JP2007071450A

JP2007071450A - Hot water storage type water heater

Info

Publication number: JP2007071450A
Application number: JP2005258799A
Authority: JP
Inventors: Shigemi Fujii; 繁美藤井; Shigeru Murakami; 村上　　茂
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2005-09-07
Filing date: 2005-09-07
Publication date: 2007-03-22

Abstract

<P>PROBLEM TO BE SOLVED: To improve safety and COP by utilizing water of intermediate temperature with priority and preventing outflow of contamination in an intermediate-temperature water use inhibition mode. <P>SOLUTION: When the intermediate-temperature water use inhibition mode is judged by an intermediate part temperature detecting means 136 and an upper part temperature detecting means 137, a first mixing valve 120 is kept in a water-side full open state, mixing control thereafter is inhibited, and the control inhibition state of the first mixing valve 120 is released to recover normal operation when the completion of total volume boiling-up operation is confirmed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、貯湯式給湯装置に関するものであり、特に、電動式混合弁を用いた湯水混合制御に関するものである。 The present invention relates to a hot water storage type hot water supply apparatus, and particularly to hot water mixing control using an electric mixing valve.

従来、この種の貯湯式給湯装置は、ヒートポンプ回路で加熱された湯水を貯湯タンクの上部から成層状態で貯湯し、その貯湯された湯水を上部出湯管より取り出し給水管から供給される水と混合して所定の湯温に調節して給湯端末等の負荷側に供給するようにしていた。また、近年、この貯湯水を用いて風呂の追い焚きや暖房に利用する機能を有した貯湯式給湯装置が注目されるようになってきた。しかし、この場合、風呂の追い焚きや暖房に利用した後の温度の低下した湯水は再度貯湯タンク内に回収されるため、貯湯タンク内部には上部の高温水の下方に中温水と呼ばれる中途半端な温度の湯水が多量に蓄えられることになる。この中温水が蓄えられた状態で全量沸き上げ動作が行われると、ヒートポンプ回路への入水温度が高い状態でヒートポンプサイクルの加熱動作が行われるため、効率の悪い、いわゆるＣＯＰの低い沸き上げ動作となる。 Conventionally, this type of hot water storage type hot water supply device stores hot water heated by a heat pump circuit in a stratified state from the upper part of the hot water storage tank, and the hot water stored in the hot water storage tank is taken out from the upper hot water discharge pipe and mixed with the water supplied from the water supply pipe. Then, it is adjusted to a predetermined hot water temperature and supplied to a load side such as a hot water supply terminal. Further, in recent years, hot water storage type hot water supply devices having a function of using this hot water storage for bathing and heating are drawing attention. However, in this case, the hot water whose temperature has dropped after being used for bathing or heating is collected again in the hot water storage tank, so the hot water inside the hot water tank is called halfway hot water below the upper hot water. A large amount of hot and cold water will be stored. When the whole amount boiling operation is performed in a state where the medium-temperature water is stored, the heating operation of the heat pump cycle is performed in a state where the incoming water temperature to the heat pump circuit is high. Become.

そこで、この対策として特許文献１に開示されているように、貯湯タンクの中間部に中温水の取り出し口を設け、この取り出し口より取り出された中温水と上部出湯管より取り出された高温水を混合して所定の湯温を確保し、さらに、この混合水と給水管より供給される水を混合することで設定温度の湯水を精度よく得るようにしていた。この方法によれば中温水を積極的に取り出すことができるため、貯湯タンク下方には低温水を確保することができるとともに、貯湯タンク上方の高温水の使用を最小限に抑えることができ、高ＣＯＰの沸き上げ動作と湯切れ現象の抑制を図ることができるものである。
特開２００３−２４０３４２号公報 Therefore, as disclosed in Patent Document 1, as disclosed in Patent Document 1, an intermediate temperature water outlet is provided in the middle portion of the hot water storage tank, and the intermediate temperature water extracted from the outlet and the high temperature water extracted from the upper outlet pipe are disposed. A predetermined hot water temperature is ensured by mixing, and the mixed water and water supplied from a water supply pipe are mixed to obtain hot water at a set temperature with high accuracy. According to this method, the medium-temperature water can be actively taken out, so that low-temperature water can be secured below the hot water tank, and the use of high-temperature water above the hot water tank can be minimized. It is possible to suppress the boiling operation of the COP and the phenomenon of running out of hot water.
JP 2003-240342 A

しかしながら、上記従来の構成によれば、ヒートポンプ回路を用いた給湯装置において、中温水の沸き上げ性能への影響を排除するため優先的に中温水を利用する手段を設けたことにより、貯湯タンク下方には低温水を確保することができるとともに、貯湯タンク上方の高温水の使用を最小限に抑えることができ、高ＣＯＰの沸き上げ動作と湯切れ現象の抑制を図ることができ、ヒートポンプ式給湯装置の湯水利用形態としては極めて有効な手段ではあるが、一方、貯湯タンク内の湯水の利用量が極端に少ない、または全く使用されない等の状況において貯湯タンク内の湯水の利用が長時間停滞し、貯湯タンク内の湯水の温度が低下してくると、雑菌の繁殖が起こる恐れがあり、特に、レジオネラ菌が繁殖すると人体に危害を及ぼす恐れがある。このレジオネラ菌は湯温が２５℃〜５０℃の範囲で活発に活動し、この湯温範囲は上記使用湯量が極端に少ない状態において貯湯タンクの下部で発生しやすい現象となる。このような状態において中温水の利用手段を用いて湯水を供給すると繁殖したレジオネラ菌等の雑菌を積極的に利用側端末に供給することになり、衛生面で課題を有するものであった。 However, according to the above conventional configuration, in the hot water supply apparatus using the heat pump circuit, by providing means for using the medium temperature water preferentially in order to eliminate the influence on the boiling performance of the medium temperature water, Can secure low-temperature water, minimize the use of high-temperature water above the hot water storage tank, and can control the boiling operation of high COP and the phenomenon of running out of hot water. Although this is an extremely effective means of using hot water in the equipment, the use of hot water in the hot water storage tank has been stagnant for a long time in situations where the hot water usage in the hot water storage tank is extremely small or not used at all. If the temperature of hot water in the hot water storage tank decreases, miscellaneous germs may grow.In particular, Legionella germs may harm the human body. . This Legionella bacterium is actively active in the range of hot water temperature of 25 ° C. to 50 ° C., and this hot water temperature range is a phenomenon that tends to occur in the lower part of the hot water storage tank when the amount of hot water used is extremely small. In such a state, if hot water is supplied using the means for using medium-temperature water, the proliferated bacteria such as Legionella bacteria are actively supplied to the user terminal, which has a problem in terms of hygiene.

本発明は、上記従来の課題を解決するもので、ヒートポンプ式給湯装置の湯水利用形態として極めて有効な手段である中温水を優先的に使用可能な湯水混合制御方法を提供しつつ、貯湯タンク内の湯水の利用量が極端に少ない等の状況で湯水の利用が停滞したときの安全性を確保した貯湯式給湯装置の提供を目的とするものである。 The present invention solves the above-described conventional problems, and provides a hot and cold water mixing control method capable of preferentially using medium-temperature water, which is an extremely effective means for using hot water in a heat pump type hot water supply apparatus, The purpose of the present invention is to provide a hot water storage type hot water supply device that ensures safety when the use of hot water stagnate in situations where the amount of hot water used is extremely small.

