JP4159047B2 - Connected water heater - Google Patents

Description

  The present invention relates to a connected hot water supply apparatus in which two or more hot water heaters are installed in parallel to a water supply path and a hot water supply path so that the number of hot water heaters to be burned according to a hot water supply request is changed. The present invention relates to a technique capable of preventing a decrease in hot water supply temperature and enabling hot water supply at a set hot water temperature as much as possible even when a failure occurs in the water heater.

  2. Description of the Related Art Conventionally, a connected hot water supply apparatus is known in which two or more hot water heaters are connected in parallel between a water supply path and a hot water supply path. In this apparatus, switching of the number of combustions to determine which hot water heater is burned is performed by switching of water flow or water flow shut-off by switching the open / close valve (for example, see Patent Document 1).

JP-A-6-281248

By the way, in the conventional connected hot water supply apparatus, in order to reduce costs, the installation of an on-off valve (for example, an electromagnetic on-off valve) only for switching between water flow or water cut-off is omitted, instead of this, All can body flow control valves (also called water volume servo valves, overflow prevention valves, etc.) that water heaters originally have, and bypass flow control valves (also called mixed water amount adjustment valves) in addition to these can body flow control valves adding閉切conversion function is considered possible to perform the switching of the water flow or water flow blocked by these. In addition to the controller provided for each water heater, a system controller is provided for comprehensively controlling the controllers of each water heater, and whether or not combustion is performed based on a control command from the system controller and the combustion By switching between water flow and water flow cut-off for enabling, the number of combustion units (number control) according to the hot water supply request is performed in the connected hot water supply device.

  However, when such a technique is adopted, the following problems may be caused due to the occurrence of a failure (abnormality of impossible to switch fully closed) of the can body flow control valve and / or the bypass flow control valve.

  That is, for example, in the connected hot water supply apparatus shown in FIG. 1, during the hot water supply standby in which the hot water tap 51 is closed, the can body flow rate control valve 232 of any one of the hot water heaters (for example, 2a) is opened and the other hot water heaters are opened. While the can flow rate control valve 232 and the bypass flow rate control valve 242 of 2b to 2d are both fully closed, the hot water heater 2a is burned when hot water is used, and a second hot water heater ( For example, the can flow control valve 232 and the bypass flow control valve 242 of 2b) are opened and burned. In this case, the second hot water heater 2b from the system controller 6 is brought into a hot water supply standby state (combustion stopped and the can body flow rate control valve 232 and the bypass flow rate control valve 242 are fully closed and switched) as the hot water supply request is lowered. Even if a control signal is transmitted, for example, if an open failure occurs in which the can body flow control valve 232 cannot be fully closed due to foreign matter biting or the like and remains open, water from the water supply path 4 is supplied with the hot water supply. As a result, the hot water supply temperature to the hot-water tap 51 decreases. Even if the can body flow control valve 232 is normally fully closed, if the above open abnormality occurs in the bypass flow control valve 242, the hot water supply temperature is lowered as described above. As a result, there arises a disadvantage that hot water supply at the set hot water supply temperature cannot be performed.

  In addition, unlike the example of FIG. 1 described above, when the can body flow control valve is disposed on the downstream side of the merging position of the bypass passage, only the fully closed switching function is added to the can body flow control valve. In this case as well, inconvenience similar to the above occurs due to the occurrence of abnormal opening of the can flow control valve.

  The present invention has been made in view of such circumstances, and the object of the present invention is to eliminate the provision of a dedicated on-off valve and to pass water such as a can body flow control valve originally provided in a water heater. When a flow control valve is used to switch between water flow and water flow shutoff, even if a failure occurs in the water flow control valve, a connected hot water supply device that can enable hot water supply at the set hot water temperature is provided. It is to provide.

The following reference technique can be considered as a prerequisite technique of the present invention for achieving the above object . That is , a system controller that controls the number of two or more water heaters that are interposed in parallel between a water supply path and a hot water supply path, and the number of water heaters that burn with all these water heaters as control targets A water flow rate control valve having a water flow rate adjusting function and a fully closed switching function in the water flow channel of each water heater, and a water flow rate detecting means for detecting the water flow rate passing through the water flow channel. Is provided, and the water flow control valve is configured to be fully closed and switched based on a control command from the system controller. It was decided.

That is, in the reference technique 1 , when the occurrence of a failure that disables at least the switching operation from open to fully closed is detected in the water flow rate control valve in any of the hot water heaters, the failure is detected. The specific water heater in which the occurrence of water is detected is separated from the control target of the number control by the system controller, while the specific water heater is configured to execute independent hot water control independently.

In the case of this reference technique 1 , when a failure that prevents the switching operation from open to fully closed in any water heater flow rate control valve, that is, occurrence of an open failure, is detected, the open failure detection output is received. In the system controller, the specific water heater in which the occurrence of an open failure is detected is separated from the unit control, and the number control is performed by the remaining number of water heaters. In the specific water heater, control from the system controller is performed. Without receiving it, the unique hot water supply control is executed independently. As a result, when the above-mentioned specific hot water heater is maintained as an object of unit control with an open failure, even if the hot water tap is opened even if it is removed from the number of combustion units and the hot water supply is not used, It is possible to prevent the occurrence of a situation in which the temperature of the hot water supply decreases as water from the water supply path flows out to the hot water supply path through the control valve.

In the reference technique 2 , each water heater is detected by a failure detecting means for detecting the occurrence of a failure in which at least the switching operation from the open to the fully closed state is impossible in the water flow control valve, and a failure is detected from the failure detecting means. When the generation detection output is received, the system controller is provided with a unique control means for executing a unique hot water supply control by separating from the control target by the system controller, and the failure detection means outputs the failure detection output from the system controller. The specific water heater that sent out the detection output when it was received is separated from the control target of the number control by the system controller.

