repair based on a warning display etc., but even if the service person comes, no water leakage occurs, the cause is an automatic stop of unknown cause The result is a loss of confidence in the hot water heating system.

  For this reason, development of the technique which can distinguish and determine generation | occurrence | production of air invasion and generation | occurrence | production of water leakage will be requested | required. On the other hand, in the technique described in Patent Document 3, it is possible to grasp the occurrence of air intrusion by detecting the intruded air itself, but for this purpose, a special structure in which a part of the circulation pipe is bent. The formation of the portion and the installation of a sensor for detecting the air accumulated in the portion are newly required, which leads to complication of the hot water heating system and an increase in cost. In addition, since other patent documents 1, 2, and 4 cannot grasp the occurrence of air intrusion itself, the occurrence of the erroneous determination cannot be avoided. That is, in the technique described in Patent Document 1 or Patent Document 2 described above, it is assumed that air intrusion has occurred in the circulation pipe after a certain period of time regardless of whether air intrusion actually occurs. Therefore, since control for the air venting is performed, it is unclear whether or not air intrusion has occurred in the circulation pipe, and the occurrence of air intrusion cannot be grasped. In addition, the technique described in Patent Document 4 determines the water level in the hot water tank before starting the heating operation, and confirms that the water level in the hot water tank has become appropriate based on the determination result. Then, the operation is shifted to the heating operation, and the occurrence of air intrusion itself is not grasped by the determination. In other words, by dealing with all water level fluctuations based on factors other than water level fluctuations due to the occurrence of air intrusion, even if the current water level fluctuation is caused by air intrusion, This is to prevent the occurrence of inconvenience.

  The present invention has been made in view of such circumstances, and an object of the present invention is to make it possible to reliably determine the occurrence of air intrusion. It is an object of the present invention to provide an air intrusion determination method in a hot water heating system that can avoid the occurrence of an erroneous determination that a water leak has occurred.

  In order to achieve the above object, a heat source device having a hot water tank for storing circulating hot water and at least one heating terminal are connected by a circulation circuit, and the heated water heated from the heat source device through the circulation circuit is heated to the heating device. A water replenishing means configured to circulate and supply to the terminal and replenishing water to the hot water tank, a water level detecting means for detecting the water level in the hot water tank, and a water level in the hot water tank by the water level detecting means The water intrusion of the hot water heating system includes a water replenishment control means for performing water replenishment control for operating the water replenishing means and replenishing water to the set high water level in the warm water tank in response to detection that the water level is lower than the set low water level For the determination method, the following various inventions were completed.

  In the first invention, when a heating operation for circulating the hot water in the hot water tank with the heating terminal is started, the water level fluctuation in the hot water tank is monitored based on the water level detection information from the water level detecting means, It is determined that air intrusion has occurred in the circulation circuit when a water level drop exceeding the set water level difference is detected in the time lapse range of the initial stage of operation set for air intrusion determination from the start of operation (claim) Item 1).

  In the case of this first invention, when air intrusion occurs in the circulation circuit, the circulation circuit between the hot water tank and the heating terminal is sealed and filled with the circulating hot water, and the free water surface is formed in the hot water tank. The free water surface of the hot water tank will rise by the amount of air intrusion. When the heating operation is started in this state, the intruded air flows to the hot water tank together with the circulating hot water, and is released from the free water surface of the hot water tank. This opening will lower the water level in the hot water tank. Therefore, it is possible to determine that air intrusion has occurred by detecting a decrease in the water level in the hot water tank due to the release of the intruded air, that is, a decrease in the water level that is greater than the set water level difference based on the air intrusion.