上記従来の課題を解決するために、本発明の貯湯式給湯装置は、ヒートポンプ回路を用いて加熱した湯水をタンク上部から成層状態で貯湯しその湯水を利用して端末側に所望の湯水を供給する貯湯式給湯装置において、タンク上部の湯水を取り出す出湯管と、タンクの略中間部の湯水を取り出す中温出湯管と、タンク下部に水道水を供給する給水管と、前記中温出湯管近傍のタンク内湯温を検出する中部温度検出手段と、前記中温出湯管と上部出湯管の間のタンク内湯温を検出する上部温度検出手段と、前記給水管と前記中温出湯管からの湯水を混合する第１混合弁と、前記第１混合弁からの湯水と前記出湯管からの高温水を混合し所定温度の湯水を端末側に供給する利用側混合弁と、前記第１混合弁と利用側混合弁の弁開度制御を行う制御部とを備え、全量沸き上げ運転を行う時間帯を設定するとともに、湯量不足を判断したとき湯切れ沸き上げ運転を行うことを設定した貯湯式給湯装置であって、前記制御部は、全量沸き上げ運転を行う時間帯に前記中部温度検出手段で検出される湯温が中温水の有無を判断する第１設定温度以上あり、かつ、前記上部温度検出手段で検出される湯温が使用状況を判断する第２設定温度を一度も下回っていないとき中温水使用禁止モードと判断し、前記第１混合弁の制御を禁止するようにしたものである。 In order to solve the above-mentioned conventional problems, the hot water storage type hot water supply apparatus of the present invention stores hot water heated using a heat pump circuit in a stratified state from the upper part of the tank and supplies desired hot water to the terminal side using the hot water. A hot water storage pipe for taking out hot water at the upper part of the tank, a medium temperature hot water pipe for taking out hot water at a substantially intermediate part of the tank, a water supply pipe for supplying tap water to the lower part of the tank, and a tank near the intermediate temperature hot water supply pipe A middle temperature detecting means for detecting the temperature of the internal hot water, an upper temperature detecting means for detecting the temperature of the hot water in the tank between the intermediate temperature hot water pipe and the upper hot water pipe, and a first water for mixing the hot water from the water supply pipe and the intermediate temperature hot water pipe. A mixing valve, a use side mixing valve that mixes hot water from the first mixing valve and hot water from the outlet pipe and supplies hot water at a predetermined temperature to the terminal side, and a first mixing valve and a use side mixing valve. Control for valve opening control A hot water storage hot water supply device that sets a time zone for performing a full-boiling operation and sets a hot-water boiling operation when it is determined that the amount of hot water is insufficient. The hot water temperature detected by the middle temperature detecting means during the operation time period is equal to or higher than a first set temperature for judging the presence or absence of intermediate temperature water, and the hot water temperature detected by the upper temperature detecting means determines the use situation. When the temperature is not lower than the second set temperature, it is determined as the medium hot water use prohibition mode, and the control of the first mixing valve is prohibited.

上記発明によれば、中部温度検出手段で貯湯タンク内に中温水が存在するか否かを判断し、上部温度検出手段で貯湯タンク上部の高温水が使用され湯水の入れ替え現象が発生したか否かを判断し、前記両者の判断結果より貯湯タンク内の湯水の利用量が少なく、貯湯タンク下方において中温以下の湯水が長時間停滞した後の湯水利用形態として、中温出湯管からの湯水供給を行わないように第１混合弁の制御を禁止するようにしているため、中温水が存在し、かつ湯水の利用量が少なく貯湯タンク内の湯水が停滞し、貯湯タンク下部で温度低下が起こってレジオネラ菌等の雑菌が繁殖したとしても、貯湯タンク上部の比較的高温の湯水から利用することができ、雑菌の影響を受けることなく湯水供給が可能となる。 According to the above invention, it is determined whether or not intermediate temperature water exists in the hot water storage tank by the intermediate temperature detection means, and whether or not a hot water replacement phenomenon has occurred by using the high temperature water at the upper part of the hot water storage tank by the upper temperature detection means. As a hot water usage form after the amount of hot water in the hot water storage tank is less than the result of both judgments, and hot water of medium temperature or lower stays in the lower part of the hot water tank for a long time, hot water is supplied from the medium temperature hot water pipe. Since the control of the first mixing valve is prohibited so that it does not occur, there is medium hot water, the amount of hot water used is low, the hot water in the hot water tank is stagnant, and the temperature drops at the lower part of the hot water tank Even if miscellaneous bacteria such as Legionella propagate, they can be used from the relatively hot water in the upper part of the hot water storage tank, and hot water can be supplied without being affected by the bacteria.

本発明の貯湯式給湯装置は、ヒートポンプ式給湯装置の湯水利用形態として極めて有効な手段である中温水を優先的に使用可能な湯水混合制御方法を提供しつつ、貯湯タンク内の湯水の利用量が極端に少ない等の状況で湯水の利用が停滞したときの安全性を確保した貯湯式給湯装置を提供することができる。 The hot water storage type hot water supply apparatus of the present invention provides a hot water mixing control method capable of preferentially using medium hot water, which is a very effective means as a hot water use form of a heat pump type hot water supply apparatus, and uses the amount of hot water in the hot water storage tank. Therefore, it is possible to provide a hot water storage type hot water supply apparatus that ensures safety when the use of hot water is stagnant in a situation where the amount of water is extremely small.

第１の発明は、ヒートポンプ回路を用いて加熱した湯水をタンク上部から成層状態で貯湯しその湯水を利用して端末側に所望の湯水を供給する貯湯式給湯装置において、タンク上部の湯水を取り出す出湯管と、タンクの略中間部の湯水を取り出す中温出湯管と、タンク下部に水道水を供給する給水管と、前記中温出湯管近傍のタンク内湯温を検出する中部温度検出手段と、前記中温出湯管と上部出湯管の間のタンク内湯温を検出する上部温度検出手段と、前記給水管と前記中温出湯管からの湯水を混合する第１混合弁と、前記第１混合弁からの湯水と前記出湯管からの高温水を混合し所定温度の湯水を端末側に供給する利用側混合弁と、前記第１混合弁と利用側混合弁の弁開度制御を行う制御部とを備え、全量沸き上げ運転を行う時間帯を設定するとともに、湯量不足を判断したとき湯切れ沸き上げ運転を行うことを設定した貯湯式給湯装置であって、前記制御部は、全量沸き上げ運転を行う時間帯に前記中部温度検出手段で検出される湯温が中温水の有無を判断する第１設定温度以上あり、かつ、前記上部温度検出手段で検出される湯温が使用状況を判断する第２設定温度を一度も下回っていないとき中温水使用禁止モードと判断し、前記第１混合弁の制御を禁止するようにしたことを特徴とするものである。 A first invention is a hot water storage type hot water supply apparatus that stores hot water heated using a heat pump circuit in a stratified state from the upper part of a tank and supplies the desired hot water to the terminal side using the hot water. A tapping pipe, a medium temperature tapping pipe for taking out hot water at a substantially middle part of the tank, a water supply pipe for supplying tap water to the bottom of the tank, a middle temperature detecting means for detecting the temperature of the hot water in the tank near the middle temperature tapping pipe, and the medium temperature An upper temperature detecting means for detecting the hot water temperature in the tank between the hot water outlet pipe and the upper hot water outlet pipe, a first mixing valve for mixing hot water from the water supply pipe and the intermediate temperature hot water pipe, and hot water from the first mixing valve; A use-side mixing valve that mixes high-temperature water from the outlet pipe and supplies hot water at a predetermined temperature to the terminal side, and a controller that controls the opening degree of the first mixing valve and the use-side mixing valve, Set a time zone for boiling operation In addition, the hot water storage type hot water supply apparatus is set to perform the hot water boiling operation when it is determined that the amount of hot water is insufficient, and the control unit is detected by the middle temperature detection means during the time period for performing the full water heating operation. When the hot water temperature is equal to or higher than the first set temperature for determining the presence or absence of intermediate temperature water, and the hot water temperature detected by the upper temperature detection means has never been lower than the second set temperature for determining the use status The use prohibit mode is determined, and the control of the first mixing valve is prohibited.

