JP2019132463A - Instantaneous hot water tapping device - Google Patents

Abstract

To provide an instantaneous hot water tapping device capable of controlling the temperature of hot water in a hot water storage tank by taking unevenness of a bypass ratio which could be achieved by a bypass ratio adjustment device properly into consideration.SOLUTION: A controller 45 of an instantaneous hot water tapping device 20 includes: a bypass ratio measurement unit 48 for measuring an actual bypass ratio in a state where a flow rate adjusting valve 33 as a bypass ratio adjusting device is controlled to be a predetermined opening; and a hot water temperature control unit 47 for controlling the temperature of hot water in a hot water storage tank 21 (hot water storage temperature). The hot water storage temperature control unit 47 changes an upper limit value or a target value of the hot water storage temperature according to a measurement value of the bypass ratio.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an immediate hot water supply apparatus.

  Conventionally, for example, as seen in Patent Document 1, a hot water storage tank provided with a heater is provided in the vicinity of a hot water tap (hot water supply terminal) for supplying hot water heated by a hot water heater, and immediately after opening of the hot water tap, Hot water supplied from the hot water flowing out from the hot water storage tank (hot water heated in the hot water storage tank) and the bypass piping while flowing in the hot water storage tank and the bypass piping bypassing the hot water storage tank There is known an immediate hot water discharge apparatus that can perform immediate hot water discharge at a hot water tap by mixing the hot water with the hot water and supplying it to the hot water tap.

JP 2000-186830 A

  As seen in Patent Document 1, hot water heated in a hot water storage tank (hereinafter sometimes referred to as tank-side hot water) and hot water flowing from a water heater via a bypass pipe (hereinafter referred to as bypass-side hot water) Is equipped with a flow rate adjustment valve that can control the flow rate of hot water on the hot water storage tank side, for example, so that the flow rate of the tank side hot water and the bypass side are mixed. The ratio (so-called bypass ratio) with the flow rate of hot water can be variably controlled. As a result, it is possible to control the temperature of hot water supplied to the tap (hot water discharged from the tap) in a wide range.

  On the other hand, in the immediate hot water supply device, the temperature of hot water discharged from the hot water tap (hereinafter, sometimes referred to as hot water temperature) is prevented from becoming excessively high, and the temperature of hot water in the hot water storage tank (hereinafter referred to as hot water temperature). It is desirable to control the hot water storage temperature by limiting the target value to a temperature equal to or lower than a predetermined upper limit value. In this case, in particular, in the immediate hot water supply device provided with the bypass ratio adjusting device such as the flow rate adjusting valve, for example, the ratio of the flow rate of the tank side hot water to the flow rate of the tank side hot water due to the failure of the bypass ratio adjusting device is the maximum ratio. If a problem such that the hot water is constantly maintained occurs, the temperature of the hot water approaches the temperature of the hot water on the tank side and tends to become hot hot water.

  Therefore, it is desirable that the upper limit value of the hot water storage temperature is set so that the hot water temperature does not become excessively high even when the above problem occurs in the state where the hot water storage temperature is controlled using the upper limit value as a target value.

  On the other hand, the actual ratio in the state in which the bypass ratio adjusting device is operated so that the ratio of the tank-side hot water flow rate to the bypass-side hot water flow rate becomes the maximum ratio is the variation of each product of the bypass ratio adjusting device ( For each product of the immediate hot water supply device due to various factors such as deviation from the design specifications), changes over time of the product, or variations in the inner diameter of the piping such as bypass piping (deviation from the design reference value). Variation occurs.

  Therefore, it is desirable that the upper limit value of the hot water storage temperature is set in consideration of the variation in the ratio in the state where the above problem occurs.

  In this case, for example, it is conceivable to set the upper limit value of the hot water storage temperature so as to be adapted to the maximum ratio within the range of variation of the ratio. However, in this case, in the case of an immediate hot water supply device in which the ratio is a low value, the hot water storage temperature is suppressed to be lower than necessary. As a result, there is an inconvenience that the control range of the tapping temperature tends to be limited.

  The present invention has been made in view of such a background, and an immediate hot water discharge device that can control the temperature of hot water in a hot water storage tank in an aspect that appropriately takes into account variations in the bypass ratio that can be realized by the bypass ratio adjusting device. The purpose is to provide.

In order to achieve the above object, the immediate hot water supply apparatus of the present invention has an inflow side pipe connected to the hot water supply pipe so that hot water heated by the heat source machine is supplied from the heat source machine through the hot water supply pipe. A hot water storage tank connected to the inflow side piping so that hot water can be supplied from the inflow side piping, and connected to the hot water storage tank and outlet tap so that hot water in the hot water storage tank can be supplied to the hot water tap An outlet pipe, a bypass pipe connected between the inlet pipe and the outlet pipe so that hot water can flow from the inlet pipe to the outlet pipe without passing through the hot water storage tank, A heating device for heating the hot water in the hot water storage tank at a position near the hot water tap, and immediately after opening the hot water tap, from the hot water supply pipe to the inflow side pipe and the bypass pipe to the outflow side pipe The flowing hot water and the hot water storage A constructed immediately pouring device to supply hot water of a mixture of hot water flowing in the outlet pipe from the click from the outflow pipe to the tapping plug,
A tank-side flow rate that is a flow rate of hot water that flows from the inflow side piping to the outflow side piping through the hot water storage tank in the open state of the hot water tap, and the outflow side from the inflow side piping through the bypass piping A bypass ratio adjusting device that changes a bypass ratio that is a ratio with a bypass-side flow rate that is a flow rate of hot water flowing in the pipe;
A bypass ratio control unit for controlling the bypass ratio by controlling the operation of the bypass ratio adjusting device;
A hot water storage temperature control unit for controlling the hot water storage temperature, which is the temperature of the hot water in the hot water storage tank, by controlling the operation of the heating device;
A bypass in which the bypass ratio control unit measures an actual bypass ratio in a state where the control target of the bypass ratio is set to a predetermined value and the operation of the bypass ratio adjusting device is controlled according to the control target of the predetermined value. A ratio measurement unit,
The hot water storage temperature control unit measures at least one temperature of an upper limit hot water temperature that is an upper limit value of the hot water temperature used for controlling the hot water temperature and a target hot water temperature that is a target value of the hot water temperature. It is comprised so that it may change according to the measured value of the said bypass ratio by a part (1st invention).

  According to the first aspect of the present invention, the upper limit hot water storage according to the measured value of the bypass ratio measured by the bypass ratio measuring unit in a state where the operation control of the bypass ratio adjusting device is performed according to the control target of the predetermined value. Since at least one of the temperature and the target hot water storage temperature is changed, the upper limit hot water storage temperature or the target hot water storage temperature suitable for the actual bypass ratio can be set.

  For this reason, it becomes possible to control the temperature of the hot water in a hot water storage tank in the aspect which considered suitably the dispersion | variation in the bypass ratio which can be implement | achieved with a bypass ratio adjustment apparatus.

  In the first invention, when the bypass ratio is defined as a ratio of the tank-side flow rate to the bypass-side flow rate, the control target of the predetermined value maximizes the bypass ratio realized by the bypass ratio adjusting device. For this reason, it is possible to adopt a mode in which the control target is for that purpose. In this case, the hot water storage temperature control unit realizes the actual bypass ratio by the bypass ratio adjusting device in a state where the actual hot water storage temperature is controlled to one of the upper limit hot water storage temperature and the target hot water storage temperature. By the bypass ratio measuring unit so that the temperature of hot water, which is the temperature of hot water supplied from the outflow side pipe to the hot water tap, remains at a temperature equal to or lower than a predetermined limit value. It is preferable that the one temperature is set using the measured value (second invention).

