JP2010261618A - Hot water storage type hot water supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hot water storage type hot water supply device for surely preventing abnormal high-temperature hot water supply that the hot water is supplied to a downstream side in a high temperature state, even when abnormality occurs due to, for example, failure of a mixing means for regulating a temperature by mixing hot water with supply water in supplying the hot water stored in a hot water storage tank. <P>SOLUTION: The water from a first bypass passage 44 is mixed with the hot water of high temperature supplied to an upstream-side hot water supply passage 51 from the hot water storage tank 3 with a prescribed mixing ratio by a mixing valve 7 to regulate its temperature, and the hot water is supplied to a downstream-side hot water supply passage 52. A flow rage adjustment valve 55, a meeting point 57 of a second bypass passage 8, a hot water supply temperature sensor 56, and a branch point 58 of a bath hot water tapping circuit 6 are disposed to the downstream-side hot water supply passage successively from an upstream side. When the hot water supply temperature is over an upper limit hot water supply temperature, an opening of the flow rate adjustment valve is changed to a small flow rate side by a controller 9, and a bypass opening/closing valve 81 is opened. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention is a cooling water exhaust heat such as a gas engine or a fuel cell, heat of a heat pump refrigerant, heat recovery from an external heat source such as solar energy of natural energy, or heating by energy consumption of an electric heater or the like, With regard to hot water storage water heaters that are configured to take out hot water from a hot water storage tank that has been stored at a predetermined high temperature, mix the water, adjust the temperature, and then supply hot water. The present invention relates to a technique that can reliably avoid the danger of hot hot water.

  Conventionally, in a water heater heated by an electric heater, the hot water discharged from the water heater is mixed with water and discharged from the faucet after the hot water temperature is lowered. It has been proposed that a water supply branch pipe is connected to the side, and the hot water temperature is lowered in advance before mixing hot water and water with water from this branch water supply pipe (see, for example, Patent Document 1). In other words, by lowering the hot water temperature to the middle stage before the original hot water / water mixing, even if the hot water / water mixing part breaks down and it becomes impossible to mix the water, The hot water is not discharged from the water heater.

  In addition, in a heat pump water heater that takes hot water from a hot water storage tank that is heated and stored by heat radiated with the operation of the heat pump and mixes it with the water supply in the mixing valve, the temperature is lowered to an appropriate temperature to supply hot water. There is known one in which a water supply bypass channel is connected to a hot water outlet at a downstream position (see, for example, Patent Document 2). A bypass opening / closing valve that is normally kept closed is interposed in this water supply bypass passage, and when the mixing valve becomes incapable of mixing due to a power outage or failure, the bypass opening / closing valve opens to open the water supply bypass flow path. The hot water is mixed with hot water passing through the mixing valve so as to avoid the situation where the hot water is supplied as it is.

JP 2003-222407 A JP 2006-125655 A

  However, the conventional hot water storage type hot water supply apparatus described above cannot sufficiently fulfill the function of avoiding the generation of high temperature hot water due to a failure of the mixing valve or the like, and it is considered that the risk of high temperature hot water still remains.

  That is, in the structural example described in Patent Document 2 illustrated in FIG. 4, the mixing valve 700 causes the hot water from the hot water storage tank 300 to pass through the hot water supply channel 500 due to the occurrence of a power failure or malfunction (failure). In the case of a water-impossible state, water from the bypass channel 800 is supplied to the downstream position of the mixing valve 700 by opening conversion of the bypass on-off valve 801, and the downstream side of the tap water channel 500 is mixed with this water. On the other hand, the reason that the situation that the hot water is discharged at the temperature in the hot water tank 300 can be avoided is the reason originally intended in Patent Document 2.

  However, the mixing valve 700 is fully open on the hot water tank 300 side, and the hot water passes through. That is, the fluid pressure at which all hot water flows through the hot water outlet 500 through the mixing valve 700 acts on the bottom of the hot water tank 300. The supply pressure of the water supplied from the bypass passage 800 to the tap water passage 500 is mainly based on the pressure loss at the solenoid valve that is the bypass on-off valve 801 and the like. The water pressure drops more than that. For this reason, the flow pressure on the side of the hot water flowing through the hot water outlet 500 is prevailed and mixing of the hot water from the bypass passage 800 does not effectively occur. As a result, most of the hot water that has passed through the mixing valve 700 in the failed state passes through. This means that the hot water is discharged downstream at the same temperature, that is, hot hot water is generated.