In this reference technique 2, so that one configuration example for implementing the reference technique 1 is specifically identified. That is, since each water heater that constitutes the connected hot water supply apparatus includes failure detection means and unique control means, it is impossible to switch the flow rate control valve from open to fully closed in any of the water heaters. When the failure detection means detects the occurrence of a failure (open failure), the system controller receives the open failure detection output, and the system controller disconnects the specific hot water heater in which the occurrence of the open failure is detected from the unit control and the remaining number The number control is performed by the hot water heater, and the hot water heater in which the occurrence of the failure is detected does not receive control from the system controller, and the unique hot water control by the unique control means is executed alone. Thereby, like the reference technique 1 , even if it removes from the number of combustion and makes it a hot water supply non-use state, when the said specific water heater is made into the control object of unit control with an open failure and it continues, a hot-water tap is opened. In addition, it is possible to prevent the occurrence of a situation in which the temperature of the hot water supply decreases as water from the water supply path flows into the hot water supply path through the open failure flow rate control valve.

In the connected hot water supply apparatus of the above reference technique 1 or reference technique 2 , as the above unique hot water supply control, when the water flow rate exceeding the minimum operating flow rate is detected by the water flow rate detecting means, the combustion operation is performed independently. it is Ru can be. As a result, even if an open failure occurs in the water flow control valve and the system controller is disconnected from the unit control, if water flows from the water supply path due to the open failure, the combustion is activated by the original control and heating is performed. Since the subsequent hot water is discharged into the hot water supply path, the occurrence of a situation where the hot water supply temperature to the hot-water tap decreases is more reliably realized. In this case, as the own hot water supply control, Ru can be configured to tapping temperature to the hot water supply path to the combustion operation to be the set hot water supply temperature by adjusting the combustion amount in accordance with the detection value of the water flow rate. By doing in this way, since the hot water temperature discharged from the hot water heater in which an open failure has occurred to the hot water supply path is controlled to the set hot water temperature, not only the occurrence of a decrease in the hot water temperature is prevented, but either Even if an open failure occurs in the water heater, it is possible to maintain hot water supply at the set hot water temperature.

In this invention, it specified about the case where it applied to the connection type hot water supply apparatus of the structure which actualized the technique which concerns on the above reference technique 1 or the reference technique 2 more.

The invention according to claim 1 or claim 3 has the following premise configuration. That is , a system controller that controls the number of two or more water heaters that are interposed in parallel between a water supply path and a hot water supply path, and the number of water heaters that burn with all these water heaters as control targets Shall be provided. And as each said hot-water supply device, bypassing the said heat exchanger, the hot water path connected to the said water supply path, the hot water path which makes the hot water into the hot water path through the heat exchanger for heating, and bypassing the said heat exchanger A bypass passage that mixes the incoming water from the incoming water passage with the hot water of the outgoing water passage; a bypass flow control valve that is interposed in the bypass passage and has a function of adjusting the water flow rate and a fully closed switching function; and A can body flow control valve having a function of adjusting the flow rate of water flow and a function of fully closing switching, which is interposed on a path from the branching position to the inlet water path to the hot water outlet of the joining position of the bypass path through the heat exchanger; One of the bypass flow sensor for detecting the water flow rate passing through the bypass passage, the can flow sensor for detecting the water flow rate passing through the heat exchanger, and the bypass flow control valve and the can flow control valve Little In both cases, a failure detection means that detects and outputs the occurrence of a failure that disables the switching operation from open to fully closed, and when the failure detection detection output is received from this failure detection means, the system controller leaves the controlled object. And a failure time control means for executing the original hot water supply control. Further, as the system controller, a water heater that dispatched the detection output upon receiving a detection output of the open failure occurs from said failure detecting means configured to separate from the target of the operation control by the system controller (claim 1 or claim Item 3 ).

In the case of the premise structure of claim 1 or claim 3, each water heater constituting the connected hot water supply apparatus has the above-described structure, and the can flow control valve and / or the bypass flow control valve of any one of the water heaters. even as the open failure occurs, so that the hot water temperature to be hot water in the hot-water tap from hot water supply path can prevent occurrence of a situation to decrease. That is, in a water heater assigned as a hot water heater not used (combustion prohibited) by controlling the number of units by the system controller, a full-close switching command is output to both the bypass flow control valve and the can flow control valve. If each control valve is switched normally in response to this full-close switching command, the communication between the water supply path and the hot water supply path is interrupted, but if the full-close switching operation becomes abnormal and an open failure occurs, For example, if the above-mentioned open failure occurs in the bypass flow rate control valve, water from the water supply route flows through the bypass channel to the hot water supply route, and if an open failure occurs in the can flow control valve Water from the water supply path flows into the hot water supply path through the water channel, the heat exchanger, and the hot water supply channel. In the present invention, when such an open failure occurs, the occurrence of the open failure is detected by the failure detection means, and the system controller that has received the detection output receives the detected hot water heater from the operation control target. On the other hand, the hot water heater in which the failure has occurred performs independent hot water control by the control means at the time of failure. For this reason, even if an open failure occurs, it is possible to prevent the occurrence of a situation in which the temperature of the hot water supplied to the hot water tap through the hot water supply path decreases due to the mixing of water that flows in the non-combustion state. become.