  Here, “the time lapse range of the operation initial stage set for air intrusion determination from the start of the heating operation” described above is required until the circulation pump is operated and the combustion operation is started by turning on the heating switch or the like, for example. Each time connected to the heat source machine for the time or the time added to the time required to open the heat valve if a heat operated valve is installed in the circulation circuit from the heat source machine to the heating terminal It means the range until the total time has elapsed, including the time required for all of the intrusion air to flow through the circulation circuit with the heating terminal and be released from the hot water tank. The time required for the intrusion air to flow along with the circulating hot water in the circulation circuit and reach the hot water tank depends on the length of the circulation circuit to the heating terminal, the number of heating terminals, etc. What is necessary is just to set according to a condition. The above interpretation is the same in the following other inventions. The “set water level difference” may be determined based on the size of the hot water tank, the intrusion air amount assumed from the extension length or surface area of the so-called floor installation portion of the circulation circuit, and the like.

  In the second invention, when a heating operation for circulating the hot water in the hot water tank with the heating terminal is started, the water level fluctuation in the hot water tank is monitored based on the water level detection information from the water level detecting means, When the water level in the hot water tank that was higher than the set high water level before the start of operation is detected to be lower than the set low water level in the time lapse range of the initial operation stage set for air intrusion determination from the start of heating operation Therefore, it is determined that air intrusion occurs in the circulation circuit (claim 2).

  In the case of this second invention, when air intrusion occurs while the heating operation is stopped, the water level in the hot water tank rises as described above, and when the heating operation is started, the water level in the hot water tank decreases due to the release of the intruding air. Will do. In these cases, if the water level in the hot water tank rises by exceeding the set high water level due to the rise in the water level due to the above air intrusion, the amount of hot water in the circulation circuit decreases by the amount of the overflow. The lowering of the water level is lower than the set low water level, that is, the water replenishment control is started. In other words, the occurrence of the situation where the water replenishment control is started due to the intrusion of air means that the amount of hot water has decreased due to the overflow, and the fact that the overflow has occurred The rise should have already detected that the set high water level has been exceeded before the start of heating operation. And the start of the supplemental water control means that the water in the hot water tank has fallen below the set low water level, which is the start condition of the supplemental water control, due to the start of the heating operation, and when the water level becomes less than the set low water level. The water level should be detected. Therefore, from the state where the water level higher than the set high water level was detected before the heating operation started, the intrusion air after the heating operation started was released from the hot water tank, so that a water level drop below the set low water level was detected. It is possible to reliably determine that air intrusion has occurred. In short, the second aspect of the invention specifies a more reliable one of the specific forms of “water level lowering more than the set water level difference” in the first aspect of the invention.

  In the case of the third invention, when the heating operation for circulating the hot water in the hot water tank to and from the heating terminal is started, the execution status of the water replenishment control by the water replenishing control means is monitored, and the air intrusion determination is made from the start of the heating operation. It is determined that air intrusion has occurred in the circulation circuit when the start of execution of the water replenishment control more than the set number of times in the time lapse range of the initial stage of operation set for (Claim 3).

  In the case of this third invention, as a result of the intrusion of air as described above and the hot water in the hot water tank overflowing, when the heating operation is started, the water level is reduced to below the set low water level and the execution of the water supplement control is started. Therefore, it can be determined that air intrusion has occurred when the start of execution of such water replenishment control is greater than or equal to the set number of times in the time lapse range of the initial stage of operation. Here, the above-mentioned “execution start set number” may be set once or twice or more. This is because the influence on the water level fluctuation of the hot water tank varies depending on the amount of air intrusion itself or the circulation flow rate of the hot water circulation that causes the intrusion air to flow. In other words, if intrusion air continues to reach the hot water tank, replenishment control itself will not be completed until the set high water level even if replenishment control is started. This is because when the water reaches the hot water tank intermittently, even if the supplementary water control is started once and terminated, the water level is lowered again and the supplemental water control may be started.