  The present invention has been made in view of such circumstances. The purpose of the present invention is to break down the mixing means for adjusting the temperature by mixing with hot water when using the hot water in the hot water storage tank for hot water supply, etc. A hot water storage type hot water supply device that can reliably prevent the occurrence of abnormally high temperature hot water that will be discharged downstream in the high temperature state even if an abnormality occurs due to It is to provide.

  In order to achieve the above object, in the first invention, a hot water storage tank for storing hot water in a predetermined high temperature state, an upstream hot water outlet connected to the top side of the hot water storage tank, and a bottom side of the hot water storage tank It is disposed at the junction of the connected water supply channel, the first bypass channel that branches from the middle of the water channel and merges with the upstream hot water discharge channel, and the junction between the first bypass channel and the upstream hot water discharge channel. Mixing means for adjusting the temperature to a predetermined temperature by mixing the water from the first bypass passage and the hot water from the upstream discharge passage in a variable mixing ratio, and the hot water adjusted by the mixing means to the outlet side The following specific items are provided for a hot water storage type hot water supply device having a downstream hot water outlet.

  That is, a flow rate adjusting valve that is disposed in a downstream side hot water discharge passage at a downstream position of the mixing means and changes and adjusts the outgoing hot water flow rate to the downstream side, and is branched from the water supply passage and downstream of the flow rate adjustment valve. A second bypass passage connected so as to merge with the downstream side hot water discharge passage of the side position, a bypass opening / closing valve interposed in the middle of the second bypass passage and switching the water supply to the downstream hot water supply passage so as to be openable and closable, An abnormality in the hot water temperature sensor that detects the temperature of the hot water at a position downstream of the joining point with respect to the downstream hot water outlet of the second bypass passage, and an abnormality through the downstream hot water outlet due to the occurrence of an abnormal situation in the mixing means. Control means for executing corresponding control for avoiding the occurrence of high temperature hot water is provided. And as the said control means, the hot water temperature detected by the said hot water temperature sensor is monitored, and when the hot water temperature exceeds the preset upper hot water temperature, the hot water flow rate which passes the said flow regulating valve is a smaller flow rate side. The switching operation is controlled so as to be changed to, and the opening and closing operation of the bypass on-off valve is controlled (claim 1).

  In the case of the present invention, when the hot water temperature detected by the hot water temperature sensor exceeds the upper limit hot water temperature, the corresponding control for avoiding the occurrence of abnormally high temperature hot water is performed by the control means, and the flow regulating valve is moved to the smaller flow rate side. In addition to being throttled, the bypass on-off valve is opened and switched to allow water supply from the water supply passage to join the downstream hot water supply passage through the second bypass passage. As a result, the hot water flow rate in the downstream side hot water path after passing through the flow rate adjusting valve is reduced to the smaller flow rate side, so that the supply of water from the second bypass path to the downstream side hot water path becomes smoother. For this reason, even if an abnormality occurs in which the hot water in the high temperature state passes through the mixing means from the upstream hot water outlet to the downstream hot water outlet, a higher mixing ratio is obtained with respect to hot water with a smaller flow rate. The feed water from the second bypass passage will be mixed, and the temperature of the tapping water will be greatly reduced. As a result, it is possible to reliably avoid occurrence of abnormally high temperature hot water on the downstream side.

  Further, in the second invention, a hot water storage tank for storing hot water in a predetermined high temperature state, an upstream hot water supply path connected to the top side of the hot water storage tank, and a water supply path connected to the bottom side of the hot water storage tank The first bypass passage that branches off from the middle of the water supply passage and merges with the upstream hot water discharge passage, and the junction between the first bypass passage and the upstream hot water discharge passage is provided from the first bypass passage. Mixing means for adjusting the temperature to a predetermined temperature by mixing water and hot water from the upstream side hot water discharge path in a variable mixing ratio; and a downstream hot water discharge path for discharging hot water adjusted by the mixing means to the downstream side The following specific items are provided for hot water storage hot water supply devices equipped with