Then the linked water heater according to claim 1 in addition to the assumptions above configuration, as the failure control means in the premise construction, when subjected to the failure detection output to the bypass flow control valve from said failure detecting means, the bypass If no flow rate is detected by the flow sensor, a fully closed switching command is output to both the can flow control valve and the bypass flow control valve, while if the flow rate is detected by the bypass flow sensor, the can flow control valve is opened. flow rate value detected by the can flow sensor is configured to burn operation if more than the minimum operating flow rate (claim 1). In the case of the invention according to claim 1, the content of the unique combustion operation control by the failure time control means when the open flow failure occurs in the bypass flow control valve of the can flow control valve and the bypass flow control valve is specified. The Further, in this case, as the control means at the time of failure, when the combustion operation is performed, the hot water temperature to the hot water supply path is adjusted by adjusting the combustion amount based on both flow rate detection values by the bypass flow rate sensor and the can flow rate sensor. You may add the structure which carries out a combustion operation so that it may become preset hot water supply temperature (Claim 2 ). In this way, not only the hot water temperature in the hot water supply path is prevented from being lowered, but also the hot water heater in which the open flow failure has occurred in the bypass flow rate control valve can be specifically supplied at the set hot water temperature. It becomes possible to maintain the hot-water supply temperature for the hot-water tap through the path at the set hot-water supply temperature.

In addition to the above-mentioned premise configuration, in the connected hot water supply apparatus according to claim 3 , as a failure time control means in the premise configuration, when a failure body detection control output is received from the failure detection means to the can body flow control valve, If there is no flow rate detection by the can body flow sensor, a fully closed switching command is output to both the can body flow control valve and the bypass flow control valve, while if the flow rate detection value by the can body flow sensor is greater than the minimum operating flow rate It has a structure to burn operation (claim 3). In the case of the invention according to claim 3, the content of the unique combustion operation control by the failure time control means when the open flow failure occurs in the can flow control valve of the can flow control valve and the bypass flow control valve is specified. Is done. Further, in this case, as a control means at the time of failure, when the combustion operation is performed, the bypass flow rate by the bypass flow rate control valve is adjusted based on the flow rate detection value and the combustion amount by the can body flow rate sensor to You may add the structure which carries out a combustion operation so that a tapping temperature becomes set hot water supply temperature (Claim 4 ). By doing in this way, not only the decrease in the hot water supply temperature of the hot water supply path can be prevented, but also the hot water supply at the set hot water temperature can be specifically made possible from the water heater in which the open flow failure has occurred in the can body flow control valve, It becomes possible to maintain the hot-water supply temperature for the hot-water tap through the hot-water supply path at the set hot-water supply temperature.

As described above, according to any of the connected hot water supply apparatuses according to any one of claims 1 to 4 , a specific hot water supply in which an open failure has occurred in the can flow control valve and / or the bypass flow control valve is a system. Since it can be separated from the control target of the number control by the controller and the specific water heater can be controlled independently by itself, the water from the water supply path can flow through the open- flow can body flow control valve and / or the bypass flow control valve. Generation | occurrence | production of the situation where hot water supply temperature falls with flowing out to a hot water supply path | route can be prevented.

That is, each water heater constituting the connected hot water supply apparatus includes a can flow control valve and a bypass flow control valve, and water flows from the water supply path to the hot water supply path even if any flow control valve has an open failure. Even in the configuration that ends up in a state, it is possible to prevent the occurrence of a situation in which the temperature of the hot water supplied from the hot water supply path to the hot water tap decreases.

In particular, according to claim 1 , the content of the unique combustion operation control by the failure time control means when an open failure occurs in the bypass flow control valve of the can flow control valve and the bypass flow control valve is specified. Can do. Furthermore, according to the second aspect , not only can a decrease in the hot water supply temperature of the hot water supply path be prevented, but also hot water can be supplied at a set hot water temperature from a water heater in which an open failure has occurred in the bypass flow rate control valve. The hot water supply temperature for the hot water tap can be maintained at the set hot water supply temperature.

According to the third aspect of the present invention , the contents of the unique combustion operation control by the failure time control means when the open flow failure occurs in the can flow control valve of the can flow control valve and the bypass flow control valve are specifically described. Can be specified. Furthermore, according to the fourth aspect , not only can a decrease in the hot water supply temperature of the hot water supply path be prevented, but also hot water can be supplied at the set hot water temperature from a water heater in which an open failure has occurred in the can body flow rate control valve. The hot-water supply temperature for the hot-water tap can be maintained at the set hot-water supply temperature through the path.

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

  FIG. 1 shows a connected hot water supply apparatus according to an embodiment of the present invention. In this embodiment, two or more water heaters 2 having the same configuration are connected in parallel between a water supply path 4 and a hot water supply path 5. That is, two or more hot water heaters 2 having the same configuration are used (FIG. 1 illustrates the case of four water heaters, and reference numerals 2a, 2b,. Are connected in parallel to the water supply path 4 for receiving water from a water pipe or the like, and the hot water outlets 230 are connected in parallel to the hot water supply path 5 following the hot water tap 51. Further, apart from the controller 3 of each of the water heaters 2a, 2b,... (In the figure, the reference numerals 3a, 3b,... Are also attached in order for distinction), all the water heaters 2a, 2b,. As a system controller 6 for controlling the number control and the like, the controllers 3 of all the hot water heaters 2a, 2b,... Are connected to the system controller 6 through the communication connection line 13 so as to be able to communicate individually. ing. The system controller 6 recognizes the number of connected units and the water heaters 2a, 2b,... By being individually connected to each controller 3 through the communication connection line 13 so as to be capable of bidirectional communication. It is recognized that the self is not a single installation type but a connection type and performs operation control based on a control command from the system controller 6. A main remote controller 61 also serving as a notification unit is connected to the system controller 6 via the communication connection line 12. In addition, the code | symbol 41 in FIG. 5 is a check valve for the backflow prevention to a feed water upstream.