  According to this, the situation in which the actual bypass ratio is maintained at the maximum bypass ratio that can be realized by the bypass ratio adjusting device due to the failure of the bypass ratio adjusting device (the actual bypass ratio is set to the maximum bypass ratio). The target upper limit temperature and the target hot water storage temperature are set so that the tapping temperature stays at a temperature equal to or lower than the predetermined limit value even if a situation in which the temperature cannot be made smaller than that occurs. This can be done so that one of the temperatures is suitable for the actual value of the maximum bypass ratio.

  As a result, one of the target upper limit temperature and the target hot water storage temperature can be set appropriately without being excessively limited.

  In the first invention or the second invention, when the bypass ratio is defined as a ratio of the tank-side flow rate to the bypass-side flow rate, the control target of the predetermined value is realized by the bypass ratio adjusting device. When the control target is to maximize the bypass ratio, the hot water storage temperature control unit is configured to set the target hot water storage temperature to be higher as the measured value by the bypass ratio measurement unit is smaller. It is preferable (3rd invention).

  Here, when there is a variation in the maximum bypass ratio that can be realized by the bypass ratio adjusting device, the maximum bypass ratio of the bypass ratio adjusting device is set in a state where the bypass ratio adjusting device is operated so as to maximize the bypass ratio. When the actual value of the ratio is a small value, compared to the case where the actual value of the maximum bypass ratio is a large value, the flow rate supplied from the hot water supply pipe to the inflow side pipe The ratio of the flow rate on the tank side decreases and the ratio of the flow rate on the bypass side increases.

  For this reason, if the actual hot water storage temperature is kept at a certain value regardless of the measured value of the maximum bypass ratio, the bypass ratio is maximized, particularly when the incoming water temperature is low. Thus, when the actual temperature of the maximum bypass ratio is a small value, the temperature of the hot water supplied to the tap tap in a state where the bypass ratio adjusting device is operated is the actual value of the maximum bypass ratio. Compared with the case where the value of is a larger value, the temperature is lower (temperature for cooling).

  However, in the third aspect of the invention, the target hot water storage temperature is set to be higher as the measured value (measured value of the actual value of the maximum bypass ratio) by the bypass ratio measuring unit is smaller. As a result, in the state where the hot water storage temperature is controlled to the target hot water storage temperature, when the incoming water temperature is low, the operation control of the bypass ratio adjusting device is performed so as to maximize the bypass ratio. Even if the actual value of the bypass ratio is a small value, it is possible to prevent the tapping temperature from becoming too low.

  In the first to third inventions, in the case where the heat source device is a heat source device that supplies hot water whose temperature is controlled to a preset hot water supply target temperature to the hot water supply pipe, the hot water storage temperature control unit includes: Information indicating the set value of the hot water supply target temperature can be acquired, and the upper limit hot water storage temperature and the target hot water storage temperature are set using the set value of the hot water supply target temperature indicated by the information and the measured value by the bypass ratio measuring unit. It is preferable that either one of the temperatures is set (fourth invention).

  Here, the hot water supply target temperature corresponds to the maximum temperature of the hot water actually supplied from the hot water supply pipe to the inflow side pipe. Therefore, according to the fifth aspect of the invention, the upper limit hot water storage temperature or the target hot water storage temperature is set in a manner that reflects the maximum temperature of hot water actually supplied to the inflow side pipe in addition to the actual bypass ratio. it can.

  In this case, particularly when the fifth aspect of the invention is combined with the third aspect of the invention, the upper limit hot water temperature or the target hot water temperature at which the tapping temperature can be kept below the limit value can be set even more suitably. It becomes possible.

The figure which shows the whole structure of the system containing the immediate hot water apparatus in embodiment of this invention. The block diagram which shows the function of the immediate hot water controller shown in FIG. The flowchart for demonstrating the process of the bypass ratio measurement part shown in FIG.

[First Embodiment]
A first embodiment of the present invention will be described below with reference to FIGS. With reference to FIG. 1, an immediate hot water supply device 20 of the present embodiment performs immediate hot water discharge at any one hot water tap 1 to be hot water supplied in an arbitrary dwelling unit provided with a hot water supply device 3 capable of performing a hot water supply operation. It is a device installed to obtain.

  The hot water tap 1 is a hot water tap arranged in, for example, a kitchen, a washroom, or a bathroom. In FIG. 1, the hot-water tap 1 is described as a faucet (caran). However, the hot-water tap 1 is not limited to a faucet, and may be, for example, a shower or a composite of a shower and a faucet. .

  The water heater 3 includes a heat source device 4 as its main body. The heat source unit 4 is, for example, a combustion type heat source unit that includes a burner and a heat exchanger (not shown), and includes a water supply pipe 5 that introduces hot water supply water such as tap water into the heat source unit 4, and the heat source unit 4. The hot water supply water (hot water) heated by the combustion heat of the burner is connected to a hot water supply pipe 6 for supplying each hot water supply target part including the hot water tap 1. Note that the burner fuel may be either gaseous fuel or liquid fuel such as kerosene.

  The hot water supply pipe 6 is led out from the heat source unit 4, and a downstream part thereof (downstream part reaching the hot water tap 1) is connected to the hot water tap 1 via an immediate hot water outlet 20. Note that other hot-water taps other than the hot-water tap 1 can be connected to the hot-water supply pipe 6.

  The water heater 3 further includes a controller 8 that controls the operation of the heat source unit 4 and a remote controller 9 for operating the water heater 3. The remote controller 9 is disposed in a kitchen, a bathroom, or the like, and can perform wired communication (or wireless communication) with the controller 8. By operating this remote controller 9, the controller 8 is instructed to start or stop operation of the water heater 3, or the target of the temperature (hot water temperature) of hot water supplied from the heat source unit 4 to each hot water supply target part including the hot water tap 1 is reached. It is possible to set a value.

  Although only a single remote controller 9 is illustrated in FIG. 1, the water heater 3 may further include one or more remote controllers other than the remote controller 9.

  The controller 8 (hereinafter referred to as a hot water supply controller 8) is configured by one or more electronic circuit units including a microcomputer, a memory, an interface circuit, and the like, and is mounted on the heat source unit 4. And the hot water supply controller 8 controls the operation of the heat source unit 4 related to the hot water supply operation by the implemented hardware configuration and program (software configuration).

  Specifically, when water flow through the water supply pipe 5 is started by opening one of the hot water taps such as the hot water tap 1 or the like, the hot water supply controller 8 starts the water flow with a water flow switch (not shown) or It detects through sensors, such as a flow sensor, and starts the combustion operation of the burner of the heat source unit 4 according to the detection. Thereby, hot water for hot water introduced from the water supply pipe 5 to the heat source unit 4 is heated by the combustion heat of the burner through the heat exchanger, and the hot water for hot water (hot water) after the heating is supplied to the opened hot water tap. It is supplied from the heat source device 4 through the hot water supply pipe 6.

  Then, the hot water supply controller 8 adjusts the burner combustion amount so that the actual hot water supply temperature to the opened hot water tap matches or substantially matches the target value set by the remote controller 9 (hereinafter referred to as hot water supply target temperature). Control.