  In any of the first to third inventions described above, the following specific items may be further added. That is, first, when two or more heating terminals are connected to the heat source device by individual circulation circuits, whether or not air intrusion occurs is determined every time the heating operation of each heating terminal is started ( Claim 4). When the hot water heating system is configured with two or more heating terminals, not all the heating terminals start heating operation at the same time, and only one heating terminal is used according to the use situation of the user. Heating operation may be started. For this reason, it is possible to accurately determine the air intrusion of the entire system by determining whether or not there is air intrusion for each circulation circuit of each heating terminal.

  Second, the execution status of the water replenishment control by the water replenishment control means is monitored, the number of times of water replenishment executed within the set time is counted, and when the number of times of water replenishment exceeds the set number of times, it is determined that leakage has occurred. On the other hand, even if the water replenishment control by the water replenishment control means is executed in the time lapse range of the initial stage of operation set for the air intrusion determination from the start of the heating operation, it is excluded from the count as the number of water replenishment for the water leakage determination. (Claim 5). In other words, when determining whether or not water leakage has occurred based on the number of times of water replenishment (leakage determination), the number of times of water replenishment performed in the time lapse range of the initial stage of operation is not counted as the number of times of water replenishment for water leakage determination It is. As a result, it is possible to reliably avoid the occurrence of erroneous determination of water leakage when the water replenishment control due to air intrusion is counted as the number of times of water replenishment for water leakage determination. In short, it is possible to avoid the occurrence of erroneous determination due to air intrusion in water leakage determination by distinguishing between execution of water replenishment control and that due to air intrusion and that due to water leakage.

  As described above, according to the air intrusion determination method of the hot water heating system according to any one of claims 1 to 5, whether or not air intrusion has occurred in the circulation circuit extending to the heating terminal during the heating operation stop. Such a determination can be made with certainty. That is, according to claim 1, due to the occurrence of a drop in the water level in the hot water tank that is greater than the set water level difference, according to claim 2, from the water level detection state that is higher than the set high water level to the detection of the set low water level by starting the heating operation According to the third aspect of the present invention, the occurrence of air intrusion can be determined by starting the execution of water replenishment control in a predetermined time lapse range of the heating operation. As a result of reliably determining whether or not air intrusion has occurred, it is possible to reliably determine whether or not water leakage has occurred based on a decrease in the water level of the hot water tank.

  In particular, according to claim 4, when the hot water heating system is configured with two or more heating terminals, the determination of the presence or absence of air intrusion is also performed for each circulation circuit of each heating terminal. This makes it possible to accurately determine the air intrusion of the entire system.

  According to claim 5, when determining whether or not water leakage has occurred based on the number of times of water replenishment, the number of times of water replenishment executed in the time lapse range of the initial stage of operation is not counted as the number of times of water replenishment in the water leakage determination. By doing so, it is possible to distinguish between the occurrence of air intrusion and the occurrence of water leakage, and an erroneous determination that water leakage has occurred despite the drop in water level due to air intrusion occurs. The possibility can be reliably avoided.

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

  FIG. 1 shows a hot water heating system in which an embodiment of the present invention is implemented. 2 is a heat source unit installed on, for example, the first floor of a building, 4 is on the second or third floor above the heat source unit 2, for example. A so-called floor-mounted heating terminal installed, 5 is a heating terminal installed on the same floor as the heat source unit 2, and 6 is a controller.

  The heat source unit 2 has an open-type hot water tank 21 in which a return path 20 communicates with the bottom and stores hot water for circulation (hereinafter referred to as “hot water”), and hot water in the hot water tank 21 is taken out and pumped through the path 22. Circulating heat pump 23, a heat exchanger 25 for heat exchange heating by the combustion heat of the combustion burner 24 while hot water pumped by the circulation pump 23 passes, and hot water heated by the heat exchanger 25 are supplied. A forward passage 26 and a water replenishing passage 28 for replenishing the warm water tank 21 from the outside via a water replenishing electromagnetic valve 27 are provided. The upstream end of the replenishing water passage 28 is connected to an external tap water supply pipe or the like, and the replenishing electromagnetic valve 27 is opened to replenish water to the hot water tank 21 based on the water pressure or the like. The water replenishment means is constituted by the water replenishment path 28 and the water replenishment electromagnetic valve 27.

