JP2013113522A - Storage type hot water supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a storage type hot water supply system that can supply hot water of a temperature near a hot water supply set temperature even when a hot water supply mixing valve is failed.SOLUTION: When abnormality in a hot water supply temperature is detected, a mixing ratio of hot water and water in the hot water supply mixing valve 52 is determined, a hot water storage temperature T to make the hot water supply temperature from the hot water supply mixing valve 52 under the determined mixing rate, be equal to the hot water supply set temperature, is calculated, and the hot water supply temperature after mixing the hot water discharged from the hot water storage tank 2 and the water by the hot water supply mixing valve 52, is controlled to the hot water supply set temperature, by adjusting a temperature of the hot water stored in a hot water storage tank 2 to the calculated hot water storage temperature T.

Description

  The present invention relates to a hot water storage type hot water supply system.

  Conventional hot water storage type hot water supply systems, for example, as disclosed in Patent Documents 1 to 3 below, store hot water heated by a heat source such as a heat pump or a gas engine in a hot water storage tank, and store the hot water in the hot water storage tank. The hot water stored in the hot water is discharged from the hot water stored in the hot water tank, or the hot water stored in the hot water tank is used as a heat exchange medium to indirectly heat the hot water supplied from the water supply circuit with the high temperature hot water. By mixing the water from the water supply circuit connected to the water supply with a hot water mixing valve controlled by a microcomputer, the hot water temperature after mixing is configured to be a preset hot water temperature set by the user. Yes.

  In this hot water storage type hot water supply system, various proposals have been conventionally made in order to prevent unexpected hot water from being supplied due to an abnormality in the hot water mixing valve.

  For example, Patent Document 1 includes an abnormality detection means for detecting an abnormality in the hot water supply temperature from the hot water mixing valve, and when the abnormality detection means determines that an abnormality has occurred, the hot water storage temperature in the hot water storage tank is set to the hot water supply set temperature. A technique is disclosed in which the hot water supply temperature from the hot water supply mixing valve is set to be lower than at least the hot water supply set temperature by setting (see paragraph number 0020 of Patent Document 1).

  Further, Patent Document 2 is provided with a bypass flow path for water supply from the water intake channel to bypass the hot water supply mixing valve, and a high temperature avoidance valve (bypass valve) for opening and closing the bypass flow path. By opening the bypass flow path, the hot water discharged from the hot water storage tank and a sufficient amount of water are mixed without going through the hot water mixing valve. A technique for preventing hot water from being supplied is disclosed.

  Patent Document 3 discloses that a relatively low temperature hot water at the lower part of the hot water tank is circulated and supplied to the upper part of the hot water tank while the heat source is stopped when an abnormality in the hot water temperature is detected. A technique is disclosed in which the temperature of the hot water stored is lowered.

JP 2001-90965 A JP 2006-125655 A JP 2007-240091 A

  None of the above Patent Documents 1 to 3 can prevent unexpectedly hot water from being supplied, but the hot water supply temperature from the hot water supply mixing valve becomes the hot water supply set temperature set by the user. Was not guaranteed, and warm water lower than the preset hot water temperature was supplied. That is, most of the malfunctions of the hot water mixing valve are caused by sticking of sliding parts such as the valve body, but the hot water temperature is below the set hot water temperature even at the fixing position where the mixing ratio of hot water from the hot water storage tank is the largest. Therefore, in the case of a failure at a fixed position where the mixing ratio of hot water is small, the difference between the hot water set temperature and the actual hot water temperature becomes large, and only hot water can be supplied. In spite of the presence of high-temperature water, there is a problem that it becomes a hot water supply with a lukewarm water temperature that cannot be used for showers and the like.

  Then, an object of this invention is to provide the hot water storage type hot-water supply system which can supply hot water at the temperature close | similar to hot-water supply preset temperature, even at the time of failure of the hot-water supply mixing valve.

  In order to achieve the above object, the present invention takes the following technical means.