  Supplementally, the heat source unit 4 of the water heater 3 is not limited to a combustion type heat source unit, but is a heat source unit including an electric heating unit (including a heat pump type) instead of or in addition to the burner. There may be. The water heater 3 is configured not only to perform a hot water supply operation, but also to perform a bath operation such as hot water for a bathtub, or an operation for supplying hot water to a hot water heating device such as a bathroom heating device. Also good.

  The immediate hot water supply device 20 is installed on a flow path of hot water from the heat source device 4 to the hot water tap 1 at a position sufficiently closer to the hot water tap 1 than the heat source device 4 (position close to the hot water tap 1). The immediate hot water supply device 20 includes a hot water storage tank 21, an inflow side pipe 30 connected to the downstream end of the hot water supply pipe 6, and an outflow side pipe 31 connected to the hot water tap 1.

  The downstream end of the inflow side pipe 30 is connected to the lower end of the hot water storage tank 21 so that hot water flowing into the inflow side pipe 30 from the hot water supply pipe 6 (hot water entering the immediate hot water supply device 20) can be supplied to the hot water storage tank 21. Has been.

  Further, the upstream portion of the outflow side pipe 31 is introduced into the hot water storage tank 21 so that hot water in the hot water storage tank 21 can be supplied to the hot water tap 1. In this case, the upstream end of the outflow side pipe 31 opens into the hot water storage tank 21 at the upper part of the hot water storage tank 21. The upstream end of the outflow side pipe 31 may be connected to the upper part of the hot water storage tank 21.

  Inside the hot water storage tank 21, an electric heater 22 as a heating device for heating the hot water in the hot water storage tank 21 and a rectifying plate 23 that rectifies the hot water flowing into the hot water storage tank 21 from the inflow side pipe 30. And are incorporated.

  Further, a temperature sensor 24 for detecting the temperature of hot water in the hot water storage tank 21 (hereinafter referred to as hot water storage temperature Ttk) and a hot water storage tank 21 in an excessively high temperature overheat state are provided at the outer periphery of the hot water storage tank 21. An overheat prevention thermostat 25 that forcibly cuts off the power supply to the heater 22 and a heat insulating material 26 that covers the upper portion of the hot water storage tank 21 are mounted in order to improve the heat retaining property of the hot water storage tank 21.

  A bypass that forms a flow path for flowing hot water from the inflow side pipe 30 to the outflow side pipe 31 without passing through the hot water storage tank 21 between the midway part 30a of the inflow side pipe 30 and the midway part 31a of the outflow side pipe 31. A pipe 32 is connected to the hot water storage tank 21 in parallel.

  A flow rate of hot water flowing into the hot water storage tank 21 from the intermediate portion 30a (hereinafter referred to as a tank-side flow rate) is provided in a portion of the inflow side piping 30 downstream of the intermediate portion 30a (connection portion of the bypass piping 32). And a flow rate adjusting valve 33 that functions as a bypass ratio adjusting device that changes a bypass ratio that is a ratio of the flow rate of hot water flowing into the bypass pipe 32 from the intermediate portion 30a (hereinafter referred to as a bypass side flow rate). ing.

  The flow rate adjustment valve 33 is configured by an electromagnetic proportional valve or an electric servo valve that can change the opening degree between a fully closed state and a fully open state, and the opening degree of the flow rate adjustment valve 33 is changed. By doing so, it is possible to change the bypass ratio.

  The bypass ratio is more specifically the ratio of the other of the tank side flow rate and the bypass side flow rate to the other. In the description of this embodiment, for convenience, the ratio R (= tank side flow rate / bypass side flow rate) of the tank side flow rate to the bypass side flow rate is defined as the bypass ratio R. In this case, the bypass ratio R increases as the opening degree of the flow rate adjustment valve 33 increases, and becomes zero (minimum value) when the flow rate adjustment valve 33 is fully closed, and becomes maximum when the flow rate adjustment valve 33 is fully open.

  A temperature sensor 34 for detecting the temperature of hot water supplied from the hot water supply pipe 6 (hereinafter referred to as the incoming water temperature Tin) and a hot water supply pipe 6 are supplied to the upstream side of the intermediate portion 30 a of the inflow side pipe 30. A flow rate sensor 35 for detecting the flow rate of hot water (hereinafter referred to as the incoming water flow rate Win) and a valve mechanism 36 including a pressure reducing valve and a check valve (not shown) are assembled.

  An expansion water discharge pipe 37 for discharging a part of the hot water expanded by heating in the hot water storage tank 21 is connected to a portion of the inflow side pipe 30 on the downstream side of the flow rate adjustment valve 33. The water discharge pipe 37 is provided with an overpressure relief valve 38 that opens when the pressure of the hot water in the hot water storage tank 21 rises to a pressure equal to or higher than a predetermined value. The expansion water discharge pipe 37 may be connected to the hot water storage tank 21 or the outflow side pipe 31.

  The temperature of hot water flowing out from the hot water storage tank 21 to the outflow side piping 31 (hereinafter referred to as the tank outflow temperature Ttout) is detected in a portion upstream of the middle portion 31a of the outflow side piping 31 (connection portion of the bypass piping 32). A temperature sensor 39 is assembled. Moreover, the temperature of the hot water supplied from the middle part 31a to the tap 1 and discharged from the tap 1 (hereinafter referred to as the tapping temperature Tout) is provided in the downstream part of the middle part 31a of the outflow side pipe 31. A temperature sensor 40 to be detected is assembled.

  In the middle part of the outflow side pipe 31 (in the illustrated example, the middle part 31a), water for draining hot water or the like in the hot water storage tank 21 when the immediate hot water supply device 20 is maintained or not used. An extraction pipe 41 is connected. A drain plug 42 that can be manually opened and closed is attached to the downstream end of the drain pipe 41.

  The immediate hot water supply device 20 further includes a controller 45 that controls the operation of the heater 22 and the flow rate adjustment valve 33 of the hot water storage tank 21 (hereinafter referred to as an immediate hot water controller 45), an on / off operation of the power supply of the immediate hot water supply device 20, And an operation unit 50 for performing an operation condition setting operation of the immediate hot water supply device 20.

  The operation unit 50 includes operation switches, a display unit, and the like (not shown). The immediate hot water controller 45 includes one or more electronic circuit units including a microcomputer, a memory, an interface circuit, and the like. The operation signal of the operation unit 50 is input to the temperature sensor 24, 34, 39, 40 and the flow rate. A detection signal of the sensor 35 is input.

  Further, in this embodiment, the immediate hot water controller 45 can perform wired communication (or wireless communication) with the hot water controller 8, and information indicating the hot water supply target temperature set by the remote controller 9 by this communication, etc. Is possible to get.

  Then, as shown in FIG. 2, the immediate hot water controller 45 performs operation control of the flow rate adjustment valve 33 at the time of hot water at the hot water tap 1 as a function realized by the implemented hardware configuration and program. The hot water storage temperature control unit 47 controls the hot water storage temperature Ttk (the temperature of hot water in the hot water storage tank 21) by controlling the operation of the heater 22 and the function of the bypass ratio control unit 46 for controlling the bypass ratio R. In the state where the opening degree of the flow rate adjusting valve 33 is maintained at a predetermined opening degree corresponding to a predetermined value of the bypass ratio, the actual bypass at the opening degree is maintained during the trial operation of the hot water supply device 20 described later. And a function as a bypass ratio measuring unit 48 for measuring the ratio.