Each water heater 2 (symbol 2 is used as a general term for the symbols 2a, 2b,...) Constituting the above-described connected water heater will be described. Figure 2 shows the oil water heater Ru by burning petroleum (e.g. kerosene) as a fuel as an example of the water heater 2. The hot water heater 2 illustrated in FIG. 2 burns kerosene with the combustion burner 25, heats the incoming water from the water inlet 220 with the combustion heat, and discharges the heated hot water from the outlet 230. As long as it has such a function, the connected hot water supply apparatus of the present invention is configured using another type that does not use the heat exchanger 21 described later, or a gas water heater that burns gas as fuel. Can do.

  The water heater 2 includes a heat exchanger 21 disposed in the combustion can body 20, a water inlet 22 through which water from the water supply path 4 (see FIG. 1) enters the heat exchanger 21 through a water inlet 220, A hot water path 23 for discharging hot water heated by the heat exchanger 21 from the hot water outlet 230 to the hot water supply path 5 (see FIG. 1), and a bypass for mixing water with the hot water discharged from the heat exchanger 21 A passage 24, a combustion burner 25 as a combustion section for heating the heat exchanger 21 with combustion heat, a fuel supply pipe 261 and a fuel supply pipe for supplying fuel oil (kerosene) from a fuel tank 26 to the combustion burner 25 262. The fuel supply pipe 261 (see also FIG. 1) is piped on site from the fuel tank 26 installed on the site to the water heater 2, and the fuel supply pipe 262 constitutes the water heater 2. It is provided in advance as a part to do. The water inlet 22, the hot water outlet 23, and the bypass 24 constitute the water passage of the water heater 2.

  A can body flow rate sensor 221 for detecting an incoming water flow rate (hereinafter also referred to as a “can body flow rate”) that enters the combustion can body 20 as a part of the water flow rate detection means in the water inlet passage 22 and its incoming water temperature. While the incoming water temperature sensor 222 is provided to detect the temperature, the outlet hot water passage 23 is heated by the combustion can body 20 at a position upstream of the mixed water portion (stirring portion) 243 at the joining position with the downstream end of the bypass passage 24. A can body temperature sensor 231 for detecting a tapping temperature (can body temperature) immediately after being performed, and a can body flow rate control valve 232 for adjusting a tapping flow rate are provided as part of the water flow rate control valve. A hot water supply temperature sensor 233 for detecting an actual hot water temperature (hot water supply temperature) is provided at a position downstream of the mixed water portion 243. Further, the bypass passage 24 constitutes a bypass flow sensor 241 that constitutes a part of the water flow rate detection means and the other part of the water flow rate control valve. A bypass flow rate control valve 242 for mixing water from the water inlet 22 at a predetermined mixing ratio is interposed. The can body flow rate control valve 232 and the bypass flow rate control valve 242 are each in a fully closed state in which the valve opening amount is zero based on a control signal, which will be described later, in addition to a normal flow rate adjusting function capable of adjusting the opening within a predetermined valve opening amount range. Has a fully-closed switching function. As a result, when a plurality of hot water heaters 2 are connected and used as a connected type, the can flow control valve 232 and the bypass flow control valve 242 are switched to normal use by switching the use / nonuse of the hot water supply by controlling the number of units. Depending on whether the flow rate adjustment function is activated or whether it is fully closed by the fully closed switching function, it is not necessary to separately provide a dedicated electromagnetic on-off valve.

  The combustion burner 25 is disposed so as to inject the flame downward, and is constituted by, for example, a gun type burner having a return type spray nozzle. The fuel supply pipe 262 is provided with an electromagnetic on-off valve 251 for supplying fuel and an electromagnetic supply pump 252 as a fuel supply pump. The combustion burner 25 sprays kerosene supplied through the fuel supply pipe 262. A part of the kerosene that is burned and supplied is returned to the fuel supply pipe 262 between the electromagnetic on-off valve 251 and the electromagnetic supply pump 252 through the return pipe 253. The return pipe 253 is provided with an oil temperature detection sensor 254 for detecting the oil temperature of the return oil, a flow rate control valve 255 for proportionally controlling the flow rate of the return oil, and a check valve for flowing the return oil only to the return side. Has been. Then, by changing and adjusting the flow rate of the return oil by the flow rate control valve 255 according to the number of tapping hot water, the change of the spray amount from the combustion burner 25 is performed, so that the combustion amount is proportionally controlled. It has become. In the combustion described above, kerosene sprayed from the combustion burner 25 is ignited by an ignition operation from an ignition means (for example, an igniter) 250, and the combustion system 27 is operated by the combustion burner 25, the electromagnetic on-off valve 251, the electromagnetic supply pump 252, and the like. The combustion system 27 is controlled by the controller 3 as will be described later.