  That is, the present invention includes a heat source unit, a hot water storage tank for storing hot water heated by the heat source unit, a hot water mixing valve for mixing and supplying hot water discharged from the hot water storage tank, and hot water after mixing. In the hot water storage hot water supply system comprising a mixing valve control means for controlling the hot water mixing valve so that the temperature becomes a hot water supply set temperature, and an abnormality detecting means for detecting an abnormality in the hot water temperature from the hot water mixing valve, the abnormality Determining means for determining the mixing ratio of hot water and water in the hot water mixing valve when the detecting means detects an abnormality in the hot water temperature, and the hot water temperature from the hot water mixing valve at the mixing ratio determined by the determining means Hot water storage temperature calculating means for calculating a hot water storage temperature as a set temperature, and hot water storage temperature adjusting means for adjusting the hot water temperature stored in the hot water storage tank to the hot water storage temperature calculated by the hot water storage temperature calculating means, A shall (claim 1).

  According to the hot water storage type hot water supply system of the present invention, normally, high temperature hot water (for example, 80 ° C. or more) heated in the heat source section is supplied to the hot water storage tank, and the high temperature hot water has a low specific gravity, so the upper side of the hot water storage tank The hot water is stored, and a relatively low temperature hot water is stored in the lower part of the hot water tank. The hot water stored in the upper part of the hot water tank is discharged from the hot water itself, or the hot water stored in the hot water tank is used as a heat exchange medium to indirectly heat the hot water from the water supply circuit to the hot water to be discharged and discharged. The hot water mixing valve controlled by the mixing valve control means is mixed with the water from the water supply circuit to mix the hot water from the hot water mixing valve to the hot water tap and other appropriate hot water supply objects at a hot water set temperature preset by the user or manufacturer. Hot water is supplied. When the abnormality detection means detects an abnormality in the hot water supply temperature from the hot water supply mixing valve based on a predetermined determination criterion such as a state where the difference between the actual hot water supply temperature and the hot water supply set temperature is a predetermined temperature or more continues for a predetermined time or more, Since there is a high possibility that the hot water mixing valve has failed and stuck at a predetermined mixing ratio position, the actual mixing ratio of hot water and water in the hot water mixing valve at the time of abnormality detection is determined by the determining means, The hot water storage temperature at which the hot water supply temperature from the hot water mixing valve at the determined mixing ratio becomes the hot water set temperature is calculated by the hot water storage temperature calculation means, and the hot water temperature stored in the hot water tank is calculated by the hot water storage temperature adjustment means. Adjust to. As a result, after the abnormality is detected, hot water at the calculated hot water storage temperature is stored in the hot water tank, so that the hot water discharged from the hot water tank is supplied with a hot water mixing valve that has failed and stuck. When mixed with water from the hot water, hot water is supplied at a temperature close to the hot water supply set temperature. In addition, when an abnormality is detected by the abnormality detection means, it is preferable to warn the user of the occurrence of an abnormality by an alarm display or the like, and to urge replacement or repair of the hot water supply mixing valve.

  Preferably, the determining means determines the mixing ratio based on the temperature of hot water and water mixed by the hot water mixing valve and the hot water temperature after mixing, but the hot water supplied to the hot water mixing valve The mixing ratio can be determined based on the respective flow rates of water and water.

  The hot water storage temperature calculated by the hot water storage temperature calculating means can be calculated based on the temperature of the water supplied from the water supply circuit, the hot water supply set temperature, and the mixing ratio determined by the determining means, and heat loss due to the piping configuration etc. It is also possible to calculate in consideration of. In addition, in the case of a system configuration in which hot water stored in a hot water tank is used as a heat exchange medium and the hot water is indirectly heated by the hot water and discharged, the relationship between the hot water temperature and the hot water temperature is obtained by testing. It is possible to calibrate the hot water temperature based on the test data.

  Preferably, the hot water storage temperature adjusting means adjusts the hot water temperature supplied from the heat source part to the hot water storage temperature calculated by the hot water temperature calculating means by adjusting the output of the heat source part. The present invention can be configured only by changing the control method using the piping configuration of the hot water storage type hot water supply system as it is. However, the present invention is not limited to such a configuration. For example, the temperature of hot water stored in the hot water storage tank is adjusted by mixing a controlled amount of water with hot water heated by the heat source unit. It is also possible to configure.