  Here, supplementing with respect to the bypass ratio R, the inner diameters of the inflow side piping 30 and the bypass piping 32 used in the immediate hot water supply device 20 and the specifications (specifications) of the flow rate adjustment valve 33 are basically the flow rate adjustment. The relationship between the opening degree of the valve 33 and the bypass ratio R is determined by design so that the required constant relationship is obtained. That is, the inner diameter and the specifications are based on a predetermined standard in which the bypass ratio R in a state in which the opening degree of the flow regulating valve 33 is controlled to a certain predetermined opening degree is designed according to the predetermined opening degree. It is determined to be a value.

  However, due to variations in the inner diameter of each product of the inflow side piping 30 and the bypass piping 32 that are actually used in the individual immediate hot water supply devices 20, variations in the actual specifications of each product of the flow regulating valve 33, etc. The actual bypass ratio R in a state where the opening degree of the flow rate adjustment valve 33 is maintained at a predetermined opening degree varies with respect to the reference value corresponding to the predetermined opening degree.

  Further, for example, due to deterioration over time of the flow rate adjusting valve 33, contamination over time inside the inflow side pipe 30 or the outflow side pipe 31, and the like, the actual bypass ratio R is changed from a value near the reference value over time. May change.

  In consideration of such variations, the bypass ratio measuring unit 48 performs actual bypass in a state where the opening degree of the flow rate adjustment valve 33 is maintained at a predetermined opening degree, for example, an opening degree in a fully open state (maximum opening degree). The ratio R is measured. In this case, the reference value (design reference value) of the bypass ratio corresponding to the opening degree of the flow regulating valve 33 in the fully opened state corresponds to the control target in the present invention.

  In the following description, a reference symbol Rx is added to the actual bypass ratio R in a state where the opening of the flow rate adjustment valve 33 is maintained at the fully opened position, and the bypass ratio R corresponding to the fully opened position is determined. The reference value R0 is attached to the reference value. In other words, the reference value R0 is a design setting value (for example, R0 = 1 / 1.5) of the maximum value of the bypass ratio R.

  Next, the operation of the immediate hot water supply apparatus 20 of the present embodiment will be described focusing on the control process of the immediate hot water controller 45. In the present embodiment, immediately after the installation of the immediate hot water supply apparatus 20 or at the time of maintenance or the like, a trial operation of the immediate hot water supply apparatus 20 is performed. Then, the immediate hot water controller 45 performs an actual bypass ratio Rx in a state in which the opening degree of the flow rate adjustment valve 33 is controlled to an opening degree corresponding to the bypass ratio of the reference value R0 (opening degree in the fully open state) during the trial operation. The process for measuring is executed.

  Specifically, when a predetermined operation of the operation unit 50 is performed in order to perform a trial operation of the immediate hot water supply device 20, the immediate hot water controller 45 executes a process shown in the flowchart of FIG. In this case, in STEP 1, the immediate hot water controller 45 determines the presence or absence of water entering the immediate hot water supply device 20 (inflow of hot water from the hot water supply pipe 6 to the inflow side pipe 30) based on the detection signal of the flow sensor 35.

  At this time, if the hot-water tap 1 is opened, water is immediately supplied to the hot-water supply device 20, so that the determination result in STEP 1 is positive. In this case, the immediate hot water controller 45 continues the determination process of STEP1. In this case, a notification output (visual or audible notification output) indicating that the tap 1 should be closed may be generated.

  In the closed state of the hot-water tap 1, since the water entering the immediate hot-water supply device 20 is blocked, the determination result of STEP 1 becomes negative. In this case, the immediate hot water controller 45 then operates the heater 22 so as to boil (heat) the hot water in the hot water storage tank 21 to a predetermined temperature in STEP2. The predetermined temperature is a temperature set to be higher than the incoming water temperature Tin. The predetermined temperature may be a predetermined fixed temperature (for example, a temperature higher than the maximum value of the variable range of the hot water supply target temperature) by a predetermined value. For example, the detected value of the incoming water temperature Tin detected by the temperature sensor 34 The temperature may be set according to the temperature.

  The immediate hot water supply apparatus 20 further determines in STEP 3 whether or not the boiling has been completed. In STEP 3, the immediate hot water controller 45 determines whether or not the boiling has been completed by determining whether or not the detected value of the hot water storage temperature Ttk indicated by the detection signal of the temperature sensor 24 has reached a predetermined temperature. to decide.

  If the determination result in STEP 3 is negative, the immediate hot water controller 45 continues the processing in STEPs 2 and 3.

  When the boiling of the hot water in the hot water storage tank 21 is completed and the determination result in STEP 3 becomes affirmative, the immediate hot water controller 45 then causes the bypass ratio control unit 46 to set the flow rate adjustment valve 33 in STEP 4. The opening degree is controlled to the opening degree in the fully open state that is the opening degree corresponding to the reference value R0. In other words, the bypass ratio control unit 46 sets the target value of the bypass ratio R as the reference value R0, and sets the flow rate adjustment valve 33 to the opening degree (here, the opening degree in the fully open state) defined in accordance with the target value. To control the opening degree.

  And the immediate hot water controller 45 performs the processing of STEP5-9 by the said bypass ratio measurement part 48 in the state by which the opening degree of the flow regulating valve 33 was controlled to the opening degree of a full open state. The immediate hot water controller 45 operates the heater 22 intermittently or stops the operation of the heater 22 so as to maintain the hot water storage temperature Ttk at a predetermined temperature after the boiling of the hot water in the hot water storage tank 21 is completed. Let

  In STEP 5, the bypass ratio measurement unit 48 generates a notification output indicating that the immediate hot water supply device 20 is being tested (by measuring the bypass ratio R). As the notification output, for example, lighting or blinking of a display lamp provided in the operation unit 50, display on the display unit, acoustic output, audio output, or the like can be used.

  And in STEP6, the bypass ratio measurement part 48 judges the presence or absence of the water to the immediate hot water apparatus 20 based on the detection signal of the flow sensor 35 similarly to said STEP1, and until this judgment result becomes affirmative. The determination process of STEP 6 is continued (until water is detected).

  In this case, a notification output (visual or audible notification output) indicating that the hot-water tap 1 should be opened may be generated in order to start entering the immediate hot water supply apparatus 20.

  When the water tap 1 is opened and water is immediately entered into the hot water tap device 20, the determination result in STEP 6 becomes affirmative. In this case, the bypass ratio measuring unit 48 detects the incoming water temperature Tin, the tank outlet temperature Ttout, and the tapping temperature Tout from the detection signals of the temperature sensors 34, 39, and 40, respectively, in STEP7.

  Next, in STEP 8, the bypass ratio measuring unit 48 estimates the actual bypass ratio Rx in the fully opened state of the flow rate adjustment valve 33 from the detected values of the incoming water temperature Tin, the tank outlet temperature Ttout, and the tapping temperature Tout. The estimated value is stored in the memory of the controller 45 as a measured value of the actual bypass ratio Rx.

  Here, the relationship between the water temperature Tin, the tank outflow temperature Ttout and the hot water temperature Tout and the bypass ratio R (here, R = tank side flow rate / bypass side flow rate) is generally expressed by the following equation (1). be able to.

Tout × (1 + R) = Tin × 1 + Ttout × R (1)

  Therefore, in STEP 8, the bypass ratio measurement unit 48 performs actual bypass from the detected values of the incoming water temperature Tin, the tank outlet temperature Ttout, and the tapping temperature Tout by the calculation of the following equation (2) obtained from the equation (1). An estimated value (measured value) of the ratio Rx is calculated.