  The controller 3 includes a remote control connection port 290 for connecting the communication connection line 12 of the remote control 31 and the communication connection line 13 (see FIG. 1) when the controller 3 is used as a single installation type instead of the connection type of this embodiment. ) Is connected to the communication connection port 291. The controller 3 is used as a connection type, a single hot water control unit that executes hot water control when used as a single installation type, a connected hot water control unit that executes hot water control when used as a connection type, and the like. A failure control unit 32 (see FIG. 3) as a unique control means or a failure control means that executes unique hot water supply control when a failure occurs, and a failure detection unit 33 as a failure detection means. Yes. Recognition of the hot water supply control by the single hot water supply control unit or the hot water supply control by the linked hot water control unit is acquired by the connection of the communication connection line 13 as described above, and this recognition information is stored and held in the nonvolatile memory (EEPRON). It is like that. The connected hot water control unit receives a control signal indicating whether combustion is permitted (uses hot water supply) or prohibits combustion (uses no hot water supply) from the number control unit 62 of the system controller 6 and executes corresponding control. ing. That is, when the combustion prohibition command is received, the can body flow rate control valve 232 and the bypass flow rate control valve 242 are both switched to the fully closed state based on the full close switching command received together with the combustion prohibition command, and the hot water supply 51 is opened. While water from the path 4 is prevented from entering the water inlet 22, at the time of receiving the combustion permission command, at least the can body flow rate control valve 232 is switched based on the opening switching command received together with the combustion permission command, so that the hot water tap 51 If the opening operation is performed, water is supplied from the water supply path 4 to the water inlet path 22. When the hot-water tap 51 is opened and the incoming water flow rate into the incoming water channel 22 becomes equal to or higher than the minimum operating flow rate (MOQ), the combustion system 27 is operated to burn the combustion burner 25.

  When the combustion burner 25 is burned and the hot water supply control is started, the combustion amount is adjusted so that the set hot water supply temperature input to the main remote controller 61 and output to the controller 3 via the system controller 6 is obtained. It has become. For example, based on the incoming water temperature (temperature detected by the incoming water temperature sensor 222) and the can body flow rate (detected flow rate by the can body flow rate sensor 221), the combustion amount is first set by FF control, and then the can body temperature (can body temperature) The combustion amount is set by FB control based on the temperature detected by the sensor 231) or the hot water supply temperature (detected temperature by the hot water supply temperature sensor 233). At this time, by adjusting the flow rate passing through the heat exchanger 21 by the can body flow control valve 232 in relation to the set maximum combustion amount in the combustion burner 25, the can body flow rate, etc., while heating to a predetermined high temperature, Operation control is performed so that the amount of mixed water is adjusted by adjusting the opening degree of the bypass flow rate control valve 242, and the hot water temperature discharged to the hot water supply path 5 becomes the above set hot water temperature.

  On the other hand, in the number controller 62 of the system controller 6 described above, the main water heater that first burns any one water heater (for example, 2a) selected from all the water heaters 2a, 2b,. The roles of the hot water heaters 2b, 2c,... Are assigned to the sub hot water heaters that are additionally combusted to satisfy the hot water demand, and a combustion permission command is sent only to the main hot water heater 2a during the hot water standby, and the other sub hot water heaters 2b, 2c. ,... Are sent with a combustion prohibition command. That is, during the hot water supply standby, the water supply path 4 and the hot water supply path 5 are communicated only via the main water heater 2a, and the other sub water heaters 2b, 2c,. Impossible). When the hot water supply tap 51 is opened and the flow rate of the can body to the main water heater 2a becomes equal to or higher than the MOQ, the main water heater 2a starts to burn and enters the hot water supply control. When there is a shortage of the hot water supply request from the main water heater 2a, a supplement request is output from the main water heater 2a to the system controller 6, and the system controller 36 that receives the request burns to one of the sub water heaters (for example, 2b). A permission command is sent. As a result, the can body flow rate control valve 232 of the sub water heater 2b is opened and switched, and the sub water heater 2b is combusted together with the main water heater 2a when the can body flow rate sensor 221 detects a water flow rate equal to or higher than the MOQ. Further, if the two hot water heaters 2a and 2b are not sufficient for the hot water supply request, a supplement request is output from the sub water heater 2b, and the other sub water heaters 2c are also burned.

  As described above, the other sub-water heaters 2c and 2d are additionally combusted in response to the hot water supply request, while the number of combustion is sequentially reduced in response to the lower hot water supply request. That is, a combustion prohibition command is sent from the system controller 6 to a sub-water heater (for example, 2d) to be excluded from the number of combustion, and the controller 3d of the sub-water heater 2d that receives this command stops combustion of its own combustion burner 25. At the same time, both the can body flow rate control valve 232 and the bypass flow rate control valve 242 are switched to the fully closed state to shut off the water supply path 4 and the hot water supply path 5.

  The assignment of the role of the main water heater is switched every time a predetermined time elapses, or the actual combustion time is accumulated for each of the water heaters 2a, 2b,. It is switched every time (for example, 24 hours).

  The above is the case where various elements are operating normally, but the following control is performed when a failure occurs. That is, in the number control by the system controller 6, if a failure occurs in the can body flow rate control valve 232 and / or the bypass flow rate control valve 242 in any one of the water heaters 2, the specific water heater 2 in which the failure has occurred will be described. Only the system controller 6 is disconnected from the control target of the number control, and the hot water heater 2 in which the failure has occurred is shifted to its own independent control state by the control unit 32 at the time of the failure. That is, when the failure detection unit 33 detects the occurrence of the failure, the failure detection output is transmitted to the system controller 6, and the system controller 6 excludes the specific water heater 2 from the control target (connected number) of the unit control. The number control is continued with the remaining water heaters 2, 2,..., While the specific water heater 2 shifts to the independent operation control by the failure time control unit 32 in response to the failure detection output.