  In the hot water storage type hot water supply system of the present invention, a high temperature avoidance valve that opens and closes a flow path for supplying and mixing water to the hot water supply from the hot water supply mixing valve, and the high temperature avoidance valve when the abnormality detection means detects an abnormality. High temperature avoidance valve control means for performing opening control and closing control of the high temperature avoidance valve after hot water is stored in the hot water storage tank at the hot water storage temperature calculated by the hot water storage temperature calculation means (claim). 2). The basic configuration of this high temperature avoidance valve is also described in Patent Document 2 above, but the feature of the present invention is that the hot water storage temperature is calculated by the hot water storage temperature calculation means by the high temperature avoidance valve control means. The high temperature avoidance valve is controlled to be closed after the hot water is stored in the tank. With this feature, while the temperature of the hot water discharged from the hot water storage tank after the abnormality is detected is still high, the high temperature hot water can be reliably prevented from being supplied by opening the high temperature avoidance valve. The high temperature hot water in the upper part of the tank is discharged to some extent or the temperature drops due to heat exchange with the water supplied from the water supply circuit, and hot water is stored in the hot water storage tank at the calculated hot water storage temperature, and then the high temperature avoidance valve is closed. As a result, hot water is automatically supplied at the hot water supply set temperature after hot water is stored in the hot water storage tank at the calculated hot water storage temperature.

  As described above, according to the hot water storage type hot water supply system according to claim 1 of the present invention, a state where the difference between the actual hot water supply temperature and the hot water supply set temperature is a predetermined temperature or more continues for a predetermined time or longer. Based on the determination criteria, when the abnormality detection means detects an abnormality in the hot water supply temperature from the hot water supply mixing valve, the determination means determines the actual mixing ratio of hot water and water in the hot water supply mixing valve at the time of the abnormality detection. The hot water storage temperature at which the hot water supply temperature from the hot water supply mixing valve becomes the hot water set temperature is calculated by the hot water storage temperature setting means, and the hot water temperature stored in the hot water tank is adjusted to the hot water storage temperature calculated by the hot water temperature adjustment means. As a result, after the abnormality is detected, hot water at the calculated hot water storage temperature is stored in the hot water storage tank, so that the hot water discharged from the hot water storage tank is damaged and stuck. Mixing valve By being mixed with water from the water supply circuit, it is possible to perform hot-water supply temperature close to the hot water set temperature.

  Moreover, according to the hot water storage type hot water supply system according to claim 2 of the present invention, high temperature hot water can be obtained by opening the high temperature avoidance valve while the temperature of the hot water discharged from the hot water storage tank after the abnormality detection is still high. While reliably preventing hot water from being supplied, the high temperature hot water in the upper part of the hot water tank is discharged to some extent or the temperature drops due to heat exchange with the water supplied from the water supply circuit, and at the calculated hot water storage temperature. By closing the high temperature avoidance valve after hot water has been stored in the hot water tank, hot water can be automatically supplied at the set hot water temperature after hot water has been stored in the hot water tank at the calculated hot water temperature. it can.

1 is an overall schematic configuration diagram of a hot water storage hot water supply system according to an embodiment of the present invention. It is a control flowchart at the time of abnormality detection of the hot water supply temperature of the hot water storage type hot water supply system.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings.

  FIG. 1 schematically shows a hot water storage type hot water supply system according to an embodiment of the present invention. The hot water storage type hot water supply system includes an external heat source 1 (heat source unit) configured by a heat pump, a gas engine, and the like, and the external heat source 1. A hot water tank 2 for storing hot water heated by the water, a heat storage circulation circuit 3 for heating by the external heat source 1 while taking out the hot water in the hot water tank 2 from the bottom and returning it to the top, and supplying tap water and the like from the outside A hot water supply circuit 4 for supplying hot water to a hot-water tap (not shown) using hot water supplied from the hot water storage tank 2, and a bath reheating circuit that uses hot water supplied from the hot water storage tank 2 as a heat source. 6, a bath dropping hot water supply circuit 7 for branching from the hot water supply circuit 5 to supply hot water to the bathtub, and a controller (not shown) composed of a microcomputer or the like for controlling the operation of the hot water storage hot water supply system.

  The external heat source 1 is configured to be able to adjust and control the hot water temperature to the hot water tank 2 by a controller. The external heat source 1 includes an incoming water temperature sensor (not shown) that detects the incoming water temperature from the bottom of the hot water tank 2, and an outgoing water temperature sensor (not shown) that detects the outgoing water temperature to the top of the hot water tank 2. Is provided.