Rx = (Tout-Tin) / (Ttout-Tout) (2)

  The bypass ratio Rx calculated in this way means the maximum value of the bypass ratio R (= tank side flow rate / bypass flow rate) actually realized by controlling the opening degree of the flow rate adjustment valve 33. When the bypass ratio is defined as bypass flow rate / tank side flow rate, the reciprocal value (= 1 / Rx) of the value of Rx calculated by equation (2) is controlled by controlling the opening degree of the flow rate adjustment valve 33. This is the minimum value of the actual bypass ratio.

  Next, in STEP 9, the bypass ratio measuring unit 48 stops the notification output indicating that the immediate hot water supply device 20 is being tested (during measurement of the bypass ratio R).

  As described above, the bypass ratio Rx is measured by the bypass ratio measuring unit 48 when the hot water in the hot water storage tank 21 is boiled and the opening of the flow rate adjustment valve 33 is in a fully opened state corresponding to the reference value R0 of the bypass ratio R. In the state controlled to the opening degree, it is performed by starting the water supply to the immediate hot-water supply apparatus 20 by opening the hot-water tap 1.

  Note that immediately after the determination result of STEP 6 becomes affirmative, the tank outflow temperature Ttout detected in STEP 7 substantially coincides with the hot water storage temperature Ttk immediately before the determination result of STEP 6 becomes affirmative. Therefore, in STEP 8, instead of the detected value of the tank outflow temperature Ttout, for example, the bypass ratio Rx is set using the detected value of the hot water storage temperature Ttk detected by the temperature sensor 24 immediately before the determination result in STEP 6 becomes affirmative. It may be calculated.

  The measured value of the bypass ratio Rx obtained by the above-described measurement process generally coincides with or substantially coincides with the reference value R0, but causes some variation with respect to the reference value R0. For example, when the reference value R0 is R0 = 1 / 1.5, the measured value of the bypass ratio Rx can take values such as 1 / 1.4, 1 / 1.6, and the like.

  Next, the control of the hot water storage temperature Ttk during normal operation of the immediate hot water supply device 20 will be described. In the present embodiment, the hot water storage temperature control unit 47 of the immediate hot water controller 45 determines the hot water storage temperature Ttk as a target when the detected value of the hot water storage temperature Ttk indicated by the detection signal of the temperature sensor 24 is lower than a predetermined temperature. The hot water in the hot water storage tank 21 is boiled so as to increase the temperature to the target hot water storage temperature Ttk_cmd, and the heater is further maintained (maintains) the hot water storage temperature Ttk at or substantially equal to the target hot water storage temperature Ttk_cmd. 22 is activated.

  In this case, the hot water storage temperature control unit 47 determines an upper limit hot water storage temperature Ttk_limH that is an upper limit value of the hot water storage temperature Ttk, and then determines a target hot water storage temperature Ttk_cmd within a range equal to or lower than the upper limit hot water storage temperature Ttk_limH.

  In the present embodiment, the upper limit hot water storage temperature Ttk_limH is, for example, a failure of the flow rate adjustment valve 33 when the incoming water temperature Tin, which is the temperature of hot water entering the hot water supply device 20 from the hot water supply pipe 6, is within a predetermined range. As a result, the opening degree of the flow rate adjustment valve 33 is held at the fully open position (and the actual bypass ratio R is held at the bypass ratio Rx as the maximum value). The hot water in the hot water storage tank 21 and the hot water entering the immediate hot water supply device 20 are mixed at the intermediate portion 31a of the outflow side pipe 31 (hereinafter referred to as the mixing portion 31a), and the hot water temperature Tout (the mixing portion) is obtained. The temperature of the hot water supplied from 31a to the hot water tap 1 is determined to remain at a temperature equal to or lower than a predetermined limit value Tout_limH.

  In this case, in the present embodiment, the predetermined range of the incoming water temperature Tin is a temperature range equal to or lower than a predetermined upper limit incoming water temperature TinH. And the hot water storage temperature control part 47 sets the upper limit side incoming water temperature TinH so that it may be changed according to the said hot water supply target temperature set with the remote control 9 of the water heater 3. FIG.

  Specifically, the hot water storage temperature control unit 47 acquires a set value of the hot water supply target temperature through communication with the hot water supply controller 8 of the hot water heater 3. Then, the hot water storage temperature control unit 47 sets, for example, the set value of the hot water supply target temperature or a temperature higher than the set value by a predetermined margin value as the upper limit side incoming water temperature TinH. Therefore, the upper limit side incoming water temperature TinH is variably set so as to increase or decrease according to the increase or decrease of the hot water supply target temperature.

  In addition, when the hot water supply target temperature is set to a value larger than the maximum value (for example, 48 ° C.) of the standard normal range of the hot water supply target temperature, for example, the upper limit side incoming water temperature TinH is set to the hot water supply target temperature. Limiting to a value corresponding to the maximum value of the normal temperature range (in other words, assuming that the set value of the hot water supply target temperature is the maximum value of the normal range, the upper limit side incoming water temperature TinH corresponding to the maximum value) May be set).

  Then, the hot water storage temperature control unit 47 uses the upper limit side incoming water temperature TinH set as described above and the measured value of the actual bypass ratio Rx obtained by the above-described measurement process of the bypass ratio measurement unit 48, and uses the upper limit hot water storage temperature TinH. The temperature Ttk_limH is determined.

  Here, the relationship among the incoming water temperature Tin, the tank outflow temperature Ttout, the hot water temperature Tout, and the bypass ratio R is expressed by the equation (1). Accordingly, the hot water storage temperature control unit 47 uses the limit value Tout_limH of the hot water temperature Tout, the upper limit side incoming water temperature TinH within the range of the incoming water temperature Tin, and the measured value of the bypass ratio Rx according to the following equation (3): The upper limit hot water storage temperature Ttk_limH is determined.

Ttk_limH = (Tout_limH × (1 + Rx) −TinH) / Rx
= Tout_limH + (Tout_limH-TinH) / Rx (3)

  This expression (3) is an expression obtained by modifying the expression in which Tout, Tin, Ttout, and R in Expression (1) are replaced with Tout_limH, TinH, Ttk_limH, and Rx, respectively. By determining the upper limit hot water storage temperature Ttk_limH by this equation (3), the upper limit hot water storage temperature Ttk_limH is a temperature within the range where the incoming water temperature Tin is not more than the upper limit side incoming water temperature TinH (when Tin ≦ TinH). Even if the opening degree of the flow rate adjustment valve 33 is maintained at the fully opened degree, the hot water temperature Tout is determined to remain below the limit value Tout_limH (Tout ≦ Tout_limH).

  In this case, when the measured value of the bypass ratio Rx is larger than the reference value R0, the upper limit hot water storage temperature Ttk_limH is determined to be lower than the case where Rx = R0, and the measured value of the bypass ratio Rx is the reference value. When the temperature is smaller than R0, the upper limit hot water storage temperature Ttk_limH is determined to be higher than that when Rx = R0.

  The upper limit hot water storage temperature Ttk_limH may be determined to be a temperature that is lower by a predetermined margin value than the value obtained by the calculation of Equation (3). When the difference between the measured value of the bypass ratio Rx and the reference value R0 is very small within a predetermined range, the upper limit hot water storage temperature Ttk_limH may be determined to be the same as that when Rx = R0. .

  The hot water storage temperature controller 47 determines the target hot water storage temperature Ttk_cmd after determining the upper limit hot water storage temperature Ttk_limH as described above.