  That is, a failure occurrence detection means for detecting the occurrence of an abnormal state of the mixing means, and a flow rate adjustment for changing and adjusting the downstream hot water flow rate disposed in the downstream hot water discharge passage at the downstream position of the mixing means. A valve, a second bypass passage that branches from the water supply passage and is joined to a downstream hot water discharge passage at a position downstream of the flow rate adjustment valve, and is interposed in the middle of the second bypass passage. A bypass on-off valve that switches the water supply to the downstream side hot water supply path so as to be openable and closable, and corresponding control to avoid the occurrence of abnormally high temperature hot water flow through the downstream side hot water supply path due to the occurrence of an abnormal situation in the mixing means. And a control means to be executed. Then, as the control means, when the failure occurrence detection means detects the occurrence of a failure in the mixing means, the switching operation control is performed so that the hot water flow rate passing through the flow rate adjustment valve is changed to the smaller flow rate side. The bypass on-off valve is controlled to be opened and closed (claim 2).

  In the case of the present invention, when a failure occurrence is detected in the mixing means by the failure occurrence detection means, it is determined that there is a possibility of occurrence of abnormally high temperature hot water, and corresponding control for avoiding the occurrence of abnormal high temperature hot water by the control means is performed. Executed. As in the first aspect of the invention, the flow control valve is throttled to a smaller flow rate side by this correspondence control, and the bypass on-off valve is opened and switched to supply water from the water supply passage through the second bypass passage to the downstream side hot water supply passage. It becomes possible to join. As a result, the hot water flow rate in the downstream side hot water path after passing through the flow rate adjusting valve is reduced to the smaller flow rate side, so that the supply of water from the second bypass path to the downstream side hot water path becomes smoother. For this reason, even if an abnormality occurs in which the hot water in the high temperature state passes through the mixing means from the upstream hot water outlet to the downstream hot water outlet, a higher mixing ratio is obtained with respect to hot water with a smaller flow rate. The feed water from the second bypass passage will be mixed, and the temperature of the tapping water will be greatly reduced. As a result, it is possible to reliably avoid occurrence of abnormally high temperature hot water on the downstream side.

  In the hot water storage type hot water supply apparatus of the above invention, a flow rate adjusting valve with a closing function can be used as the flow rate adjusting valve, and the flow rate adjusting valve can be controlled to be closed and switched as the corresponding control by the control means. In this case, the flow rate adjustment valve is closed and switched by corresponding control by the control means, and the outflow of hot water from the mixing means side to the downstream hot water outlet is completely blocked, while the downstream hot water outlet is closed. Thus, the water supply from the second bypass passage will flow in. This makes it possible to more reliably avoid the occurrence of abnormally high temperature hot water on the downstream side.

  Furthermore, a bath hot water circuit for pouring hot water, which has been temperature-controlled by the mixing means, into the bath tub is attached to the hot water storage hot water path of the invention, and the bath pouring circuit is connected to the hot water temperature sensor. It can connect so that it may branch from the downstream hot-water supply path of a downstream position rather than the detection position of the hot-water temperature by (Claim 4). In this case, if the possibility of occurrence of abnormally high temperature hot water is detected and the corresponding control is performed by the control means, the occurrence of abnormally high temperature hot water is surely avoided not only for hot water supply but also for pouring to the bathtub. It becomes possible to do.

  As described above, according to any one of the hot water storage hot water supply apparatuses according to claim 1, claim 3, and claim 4, the hot water temperature detected by the hot water temperature sensor exceeds the upper limit hot water temperature and When the possibility of occurrence is detected, corresponding control for avoiding the occurrence of abnormally high temperature hot water by the control means is executed, so that the hot water flow rate in the downstream hot water passage after passing through the flow regulating valve is smaller. Therefore, the supply of water from the second bypass passage to the downstream hot water discharge passage can be performed more smoothly. For this reason, even if an abnormality occurs in which the hot water in the high temperature state passes through the mixing means from the upstream hot water outlet to the downstream hot water outlet, a higher mixing ratio is obtained with respect to hot water with a smaller flow rate. The feed water from the second bypass passage can be mixed, and the temperature of the tapping water can be greatly reduced. As a result, it is possible to reliably avoid occurrence of abnormally high temperature hot water on the downstream side.