  The hot water tank 21 is provided with a rod-shaped electrode (H electrode) 29 for detecting a set high water level and a rod-shaped electrode (L electrode) 30 for detecting a set low water level. The H electrode 29 or the L electrode 30 outputs an ON signal to the controller 6 when hot water is in contact, and outputs an OFF signal when the hot water becomes non-contact, and an ON signal is output. If the water level is changed from ON to OFF, it is detected that the water level in the hot water tank 21 is lower than the predetermined water level. These H electrode 29 and L electrode 30 constitute water level detection means. At the start of use of the hot water heating system, the replenishing electromagnetic valve 27 is opened until water is filled in each circulation circuit and the hot water tank 21, which will be described later, until the H electrode 29 changes from OFF to ON in the hot water tank 21. That is, use is started in a state where water is filled up to the set high water level.

  Further, a forward connection head 31 having a predetermined number of branch ports is connected to the downstream end of the forward path 26 of the heat source unit 2, and a return connection having a predetermined number of branch ports is connected to the upstream end of the return path 20. The head 32 is connected. The upstream ends of the forward pipe 41 for the heating terminal 4 and the forward pipe 51 for the heating terminal 5 are individually connected to the forward connection head 31, and the return pipes 42 and 52 from the heating terminal 4 or 5 are individually connected to the above. It is connected to the return connection head 32. Each branch port of the forward connection head 31 is provided with a thermal valve for opening and closing (not shown). For example, when the heating operation of the heating terminal 4 installed on the floor is started, a command signal from the controller 6 is used. The corresponding thermal valve is opened, and the hot water heated from the outgoing path 26 to the outgoing pipe 41 is circulated and supplied. And the hot water after radiating heat in the heating terminal 4 is returned to the hot water tank 21 through the return pipe 42, the connection head 32, and the return path 20. Accordingly, the return connection head 32, the return path 20, the take-out path 22, the forward path 26, and the forward connection head 31 are shared, and the circulation line of the heating terminal 4 is configured by the forward piping 41 and the return piping 42. And the return pipe 52 constitutes a circulation circuit of the heating terminal 5. In other words, an independent system circulation circuit is formed for each heating terminal 4 and 5, and the forward piping 41 and 51 and the return piping 42 and 52 have oxygen permeability and may intrude air from the outside. It is composed of (polyethylene) piping.

  The heating terminals 4 and 5 are configured by various types such as a floor heating terminal, a fan convector, or a bathroom dryer. In this embodiment, the heating terminals 4 and 5 are both configured by a floor heating terminal.

  The controller 6 is constituted by a microcomputer having an MPU or the like, and heating operation control, replenishment control or the like based on an operation command or the like input by a user to remote controllers 40 and 50 provided in association with the heating terminals 4 and 5. Various controls and processing such as abnormality determination processing are performed. Specifically, as shown in FIG. 2, the controller 6 determines whether or not air heating has occurred and whether or not water leakage has occurred, and the heating operation control unit 61 and the water replenishment control unit 62 as water replenishment control means. And an abnormality determination processing unit 63 that performs processing for the above.

  When the user turns on the heating switch of the remote controller 40, for example, the heating operation control unit 61 receives the output of the ON command signal and starts the heating operation of the heating terminal 4. First, after operating the circulation pump 23, the combustion burner 24 is burned. Then, the corresponding thermal valve of the forward connection head 31 is opened. Until this thermal valve is opened, the heat source machine 2 is circulated from the forward path 26 to the return path 20 through a bypass path (not shown). When the thermal valve is opened, the hot water in the hot water tank 21 is sent to the heat exchanger 25 through the take-out path 22, and the heated hot water is heated through the outgoing path 26, the outgoing connection head 31 and the outgoing pipe 41. The hot water that has been sent to the terminal 4 and radiated from the heating terminal 4 is returned to the hot water tank 21 through the return pipe 42, the return connection head 32, and the return path 20, and such hot water circulation is repeated. .