  In this process, the hot water storage temperature control unit 47 basically matches the immediate hot water target temperature Tout_cmd as the predetermined target value of the hot water temperature Tout in the predetermined period immediately after the tap tap 1 is opened. The provisional value of the target hot water storage temperature Ttk_cmd is calculated by a predetermined arithmetic expression or the like so that the amount of heat that allows the hot water to be continuously supplied to the tap 1 is stored in the hot water in the hot water storage tank 21.

  For example, as the immediate hot water target temperature Tout_cmd, for example, a hot water supply target temperature set in the hot water heater 3, a value set in advance by the operation of the operation unit 50, or a hot water supply target that can be set in the hot water heater 3 The minimum value of the possible temperature range can be adopted.

  The provisional value of the target hot water storage temperature Ttk_cmd is calculated by, for example, the following equation (4).

Ttk_cmd (provisional value)
= (Tout_cmd × Vin_s−Tin_ave_s × (Vin_s−Vt)) / Vt (4)

  Here, Vin_s is a predicted value of the total amount (volume) of hot water flowing from the hot water supply pipe 6 into the immediate hot water supply device 20 by the end of the predetermined period after the tap tap 1 is opened (hereinafter, the predicted total amount of incoming water Vin_s). Tin_ave_s is a predicted value of the average temperature of hot water flowing from the hot water supply pipe 6 into the immediate hot water supply device 20 by the end of the predetermined period (hereinafter referred to as an average incoming water temperature predicted value Tin_ave_s), and Vt is a value of the hot water storage tank 21. Volume (fixed value).

  The predicted total amount of incoming water Vin_s and the predicted average incoming water temperature Tin_ave_s are determined by the temperature sensor 34 and the flow rate sensor 35, respectively, during the operation of the immediate hot water supply device 20 executed in the past (when hot water is discharged from the hot water tap 1). It is determined based on detection data (detection data in the predetermined period) of the detected incoming water temperature Tin and incoming water flow rate Win. The predetermined period is a period until the temperature detected by the temperature sensor 34 rises to a temperature equal to or higher than the predetermined temperature after the tap tap 1 is opened (after the start of water entering the immediate hot water supply device 20). Alternatively, after opening the tap 1 (after the start of entering the immediate hot water supply device 20), until a predetermined time elapses, or after opening the tap 1 (after entering the immediate hot water device 20) After the start), a period until the total amount of hot water entering the immediate hot water supply apparatus 20 reaches a predetermined value may be employed.

  The hot water storage temperature control unit 47 further compares the provisional value of the target hot water storage temperature Ttk_cmd calculated as described above with the upper limit hot water storage temperature Ttk_limH, and if the provisional value ≦ Ttk_limH, the temporary value is used as it is. The target hot water storage temperature Ttk_cmd for actual control of Ttk is determined. When provisional value> Ttk_limH, hot water storage temperature control unit 47 limits target hot water storage temperature Ttk_cmd for actual control of hot water storage temperature Ttk to upper limit hot water storage temperature Ttk_limH.

  Then, the hot water storage temperature controller 47 controls the heater 22 so that the actual hot water storage temperature Ttk in the hot water storage tank 21 matches or substantially matches the target hot water storage temperature Ttk_cmd determined as described above.

  More specifically, the hot water storage temperature control unit 47 does not pass water to the hot water tap 1 (incoming water immediately into the hot water discharge device 20), and the detected value of the hot water storage temperature Ttk by the temperature sensor 24 is the target hot water storage temperature. When the temperature is lower than Ttk_cmd by a predetermined value or more, the hot water storage temperature Ttk is raised to the target hot water storage temperature Ttk_cmd by starting the heat generation operation of the heater 22 (boiling hot water in the hot water storage tank 21 is boiled). Thereafter, the hot water storage temperature control unit 47 keeps the hot water storage temperature Ttk at a temperature that matches or substantially matches the target hot water storage temperature Ttk_cmd until the water is immediately supplied to the hot water outlet 20 according to the opening of the hot water tap 1. In addition, the heat generation operation and the operation stop of the heater 22 are alternately repeated.

  In the present embodiment, the hot water storage temperature Ttk is controlled as described above.

  Next, the operation at the time of the hot water discharge operation of the immediate hot water supply device 20 (at the time of the operation of performing hot water discharge from the hot water tap 1) will be described. When water enters the immediate hot water supply device 20 according to the opening of the hot water tap 1 (inflow of a predetermined flow rate or more), the immediate hot water controller 45 detects the incoming water based on the detection signal of the flow sensor 35.

  At this time, when the detected value of the hot water storage temperature Ttk indicated by the detection signal of the temperature sensor 24 matches or substantially matches the target hot water storage temperature Ttk_cmd (the detected value of the hot water storage temperature Ttk and the target hot water storage temperature Ttk_cmd) Of the incoming water temperature Tin by the temperature sensors 34, 39, and 40, the detected values of the tank outlet temperature Ttout and the hot water temperature Tout, and the incoming water flow rate Win by the flow sensor 35, respectively. Using the detected value and the immediate hot water target temperature Tout_cmd, the target bypass ratio R_cmd, which is the target value of the bypass ratio R, is calculated in a predetermined manner so that the hot water temperature Tout can be matched or substantially matched with the immediate hot water target temperature Tout_cmd. Sequentially determined by the formula. The upper limit value of the target bypass ratio R_cmd is the reference value R0.

  And the immediate hot water controller 45 controls the opening degree of the flow regulating valve 33 by the bypass ratio control part 46 according to the determined target bypass ratio R_cmd. In this case, the bypass ratio control unit 46 determines a control input that defines the opening degree of the flow rate adjustment valve 33 using a conversion table created in advance from the target bypass ratio R_cmd, and opens the flow rate adjustment valve 33 based on the control input. Control the degree.

  As a result, immediately after the tap 1 is opened, hot water having a temperature that matches or substantially matches the immediate hot water target temperature Tout_cmd is discharged from the tap 1. Thereafter, when hot water heated by the heat source unit 4 (hereinafter simply referred to as heated hot water) enters the hot water outlet 20, the heated hot water is discharged from the hot water tap 1.

  When the target hot water storage temperature Ttk_cmd is limited to the upper limit hot water storage temperature Ttk_limH, there is a possibility that the hot water storage tank 21 will run out before the heated hot water enters the immediate hot water supply device 20. Therefore, when the target hot water storage temperature Ttk_cmd is limited to the upper limit hot water storage temperature Ttk_limH, the immediate hot water target temperature Tout_cmd is corrected to a temperature lower than the temperature when the restriction is not made (normal immediate hot water target temperature Tout_cmd). Then, the target bypass ratio R_cmd may be determined in the same manner as described above using the corrected immediate hot water target temperature Tout_cmd, and the opening degree of the flow rate adjusting valve 33 may be controlled according to the target bypass ratio R_cmd.

  When the detected value of the hot water storage temperature Ttk is lower than the target hot water storage temperature Ttk_cmd by a predetermined value or more (when the temperature rise of the hot water storage temperature Ttk by the heater 22 is not completed), the detected value of the hot water storage temperature Ttk is the incoming water temperature. When it is higher than the detected value of Tin, the immediate hot water controller 45 corrects the immediate hot water target temperature Tout_cmd to a temperature lower than the detected value of the hot water storage temperature Ttk and higher than the detected value of the incoming water temperature Tin, for example. To do. Then, the immediate hot water controller 45 uses the corrected immediate hot water target temperature Tout_cmd to determine the target bypass ratio R_cmd in the same manner as described above, and sets the opening of the flow rate adjustment valve 33 according to the target bypass ratio R_cmd. Control.