  According to the hot water storage type hot water supply apparatus of any one of claims 2, 3, and 4, there is a risk of occurrence of abnormally high temperature hot water when a failure occurrence is detected in the mixing means by the failure occurrence detection means. Determination is made and corresponding control for avoiding the occurrence of abnormally high temperature hot water by the control means is executed. By this correspondence control, the hot water flow rate in the downstream side hot water path after passing through the flow rate adjustment valve is reduced to the smaller flow rate side, so that the supply of water from the second bypass path to the downstream side hot water path is performed more smoothly. Will be able to. For this reason, even if an abnormality occurs in which the hot water in the high temperature state passes through the mixing means from the upstream hot water outlet to the downstream hot water outlet, a higher mixing ratio is obtained with respect to hot water with a smaller flow rate. The feed water from the second bypass passage can be mixed, and the temperature of the tapping water can be greatly reduced. As a result, it is possible to reliably avoid occurrence of abnormally high temperature hot water on the downstream side.

  In particular, according to the third aspect of the present invention, the outflow of hot water from the mixing means side to the downstream side hot water discharge path is completely blocked by controlling the closing switching operation as the corresponding control by the control means using the flow rate adjusting valve with a closing function. On the other hand, the water supply from the second bypass passage can be allowed to flow into the downstream hot water discharge passage. Thereby, generation | occurrence | production of the abnormally high temperature hot water to the downstream can be avoided still more reliably.

  Further, according to the fourth aspect of the present invention, it is connected so as to be branched from the downstream side hot water discharge passage at a position downstream from the detection position of the hot water temperature by the hot water temperature sensor so that the hot water can be poured into the bath hot water circuit. Therefore, when the possibility of occurrence of abnormally high temperature hot water is detected and the corresponding control is performed by the control means, the occurrence of abnormally high temperature hot water is ensured not only for hot water supply but also for pouring to the bathtub. Will be able to avoid.

It is a schematic diagram which shows embodiment of this invention. It is a block diagram for demonstrating mainly hot water supply control and abnormal high temperature response control of a controller. It is a table | surface which shows the test result done about the Example and the comparative example. It is a schematic diagram which shows the structural example of the hot water storage type hot-water supply apparatus contrasted in order to guide the subject which invention is going to solve.

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

  Reference numeral 2 in the figure denotes a heat recovery circuit for recovering heat from the exhaust heat of the engine cooling water of the gas engine 21 as an external heat source and storing it as hot water storage by exchanging heat with hot water in the hot water tank 3. A water supply circuit for supplying tap water, etc., 5 is a hot water discharge circuit for discharging hot water from the hot water storage tank 3 and supplying hot water to an unillustrated hot water tap, and 6 is branched from a downstream position of the hot water supply circuit 5 and poured into a bath tub. A bath pouring circuit for hot water, 7 is a mixing valve as mixing means for mixing hot water from the hot water storage tank 3 and water from the first bypass passage 44 described later at a predetermined mixing ratio, and 8 is branched from the water supply circuit 4. A second bypass passage 9 for bypassing the hot water storage tank 3 and supplying water to the hot water circuit 5 is a controller for controlling the operation of the hot water storage type hot water supply apparatus.

  The heat recovery circuit 2 exchanges heat for heat recovery in the gas engine 21 and the hot water tank 3 through the heat medium circulation path 22 using the engine coolant inside the gas engine 21 as a heat source heat medium by the operation of a circulation pump (not shown). It is constituted so that it may circulate between units (for example, coil type heat exchanger) 23. The hot water storage tank 3 is composed of a hermetic container, and the heat recovery circuit 2 is operated so that the internal hot water is heat exchange heated by the heat exchanger 23 and stored in a predetermined high temperature state.

  In the water supply circuit 4, the upstream end of the main water supply channel 41 is connected to an external water pipe or the like, and the downstream end is connected to the bottom 31 of the hot water tank 3. On the upstream side of the main water supply channel 41, a pressure reducing valve 42 is provided as a pressure reducing means for bringing the water supply source pressure into a predetermined pressure reducing state, and the hot water tank 3 is bypassed at the downstream branch point 43. The upstream end of the first bypass passage 44 for supplying water to the water introduction side of the mixing valve 7 is branched, and the upstream end of the second bypass passage 8 is branched at a branch point 45 upstream of the branch point 43. Yes. Further, a water supply temperature sensor 46 for detecting the water supply temperature and outputting it to the controller 9 is disposed at an appropriate place in the main water supply channel 41.