そして、中部温度検出手段で貯湯タンク内に中温水が存在するか否かを判断し、上部温度検出手段で貯湯タンク上部の高温水が使用され湯水の入れ替え現象が発生したか否かを判断し、前記両者の判断結果より貯湯タンク内の湯水の利用量が少なく、貯湯タンク下方
において中温以下の湯水が長時間停滞した後の湯水利用形態として、中温出湯管からの湯水供給を行わないように第１混合弁の制御を禁止するようにしているため、中温水が存在し、かつ湯水の利用量が少なく貯湯タンク内の湯水が停滞し、貯湯タンク下部で温度低下が起こってレジオネラ菌等の雑菌が繁殖したとしても、貯湯タンク上部の比較的高温の湯水から利用することができ、雑菌の影響を受けることなく湯水供給が可能となる。 Then, the middle temperature detecting means determines whether or not the medium temperature water exists in the hot water storage tank, and the upper temperature detecting means determines whether or not the hot water replacement phenomenon has occurred due to the use of the high temperature water in the upper part of the hot water storage tank. As a result of the above judgment, the amount of hot water in the hot water storage tank is small, and hot water supply from the intermediate temperature hot water pipe is not performed as a hot water usage form after the hot water of medium temperature or lower has stagnated for a long time below the hot water storage tank. Since the control of the first mixing valve is prohibited, there is medium-temperature water, the amount of hot water used is low, the hot water in the hot water tank is stagnant, the temperature drops at the bottom of the hot water tank, and Legionella bacteria, etc. Even if miscellaneous bacteria propagate, it can be used from the relatively hot water at the upper part of the hot water storage tank, and hot water can be supplied without being affected by the miscellaneous bacteria.

第２の発明は、制御部は中温水使用禁止モードになったとき、第１混合弁を水側全開状態とし、中温出湯管からの湯水供給を禁止するようにしたことを特徴とするものである。 The second aspect of the invention is characterized in that, when the control unit is in the medium warm water use prohibition mode, the first mixing valve is in the water side fully open state and the hot water supply from the medium temperature hot water pipe is prohibited. is there.

そして、中温水が存在し、かつ湯水の利用量が少ない中温水使用禁止モードになったときは、タンク上部の出湯管からのみ湯水を供給するように第１混合弁を水側全開状態としているため、貯湯タンク下部で繁殖した雑菌が利用側端末に供給されることを抑制するとができる。つまり、雑菌が繁殖しやすい温度分布となる貯湯タンク下部に近い中温出湯管からの湯水供給を禁止するようにしているため、雑菌が利用側端末に供給されることがなく、中温出湯管より上の雑菌が繁殖しにくい比較的高温の湯水を利用して利用側混合弁により所望の湯温に調節して使用することで所定量の湯水を確保することができる。 And when medium temperature water exists and it becomes the medium temperature water use prohibition mode with little use amount of hot water, the 1st mixing valve is made into the water side full open state so that hot water may be supplied only from the tap pipe of the tank upper part For this reason, it is possible to suppress the supply of miscellaneous bacteria propagated in the lower part of the hot water storage tank to the user terminal. In other words, the hot water supply from the intermediate hot water pipe near the lower part of the hot water storage tank, where the temperature distribution is easy for breeding of bacteria, is prohibited. A predetermined amount of hot and cold water can be ensured by using a relatively high temperature hot water that is difficult for the bacteria to propagate and adjusting to a desired hot water temperature using a use-side mixing valve.

第３の発明は、制御部は中温水使用禁止モードになったとき、予め定めた沸き上げ条件で全量沸き上げ運転の完了が確認されたとき、第１混合弁の制御禁止を解除するようにしたことを特徴とするものである。 According to a third aspect of the present invention, when the control unit is in the medium hot water use prohibition mode, when the completion of the full-boiling operation is confirmed under a predetermined boiling condition, the control prohibition of the first mixing valve is canceled. It is characterized by that.

そして、中温水使用禁止モードと判断された後の深夜時間帯に貯湯タンクの全量が沸き上げられ、貯湯タンク下部の湯温が雑菌が死滅する温度、例えば６５℃になると、通常の湯水混合制御を行うように復帰させているため、中温水が存在し、かつ湯水の利用量が極端に少ない期間中に繁殖した雑菌は死滅し、その後、安全な状態で中温水を優先的に利用する湯水混合制御により効果的な湯水供給を行うことができる。 Then, when the total amount of the hot water storage tank is boiled up in the midnight time zone after it is determined that the medium hot water use prohibition mode has been reached, and the hot water temperature at the bottom of the hot water storage tank reaches a temperature at which various germs die, for example, 65 ° C., normal hot water mixing control Therefore, the germs that have propagated during periods when the amount of hot water used is extremely low and the amount of hot water used is extremely low will be killed, and then hot water will preferentially use the hot water in a safe state. Effective hot water supply can be performed by mixing control.

第４の発明は、制御部は中温水使用禁止モードになったとき、最初の全量沸き上げ運転の時間帯が経過した後の湯切れ沸き上げ運転を行う時間帯になってから、第１混合弁の制御禁止を解除するようにしたことを特徴とするものである。 In the fourth aspect of the invention, when the control unit enters the medium hot water use prohibition mode, the first mixing is performed after the time period for performing the hot water boiling operation after the first full amount boiling operation time period has elapsed. This is characterized in that the prohibition of control of the valve is released.

そして、中温水使用禁止モードになったときは、その後最初の夜間時間帯が経過した後の昼間時間帯になってから、第１混合弁の制御禁止を解除するようにしたもので、中温水使用禁止モード中は第１混合弁の制御を禁止して中温出湯管からの湯水の供給を禁止するため、中温水が存在し、かつ湯水の利用量が極端に少ない期間中に貯湯タンク下部に繁殖したレジオネラ菌等の雑菌の流出を防止することができ、夜間時間帯を経過することで貯湯タンク下部の湯水を含むタンク全量をレジオネラ菌が死滅する６５℃以上の湯温に沸き上げることができ、この全量沸き上げ運転の時間帯を経過した後に第１混合弁の制御を用いて湯水混合制御を行うことで、レジオネラ菌等の雑菌が存在しない状態で効果的な湯水利用形態を確保することができる。 Then, when the medium warm water use prohibition mode is entered, the control of the first mixing valve is canceled after the daytime period after the first night time period has elapsed. During the use prohibition mode, the control of the first mixing valve is prohibited and the supply of hot water from the intermediate temperature hot water pipe is prohibited, so that there is medium temperature water and the amount of hot water used is extremely low at the bottom of the hot water tank. It is possible to prevent outflow of various bacteria such as Legionella that have propagated, and to heat up the entire tank, including hot water at the bottom of the hot water storage tank, to a hot water temperature of 65 ° C. or higher at which Legionella dies. It is possible to ensure an effective hot water usage form in the absence of miscellaneous bacteria such as Legionella bacteria by performing hot water mixing control using the control of the first mixing valve after the time period of this total boiling operation has passed. It is possible .

以下、本発明の実施の形態について、図面を参照しながら説明する。なお、この実施の形態によって本発明が限定されるものではない。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

（実施の形態１）
図１は、本発明の第１の実施の形態における貯湯式給湯装置の構成図である。 (Embodiment 1)
FIG. 1 is a configuration diagram of a hot water storage type hot water supply apparatus according to a first embodiment of the present invention.

貯湯タンク１０１には下部と上部を連通させた沸き上げ配管１０２を設け、その途中に沸き上げポンプ１０３と熱交換器１０４を配設している。この沸き上げ経路によって貯湯タンク１０１下部の水は、沸き上げポンプ１０３によって熱交換器１０４に導かれ、その
熱交換器１０４を通過する過程で加熱されて湯となり、貯湯タンク１０１上部に導かれる。貯湯タンク１０１に供給された湯は貯湯タンク１０１内でその比重差から湯が上部、水が下部に分離し、湯が押し下げられる形で層を成して蓄積される。貯湯タンク１０１内の湯が使用されると、それに伴い給水管１０５から貯湯タンク１０１内に水が給水され、貯湯タンク１０１内には使用状況に応じて減量した高温の湯が上部に、給水管１０５より供給された水が下部に分離した状態で貯留される。 The hot water storage tank 101 is provided with a boiling pipe 102 in which the lower part and the upper part are communicated with each other, and a boiling pump 103 and a heat exchanger 104 are arranged in the middle. The water in the lower part of the hot water storage tank 101 is guided to the heat exchanger 104 by the boiling pump 103 through this boiling path, and heated in the process of passing through the heat exchanger 104 to become hot water, and is guided to the upper part of the hot water storage tank 101. The hot water supplied to the hot water storage tank 101 is stored in the hot water storage tank 101 in layers in such a manner that the hot water is separated into the upper part and the water is separated into the lower part due to the difference in specific gravity. When the hot water in the hot water storage tank 101 is used, water is supplied from the water supply pipe 105 into the hot water storage tank 101, and the hot water reduced in accordance with the use state is placed in the hot water storage tank 101 at the upper part. The water supplied from 105 is stored in a separated state at the bottom.