  The hot water storage tank 2 is configured in a hermetically sealed manner, and is provided with a remaining hot water amount sensor composed of a plurality of temperature sensors 21 disposed at a plurality of positions in the height direction including at least the top position on each side portion. The hot water temperature of the hot water stored in the hot water storage tank 2 can be detected, whereby the amount of hot water stored in the hot water storage tank 2 can be detected from the upper side.

  The heat storage circulation circuit 3 is arranged to take out the relatively low temperature hot water in the hot water tank 2 from the bottom of the hot water tank 2, pass through the external heat source 1, and return it to the top of the hot water tank 2. A circulation pump 31 is interposed in the heat storage circuit 3 between the bottom of the hot water tank 2 and the external heat source 1. It should be noted that immediately after the operation of the external heat source 1 is started, relatively low temperature hot water is supplied from the external heat source 1, but if such low temperature hot water is supplied to the top of the hot water tank 2, the high temperature hot water on the upper side of the hot water tank 2 drops in temperature. Therefore, until the hot water temperature from the external heat source 1 reaches a predetermined temperature or more, the external heat source is connected to the bottom of the hot water tank 2 through the bypass path 33 connected to the downstream side of the heat storage circuit 3 via the three-way switching valve 32. The hot water from 1 is supplied.

  The upstream end of the water supply circuit 4 is connected to an external water pipe or the like, and is branched into a main water supply channel 41 and a mixed water supply channel 42. The main water supply channel 41 has a downstream end connected to the bottom of the hot water tank 2 so that tap water is supplied to the bottom of the hot water tank 2 as the hot water in the hot water tank 2 is discharged from the top. It is configured. The mixed water supply passage 42 is connected to a hot water supply mixing valve 52 (described later) of the hot water supply circuit 5 so that water can be supplied. In addition, the water supply which detects the temperature of the water supplied by the pressure reducing valve 43, the check valve 44, and the water supply circuit 4 in the water supply circuit 4 on the upstream side of the branch portion between the main water supply channel 41 and the mixed water supply channel 42. A temperature sensor 45 is provided.

  The hot water supply circuit 5 includes a hot water supply passage 51 connected at the upstream end to the top of the hot water storage tank 2 and the downstream end extending to the hot water tap, and a hot water supply mixing valve 52 provided in the middle of the hot water supply passage 51. The hot water supply amount sensor 53, the hot water supply temperature sensor 54, the hot water supply amount adjustment valve 55, and the hot water supply valve 52 are arranged at the upstream position of the hot water mixing valve 52 and discharged from the hot water tank 2. And a hot water temperature sensor 58 for detecting the hot water temperature immediately after. The hot water supply mixing valve 52 mixes the hot water supplied from the upstream side of the hot water supply channel 51 and the water supplied from the mixed water supply channel 42 at a controlled mixing ratio (mixed water), so that the user can remotely control the hot water. The temperature is adjusted to a hot water supply set temperature set by the above method, and hot water is supplied to the hot water tap. The hot water supply temperature sensor 54 detects the temperature of the hot water finally supplied after temperature control and outputs it to the controller. Based on the output from the hot water supply temperature sensor 54, the hot water supply mixing valve 52 Feedback control is performed by the controller.

  In addition, a bypass flow path 56 that connects the mixed water supply water path 42 and the hot water supply path 51 on the downstream side of the hot water supply mixing valve 52, and a high-temperature avoidance valve 57 that includes an electromagnetic on-off valve that opens and closes the bypass flow path 56. By opening the high temperature avoidance valve 57, a sufficient amount of water for avoiding high temperature hot water can be supplied and mixed with the hot water supplied from the hot water supply mixing valve 52. The high temperature avoidance valve 57 is also controlled by a controller, and the controller functions as a high temperature avoidance valve control means. The high temperature avoidance valve 57 is configured to be closed when energized and to be opened when not energized. With this, the hot avoidance valve 57 is automatically opened at the time of a power failure so that hot water is supplied at the time of a power failure. The hot water is prevented from being heated.