  When the detected value of the hot water storage temperature Ttk is lower than the target hot water storage temperature Ttk_cmd by a predetermined value or more (when the temperature rise of the hot water storage temperature Ttk by the heater 22 is not completed), the detected value of the hot water storage temperature Ttk is the incoming water temperature. When the temperature is equal to or lower than the detected value of Tin, the immediate hot water controller 45 determines the target bypass ratio R_cmd so that the entire amount of hot water entering the immediate hot water supply device 20 is supplied to the hot water tap 1 (in this case, R_cmd = 0), the opening degree of the flow regulating valve 33 is controlled according to the target bypass ratio R_cmd. In this case, since R_cmd = 0, the flow rate adjustment valve 33 is controlled to be closed.

  In the present embodiment, the control of the flow rate adjustment valve 33 (and consequently the control of the tapping temperature Tout) during the tapping of the tapping tap 1 is performed as described above.

  By the way, when the hot water tap 1 is discharged, due to a failure of the flow rate adjustment valve 33 or the like, the opening degree of the flow rate adjustment valve 33 is maintained at the fully open position regardless of the target bypass ratio R_cmd. The actual bypass ratio R (= tank side flow rate / bypass side flow rate) is maintained at the maximum value. For this reason, when the target bypass ratio R_cmd is smaller than the reference value R0, the ratio of the tank side flow rate and the bypass side flow rate (tank side flow rate / bypass side flow rate) mixed in the mixing portion 31a of the outflow side pipe 31 is It becomes larger than the target bypass ratio R_cmd.

  As a result, in a situation where the temperature of the hot water flowing out from the hot water storage tank 21 to the outflow side piping 31 becomes a temperature close to the target hot water storage temperature Ttk_cmd, the hot water temperature Tout (supplied from the mixing portion 31a of the outflow side piping 31 to the hot water tap 1). The temperature of the hot water is higher than when the actual bypass ratio R is normally controlled to the target bypass ratio R_cmd. Further, the larger the actual bypass ratio Rx when the opening degree of the flow rate adjustment valve 33 is the opening degree in the fully open state, the larger the flow rate of hot water supplied to the tap 1 from the mixing unit 31a (= incoming flow rate Win). Since the ratio of the tank side flow rate increases, the tapping temperature Tout tends to be higher.

  However, in the present embodiment, the upper limit hot water storage temperature Ttk_limH is set as described above, and the target hot water storage temperature Ttk_cmd is determined within a range equal to or lower than the upper limit hot water storage temperature Ttk_limH. For this reason, when the malfunction that the opening degree of the flow regulating valve 33 is held at the fully opened position occurs, the target hot water storage temperature Ttk_cmd is set to the upper limit hot water storage temperature Ttk_limH, and the actual hot water storage temperature Ttk is set to the upper limit hot water storage temperature. Even in a state where the temperature has reached the temperature Ttk_limH, the incoming water temperature Tin is in a range below the upper limit side incoming water temperature TinH (in this embodiment, the range below the set value of the target hot water temperature, or the set value of the target hot water temperature) In the state where the temperature is within a range lower than the predetermined margin value), the hot water temperature Tout is prevented from becoming higher than the limit value Tout_limH regardless of the actual variation of the bypass ratio Rx. be able to.

  Further, when the measured value of the bypass ratio Rx at the fully opened state of the flow rate adjustment valve 33 is a low value (for example, when Rx <R0), the upper limit hot water storage temperature Ttk_limH is equal to the bypass ratio Rx. Since the measured value is set to a higher temperature than when the measured value is higher (for example, when Rx> R0), the upper limit hot water storage temperature Ttk_limH and consequently the target hot water storage temperature Ttk_cmd is limited to a lower temperature than necessary. Can be prevented.

  As a result, it is possible to suppress as much as possible the amount of heat stored in the hot water storage tank 21 from being deficient in performing hot water at the required immediate hot water target temperature Tout_cmd in a predetermined period immediately after opening the hot water tap 1. As a result, the stability of the hot water discharge performance of the immediate hot water discharge device 20 can be enhanced.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. Note that the present embodiment is different from the first embodiment only in the method of determining the target hot water storage temperature Ttk_cmd, and thus the description of the same matters as the first embodiment is omitted.

  In the present embodiment, the hot water storage temperature controller 47 determines the upper limit hot water storage temperature Ttk_limH determined as described in the first embodiment as the target hot water storage temperature Ttk_cmd. Except for this, the present embodiment is the same as the first embodiment.

  In this embodiment, the same effects as in the first embodiment can be obtained. In addition, in the present embodiment, the following effects can be achieved.

  That is, the smaller the actual bypass ratio Rx (= tank side flow rate / bypass side flow rate) when the opening degree of the flow rate adjustment valve 33 is in the fully opened state, the hot water tap from the mixing part 31a of the outflow side pipe 31 becomes smaller. Since the ratio of the tank-side flow rate in the flow rate of hot water supplied to 1 (= incoming water flow rate Win) decreases, the hot water temperature Tout tends to be lower, but the target hot water storage temperature Ttk_cmd decreases as the bypass ratio Rx decreases. Set to be higher.

  Therefore, when the actual bypass ratio Rx is lower than the reference value R0, the temperature of the incoming water Tin is low (low temperature close to the freezing temperature of water) immediately after the start of the hot water tap 1 in the winter season. ), The temperature of the hot water supplied from the mixing portion 31a of the outflow side pipe 31 to the hot water tap 1 (that is, the hot water temperature Tout) can be prevented from becoming too low.

[Other Embodiments]
In addition, this invention is not limited to embodiment described above, Embodiment of another aspect can also be employ | adopted. Several other embodiments will be described below.

  In the first embodiment, the flow rate adjusting valve 33 as a bypass ratio adjusting device is provided in the inflow side piping 30 on the downstream side of the midway portion 30a of the inflow side piping 30 (connection portion of the bypass piping 32). Instead of the side pipe 30, the outflow side pipe 31 may be provided upstream of the mixing portion 31 a of the outflow side pipe 31.

  Alternatively, for example, a distribution valve configured to mechanically limit the bypass ratio R as a ratio of the tank side flow rate to the bypass side flow rate (= tank side flow rate / bypass side flow rate) to a range equal to or less than a predetermined maximum value. (A valve capable of distributing hot water flowing in from one inlet port to two outlet ports to flow out) is provided in the middle portion 30a of the inflow side piping 30 instead of the flow rate adjusting valve 33, or the bypass ratio R Of the mixing valve (a valve capable of mixing hot water flowing in from two inlet ports and flowing out from one outlet port) configured to be mechanically limited to a range below a predetermined maximum value. Instead of this, the mixing section 31a of the outflow side pipe 31 may be provided. The distribution valve or the mixing valve can be constituted by, for example, an electric three-way valve.

  In the first embodiment, for example, when the actual measured value of the bypass ratio Rx when the opening of the flow rate adjustment valve 33 is the fully opened opening is smaller than the reference value R0, the upper limit hot water storage The temperature Ttk_limH may be set to the same value as when the measured value of the bypass ratio Rx matches the reference value R0. Similarly, in the second embodiment, when the actual measured value of the bypass ratio Rx when the opening degree of the flow rate adjustment valve 33 is the fully opened degree is smaller than the reference value R0, the target hot water storage temperature Ttk_cmd (= Ttk_limH) may be set to the same value as when the measured value of the bypass ratio Rx matches the reference value R0.