また、熱交換器１０４の熱源となるヒートポンプ回路１０６は、圧縮機１０７、膨張弁１０８、ファン１０９による強制空冷式の蒸発器１１０で構成され、冷媒として二酸化炭素を用い、高圧側では臨界圧を越える状態で運転することで９０℃に近い高温水を貯湯することができるとともに、レジオネラ菌などを考慮した６５℃程度の温水の貯湯は高いＣＯＰで行うことができるものである。 The heat pump circuit 106 serving as a heat source for the heat exchanger 104 is composed of a compressor 107, an expansion valve 108, and a forced air-cooled evaporator 110 using a fan 109. Carbon dioxide is used as a refrigerant, and a critical pressure is set on the high-pressure side. It is possible to store hot water close to 90 ° C. by operating in a temperature exceeding that, and hot water storing about 65 ° C. considering Legionella bacteria can be performed at a high COP.

次に、貯湯タンク１０１内の湯水を負荷側に供給するための利用側回路構成について説明すると、貯湯タンク１０１の上部には高温水を取り出す出湯管１１１を設け、この出湯管１１１と給水管１０５の略中間部には中温水を取り出す中間出湯管１１２を設けている。 Next, a use side circuit configuration for supplying hot water in the hot water storage tank 101 to the load side will be described. A hot water discharge pipe 111 for taking out high temperature water is provided at the upper part of the hot water storage tank 101, and the hot water discharge pipe 111 and the water supply pipe 105 are provided. An intermediate hot water discharge pipe 112 for taking out the medium-temperature water is provided at a substantially intermediate portion.

出湯管１１１からは浴槽１１３の湯水と熱交換して追い焚き動作を行うための風呂熱交換器１１４と接続し循環ポンプ１１５を介して貯湯タンク１０１の下部に接続した風呂利用回路１１６が設けられており、前記風呂熱交換器１１４の二次側には浴槽１１３の風呂アダプター１１７と接続し風呂ポンプ１１８により浴槽水を循環させるための風呂循環回路１１９が構成されている。上記構成により、貯湯タンク１０１の上部より供給された高温水は風呂熱交換器１１４で風呂循環回路１１９を流れる浴槽水と熱交換され温度低下した後、中温水となって貯湯タンク１０１に戻される。この風呂追い焚き動作が継続すると貯湯タンク１０１内は上部の高温水の量が減少しその下方に蓄積される中温水の量が増大する。この中温水の増大現象は種々の弊害を招き、大きくは沸き上げ動作時におけるヒートポンプ回路１０６の運転効率（ＣＯＰ）の低下に関与する。すなわち、貯湯タンク１０１の下部に中温水が増加すると沸き上げ時の熱交換器１０４の入水温度が高い状態でヒートポンプ回路１０６の冷媒と熱交換することになり、冷媒と温水との温度差が減少して加熱能力が低下する。特に、冷媒として二酸化炭素を用いたヒートポンプサイクルにあっては、ヒートポンプの高圧側圧力が高いため入水温度が高くなるとヒートポンプの運転効率（ＣＯＰ）の低下度合いが顕著となる。 A bath utilization circuit 116 connected to a lower part of the hot water storage tank 101 through a circulation pump 115 is provided from the hot water outlet pipe 111 to a bath heat exchanger 114 for exchanging heat with hot water in the bathtub 113 and performing a reheating operation. On the secondary side of the bath heat exchanger 114, a bath circulation circuit 119 is connected to the bath adapter 117 of the bathtub 113 and the bath pump 118 circulates the bath water. With the above configuration, the hot water supplied from the upper part of the hot water storage tank 101 is heat-exchanged with the bath water flowing through the bath circulation circuit 119 by the bath heat exchanger 114 and the temperature is lowered, and then returned to the hot water storage tank 101 as intermediate hot water. . If this bath chasing operation continues, the amount of high-temperature water in the upper part of the hot water storage tank 101 decreases and the amount of medium-temperature water accumulated below it increases. This increase phenomenon of intermediate temperature water causes various adverse effects, and is largely related to a decrease in the operating efficiency (COP) of the heat pump circuit 106 during the boiling operation. That is, when the medium temperature water is increased in the lower part of the hot water storage tank 101, heat exchange with the refrigerant of the heat pump circuit 106 is performed in a state where the incoming water temperature of the heat exchanger 104 at the time of boiling is high, and the temperature difference between the refrigerant and the hot water decreases. Heating capacity is reduced. In particular, in a heat pump cycle using carbon dioxide as a refrigerant, since the high-pressure side pressure of the heat pump is high, the degree of decrease in the operating efficiency (COP) of the heat pump becomes significant when the incoming water temperature increases.

さらに、中温水が増加することは、貯湯タンク１０１の上部高温水が減少することであり、全体として貯湯能力が低下することになり、湯量不足につながるものでもある。 Further, the increase in the medium-temperature water means that the high-temperature water in the upper part of the hot water storage tank 101 is reduced, and the hot water storage capacity is lowered as a whole, leading to a shortage of hot water.

そこで、本実施の形態ではこの中温水対策として、貯湯タンク１０１の略中間部に中間出湯管１１２を設け、この中間出湯管１１２と給水管１０５より供給される湯水を混合し所定の混合水を得るための第１混合弁１２０を設け、第１温度検出器１２１で検出される湯温をフィードバックすることで弁開度の調節を行い所定の目標温度を確保するようにしている。この第１混合弁１２０を設けたことにより、使用目的に応じた湯温を中温水を優先的に取り出すことが可能となり、貯湯タンク１０１内の中温水を減少させることができる。 Therefore, in the present embodiment, as a countermeasure against this warm water, an intermediate hot water pipe 112 is provided at a substantially intermediate portion of the hot water storage tank 101, and hot water supplied from the intermediate hot water pipe 112 and the water supply pipe 105 is mixed to obtain a predetermined mixed water. A first mixing valve 120 for obtaining the temperature is provided and the valve opening degree is adjusted by feeding back the hot water temperature detected by the first temperature detector 121 to ensure a predetermined target temperature. By providing the first mixing valve 120, it is possible to preferentially take out the hot water according to the purpose of use, and the hot water in the hot water storage tank 101 can be reduced.

前記第１混合弁１２０の出力側には用途に応じた負荷側回路が構成され、まず給湯利用として、第１混合弁１２０からの混合水と出湯管１１１からの高温水とを混合し設定温度の湯水を得るための負荷側混合弁の１つである給湯混合弁１２２を設け、カラン１２４に供給するようにしている。この給湯混合弁１２２の出力側には給湯温度検出器１２３が取り付けられ、給湯温度検出器１２３で検出される湯温をフィードバックすることで弁開度
の調節を行い設定温度を確保するようにしている。 On the output side of the first mixing valve 120, a load-side circuit is configured according to the application. First, as hot water use, the mixed water from the first mixing valve 120 and the high-temperature water from the outlet pipe 111 are mixed and set to a set temperature. A hot water supply mixing valve 122 which is one of the load side mixing valves for obtaining hot water is provided and supplied to the currant 124. A hot water temperature detector 123 is attached to the output side of the hot water mixing valve 122, and the valve opening is adjusted by feeding back the hot water temperature detected by the hot water temperature detector 123 so as to ensure a set temperature. Yes.

また、風呂利用としては、第１混合弁１２０からの混合水と出湯管１１１からの高温水とを混合し設定温度の湯水を得るための負荷側混合弁の１つである風呂混合弁１２５を設け、注湯弁１２６を介して風呂循環回路１１９に接続し浴槽１１３への湯張りを行うようにしている。この風呂混合弁１２５の出力側には風呂温度検出器１２７が取り付けられ、風呂温度検出器１２７で検出される湯温をフィードバックすることで弁開度の調節を行い設定温度を確保するようにしている。 For bath use, a bath mixing valve 125, which is one of the load side mixing valves for mixing the mixed water from the first mixing valve 120 and the high temperature water from the outlet pipe 111 to obtain hot water at a set temperature, is used. It is provided and connected to the bath circulation circuit 119 via the pouring valve 126 to fill the bathtub 113 with hot water. A bath temperature detector 127 is attached to the output side of the bath mixing valve 125. By adjusting the valve opening by feeding back the hot water temperature detected by the bath temperature detector 127, the set temperature is secured. Yes.