  The bath reheating circuit 6 operates the reheating pump 61 to circulate hot water in a bathtub (not shown) through the recirculation circuit 62 and the heat exchanger 63, and in the heat exchanger 63 Reheating is performed by liquid-liquid heat exchange. On the heat source side of the heat exchanger 63, hot water discharged from the top of the hot water tank 2 through the heat source supply path 64 branched from the hot water supply path 51 on the upstream side of the hot water mixing valve 52 is replenished as a heat source for reheating the bath. Hot water supplied by a heat source pump 66 and having a temperature drop due to liquid-liquid heat exchange is circulated and supplied to the bottom of the hot water tank 2 through a check valve 65. In the reheating circulation path 62, a water level sensor 62a, a water flow switch 62b, a bath return temperature sensor 62c, and a reheating temperature sensor 62d are provided.

  The bath dropping hot water supply circuit 7 connects the hot water supply passage 51 downstream of the hot water supply mixing valve 52 and the recirculation circulation path 62 to drop the hot water supply from the hot water supply mixing valve 52 and pour it into the circulation passage 62. A passage 71, a water amount sensor 72, a pouring electromagnetic valve 73, a drop temperature sensor 74, and a water amount adjustment valve 75 are provided.

  The operation of each of the circuits 3 to 7 is controlled by the controller in response to the output of input setting signals and operation signals from the remote controller and the output of detection signals from various temperature sensors and water amount sensors. It has become. Hereinafter, characteristic control of the present invention will be described in detail.

  In the hot water storage type hot water supply system according to the present embodiment, based on the hot water supply set temperature set by the remote controller and the temperature detected by the hot water supply temperature sensor 54, as in the technique disclosed in the above-mentioned Patent Document 1 by the applicant of the present application. The controller is configured such that the controller detects an abnormality in the hot water supply temperature on the condition that a state where the temperature difference is, for example, 10 ° C. or more has continued for a predetermined time, and the hot water supply temperature from the hot water supply mixing valve 52 is detected by the controller. An abnormality detection means (hot water / mixture abnormality detection means) for detecting the abnormality is configured. The abnormality detection means may be configured to detect an abnormality when the mixing ratio determined by the determination means described later is a ratio at which high-temperature hot water having a predetermined temperature or higher is expected.

  When the abnormality of the hot water supply temperature is detected by the abnormality detection means, the controller interrupts the hot water storage control of the normal hot water (for example, 80 ° C. or more), and the medium temperature hot water (for example, 60 ° C.) by the abnormality detection control shown in FIG. Degree) hot water storage control. When this abnormality detection control is started, first, the mixing ratio of hot water and water in the hot water mixing valve 52 is calculated and determined based on the detected values of the hot water temperature sensor 58, the hot water temperature sensor 45, and the hot water temperature sensor 54. (Step S1). The controller that performs such determination constitutes determination means for determining the mixing ratio of hot water and water in the hot water supply mixing valve 52 when the abnormality detection means detects an abnormality in the hot water temperature.

  Next, based on the calculated mixing ratio, the detected value of the feed water temperature sensor 45, and the hot water supply set temperature, the controller sets the hot water supply set temperature when mixed with the feed water from the water supply path 42 at the above mix ratio. The temperature of hot water is calculated (step S2). The controller for performing the calculation calculates the hot water storage temperature T (for example, about 60 ° C.) at which the hot water supply temperature from the hot water mixing valve 52 becomes the hot water supply set temperature (for example, 42 ° C.) at the mixing ratio determined by the determination means. Calculation means is configured.

  Next, the controller controls the opening of the high temperature avoidance valve 57 in order to avoid the relatively hot water being supplied until the high temperature hot water in the upper part of the hot water tank 2 is consumed (step S3). A sufficient amount of water supply is supplied to the hot water supply channel 51 to maintain the hot water supply temperature at a relatively low temperature. It should be noted that the high temperature avoidance valve 57 may be one that is controlled to be opened immediately when a high temperature hot water abnormality is detected, and the process of step S3 may be executed before the process of step S1.

  In this state, until the amount of hot water stored in the upper part of the hot water tank 2 decreases below a certain level, for example, until the uppermost temperature sensor 21 constituting the remaining hot water amount sensor no longer detects high temperature, The hot water storage operation by the heat source 1 is not performed, and the open state of the high temperature avoidance valve 57 is maintained. Therefore, even if the hot water tap is opened at this time, low temperature warm water is supplied.