  The failure detection unit 33 includes a switching control command for the can body flow rate control valve 232 and / or the bypass flow rate control valve 242, and the flow rate detection values of the flow rate sensors 221 and 241 in which the flow rate control valves 232 and 242 are installed, Alternatively, the failure is detected by comparison with the driving state (for example, whether or not there is a step-out abnormality) of the valve driving units (for example, stepping motors) of the flow control valves 232, 242. In other words, the can body flow rate sensor 221 and / or the bypass flow rate sensor 241 is output even though the fully closed switching command is output to the can body flow rate control valve 232 and / or the bypass flow rate control valve 242 that have been in the open state so far. When the water flow rate is detected, the can body flow rate control valve 232 and / or the bypass flow rate control valve 242 in the path where the water flow rate is detected sticks in the open state, and an open failure that does not switch fully closed occurs. It is detected that Conversely, the can body flow rate sensor 221 and / or the bypass flow rate sensor is output even though an open switching command is output to the can body flow rate control valve 232 and / or the bypass flow rate control valve 242 that have been fully closed until then. When 241 does not detect the water flow rate, there is a closed failure in which the can body flow rate control valve 232 and / or the bypass flow rate control valve 242 in the flow rate non-detection path is stuck in the fully closed state and is not switched over. Detect when it occurs.

  For each control in the system controller 6 and each controller 3 connected thereto, the case where the bypass flow rate control valve 242 is in failure is referred to the flowchart of FIG. Each case will be specifically described with reference to the flowchart of FIG. Each flow chart shows the control contents in the controller 3, but the control contents in the system controller 6 linked to the controller 3 will also be described below.

  In FIG. 4, it is first determined whether or not the system controller 6 and the controller 3 are connected based on the presence / absence of communication connection via the communication connection line 13, that is, the controller 3 side determines whether the connection type or the single installation type. SA1). If the determination result is “not connected” (NO in step SA1), the controller 3 determines that the controller 3 is not a connection type but a single installation type, and independently controls the hot water supply by the single hot water control unit that the controller 3 has. Is executed (step SA2). On the contrary, if the determination result is “connected” (YES in step SA1), the hot water heater 2 in which the controller 3 is mounted is set as a control target of the number control by the number control unit 62 in the system controller 6. On the other hand, the controller 3 recognizes and stores it as a connected type that receives the number control by the system controller 6. Based on the presence or absence of a failure detection output from the failure detection unit 33, it is determined whether or not a failure has occurred in the bypass flow rate control valve 242 (step SA3). If there is no failure detection output, the system controller 6 controls the number of units. Under the control of the above, the hot water supply control by the connected hot water control unit is executed (NO in step SA3, step SA4).

  If there is a failure detection output in step SA3, the failure detection output is transmitted to the system controller 6 (step SA5). In response to the transmission from the controller 3, the system controller 6 excludes the water heater 2 that has transmitted the failure detection output from the control target of the number control, and shifts to the number control by the remaining number of water heaters 2. Then, in response to the failure detection output, the control shifts to the control by the failure time control unit instead of the hot water supply control by the normal hot water connection control unit (step SA6). That is, the controller 3 switches from the number control by the system controller 6 to shift to independent control (control by the failure time control unit 32) alone.

  When the control by the failure time control unit 32 is entered, if there is a bypass flow rate detection (water flow rate detection) by the bypass flow rate sensor 241 (YES in step SA7), that is, the hot water tap 51 is open (while hot water is being used). If a bypass flow rate is detected due to an open failure of the bypass flow rate control valve 242, the can body flow rate control valve 242 is opened and the can body flow rate sensor 221 detects a can body flow rate equal to or higher than the MOQ. Combustion is started, and thereafter, the combustion amount of the combustion burner 25 is controlled so that hot water is discharged from the hot water supply path 5 at the set hot water supply temperature (step SA8). That is, as a result of heating to a predetermined temperature based on the can body flow rate and the incoming water temperature by the incoming water temperature sensor 222 and mixing water at the bypass flow rate, the temperature detected by the hot water supply temperature sensor 233 becomes the set hot water supply temperature. The FB control of the combustion burner 25 is performed. That is, even if the bypass flow rate control valve 242 has an open failure, the amount of combustion of the combustion burner 25 is FB-controlled so that the set hot water supply temperature is reached as a result of mixed water at the bypass flow rate in the failed state. Hot water can be discharged at the set hot water temperature for the hot water supply path 5. As a result, when the hot water heater 2 in which the failure has occurred is simply prohibited from being burned, that is, when the hot water supply is not used, the hot water temperature for the hot water tap 51 due to unheated water leaking into the hot water supply path 5 through the bypass flow rate control valve 242 in the open failure state. Can be avoided.

  On the other hand, if the bypass flow rate is not detected in step SA7 (NO in step SA7), that is, the bypass flow rate control valve 242 is in the hot water supply standby state in which the hot water tap 51 is closed although an open failure has occurred. If there is no detection, or if the bypass flow rate is not detected regardless of whether the hot water tap 51 is opened or closed because a closed failure has occurred in the bypass flow rate control valve 242, a fully closed switching command is sent to the can body flow rate control valve 232. While being output or maintained to be in a fully closed state, a fully closed switching command is maintained for the bypass flow rate control valve 242 in an open failure state, and the hot water supply is not used without burning (step SA9). In this case, when the hot water tap 51 is opened from the hot water supply standby state, as much water as possible is passed from the water supply path 4 to the other water heaters 2 used for hot water supply. It is possible to prevent an adverse effect on the combustion start operation caused by water entering the MOQ of the vessel 2 or higher. Further, if the hot water tap 51 is opened from the hot water supply standby state with the bypass flow rate control valve 242 open, the water from the water supply path 4 flows through the bypass flow rate control valve 242 in the open failure state. YES in step SA7), the hot water supply at the set hot water supply temperature becomes possible by the unique combustion control (step SA8).