なお、第１混合弁１２０の中温水側供給経路には逆止弁１２８を設け、中間出湯管１１２からの中温水の逆流を防止するようにしている。また、給湯混合弁１２２及び風呂混合弁１２５の湯側供給経路にも逆止弁１２９、１３０を設けるとともに、給湯混合弁１２２の出力側には逆止弁１３１を設けている。 A check valve 128 is provided in the intermediate temperature water supply path of the first mixing valve 120 so as to prevent the reverse flow of the intermediate temperature water from the intermediate tapping pipe 112. In addition, check valves 129 and 130 are provided in the hot water supply path of the hot water supply mixing valve 122 and the bath mixing valve 125, and a check valve 131 is provided on the output side of the hot water supply mixing valve 122.

また、カラン１２４の近傍には給湯リモコン１３２、浴室には風呂リモコン１３３が設けられている。この給湯リモコン１３２または風呂リモコン１３３からの運転指示は機器本体側に設けられた制御部１３４に無線または有線で送られ、送信された条件に従って制御部１３４で予め規定された制御動作に基づいて各種動作を行うようにしている。 A hot water remote controller 132 is provided in the vicinity of the currant 124, and a bath remote controller 133 is provided in the bathroom. The operation instruction from the hot water remote controller 132 or the bath remote controller 133 is sent wirelessly or by wire to a control unit 134 provided on the apparatus body side, and various operations are performed based on the control operations previously defined by the control unit 134 according to the transmitted conditions. I try to do it.

また、制御部１３４には２４時間を計時するカレンダー機能付きのタイマー部１４０が設けられており、このタイマー部１４０により全量沸き上げ運転を行う夜間時間帯、すなわち深夜電力時間帯（例えば、２３時〜７時）と、湯切れ沸き上げ運転を行う昼間時間帯（７時〜２３時）を設定するようにしている。 In addition, the control unit 134 is provided with a timer unit 140 with a calendar function that measures 24 hours, and the timer unit 140 performs a full-time boiling operation, that is, a midnight power period (for example, 23:00) ~ 7 o'clock) and the daytime time zone (7 o'clock to 23 o'clock) in which the hot water boiling operation is performed.

本実施の形態における貯湯式給湯装置は、図２に示すような沸き上げ回路１０２により深夜電力時間帯（例えば、２３時〜７時）に予め設定された沸き上げモードに従って貯湯タンク１０１の全量沸き上げ動作を行い、昼間時間帯（７時〜２３時）に貯湯タンク１０１の壁面に取り付けられた残湯湯温検出器１３５、１３６、１３７で検出される温度に基づいて残湯量が減少し湯量不足が発生すると思われる場合は湯切れ沸き上げ動作を行い、貯湯タンク１０１の上部に必要な高温水湯量を確保するようにしている。以上のような沸き上げ動作によって、貯湯タンク１０１には上部から高温水、中温水、低温水の順で層をなして蓄積されることになる。 The hot water storage type hot water supply apparatus in the present embodiment is configured to boil the entire amount of the hot water storage tank 101 in accordance with a heating mode preset in a midnight power time zone (for example, from 23:00 to 7:00) by a boiling circuit 102 as shown in FIG. The amount of remaining hot water decreases and the amount of hot water decreases based on the temperature detected by the remaining hot water temperature detectors 135, 136, and 137 attached to the wall surface of the hot water storage tank 101 during the daytime period (7 to 23:00). When it seems that the shortage will occur, the hot water boiling operation is performed to secure the necessary amount of hot water in the upper part of the hot water storage tank 101. By the above boiling operation, the hot water storage tank 101 accumulates in layers in the order of high temperature water, medium temperature water, and low temperature water from the top.

さらに、前記残湯湯温検出器１３５、１３６、１３７のうち、中温出湯管１１２の近傍に設けた残湯湯温検出器１３６は貯湯タンク１０１内に中温水が存在しているか否かを判断するため、予め定めた第１設定温度（例えば３０℃）と比較し、比較結果が残湯湯温検出器１３６で検出される温度が第１設定温度以上の場合は、中温出湯管１１２の近傍の貯湯タンク１０１内に中温水が存在していると判断する中部温度検出手段を構成している。 Further, of the remaining hot water temperature detectors 135, 136, and 137, the remaining hot water temperature detector 136 provided in the vicinity of the intermediate hot water discharge pipe 112 determines whether or not the intermediate hot water exists in the hot water storage tank 101. Therefore, when compared with a predetermined first set temperature (for example, 30 ° C.) and the temperature detected by the remaining hot water temperature detector 136 is equal to or higher than the first set temperature, in the vicinity of the medium temperature hot water discharge pipe 112 The middle temperature detecting means for determining that the medium temperature water is present in the hot water storage tank 101 is configured.

また、残湯湯温検出器１３７は貯湯タンク１０１の上部の高温水が使用され給水管１０５から新たな水が供給されて貯湯タンク１０１内の湯水が停滞することなく流動しているか否かを判断するため、予め定めた第２設定温度（例えば４５℃）と比較し、この比較結果において残湯湯温検出器１３７で検出される温度が第２設定温度を一度も下回っていないと判断したとき、貯湯タンク１０１内の湯水が使用されていない、または、使用量が極端に少ないと判断する上部温度検出手段を構成している。 Further, the remaining hot water temperature detector 137 determines whether or not hot water in the hot water storage tank 101 is flowing without stagnation because high temperature water in the upper part of the hot water storage tank 101 is used and new water is supplied from the water supply pipe 105. In order to judge, it compares with the predetermined 2nd preset temperature (for example, 45 degreeC), and it judged that the temperature detected with the remaining hot water temperature detector 137 was not less than the 2nd preset temperature in this comparison result. When the hot water in the hot water storage tank 101 is not used or the amount of use is extremely small, the upper temperature detecting means is configured.

このように蓄積された貯湯水は、給湯リモコン１３２または風呂リモコン１３３からの要求により制御部１３４が利用側回路の負荷側混合弁を制御して所望の湯水を利用側端末に供給するようにしている。 The stored hot water is supplied from the hot water remote controller 132 or the bath remote controller 133 so that the control unit 134 controls the load side mixing valve of the usage side circuit to supply desired hot water to the usage side terminal. Yes.

その本実施の形態における利用側回路の動作の一例を図３、図４を用いて説明すると、まず、給湯リモコン１３２により所望の給湯温度が設定されカラン１２４が開栓されると、給水管１０５から貯湯タンク１０１に給水が開始され、その給水圧により貯湯タンク１０１内の中温水は中間出湯管１１２より排出され、給水管１０５より供給される水道水とともに、第１混合弁１２０の湯側ａ及び水側ｂに供給される。このとき、第１混合弁１２０の初期設定として湯側ａを略全開状態にしておくと貯湯タンク１０１内の中温水が優先的に排出され、混合出口側ｃより次段に供給される。この湯温を第１温度検出器１２１で検出し、検出された湯温が給湯リモコン１３２で設定された温度より所定温度（例えば２℃）以下の場合は、これ以上湯側に弁開度を調節することができないため、この状態で中温水の供給を継続し、次段の給湯混合弁１２２により出湯管１１１からの高温水と混合して設定温度の湯をカラン１２４に供給する。 An example of the operation of the user side circuit in the present embodiment will be described with reference to FIGS. 3 and 4. First, when a desired hot water supply temperature is set by the hot water supply remote controller 132 and the currant 124 is opened, the water supply pipe 105 is opened. Water supply to the hot water storage tank 101 is started, and the medium temperature water in the hot water storage tank 101 is discharged from the intermediate hot water discharge pipe 112 by the supply water pressure, and together with tap water supplied from the water supply pipe 105, the hot water side a of the first mixing valve 120 And supplied to the water side b. At this time, if the hot water side a is substantially fully opened as the initial setting of the first mixing valve 120, the medium temperature water in the hot water storage tank 101 is preferentially discharged and supplied to the next stage from the mixing outlet side c. When this hot water temperature is detected by the first temperature detector 121 and the detected hot water temperature is lower than the temperature set by the hot water supply remote controller 132 by a predetermined temperature (for example, 2 ° C.), the valve opening is further increased to the hot water side. Since it cannot be adjusted, the supply of medium-temperature water is continued in this state, and hot water at a set temperature is supplied to the currant 124 by being mixed with hot water from the hot water discharge pipe 111 by the hot water supply mixing valve 122 in the next stage.