  The hot water circuit 5 discharges hot hot water from the top 32 of the hot water tank 3 and leads it to the hot water supply side of the mixing valve 7 and hot water derived after mixing by the mixing valve 7 to the hot water tap. And a downstream hot water discharge passage 52 for hot water discharge. A hot water storage temperature sensor 53 that detects the temperature of the hot water immediately after being taken out from the top 32 of the hot water storage tank 3 and outputs it to the controller 9 is interposed in the upstream hot water outlet 51, and a flow rate that passes through the downstream hot water outlet 52. Is detected and output to the controller 9, a flow rate adjusting valve 55 for changing and adjusting the hot water flow rate, and the temperature of the hot water discharged to the hot water tap or bath pouring circuit 6 is detected and the hot water temperature output to the controller. A sensor 56 is interposed. The flow rate adjusting valve 55 serves not only as an overflow prevention valve, but also plays a role in dealing with abnormally high temperatures as described later.

  The bath pouring circuit 6 has an upstream end branched from a branch point 58 located downstream of the hot water temperature sensor 56, and the downstream end is connected to a bath tub. The bath pouring circuit 6 has a pouring control in which the pouring valve 61 interposed at the downstream side pouring channel 52 side is controlled to open and close by the controller 9 to start and end pouring the bath. Is to be done.

  The mixing valve 7 has a predetermined mixing ratio (0 to 100%: 100 to 0%) with hot water taken out from the top 32 of the hot water tank 3 through the upstream side hot water outlet 51 and water supplied from the first bypass 44. The temperature of the mixture is adjusted to a predetermined temperature (for example, a set hot water supply temperature) by mixing, and then it is allowed to flow to the downstream side hot water supply passage 52.

  The second bypass passage 8 has an upstream end branched from the main water supply passage 41 at a branch point 45, and a downstream end at a junction point 57 at a position between the flow rate adjustment valve 55 of the downstream hot water discharge passage 52 and the hot water temperature sensor 56. It has come to join. That is, the second bypass path 8 is a position on the downstream side of the flow rate adjustment valve 55 and joins a position on the upstream side of the branch point 58 to the bath pouring circuit 6. The second bypass path 8 is normally shut off (closed state) by a bypass opening / closing valve 81 provided in the middle of the second bypass path 8, and when the controller 9 determines that an abnormality has occurred as will be described later, the second bypass path 8 is opened. Thus, water from the main water supply channel 41 is supplied to the junction 57 of the downstream hot water supply channel 52.

  The operation of the hot water storage type hot water supply apparatus described above is controlled by the controller 9 in response to the output of input setting signals and operation signals from the remote controller 91 and the output of detection signals from various temperature sensors 46, 53, 56, etc. It has come to be. The controller 9 includes an abnormally high temperature control unit 93 in addition to various control units such as a hot water supply control unit 92 (see FIG. 2) and a heat recovery control unit (not shown) for such operation control.

  Hereinafter, the hot water supply control by the hot water supply control unit 92 will be briefly described, and then the abnormal high temperature response control by the abnormal high temperature response control unit 93 characteristic of the present embodiment will be described.

  Hot water heated to a relatively high temperature (for example, 75 ° C.) by heat recovery control by the heat recovery control unit is stored in the hot water storage tank 3. That is, the heat recovery circuit 2 is operated and controlled, and heat is stored in the hot water tank 3 as hot water by exhaust heat recovery from the engine coolant.

  The hot water supply control by the hot water supply control unit 92 is performed as follows. That is, when the hot water tap is opened by the user, water is supplied from the main water supply channel 41 of the water supply circuit 4 to the bottom 31 of the hot water storage tank 3, and the hot water stored in the hot water storage tank 3 is pushed out from the top 32 by this water supply. Hot water is discharged to the mixing valve 7 through the passage 51. Then, the mixing ratio in the mixing valve 7 is set based on the detected values such as the hot water storage temperature from the hot water storage temperature sensor 53 and the water supply temperature from the water supply temperature sensor 46, and the water supply from the first bypass passage 44 in the mixing valve 7 After the temperature is adjusted to the set hot water supply temperature set in the remote controller 91, the hot water is discharged to the downstream hot water supply passage 52 and hot water is supplied to the hot water tap at the downstream end. Note that the mixing ratio may be feedback-controlled based on the hot water temperature from the hot water temperature sensor 56.