  Next, the case of failure of the can flow control valve 232 will be described with reference to FIG. In this case, it is determined whether or not the system controller 6 is connected (step SA1), and if it is not connected, it is determined that the system is a single installation type and the single hot water supply control is executed (step SA2). If the connection type is used (YES in step SA1), whether or not there is a failure detection output for the can body flow rate control valve 232 instead of the failure detection determination in step SA3 described above. A failure detection determination is performed (step SB3). That is, it is determined whether or not a failure has occurred in the can flow control valve 232 based on the presence or absence of a failure detection output from the failure detection unit 33. If there is no failure detection output, the system controller 6 controls the number of units. Then, the hot water supply control by the connected hot water control unit is executed (NO in step SB3, step SA4).

  If there is a failure detection output in the above step SB3, the failure detection output is transmitted to the system controller 6 (step SA5) as in the case of FIG. The system is excluded from the control targets of the number control and shifts to the number control by the remaining number of water heaters 2. Then, the controller 3 switches from hot water supply control by the connected hot water control unit at normal time to independent control by the failure time control unit 32 (step SA6).

  If the can body flow rate sensor 221 detects the can body flow rate (detection of the water flow rate) (YES in step SB7), that is, the hot-water tap 51 is open (hot water supply is in use), and the can body flow rate control valve 232 is used. If a can body flow rate is detected due to an open failure, the combustion burner 25 is burned on the condition that the can body flow rate is equal to or higher than the MOQ, and then burned so that hot water is discharged from the hot water supply path 5 at a set hot water supply temperature. The combustion amount of the burner 25 is controlled (step SB8). When the control at the time of failure is entered, although the operation command corresponding to a constant opening (predetermined step position) equal to or higher than the MOQ is temporarily output to the can body flow control valve 232 even if it is in a failure state, the subsequent control is performed. The output of the command is stopped, and the temperature adjustment to the set hot water supply temperature is performed mainly by the control of the bypass flow rate control valve 242. That is, the combustion amount of the combustion burner 25 is temporarily set by FF control based on the constant can body flow rate and the incoming water temperature by the incoming water temperature sensor 222, and is set based on the can body temperature of the hot water discharged from the heat exchanger 21. The opening degree of the bypass flow rate control valve 242, that is, the mixed water flow rate is determined so as to reach the hot water supply temperature. Of course, the FB control of the combustion burner 25 may be performed together with the mixed water control by the bypass flow rate control valve 242. Accordingly, as in the case of the failure of the bypass flow rate control valve 242 in FIG. 4, when the hot water heater 2 in which the failure has occurred is simply prohibited from being burned, that is, when the hot water supply is not used, the can flow rate control valve 232 is opened. It is possible to avoid a decrease in the hot water supply temperature with respect to the hot water tap 51 due to unheated water leaking into the hot water supply path 5.

  If the can body flow rate is not detected in step SB7 (NO in step SB7), that is, the can body flow rate control valve 232 has an open failure but the hot water tap 51 is closed and the can is in a hot water standby state. If the body flow rate is not detected, or if the can body flow rate control valve 232 has a closed failure and the can body flow rate is not detected regardless of whether the hot water tap 51 is opened or closed, the can body flow rate control in the failed state is performed. While outputting or maintaining the full-close switching command to the valve 232, the full-close switching command is maintained in the bypass flow rate control valve 242 so as to be fully closed, and the hot water supply is not used without burning (step SB9). As described in step SA9 in FIG. 4, when the hot water tap 51 is opened from the hot water supply standby state, as much water as possible can be passed from the water supply path 4 to the other water heaters 2 used for hot water supply. This is to prevent the hot water heater 2 from adversely affecting the combustion start operation due to the water entering the MOQ or more.

  On the other hand, the failure control by the failure control unit 32 when both of the can flow control valve 232 and the bypass flow control valve 242 are detected as the failure control includes the incoming water temperature by the incoming temperature sensor 222 and the can flow sensor. If the combustion amount control of the combustion burner 25 is performed based on the can body flow rate by 221 and the bypass flow rate (mixed water flow rate) by the bypass flow rate sensor 241, the temperature detected by the hot water supply temperature sensor 233 becomes the set hot water supply temperature. Good. That is, even if an open failure occurs in both cases, the calorific value is calculated based on the flow rate that passes through the can body pre-flow control valve 232 and the bypass flow control valve 242 in the open failure state, and the required combustion amount is determined based on that. By doing so, the hot water can be discharged at the set hot water supply temperature.

  As described above, even if a failure occurs in the can flow rate control valve 232 and / or the bypass flow rate control valve 242 of any of the water heaters 2 constituting the connected hot water supply device, the hot water temperature to the hot water tap 51 is lowered. It is possible to continue hot water supply at the set hot water temperature.

<Other embodiments>
In addition, this invention is not limited to the said embodiment, Various other embodiments are included. That is, in the said embodiment, although the case where the oil water heater which burns liquid fuel (petroleum) as a fuel was used as a hot water heater which comprises a connection type hot water supply apparatus, not only this but gas as said hot water heater. A gas water heater that burns fuel (gas) as fuel may be used.

  In the above-described embodiment, the hot water heater 2 in which the closed failure has occurred is set to a hot water supply non-use state. However, the present invention is not limited to this, and even if a closed failure occurs in the bypass flow rate control valve 242, it is the same as in the case of an open failure. You may make it burn. In this case, hot water having a set hot water supply temperature may be discharged by adjusting the flow rate using the normal can flow control valve 232 and controlling the combustion amount of the combustion burner 25.

  In the above-described embodiment, the control at the time of failure in the case where the connected hot water supply device is configured using the hot water heater 2 that is provided with the bypass passage 24 and the bypass flow rate control valve 242 and can control the temperature by the mixed water has been described. Not limited to the above, the present invention uses a water heater that does not have the above-described bypass path 24 and that is provided only with a can flow control valve and that is switched between water supply path 4 and hot water supply path 5 by switching to the fully closed state. The present invention can also be applied to the configured connected water heater. That is, the present invention can also be applied to a case where a connected hot water supply apparatus is configured using a water heater in which the water flow rate control valve is configured by one can flow control valve.