次に、第１温度検出器１２１で検出された湯温が給湯リモコン１３２で設定された温度より高い場合は、第１混合弁１２０の水側ｂの開度を開き給水管１０５からの水道水を取り入れ中温水と混合して目標温度になるように弁開度の制御を開始する（太線で示す経路で湯水が流れる）。この制御により第１混合弁１２０の出口温度は徐々に目標温度に近づき、次段の給湯混合弁１２２の水側ｄに予め設定した目標温度の湯を供給する。そして、給湯混合弁１２２で出湯管１１１からの高温水と混合して設定温度の湯をカラン１２４に供給する。 Next, when the hot water temperature detected by the first temperature detector 121 is higher than the temperature set by the hot water remote controller 132, the opening of the water side b of the first mixing valve 120 is opened and tap water from the water supply pipe 105 is opened. Then, the valve opening is controlled so as to reach the target temperature by mixing with hot water (hot water flows along the path indicated by the thick line). By this control, the outlet temperature of the first mixing valve 120 gradually approaches the target temperature, and hot water having a preset target temperature is supplied to the water side d of the hot water supply mixing valve 122 in the next stage. Then, hot water having a set temperature is supplied to the currant 124 by being mixed with high temperature water from the hot water discharge pipe 111 by the hot water supply mixing valve 122.

以上のように、通常動作においては第１混合弁１２０により貯湯タンク１０１内に溜まった中温水を優先的に利用してカラン１２４等の利用側端末に湯水供給を行うため、貯湯タンク下方には低温水を確保することができるとともに、貯湯タンク上方の高温水の使用を最小限に抑えることができ、高ＣＯＰの沸き上げ動作と湯切れ現象の抑制を図ることができ、ヒートポンプ式給湯装置の湯水利用形態としては極めて有効な手段を確保できるものである。 As described above, in the normal operation, the hot water is supplied to the use side terminal such as the currant 124 by preferentially using the medium temperature water accumulated in the hot water storage tank 101 by the first mixing valve 120. The low-temperature water can be secured, the use of the high-temperature water above the hot water tank can be minimized, the boiling operation of the high COP and the suppression of the hot water phenomenon can be achieved. A very effective means can be secured as a hot water utilization form.

しかしながら、上記構成における中温水の優先的な利用形態は、貯湯タンク１０１内に中温水が存在する状態で湯水の利用量が極端に少ない、あるいは全く使用しない状態が長時間継続すると、貯湯タンク１０１内の湯水温度が低下し、貯湯タンク１０１の下部において雑菌が繁殖しやすい温度分布になり、特に、レジオネラ菌が繁殖すると人体に危害を及ぼす場合がある。つまり、湯水の利用が極端に少なく貯湯タンク１０１内の湯水の流動がなくなるとレジオネラ菌等の雑菌が繁殖しやすい状態となり、このような状態で使用を継続していると、雑菌が繁殖した貯湯タンク下部に近い中温出湯管１１２から優先的に湯水を取り出すため、繁殖した雑菌は中温出湯管１１２から給湯利用の早い時期に流出されることになり、カラン１２４等を介して外部に排出される。排出された雑菌の中にレジオネラ菌が混入していると空気中に飛散し、呼吸器系より人体に悪影響を及ぼすことになる。 However, the preferential use form of the medium-temperature water in the above configuration is that when the amount of hot-water used is extremely small or not used at all for a long time while the medium-temperature water exists in the hot-water tank 101, the hot-water tank 101 The temperature of the hot water in the inside decreases, and the temperature distribution is such that miscellaneous bacteria are likely to propagate in the lower part of the hot water storage tank 101. In particular, when Legionella bacteria propagate, there is a possibility of causing harm to the human body. That is, if the use of hot water is extremely small and the hot water in the hot water storage tank 101 stops flowing, it becomes easy for bacteria such as Legionella bacteria to propagate, and if the use is continued in such a state, the hot water storage where the bacteria propagated. Since hot water is preferentially taken out from the intermediate temperature hot water pipe 112 close to the lower part of the tank, the propagated miscellaneous bacteria will be discharged from the intermediate temperature hot water pipe 112 at an early stage when hot water is used, and discharged to the outside through the currant 124 or the like. . If Legionella bacteria are mixed in the discharged germs, they will be scattered in the air, which will adversely affect the human body from the respiratory system.

そこで、本実施の形態における給湯装置は、全量沸き上げ運転を行う夜間時間帯に入るときに、まず、残湯湯温検出器１３６で構成する中部温度検出手段により、貯湯タンク１０１の略中間部において中温水が存在するか否かを検出する。つまり、残湯湯温検出器１３６で検出される温度が第１設定温度（例えば、３０℃）以上か否かを判断し、第１設定温度以上であると判断したときは中温水が存在すると判断し、第１設定温度以下であると判断した場合は貯湯タンク１０１内に給水管から多量の水が供給されている、いわゆるタンク内湯水の利用量が多く、停滞することなく流動していると判断する。 Therefore, when the hot water supply apparatus in the present embodiment enters the night time zone in which the full-boiling operation is performed, first, the middle temperature detection means configured by the remaining hot water temperature detector 136 is used to obtain a substantially intermediate portion of the hot water storage tank 101. It is detected whether or not medium temperature water exists. That is, it is determined whether the temperature detected by the remaining hot water temperature detector 136 is equal to or higher than a first set temperature (for example, 30 ° C.). When it is determined that the temperature is equal to or lower than the first set temperature, a large amount of water is supplied from the water supply pipe into the hot water storage tank 101, and the amount of hot water used in the tank is large and flows without stagnation. Judge.

次に、残湯湯温検出器１３７で構成する上部温度検出手段により、貯湯タンク１０１の略上部において高温水の入れ替り現象があるか否かを検出する。つまり、全量沸き上げ運転を行う夜間時間帯に入るまでに残湯湯温検出器１３７で検出される温度が予め設定した
第２設定温度（例えば、４５℃）以下になったことがあるか否かを判断し、一度でも残湯湯温検出器１３７で検出される温度が第２設定温度を下回った場合は、貯湯タンク１０１の略上部において高温水と中温水以下の低温水との入れ替り現象が発生し、タンク内湯水が使用により流動したものと判断し、一度も第２設定温度を下回らない場合は使用量が極端に少ないか、全く使用されず、タンク内湯水が停滞しているものと判断する。 Next, the upper temperature detecting means constituted by the remaining hot water temperature detector 137 detects whether or not there is a high temperature water replacement phenomenon in a substantially upper part of the hot water storage tank 101. That is, whether or not the temperature detected by the remaining hot water temperature detector 137 has become equal to or lower than a preset second set temperature (for example, 45 ° C.) before entering the night time zone in which the total amount heating operation is performed. If the temperature detected by the remaining hot water temperature detector 137 is lower than the second set temperature even once, the phenomenon of switching between the high temperature water and the low temperature water below the middle temperature water substantially in the upper part of the hot water storage tank 101. When the water temperature in the tank is judged to have flowed due to use and the temperature has never dropped below the second set temperature, the amount used is extremely small or not used at all, and the water in the tank is stagnant Judge.