  The abnormally high temperature response control by the abnormally high temperature response control unit 93 is an occurrence of a situation in which abnormally high temperature hot water exceeding the upper limit hot water temperature flows to the hot water tap as it is due to some abnormality such as equipment failure of the mixing valve 7. This is control for avoiding the problem. The preset upper limit hot water temperature is a temperature value (for example, several degrees) in which a predetermined safety factor is expected from a temperature value that is assumed to be an abnormally high temperature hot water to be discharged to the hot water tap side. Is a temperature value set in advance by subtracting. The upper limit hot water temperature is set in advance as a fixed value for the hot water storage type hot water supply device, set at the time of installation before the start of service, or at the time of maintenance after the start of service, for example. It means changing and setting the set temperature value.

  Specifically, the abnormal high temperature response control unit 93 monitors the hot water temperature output from the hot water temperature sensor, and if it detects that the hot water temperature has changed above the upper limit hot water temperature, the occurrence of abnormal high temperature hot water is generated. It is determined that there is a risk, and the next response control is executed. That is, a switching command to the close side (small opening side or minimum opening) is issued to the flow rate adjusting valve 55 to change the hot water passage flow rate to a smaller flow rate side, and at the same time, the bypass opening / closing valve 81 is opened. The water from the main water supply passage 41 is supplied to the downstream hot water supply passage 52 at the junction 57 through the second bypass passage 8. Thereby, while the flow rate of the hot water flowing out to the downstream hot water outlet 52 through the mixing valve 7 in which an abnormality has occurred is reduced, the feed water flows into the downstream hot water outlet 52 through the second bypass path 8. Even if the hot water discharged from the top portion 32 of the hot water to the upstream side hot water discharge channel 51 is in a considerably high temperature state, the temperature can be drastically reduced by mixing the feed water flowing into the confluence 57, and there is a risk of the occurrence of abnormally high temperature hot water. Can be reliably avoided. That is, even if a failure occurs in the mixing valve 7 such that the hot water introduction side, which is the worst failure condition, is fixed in a fully opened state, the flow rate adjustment valve 55 reduces the passing flow rate as described above. Since the feed water from the 2 bypass passage 8 is mixed, the inflow of the feed water from the second bypass passage 8 to the downstream hot water discharge passage 52 can be performed more smoothly. For this reason, it is possible to mix the feed water from the second bypass passage at a higher mixing ratio with the hot water whose flow rate is adjusted to a smaller flow rate by the flow rate adjusting valve 55, and to greatly reduce the temperature of the hot water. become. As a result, the occurrence of abnormally high temperature hot water can be reliably avoided.

  Furthermore, since the junction 57 of the second bypass passage 8 is set at the upstream side position of the branch point 58 of the bath pouring circuit 6, if the possibility of occurrence of abnormally high temperature hot water is detected, In addition, the occurrence of abnormally high temperature hot water can be reliably avoided even for pouring.

<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 external heat source which is the object of the heat recovery which stores hot water in the hot water storage tank 3 was made into the gas engine (engine cooling water exhaust heat) was shown, not only this but as an external heat source, Solar heat (solar heat collection), fuel cell (cooling water exhaust heat), or heat pump (refrigerant exhaust heat) may be used to store hot water and store the heat. In this case, the present invention is applied. can do.

  In addition, heat storage by the heat recovery circuit 2 is performed by exchanging heat with hot water in the heat exchanger 23 installed in the hot water tank 3, but not limited to this, for example, hot water in the hot water tank 3 (hot water) ) From the bottom and return to the top, a heat storage circuit is installed, and heat is stored by performing liquid-liquid heat exchange with the heat source heat medium recovered by the heat recovery circuit in the middle of the heat storage circuit. Good.

  Furthermore, in the said embodiment, although what stored heat | fever as hot water storage with respect to the hot water storage tank 3 by waste heat recovery or heat recovery was shown, it heats previously by the heating means with energy consumption, such as an electric heater, for example. The present invention may be applied to hot water storage tanks that are stored in a predetermined high temperature state. In this case as well, the possibility of occurrence of abnormally high temperature hot water can be reliably avoided as in the above embodiment.