  When the remaining hot water amount sensor detects that the amount of hot water in the hot water tank 2 has decreased below a certain level (step S4), the controller starts operation of the external heat source 1 with the hot water temperature T calculated in step S2 ( Step S5). More specifically, the controller controls the output of the external heat source 1 so that the hot water temperature from the external heat source 1 becomes the hot water storage temperature T, whereby the hot water of the hot water storage temperature T is transferred from the external heat source 1 to the hot water tank 2. The hot water is supplied to the top and stored in the hot water tank 2. At this time, even if the hot water remains slightly in the upper part of the hot water tank 2, the hot water is diffused by mixing with the hot water. The controller for controlling the output of the external heat source 1 constitutes hot water storage temperature adjusting means for adjusting the hot water temperature stored in the hot water storage tank 2 from the external heat source 1 to the hot water storage temperature T.

  Next, when the hot water of the hot water storage temperature T is stored in the upper part of the hot water tank 2 by a preset amount (step S6), the controller controls the closing of the high temperature avoidance valve 57 (step S7), and an external heat source. The operation of No. 1 is temporarily stopped (step S8), and the abnormality detection control is thereby ended. The high temperature avoidance valve 57 is maintained in an open state while high temperature hot water remains in the hot water storage tank 2 and there is a possibility of high temperature hot water, and high temperature hot water in the hot water storage tank 2 is consumed. Since it may be closed at any time after the disappearance, the process of step S7 may be executed immediately after the process of step 4.

  Thereafter, until the hot water mixing valve 52 is repaired or replaced, the hot water storage operation control is continued. When the remaining amount of the hot water in the hot water storage tank 2 is reduced, the external heat source 1 is operated and the intermediate hot water is operated. To store hot water.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed in design. For example, in the above-described embodiment, the hot water or the medium hot water stored in the hot water tank 2 is discharged from the top of the hot water tank 2, but the hot water stored in the hot water tank 2 is used as a heat exchange medium. It is also possible to apply to a hot water storage hot water supply system in which the hot water supplied from the hot water is circulated through a heat exchange pipe in the hot water tank 2 and heated, and the heated hot water is discharged. Further, the external heat source 1 may be anything as long as it can change the temperature of the hot water. In addition, even when a hot water temperature that cannot be varied is adopted as the external heat source 1, the hot water storage temperature T calculated by mixing a controlled amount of water supply in the circulation path between the external heat source 1 and the hot water tank 2. You may comprise so that hot water storage may be performed. Further, a built-in heat source attached to the hot water tank 2 may be used as the heat source 1.

DESCRIPTION OF SYMBOLS 1 Heat source part 2 Hot water storage tank 52 Hot-water supply mixing valve 57 High temperature avoidance valve

Claims (2)

A heat source section, a hot water storage tank for storing hot water heated in the heat source section, a hot water supply mixing valve for mixing and supplying hot water discharged from the hot water storage tank, and a hot water supply temperature after mixing is a hot water supply set temperature In a hot water storage type hot water supply system comprising a mixing valve control means for controlling the hot water mixing valve and an abnormality detection means for detecting an abnormality in hot water temperature from the hot water mixing valve,
Determining means for determining a mixing ratio of hot water and water in the hot water supply mixing valve when the abnormality detecting means detects an abnormality in the hot water supply temperature; Hot water storage temperature calculating means for calculating the hot water storage temperature as the hot water supply set temperature, and hot water storage temperature adjusting means for adjusting the hot water temperature stored in the hot water storage tank to the hot water storage temperature calculated by the hot water storage temperature calculating means. A hot water storage type hot water supply system.   2. The hot water storage hot water supply system according to claim 1, wherein a high temperature avoidance valve that opens and closes a flow path for supplying and mixing water to the hot water supply from the hot water supply mixing valve, and the high temperature avoidance when the abnormality detection means detects an abnormality. High temperature avoidance valve control means for controlling opening of the valve and closing control of the high temperature avoidance valve after hot water is stored in the hot water storage tank at the hot water storage temperature calculated by the hot water storage temperature calculation means. Hot water storage hot water system.

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