  In order to cope with a decrease in the amount of hot water due to natural evaporation or the like from the hot water tank 21, the water replenishment control unit 62 attempts to replenish water by water replenishment control when the water level in the hot water tank 21 decreases. Specifically, if the L electrode 30 changes from ON to OFF, that is, if the water level in the hot water tank 21 falls below a set low water level, the supplementary electromagnetic valve 27 is opened in response to the detection signal. The operation control is performed to replenish water into the hot water tank from the water replenishment path 28, and this water replenishment is continued until the H electrode 29 changes from OFF to ON, that is, until the water level in the hot water tank 21 becomes equal to or higher than the set high water level. In response to the ON signal output of 29, the replenishing electromagnetic valve 27 is controlled to be closed and the replenishment is finished. In addition, when the execution of such water replenishment control is started, a signal to that effect is output to the abnormality determination processing unit 63.

  The abnormality determination processing unit 63 is started by a counter L for determining whether or not air intrusion has occurred, a counter N for determining whether or not water leakage (small amount of leakage) has occurred, and heating operation start. A timer for measuring the elapsed time from the start of the heating operation and a timer for measuring the elapsed time from the previous replenishment by starting after execution of the previous replenishment control, the ON / OFF change of the L electrode 30 and the H electrode 29 Based on the water level fluctuation information due to the OFF / ON change, it is determined whether or not air intrusion has occurred (air intrusion determination) and whether or not water leakage has occurred (leakage determination). Various correspondence processes are performed. In addition, the above-mentioned water leak determination is divided into two types, a small amount leak determination whether or not a small amount of water leaks gradually and a large amount leak determination whether or not a large amount of water leaks at a time. It is like that.

  In addition, the abnormality determination processing unit 63 is preset with two types of time values, a set time value for air intrusion determination and a set time value for water leakage determination. Specifically, a set time value for water leakage determination Is divided into a set time value for determining a small amount of leak (for example, 64 hours from the previous replenishment) and a set time value for determining a large amount of leak (for example, 2 minutes from the start of the current replenishment). The set time value for air intrusion determination is a time value that defines the time lapse range in the initial stage of operation set for air intrusion determination from the start of heating operation, and the various elements 23 and 24 for starting the heating operation include If the operation is started and air has entered from the circulation circuit of the heating terminal subject to heating operation, the time value (for example, 10 minutes) at which all of the intruding air will reach the hot water tank 21 together with the hot water circulation flow is obtained. Is set.

  Next, various controls and processes performed by the heating operation control unit 61, the water replenishment control unit 62, and the abnormality determination processing unit 63 will be described with reference to the flowchart of FIG.

  First, when the heating switch of the remote controller 40 and / or 50 is turned ON, the heating operation control is started by the heating operation control unit 41 (step S1). The contents of this heating operation control are as described above. In this heating operation start stage, except when the operation stop state continues for a long period of time so that the water level itself decreases due to natural evaporation from the inside of the hot water tank 21 since the end of the previous heating operation use, The water level up to the set high water level is maintained in the hot water tank 21 by the previous control, and the H electrode 29 is in the ON state. In addition, even if it is left in an operation stop state for an exceptionally long period of time, it is a condition for starting the heating operation that there is at least a water level higher than the set low water level and the L electrode 30 is in the ON state. And heating operation is continued as long as the L electrode 30 maintains an ON state (it is NO at step S2, step S1).