  In the above embodiment, the detection of the possibility of occurrence of abnormally high temperature is detected when the hot water temperature from the hot water temperature sensor is equal to or higher than the upper hot water temperature, but is not limited to this, for example, the hot water of the mixing valve 7 The occurrence of an abnormal state in which the motor (drive unit) that changes and adjusts the opening on the side is stuck at the fully open position even though the opening change command signal is output from the controller 9 to change the mixing ratio. The detection may be received in response to a detection signal from a limiter (failure occurrence detection means) relating to the driving position of the motor, and the detection of the possibility of occurrence of abnormally high temperature hot water may be performed by this detection. That is, if the failure of the mixing valve 7 is directly detected by the above limiter and the occurrence of the failure is detected, it is handled as detection of the possibility of occurrence of abnormally high temperature.

  You may make it use the thing with a closing function as the flow regulating valve 55 in the said embodiment. When a flow regulating valve with a closing function is used, the abnormally high temperature response control unit 93 outputs a fully closed switching operation command to the flow regulating valve when detecting the possibility of abnormally high temperatures. Thereby, the outflow of hot water from the side of the mixing valve 7 in the downstream side hot water supply passage 52 is completely blocked, while the hot water supply tap is supplied with water supplied from the second bypass passage 8 to the junction 57 as it is. Will be supplied.

  About the Example using the hot water storage type hot water supply apparatus of FIG. 1 explained in the above embodiment (however, the flow rate adjusting valve 55 has a closing function) and the comparative example using the hot water storage type hot water supply apparatus of the conventional structure of FIG. The mixing valves 7 and 700 are set in virtual failure states that the hot water introduction side is fully open and the water introduction side is fully closed, respectively, and the temperature of the hot water flowing downstream (detected by the hot water temperature sensors 56 and 501). A comparative test was conducted to see how the temperature was changed.

  In the case of the example, the abnormal high temperature countermeasure control described in the above embodiment, that is, the corresponding control of switching the flow rate adjustment valve 55 and switching the bypass opening / closing valve 81 to open is executed. On the other hand, in the case of the comparative example, the bypass on-off valve 801 was switched open.

  As preconditions, hot water having a hot water storage temperature of 75 ° C. was stored in the hot water storage tank 3,300, and the feed water temperature was set to three types of 5 ° C., 20 ° C., and 30 ° C. The test result about the tapping temperature in these three cases is shown in FIG.

  According to this, in the case of the comparative example, although the feed water is merged from the bypass channel 800, the temperature of the hot water having a temperature of 75 ° C. at the time of hot water storage is mixed with the water having the lowest feed water temperature of 5 ° C. Even so, the temperature of the tapping water decreased only to 48 ° C., and hereinafter, the tapping temperature was 53 ° C. when the feed water temperature was 20 ° C., and the tapping temperature was 58 ° C. when the feeding water temperature was 30 ° C. . That is, even if the bypass opening / closing valve 801 of the bypass path 8 is in the open state, the hot water from the hot water storage tank wins in the hot water path and mixing of the hot water of the hot water and the water of the supply water is not effectively performed. It is considered that even after mixing, the temperature could only be lowered to a higher temperature than when simple mixing was performed.

  On the other hand, in the case of the embodiment, when the feed water temperature is 5 ° C., the tapping temperature is 5 ° C., when the feed water temperature is 20 ° C., the tapping temperature is 20 ° C., and when the feed water temperature is 30 ° C., the tapping temperature is It turns out that it became 30 degreeC and the hot water was replaced by the water supplied from the bypass 8. This is a result of switching the downstream side hot water discharge path 52 to the shut-off state by the flow rate adjusting valve 55, but even if the switching operation is performed by reducing the passing flow rate to the small opening side without performing the closing switching operation, Since the flow rate of the hot water flowing out to the passage is reduced, the feed water from the bypass passage 8 is mixed more smoothly with less resistance, and as a result, the tapping temperature is considered to drop significantly to a temperature close to the feed water temperature. Thereby, compared with the case of said comparative example, in the case of an Example, the avoidance effect of abnormally high temperature hot water will be improved significantly.