  Further, when the bypass ratio Rx when the opening degree of the flow rate adjustment valve 33 is controlled to the opening degree of the fully opened state is different from the reference value R0 corresponding to the opening degree of the fully opened state, the opening degree of the flow rate adjusting valve 33 is set. Even in a state in which the opening degree is controlled to be slightly smaller than the opening degree in the fully opened state, the actual bypass ratio at the predetermined opening degree is equal to the bypass ratio Rx in the opening degree in the fully opening state of the flow regulating valve 33 and the above-described opening degree. It tends to be different from the design reference value corresponding to the predetermined opening degree in the same tendency as the relationship with the reference value R0. Therefore, for example, the bypass ratio measurement process is executed in a state where the opening degree of the flow rate adjustment valve 33 is controlled to a predetermined opening degree slightly smaller than the opening degree in the fully opened state, and the measured value of the bypass ratio is obtained by the measurement process. Accordingly, it is possible to change the upper limit hot water storage temperature Ttk_limH or the target hot water storage temperature Ttk_cmd.

  Moreover, in each said embodiment, the measurement process of bypass ratio Rx was performed at the time of the trial run of the immediate hot-water supply apparatus 20. FIG. However, even during the normal operation of the immediate hot water supply device 20, the bypass ratio measurement process is performed in a situation where the opening of the flow rate adjustment valve 33 is controlled to a fully opened position or a predetermined opening slightly smaller than that. May be executed.

  Further, in the first embodiment, not only the upper limit hot water storage temperature Ttk_limH but also the target hot water storage temperature Ttk_cmd are measured values of the actual bypass ratio Rx when the opening of the flow rate adjustment valve 33 is the fully open opening. You may make it change according to it. For example, when the measured value of the bypass ratio Rx is substantially equal to the reference value R0, the provisional value of the target hot water storage temperature Ttk_cmd calculated as described in the first embodiment (the difference between the measured value and the reference value R0 is sufficiently large). When the bypass ratio Rx is larger than the reference value R0 by a predetermined value or more, the provisional value of the target hot water storage temperature Ttk_cmd is set to a slightly smaller value than when Rx≈R0. In addition, when the bypass ratio Rx is smaller than the reference value R0 by a predetermined value or more, the provisional value of the target hot water storage temperature Ttk_cmd may be determined to be slightly larger than that when Rx≈R0.

  Further, in each of the above embodiments, in order to set the upper limit side incoming water temperature TinH used for determining the upper limit hot water storage temperature Ttk_limH, the immediate hot water controller 45 sets the set value of the hot water target temperature acquired through communication with the hot water controller 8. used. However, for example, when the hot water tap 1 is discharged (during the hot water discharge operation of the immediate hot water supply device 20), the detected value of the incoming water temperature Tin is increased to a steady temperature corresponding to the set value of the hot water supply target temperature. A detected value of the incoming water temperature Tin may be acquired, and the detected value may be used as information indicating the set value of the hot water supply target temperature used in the process of determining the upper limit hot water storage temperature Ttk_limH after the hot water operation. This is the same even when the immediate hot water target temperature Tout_cmd is determined according to the set value of the hot water supply target temperature.

  DESCRIPTION OF SYMBOLS 1 ... Hot water tap, 4 ... Heat source machine, 6 ... Hot-water supply pipe, 20 ... Immediate hot-water supply device, 21 ... Hot water storage tank, 22 ... Heater (heating device), 30 ... Inflow side piping, 31 ... Outflow side piping, 32 ... Bypass piping 33 ... Flow rate adjusting valve (bypass ratio adjusting device), 34, 39, 40 ... Temperature sensor, 46 ... Bypass ratio control unit, 47 ... Hot water storage temperature control unit, 48 ... Bypass ratio measurement unit.

Claims (4)

An inflow side pipe connected to the hot water supply pipe so that hot water heated by the heat source machine is supplied from the heat source machine via the hot water supply pipe, and the inflow side pipe so that hot water can be supplied from the inflow side pipe A hot water storage tank connected to the hot water storage tank, an outflow side pipe connected to the hot water storage tank and the hot water tap so that hot water in the hot water storage tank can be supplied to the hot water tap, and the hot water storage from the inflow side pipe to the outflow side pipe A bypass pipe connected between the inflow side pipe and the outflow side pipe so that hot water can flow without going through the tank, and a heating device for heating the hot water in the hot water storage tank are disposed near the hot water tap. The hot water flowing from the hot water supply pipe to the outflow side pipe through the inflow side pipe and the bypass pipe and the hot water flowing from the hot water storage tank to the outflow side pipe are mixed immediately after opening the hot water tap. Hot water A constructed immediately pouring device to supply from the outflow pipe to the tapping plug,
A tank-side flow rate that is a flow rate of hot water that flows from the inflow side piping to the outflow side piping through the hot water storage tank in the open state of the hot water tap, and the outflow side from the inflow side piping through the bypass piping A bypass ratio adjusting device that changes a bypass ratio that is a ratio with a bypass-side flow rate that is a flow rate of hot water flowing in the pipe;
A bypass ratio control unit for controlling the bypass ratio by controlling the operation of the bypass ratio adjusting device;
A hot water storage temperature control unit for controlling the hot water storage temperature, which is the temperature of the hot water in the hot water storage tank, by controlling the operation of the heating device;
A bypass in which the bypass ratio control unit measures an actual bypass ratio in a state where the control target of the bypass ratio is set to a predetermined value and the operation of the bypass ratio adjusting device is controlled according to the control target of the predetermined value. A ratio measurement unit,
The hot water storage temperature control unit measures at least one temperature of an upper limit hot water temperature that is an upper limit value of the hot water temperature used for controlling the hot water temperature and a target hot water temperature that is a target value of the hot water temperature. An immediate hot water supply device configured to change according to a measured value of the bypass ratio by a section. In the immediate hot water supply device according to claim 1,
When the bypass ratio is defined as a ratio of the tank side flow rate to the bypass side flow rate, the control target of the predetermined value is a control target for maximizing the bypass ratio realized by the bypass ratio adjusting device. ,
The hot water storage temperature control unit is configured so that an actual bypass ratio is a maximum realized by the bypass ratio adjusting device in a state where the actual hot water storage temperature is controlled to one of the upper limit hot water storage temperature and the target hot water storage temperature. When the bypass ratio is maintained, the measured value by the bypass ratio measurement unit so that the temperature of the hot water, which is the temperature of hot water supplied from the outflow side pipe to the hot water tap, remains at a temperature equal to or lower than a predetermined limit value. An immediate hot water supply device is configured to set the one of the temperatures using a water heater. In the instant hot water supply device according to claim 1 or 2,
When the bypass ratio is defined as a ratio of the tank side flow rate to the bypass side flow rate, the control target of the predetermined value is a control target for maximizing the bypass ratio realized by the bypass ratio adjusting device. ,
The hot water storage temperature control unit is configured to set the target hot water storage temperature to be higher as the measured value by the bypass ratio measurement unit is smaller. In the instant hot water supply apparatus of any one of Claims 1-3,
The heat source machine is a heat source machine that supplies hot water controlled to a preset hot water supply temperature to the hot water supply pipe.
The hot water storage temperature control unit can acquire information indicating a set value of the hot water supply target temperature, and uses the set value of the hot water target temperature indicated by the information and the measured value by the bypass ratio measuring unit. An immediate hot water supply apparatus configured to set one of an upper limit hot water storage temperature and a target hot water storage temperature.