  However, if the L electrode 30 changes from ON to OFF after the heating operation is started (YES in step S2), if the combustion burner 24 is not combusting at that time (NO in step S3), the combustion burner 24 is in the combustion state. If this is the case, the combustion is stopped and post-circulation is performed for a predetermined short time (for example, 20 seconds) (YES in step S3, step S4), and the change (setting) of the L electrode 30 is set based on the timer timing. It is checked whether or not the water level change from the top to the bottom of the low water level is within a set time (for example, 10 minutes) for air intrusion determination from the start of the heating operation (step S5).

  When the change of the L electrode 30 occurs within the set time range (NO in step S5), the counter L is counted once (step S10), and the counter L should be counted twice or more. If it is determined that the water has fallen due to air intrusion (decrease in water level) and waterfall treatment is reserved (YES in step S11, step S12), if the counter L is less than twice, the water replenishing electromagnetic valve 27 in step S7 Proceed to open operation. In the above-described water falling treatment, the heating operation is stopped and only the circulation pump 23 is operated for a predetermined time to circulate the hot water, whereby all the intruding air in the circulation circuit is released from the hot water tank 21 and discharged. When the counter L is less than two times, that is, once, the heating operation is resumed after replenishing with water replenishment control after step S7, and still within the set time range for air intrusion determination described above. When the L electrode 30 changes from ON to OFF and the counter L becomes twice, the above-described water falling treatment is performed. In other words, the first time is allowed, but if it occurs twice, it is determined that air intrusion has surely occurred and the falling water treatment is performed.

  If the set time range for air intrusion determination has already passed in step S5 (YES in step S5), it is confirmed whether or not a set time for water leak determination (for example, 64 hours) has elapsed since the previous water refill ( Step S6). If it has already passed, it will transfer to the water supplement control of step S7 immediately (it is YES at step S6). If the counter N has not yet elapsed, the counter N is counted once (NO in step S6, step S13). If the count of the counter N is two or more, it is determined that the water level is lowered due to a small amount of leakage. On the other hand, the small leakage process is performed (YES in step S14, step S15), and if the counter N is less than twice, the operation proceeds to the opening operation of the water supplement electromagnetic valve 27 in step S7 (NO in step S14). The small amount leakage process described above stops the heating operation and notifies the user that a small amount of leakage has occurred. This notification may be displayed on the remote control 40, 50, etc., with a text saying “A small amount of leak has occurred. Please contact a service person”, an error code number indicating this, or Together with these, a warning light is turned on or blinked. When the count of the counter N is less than 2, that is, once, the heating operation is restarted after replenishing with water replenishment control after step S7, and still the set time range for air intrusion determination (10 Min)), but if the counter electrode N reaches twice again after the L electrode 30 changes from ON to OFF before the set time (64 hours) for determining water leakage elapses, the above small amount Perform leak processing. That is, the lowering of the water level from ON to OFF of the L electrode 30 occurring within the set time range for air intrusion determination does not count, the set time for air intrusion determination elapses and the set time for water leak determination is reached. If the generated water level drop from the ON to OFF of the L electrode 30 occurs twice, it is determined that a small amount of leakage has occurred.

  In step S7, the water replenishing electromagnetic valve 27 is opened, water is replenished into the hot water tank 21 from the water replenishing passage 28, and the water replenishing electromagnetic valve 27 is closed when the H electrode 29 changes from OFF to ON (in step S8). YES, step S9). These steps S7 to S9 are the contents of the water replenishment control. At this time, in spite of starting the water replenishment by opening the water replenishing electromagnetic valve 27 in step S7, the set time (set as a time value that would normally be able to be filled up to the set high water level) For example, if the H electrode 29 still does not change to ON even after continuing for 2 minutes, it is determined that a large amount of leakage has occurred, and the water replenishing solenoid valve is closed (NO in step S8, step S16). ), A large leakage process is performed (step S17). That is, the user is notified through the remote controllers 40 and 50 in the same manner as the above-described small leak processing, while the processing for shutting down the operation of the circulation pump 23 and the closing operation of the thermal valve is immediately performed.