以上、中部温度検出手段と上部温度検出手段により、貯湯タンク１０１内に中温水が存在し、タンク内湯水の流動が確認できないという判断がされたとき、中温出湯管１１２からの出湯を禁止する中温水使用禁止モードとし、第１混合弁１２０の水側ｂの弁開度を全開状態となるように駆動し、その後、所定の条件を満足して制御部１３４より制御禁止解除信号が出力されるまで、第１混合弁１２０の制御を禁止状態とする中温水使用禁止モードを継続し、湯側全開状態を保持するようにしている。 As described above, when it is determined by the middle temperature detection means and the upper temperature detection means that the medium temperature water exists in the hot water storage tank 101 and the flow of the hot water in the tank cannot be confirmed, the hot water discharge from the medium temperature hot water discharge pipe 112 is prohibited. The hot water use prohibition mode is set, the valve opening on the water side b of the first mixing valve 120 is driven to be fully opened, and then a control prohibition release signal is output from the control unit 134 satisfying a predetermined condition. Until then, the middle hot water use prohibition mode in which the control of the first mixing valve 120 is prohibited is continued, and the hot water side fully open state is maintained.

この制御により、中温水使用禁止モード期間中の湯水利用形態は、給水管１０５から供給される水道水を第１混合弁１２０を介して負荷側混合弁である給湯混合弁１２２の水側ｄに供給し、出湯管１１１から供給される湯側ｅの高温水と混合して設定温度の湯水をカラン１２４から利用することになる。 With this control, the hot water usage mode during the medium hot water use prohibition mode period is such that the tap water supplied from the water supply pipe 105 is passed through the first mixing valve 120 to the water side d of the hot water supply mixing valve 122 which is a load side mixing valve. The hot water at the set temperature is used from the currant 124 by being mixed with the hot water on the hot water side e supplied from the hot water outlet pipe 111.

この利用形態により、湯水の利用量が極端に少ない、または全く使用されず、タンク内湯水の流動が停滞する期間中に貯湯タンク１０１の下部にレジオネラ菌等の雑菌が繁殖したとしても、中温水使用禁止モード期間中の給湯利用において中温出湯管１１２からの湯水供給は禁止されることになり、タンク上部の比較的高温状態の湯を優先的に利用するため、雑菌の流出を抑制することができる。 Even if miscellaneous bacteria such as Legionella bacteria propagate in the lower part of the hot water storage tank 101 during the period when the flow of hot water in the tank is stagnant due to extremely little or no use of hot water, In hot water use during the use prohibition mode, hot water supply from the intermediate temperature hot water discharge pipe 112 is prohibited, and since hot water at a relatively high temperature in the upper part of the tank is used preferentially, it is possible to suppress the outflow of various bacteria. it can.

そして、中温水使用禁止モードにおいて貯湯タンク１０１の全量沸き上げ運転が行われ、貯湯タンク１０１内の全量がレジオネラ菌等の雑菌が死滅する温度、例えば６５℃以上になると、制御部１３４は第１混合弁１２０の制御禁止解除信号を出力し、通常の中温出湯管１１２からの中温水優先取り出しによる混合制御を再開させるようにしている。 Then, when the entire hot water storage tank 101 is heated in the medium hot water use prohibition mode and the total amount in the hot water storage tank 101 reaches a temperature at which miscellaneous bacteria such as Legionella bacteria are killed, for example, 65 ° C. or higher, the control unit 134 A control prohibition release signal for the mixing valve 120 is output, and the mixing control by normal temperature hot water preferential removal from the medium temperature hot water discharge pipe 112 is resumed.

その具体的実施形態として、中部温度検出手段と上部温度検出手段により中温水使用禁止モードであると判断されたとき、最初の夜間時間帯に実施される全量沸き上げ運転が経過した後の湯切れ沸き上げ運転を行う昼間時間帯になってから、第１混合弁１２０の制御禁止を解除し、中温水使用禁止モードから通常モードに変更するようにしたもので、中温水使用禁止モード中は第１混合弁１２０の制御を禁止して中温出湯管１１２からの湯水の供給を禁止するため、中温水使用禁止モード中に貯湯タンク１０１下部に繁殖したレジオネラ菌等の雑菌の流出を防止することができ、夜間時間帯を経過することで貯湯タンク１０１下部の湯水を含むタンク全量をレジオネラ菌が死滅する６５℃以上の湯温に沸き上げることができ、この全量沸き上げ運転の時間帯を経過した後に第１混合弁１２０の制御を用いて湯水混合制御を行うことで、レジオネラ菌等の雑菌が存在しない状態で効果的な湯水利用形態を確保することができる。 As a specific embodiment thereof, when the middle temperature detection means and the upper temperature detection means determine that the medium warm water use prohibition mode is set, the hot water runs out after the full-boiling operation performed in the first night time period has elapsed. After the daytime period when the boiling operation is performed, the control prohibition of the first mixing valve 120 is canceled, and the medium warm water use prohibition mode is changed to the normal mode. Since the control of the 1 mixing valve 120 is prohibited and the supply of hot water from the intermediate temperature hot water discharge pipe 112 is prohibited, it is possible to prevent the outflow of various bacteria such as Legionella bacteria that have propagated in the lower part of the hot water storage tank 101 during the intermediate temperature water use prohibition mode. It is possible to boil the entire tank containing hot water at the bottom of the hot water storage tank 101 to a hot water temperature of 65 ° C. or higher at which Legionella dies. By performing the hot and cold water mixing control using the control of the first mixing valve 120 after a lapse of time zone operation, it is possible to ensure effective hot water utilization form in the absence of bacteria, such as Legionella.

なお、中温水の有無及び使用状況の有無を判断するため設定した第１設定温度及び第２設定温度の値は本実施の形態に限定されるものではなく、タンク容量等に応じて任意に設定することが可能である。 Note that the values of the first set temperature and the second set temperature set to determine the presence / absence of the medium temperature water and the use status are not limited to the present embodiment, and are arbitrarily set according to the tank capacity and the like. Is possible.

上記実施の形態における具体的な制御動作を図５のフローチャートを用いて説明すると、まず、図５において、ステップ１で中温出湯管１１２からの中温水の優先的な利用による通常動作が行われており、ステップ２で夜間時間帯に入ったか否かを判断し、夜間時間帯に入ったと判断したときは、ステップ３で残湯湯温検出器１３６で検出される湯温が予め設定した第１設定温度以上か否かを判断し、第１設定温度以上の場合は貯湯タンク１０
１内に中温水が存在すると判断する。そして、第１設定温度以下の場合は給水管１０５から給水があり、タンク内湯水の流動があると判断して、ステップ６に進んで全量沸き上げ運転を開始する。ステップ３で中温水が存在すると判断したときはステップ４で残湯湯温検出器１３７で検出される湯温が全量沸き上げ運転を行う夜間時間帯に入るまでに予め設定した第２設定温度を下回ったことがあるか否かを判断し、一度でも下回ったことがあると判断したときは、タンク内湯水の流動があると判断して、ステップ６に進んで全量沸き上げ運転を開始する。ステップ４で一度も下回ったことがないと判断したときは、中温水使用禁止モードとし、第１混合弁１２０の弁開度を水側ｂが全開状態となるよう駆動し、その後第１混合弁１２０の弁開度の制御を禁止状態とする。次に、ステップ６で貯湯タンク１０１の全量沸き上げ運転が完了したか否かを判断し、完了したと判断したとき、つまり、貯湯タンク１０１内の湯温が雑菌等が死滅する所定温度以上になったとき、ステップ７で第１混合弁１２０の制御禁止状態を解除し、通常動作に復帰させるようにしている。 The specific control operation in the above embodiment will be described with reference to the flowchart of FIG. 5. First, in FIG. 5, a normal operation is performed by preferential use of the intermediate temperature water from the intermediate temperature hot water pipe 112 in Step 1. In step 2, it is determined whether or not the night time zone has been entered. If it is determined that the night time zone has been entered, the remaining hot water temperature detector 136 detects in step 3 the first hot water temperature detected in advance. It is determined whether or not the temperature is higher than the preset temperature.
It is determined that there is medium temperature water in 1. When the temperature is equal to or lower than the first set temperature, it is determined that water is supplied from the water supply pipe 105 and there is a flow of hot water in the tank, and the process proceeds to step 6 to start a full-boiling operation. When it is determined in step 3 that medium-temperature water exists, the second set temperature set in advance until the hot water temperature detected by the remaining hot water temperature detector 137 in step 4 enters the night time zone during which the entire boiling water operation is performed. It is determined whether or not it has fallen below, and when it is determined that it has fallen even once, it is determined that there is a flow of hot water in the tank, and the routine proceeds to step 6 to start a full-boiling operation. When it is determined in step 4 that it has never fallen below, the mode is set to the medium hot water use prohibition mode, the valve opening of the first mixing valve 120 is driven so that the water side b is fully opened, and then the first mixing valve The control of the valve opening of 120 is prohibited. Next, it is determined in step 6 whether or not the entire boiling water heating operation of the hot water storage tank 101 has been completed, and when it is determined that it has been completed, that is, the hot water temperature in the hot water storage tank 101 is equal to or higher than a predetermined temperature at which germs and the like are killed. When this happens, the control prohibition state of the first mixing valve 120 is canceled in step 7 to return to the normal operation.