3 Hot water tank 6 Bath pouring circuit 7 Mixing valve (mixing means)
8 Second bypass passage 9 Controller 41 Main water supply passage (water supply passage)
43 First bypass path branch point 44 First bypass path 45 Second bypass path branch point 51 Upstream side hot water path 52 Downstream side hot water path 55 Flow rate adjusting valve 56 Hot water temperature sensor 57 Second bypass path junction 58 Branch point 81 of hot water circuit Bypass on-off valve 93 Control unit for abnormally high temperature (control means)

Claims (4)

A hot water storage tank for storing hot water in a predetermined high temperature state, an upstream hot water supply path connected to the top side of the hot water storage tank, a water supply path connected to the bottom side of the hot water storage tank, and a branch from the middle of the water supply path Then, the first bypass passage that merges with the upstream hot water discharge passage, and the water from the first bypass passage and the upstream hot water discharge passage that are disposed at the junction of the first bypass passage and the upstream hot water discharge passage. A hot water storage type hot water supply apparatus comprising a mixing means for adjusting the temperature to a predetermined temperature by mixing the hot water of the hot water to a predetermined temperature and a downstream hot water outlet for discharging the hot water adjusted by the mixing means to the downstream side. There,
A flow rate adjusting valve disposed in the downstream side hot water discharge passage at the downstream side position of the mixing means for changing and adjusting the outgoing hot water flow rate to the downstream side;
A second bypass passage branched from the water supply passage and connected to join a downstream hot water discharge passage at a position downstream of the flow rate adjustment valve;
A bypass on-off valve that is interposed in the middle of the second bypass path and switches the water supply to the downstream hot water supply path so that it can be opened and closed;
A tapping temperature sensor that detects a tapping temperature at a position downstream of the junction with the downstream tapping path of the second bypass path;
Control means for executing corresponding control for avoiding the occurrence of abnormally high temperature hot water through the downstream side hot water outlet due to the occurrence of an abnormal situation in the mixing means,
The control means monitors the tapping temperature detected by the tapping temperature sensor, and when the tapping temperature exceeds a preset upper tapping temperature, the tapping flow rate passing through the flow rate adjustment valve is changed to a smaller flow rate side. A hot water storage type hot water supply apparatus configured to perform switching operation control as described above and to perform open switching operation control on the bypass on-off valve. A hot water storage tank for storing hot water in a predetermined high temperature state, an upstream hot water supply path connected to the top side of the hot water storage tank, a water supply path connected to the bottom side of the hot water storage tank, and a branch from the middle of the water supply path Then, the first bypass passage that merges with the upstream hot water discharge passage, and the water from the first bypass passage and the upstream hot water discharge passage that are disposed at the junction of the first bypass passage and the upstream hot water discharge passage. A hot water storage type hot water supply apparatus comprising a mixing means for adjusting the temperature to a predetermined temperature by mixing the hot water of the hot water to a predetermined temperature and a downstream hot water outlet for discharging the hot water adjusted by the mixing means to the downstream side. There,
A failure occurrence detection means for detecting the occurrence of an abnormal state of the mixing means;
A flow rate adjusting valve disposed in the downstream side hot water discharge passage at the downstream side position of the mixing means for changing and adjusting the outgoing hot water flow rate to the downstream side;
A second bypass passage branched from the water supply passage and connected to join a downstream hot water discharge passage at a position downstream of the flow rate adjustment valve;
A bypass on-off valve that is interposed in the middle of the second bypass path and switches the water supply to the downstream hot water supply path so that it can be opened and closed;
Control means for executing corresponding control for avoiding the occurrence of abnormally high temperature hot water through the downstream side hot water outlet due to the occurrence of an abnormal situation in the mixing means,
The control means controls the switching operation so that the tapping flow rate passing through the flow rate adjustment valve is changed to a smaller flow rate side when the failure occurrence detection is detected by the failure occurrence detection means. A hot water storage type hot water supply apparatus configured to control opening and closing of a bypass on-off valve. The hot water storage type hot water supply apparatus according to claim 1 or 2,
The hot water storage type hot water supply device, wherein the flow rate adjusting valve is configured by a flow rate adjusting valve with a closing function, and is configured to control the switching operation of the flow rate adjusting valve as a corresponding control by the control means. The hot water storage type hot water supply path according to any one of claims 1 to 3,
A bath discharge circuit is provided for pouring hot water, which has been temperature-controlled by the mixing means, into the bath tub. The bath pouring circuit is located downstream of the position where the hot water temperature is detected by the hot water temperature sensor. A hot water storage type hot water supply apparatus that is connected so as to branch from a downstream hot water outlet.

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