  According to the abnormality determination process described above, when the heating operation is started, that is, when the water level of the hot water tank 21 is decreased to be lower than the set low water level due to the start of the hot water circulation, it is detected by a change from ON to OFF of the L electrode 30. In addition, since it is distinguished whether it is for air intrusion determination or for water leak determination depending on when the phenomenon of the water level drop detection occurs, it becomes possible to distinguish between the occurrence of air intrusion and the occurrence of water leak. . In other words, if it is within the set time lapse range for air intrusion determination in the initial stage of operation from the start of heating operation, it is counted by the counter L for air intrusion determination, while the set time has elapsed since the previous replenishment after the set time has elapsed. If it is within the range, the counter N for determining a small amount of leak is counted, that is, the above-described drop in the water level occurring within the set time lapse range for determining air intrusion is not counted for determining the leak. Thus, it is possible to reliably distinguish and determine whether the occurrence of the above phenomenon is caused by the occurrence of air intrusion or the occurrence of water leakage. As a result, it is possible to reliably determine the occurrence of air intrusion, while reliably avoiding erroneous determination of occurrence of water leakage based on a drop in the water level caused by the occurrence of air intrusion.

<Other embodiments>
In addition, this invention is not limited to the said embodiment, Various other embodiments are included. That is, in the above embodiment, the hot water heating system having a basic configuration in which one heating terminal installed on the floor is installed is described as an example. However, two or more heating terminals installed on the floor are installed, and these two or more heating terminals are installed. A hot water heating system may be configured by connecting a terminal to the heat source unit 2 by an individual circulation circuit. In this case, what is necessary is just to perform the determination about whether the air invasion of the said embodiment generate | occur | produced for every heating operation start of each heating terminal.

  In the above embodiment, the combination of the H electrode 29 and the L electrode 30 is used as the water level detection means. However, for example, a float-attached water level sensor that moves along with the fluctuation of the water level and continuously detects the water level is used as the water level detection means. You may do it.

  Although the case where the heat source unit 2 is installed in the first floor portion is shown in the above embodiment, the present invention is not limited thereto, and the heat source unit is installed in a hot water heating system in which the heat source unit is installed lower than one heating terminal in the vertical direction. The present invention can be applied.

  Moreover, in the said embodiment, the water level fall from the state which detected the water level more than a setting high water level before the heating operation start (H electrode is ON state) to less than a setting low water level by the heating operation start (water level more than a setting water level difference or more) Is detected (the L electrode changes from ON to OFF), it is determined that air intrusion has occurred (the counter for air intrusion determination is incremented by 1). If there is, it can be determined that air intrusion will surely occur. Not limited to this, regardless of the water level state before the start of heating operation, the set low water level is changed from above to below. Air intrusion occurs when a drop in water level is detected (L electrode changes from ON to OFF), or when a drop in water level from the top to the set high water level is detected (H electrode changes from ON to OFF) It is determined that Details, may be the counter for determining the air entering the plus one.

  Furthermore, in the above-described embodiment, water such as tap water supplemented by the water replenishing means is used as the hot water, but not limited to this, a liquid heat medium other than tap water is also included in the “hot water”.

It is a mimetic diagram of a hot water heating system to which an embodiment of the present invention is applied. It is a block diagram which shows the content of a controller. It is a flowchart which shows the control content by a controller. It is a flowchart which shows the control content considered in order to demonstrate a subject.