なお、ステップ６の全量沸き上げ運転完了の判断として、昼間時間帯になったか否かを判断して、昼間時間帯になってから第１混合弁１２０の制御禁止状態を解除するようにすることで回路構成の簡素化が図れるものである。 In addition, as a judgment of the completion of all-boiling operation in step 6, it is judged whether or not it is the daytime time zone, and the control prohibition state of the first mixing valve 120 is released after the daytime time zone is reached. Thus, the circuit configuration can be simplified.

以上のように、本発明貯湯式給湯装置は、ヒートポンプ式給湯装置の湯水利用形態として極めて有効な手段である中温水を優先的に使用可能な湯水混合制御方法を提供しつつ、使用湯量が極端に少なく湯水の利用が停滞したときの安全性を確保したものであり、熱源に関係なく湯水混合制御全般に適用できるものである。 As described above, the hot water storage type hot water supply apparatus of the present invention provides a hot water mixing control method capable of preferentially using medium hot water, which is an extremely effective means for using hot water in a heat pump type hot water supply apparatus, while the amount of hot water used is extremely high. Therefore, it is possible to ensure the safety when the use of hot water is stagnant, and can be applied to general hot water mixing control regardless of the heat source.

本発明の実施の形態１における貯湯式給湯装置の構成図The block diagram of the hot water storage type hot water supply apparatus in Embodiment 1 of this invention 同貯湯式給湯装置における沸き上げ動作を示す図The figure which shows the boiling operation in the hot water storage type hot water supply apparatus 同貯湯式給湯装置における湯水利用形態の一例を示す図The figure which shows an example of the hot water usage form in the hot water storage type hot water supply apparatus 同貯湯式給湯装置における湯水利用形態の別の一例を示す図The figure which shows another example of the hot water usage form in the hot water storage type hot water supply apparatus 同貯湯式給湯装置における制御動作を示すフローチャートFlow chart showing control operation in the hot water storage type hot water supply apparatus

符号の説明Explanation of symbols

１０１貯湯タンク
１０５給水管
１０６ヒートポンプ回路
１１１出湯管
１１２中温出湯管
１２０第１混合弁
１２２給湯混合弁（負荷側混合弁）
１２５風呂混合弁（負荷側混合弁）
１３４制御部
１３５残湯湯温検出器（中部温度検出手段）
１３７残湯湯温検出器（上部温度検出手段）
１４０タイマー部 DESCRIPTION OF SYMBOLS 101 Hot water storage tank 105 Water supply pipe 106 Heat pump circuit 111 Hot water discharge pipe 112 Medium temperature hot water supply pipe 120 1st mixing valve 122 Hot water supply mixing valve (load side mixing valve)
125 Bath mixing valve (load-side mixing valve)
134 control unit 135 remaining hot water temperature detector (central temperature detection means)
137 Residual hot water temperature detector (upper temperature detection means)
140 Timer part

Claims

ヒートポンプ回路を用いて加熱した湯水をタンク上部から成層状態で貯湯しその湯水を利用して端末側に所望の湯水を供給する貯湯式給湯装置において、
タンク上部の湯水を取り出す出湯管と、タンクの略中間部の湯水を取り出す中温出湯管と、タンク下部に水道水を供給する給水管と、前記中温出湯管近傍のタンク内湯温を検出する中部温度検出手段と、前記中温出湯管と上部出湯管の間のタンク内湯温を検出する上部温度検出手段と、前記給水管と前記中温出湯管からの湯水を混合する第１混合弁と、前記第１混合弁からの湯水と前記出湯管からの高温水を混合し所定温度の湯水を端末側に供給する利用側混合弁と、前記第１混合弁と利用側混合弁の弁開度制御を行う制御部とを備え、
全量沸き上げ運転を行う時間帯を設定するとともに、湯量不足を判断したとき湯切れ沸き上げ運転を行うことを設定した貯湯式給湯装置であって、
前記制御部は、全量沸き上げ運転を行う時間帯に前記中部温度検出手段で検出される湯温が中温水の有無を判断する第１設定温度以上あり、かつ、前記上部温度検出手段で検出される湯温が使用状況を判断する第２設定温度を一度も下回っていないとき中温水使用禁止モードと判断し、前記第１混合弁の制御を禁止するようにした貯湯式給湯装置。 In a hot water storage hot water supply apparatus that stores hot water heated using a heat pump circuit in a stratified state from the upper part of the tank and supplies the desired hot water to the terminal side using the hot water,
A tapping pipe that takes out hot water at the top of the tank, a medium temperature tapping pipe that takes out hot water at the middle of the tank, a water supply pipe that supplies tap water to the bottom of the tank, and a middle temperature that detects the temperature of the hot water in the tank near the middle temperature tapping pipe Detecting means; upper temperature detecting means for detecting hot water in the tank between the intermediate hot water outlet pipe and the upper hot water outlet pipe; a first mixing valve for mixing hot water from the water supply pipe and the intermediate hot water hot pipe; A control valve that controls hot water from the mixing valve and hot water from the outlet pipe and supplies hot water at a predetermined temperature to the terminal side, and performs valve opening control of the first mixing valve and the usage side mixing valve. With
A hot water storage type hot water supply apparatus that sets a time zone for performing a full-boiling operation and sets a hot-water boiling operation when it is determined that the amount of hot water is insufficient,
The control unit has a hot water temperature detected by the middle temperature detection means in a time zone during which the whole amount heating operation is performed is equal to or higher than a first set temperature for determining the presence or absence of middle temperature water, and is detected by the upper temperature detection means. A hot water storage type hot water supply apparatus in which the medium hot water use prohibition mode is determined and the control of the first mixing valve is prohibited when the hot water temperature has never fallen below the second set temperature for determining the use state.

制御部は、中温水使用禁止モードになったとき、第１混合弁を水側全開状態とし、中温出湯管からの湯水供給を禁止するようにした請求項１記載の貯湯式給湯装置。 The hot water storage type hot water supply apparatus according to claim 1, wherein the control unit sets the first mixing valve to a water side full open state and prohibits the hot water supply from the intermediate temperature hot water pipe when the medium warm water use prohibition mode is set.

制御部は、中温水使用禁止モードになったとき、予め定めた沸き上げ条件で全量沸き上げ運転の完了が確認されたとき、第１混合弁の制御禁止を解除するようにした請求項１または２記載の貯湯式給湯装置。 The control unit is configured to release the control prohibition of the first mixing valve when the completion of the full-boiling operation is confirmed under a predetermined boiling condition when the medium warm water use prohibition mode is set. The hot water storage type hot water supply apparatus according to 2.

制御部は、中温水使用禁止モードになったとき、最初の全量沸き上げ運転の時間帯が経過した後の湯切れ沸き上げ運転を行う時間帯になってから、第１混合弁の制御禁止を解除するようにした請求項１または２記載の貯湯式給湯装置。 When the control unit enters the mode for prohibiting the use of medium-temperature water, the control of the first mixing valve is prohibited after the time period for performing the hot water boiling operation after the time for the first full-boiling operation has elapsed. The hot water storage type hot water supply apparatus according to claim 1 or 2, wherein the hot water storage type hot water supply apparatus is released.