It is a schematic diagram which shows embodiment of this invention. It is a schematic diagram which shows the example of each water heater which comprises the connection type hot water supply apparatus of FIG. It is a control block diagram of the controller of each water heater of FIG. 1, and a system controller. It is a control flowchart in the controller of each water heater assuming the case where a bypass flow control valve is out of order. It is a control flowchart in the controller of each water heater assuming the case where a can body flow control valve is out of order.

Explanation of symbols

2, 2 a to 2 d Water heater 3, 3 a to 3 d Controller 4 of each water heater 4 Water supply path 5 Hot water supply path 6 System controller 22 Inlet channel (water channel)
23 Hot spring (passage)
24 Bypass (waterway)
32 Control part at the time of failure (control means at the time of failure, original control means)
33 Failure detection unit (failure detection means)
221 Can body flow sensor (water flow detection means)
232 Can body flow control valve (water flow control valve)
241 Bypass flow sensor (water flow detection means)
242 Bypass flow control valve (water flow detection means)

Claims (4)

Two or more water heaters interposed in parallel between the water supply path and the hot water supply path, respectively, and a system controller that controls the number of water heaters to be burned with all these water heaters being controlled Prepared,
Each of the water heaters includes a water inlet connected to the water supply passage, a hot water outlet for letting water entering the water inlet through a heat exchanger for heating to a hot water outlet, and the water inlet bypassing the heat exchanger. A bypass path that mixes the incoming water from the outlet water with the outlet water, a bypass flow control valve that is interposed in the bypass path and has a function of adjusting the flow rate of water and a fully closed switching function, and an inlet path of the bypass path; A can body flow rate control valve having a function of adjusting the water flow rate and a fully closed switching function, which is interposed on a path from the branch position to the hot water path at the junction position of the bypass path through the heat exchanger, and the bypass path At least one of the bypass flow sensor for detecting the water flow rate passing through the heat exchanger, the can flow sensor for detecting the water flow rate passing through the heat exchanger, and the bypass flow control valve and the can flow control valve. To all The fault detection means that detects and outputs the occurrence of a fault that makes it impossible to switch to the system, and when the fault detection output is received from the fault detection means, the system controller departs from the control target by the system controller and has its own hot water supply control. A failure time control means for executing
The system controller is configured to disconnect the hot water heater that has sent out the detection output from the failure detection means when receiving the detection output of the occurrence of an open failure from the target of the operation control by the system controller,
When the failure detection means receives the detection output of the occurrence of the failure in the bypass flow control valve from the failure detection means, both of the can body flow control valve and the bypass flow control valve are detected unless the flow rate is detected by the bypass flow sensor. While a full-close switching command is output, if the flow rate is detected by the bypass flow sensor, the can flow control valve is opened, and the combustion operation is performed if the flow rate detected by the can flow sensor exceeds the minimum operating flow rate. A connected hot water supply apparatus. A linked supply hot water apparatus according to claim 1,
In the case of the combustion operation, the failure time control means adjusts the combustion amount based on both flow rate detection values by the bypass flow rate sensor and the can flow rate sensor so that the hot water temperature to the hot water supply path becomes the set hot water supply temperature. A connected hot water supply device configured to be operated by combustion. Two or more water heaters interposed in parallel between the water supply path and the hot water supply path, respectively, and a system controller that controls the number of water heaters to be burned with all these water heaters being controlled Prepared,
Each of the water heaters includes a water inlet connected to the water supply passage, a hot water outlet for letting water entering the water inlet through a heat exchanger for heating to a hot water outlet, and the water inlet bypassing the heat exchanger. A bypass path that mixes the incoming water from the outlet water with the outlet water, a bypass flow control valve that is interposed in the bypass path and has a function of adjusting the flow rate of water and a fully closed switching function, and an inlet path of the bypass path; A can body flow rate control valve having a function of adjusting the water flow rate and a fully closed switching function, which is interposed on a path from the branch position to the hot water path at the junction position of the bypass path through the heat exchanger, and the bypass path At least one of the bypass flow sensor for detecting the water flow rate passing through the heat exchanger, the can flow sensor for detecting the water flow rate passing through the heat exchanger, and the bypass flow control valve and the can flow control valve. To all The fault detection means that detects and outputs the occurrence of a fault that makes it impossible to switch to the system, and when the fault detection output is received from the fault detection means, the system controller departs from the control target by the system controller and has its own hot water supply control. A failure time control means for executing
The system controller is configured to disconnect the hot water heater that has sent out the detection output from the failure detection means when receiving the detection output of the occurrence of an open failure from the target of the operation control by the system controller,
When the failure detection means receives the detection output of the failure occurrence in the can flow control valve from the failure detection means, the failure control means provides the can flow control valve and the bypass flow control valve unless the flow detection by the can flow sensor is detected. On the other hand, a connected hot water supply device configured to output a full-close switching command and to perform a combustion operation if a flow rate detection value by the can flow sensor is equal to or higher than a minimum operating flow rate. A linked supply hot water apparatus according to claim 3,
The control means at the time of failure causes the hot water temperature to the hot water supply path to the set hot water temperature by adjusting the bypass flow rate by the bypass flow rate control valve based on the flow rate detection value by the can body flow sensor and the combustion amount when the combustion operation is performed. A connected hot water supply device that is configured to perform combustion operation.

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