Explanation of symbols

2 Heat source machines 4, 5 Heating terminal 20 Return path (circulation circuit)
21 Hot water tank 22 Extraction path (circulation circuit)
26 Outbound (circulation circuit)
27 Water refill solenoid valve (water replenishment means)
28 Water replenishment channel (water replenishment means)
29 H electrode (water level detection means)
30 L electrode (water level detection means)
41, 51 Outward piping (circulation circuit)
42,52 Return piping (circulation circuit)
62 Water replenishment control unit (water replenishment control means)
63 Abnormality determination processing unit

Claims (5)

A heat source device having a hot water tank for storing circulating hot water and at least one heating terminal are connected by a circulation circuit, and the hot water heated from the heat source device is circulated and supplied to the heating terminal through the circulation circuit. And a water replenishing means for supplying water to the hot water tank, a water level detecting means for detecting the water level in the hot water tank, and the water level in the hot water tank lower than a set low water level by the water level detecting means. An air intrusion determination method for a hot water heating system, comprising: a water replenishment control means for operating the water replenishing means in response to the detection of this and performing water replenishment control for replenishing water in the warm water tank to a set high water level,
When heating operation to circulate hot water in the hot water tank with the heating terminal is started, water level fluctuation in the hot water tank is monitored based on the water level detection information from the water level detection means, and air intrusion determination is made from the start of heating operation A hot water heating system characterized by determining that air intrusion has occurred in the circulation circuit when a drop in water level exceeding a set water level difference is detected in a time lapse range set in an initial stage of operation. Air intrusion detection method. A heat source device having a hot water tank for storing circulating hot water and at least one heating terminal are connected by a circulation circuit, and the hot water heated from the heat source device is circulated and supplied to the heating terminal through the circulation circuit. And a water replenishing means for supplying water to the hot water tank, a water level detecting means for detecting the water level in the hot water tank, and the water level in the hot water tank lower than a set low water level by the water level detecting means. An air intrusion determination method for a hot water heating system, comprising: a water replenishment control means for operating the water replenishing means in response to the detection of this and performing water replenishment control for replenishing water in the warm water tank to a set high water level,
When heating operation is started to circulate hot water in the hot water tank with the heating terminal, the water level fluctuation in the hot water tank is monitored based on the water level detection information from the water level detection means, and the set level is set before the heating operation is started. When the water level in the hot water tank that was above the water level is detected to fall below the set low water level in the time lapse range of the initial stage of operation set for air intrusion determination from the start of heating operation, An air intrusion determination method for a hot water heating system, characterized in that it is determined that air intrusion has occurred. A heat source device having a hot water tank for storing circulating hot water and at least one heating terminal are connected by a circulation circuit, and the hot water heated from the heat source device is circulated and supplied to the heating terminal through the circulation circuit. And a water replenishing means for supplying water to the hot water tank, a water level detecting means for detecting the water level in the hot water tank, and the water level in the hot water tank lower than a set low water level by the water level detecting means. An air intrusion determination method for a hot water heating system, comprising: a water replenishment control means for operating the water replenishing means in response to the detection of this and performing water replenishment control for replenishing water in the warm water tank to a set high water level,
When the heating operation for circulating the hot water in the hot water tank to and from the heating terminal is started, the execution status of the water replenishment control by the water replenishing control means is monitored, and the initial operation set for air intrusion determination from the start of the heating operation An air intrusion determination method for a hot water heating system, characterized in that it is determined that air intrusion has occurred in the circulation circuit when the start of execution of water replenishment control more than a set number of times in the time lapse range of the stage. An air intrusion determination method for a hot water heating system according to any one of claims 1 to 3,
When two or more heating terminals are connected to the heat source unit by individual circulation circuits, the presence or absence of air intrusion is determined each time the heating operation of each heating terminal is started. Air intrusion method. An air intrusion determination method for a hot water heating system according to any one of claims 1 to 3,
The execution status of the water replenishment control by the water replenishment control means is monitored and the number of times of water replenishment executed within a set time is counted. When the number of times of water replenishment exceeds the set number of times, it is determined that water leakage has occurred. The hot water heating is configured so that even if the water replenishment control by the water replenishment control means is executed in the time lapse range of the initial stage of operation set for air intrusion determination from the start of operation, it is excluded from the count as the water replenishment frequency for the water leakage determination. System air intrusion detection method.

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