JP2009085476A

JP2009085476A - Heat pump water heater

Info

Publication number: JP2009085476A
Application number: JP2007254033A
Authority: JP
Inventors: Akira Fujitaka; 章藤高; Kazuo Nakatani; 和生中谷; Noriho Okaza; 典穂岡座; Yasuhiko Isayama; 安彦諌山; Yoshiki Yamaoka; 由樹山岡
Original assignee: Panasonic Corp
Current assignee: Panasonic Corp
Priority date: 2007-09-28
Filing date: 2007-09-28
Publication date: 2009-04-23

Abstract

<P>PROBLEM TO BE SOLVED: To perform a heat pump hot water supply operation of high energy efficiency by preventing a rise of a water temperature at a lower portion of a hot water storage tank. <P>SOLUTION: This heat pump water heater comprises a refrigerant circuit constituted by successively connecting a heat exchanger 32 for hot water supply, a pressure reducing means 33 and an evaporator 34, a hot water supply circuit for circulating the water from the lower portion of the hot water storage tank 31 to an upper portion of the hot water storage tank 41 while passing through the heat exchanger 32 for hot water supply and a three-way valve 44 through a circulation pump 43, and a bypass circuit 47 connecting the three-way valve 44 and the lower portion of the hot water storage tank 41, and the three-way valve 44 is controlled to make the heat exchanger 32 for hot water supply communicate with the lower portion of the hot water storage tank 41 at the stop of the circulation pump 43 or a low flow-rate operation by the circulation pump 43, and thus the back-flow of the hot water of high-temperature at the upper portion of the hot water storage tank 41 and the rise of the water temperature at the lower portion of the hot water storage tank 41 are prevented, and the hot water supply operation of high energy efficiency can be performed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は貯湯式のヒートポンプ給湯装置に関する。 The present invention relates to a hot water storage type heat pump hot water supply apparatus.

従来、この種のヒートポンプ給湯装置は、図２に示すものがある（例えば、特許文献１参照）。図２において、ヒートポンプ給湯装置は、圧縮機１、給湯用熱交換器２、減圧手段３、蒸発器４からなる冷媒循環回路と、貯湯槽５、循環ポンプ６、前記給湯用熱交換器２、三方弁７、貯湯槽５頂部の温水戻り口８を順次接続した給湯回路と、前記三方弁７と前記貯湯槽５底部を接続するバイパス回路からなる。 Conventionally, this type of heat pump hot-water supply apparatus has what is shown in FIG. 2 (for example, refer patent document 1). In FIG. 2, the heat pump hot water supply apparatus includes a refrigerant circulation circuit including a compressor 1, a hot water supply heat exchanger 2, a decompression means 3, and an evaporator 4, a hot water storage tank 5, a circulation pump 6, the hot water supply heat exchanger 2, It consists of a hot water supply circuit in which the three-way valve 7 and the hot water return port 8 at the top of the hot water tank 5 are sequentially connected, and a bypass circuit that connects the three-way valve 7 and the bottom of the hot water tank 5.

運転を開始すると、循環ポンプ６が運転され、貯湯槽５から給湯用熱交換器２に流入する入水温度が計測され、室外気温、入水温度と出湯目標温度により、圧縮機１の運転周波数、減圧手段３の初期開度が決定され、圧縮機１が運転開始する。圧縮機１より吐出された冷媒は次第に高温高圧の過熱ガス冷媒となり、給湯用熱交換器２に流入し、ここで循環ポンプ６から送られてきた給湯水を加熱する。 When the operation is started, the circulation pump 6 is operated, the temperature of the incoming water flowing into the hot water supply heat exchanger 2 from the hot water storage tank 5 is measured, and the operating frequency and pressure of the compressor 1 are reduced by the outdoor air temperature, the incoming water temperature and the target hot water temperature. The initial opening degree of the means 3 is determined, and the compressor 1 starts operation. The refrigerant discharged from the compressor 1 gradually becomes a high-temperature and high-pressure superheated gas refrigerant and flows into the hot water supply heat exchanger 2 where the hot water supplied from the circulation pump 6 is heated.

そして、凝縮液化した冷媒は減圧手段３で減圧され、蒸発器４に流入し、ここで大気熱を吸熱して蒸発ガス化し、圧縮機１にもどる。一方、給湯用熱交換器２で加熱された湯はその温度が給湯設定温度（例えば８０℃）より一定値低い温度（例えば７０℃）より低い場合、貯湯槽５の低部に戻り、給湯設定温度（例えば８０℃）より一定値低い温度（例えば７０℃）より高くなると三方弁７を切り替え、貯湯槽５の上部に流入し、貯湯槽５の上から次第に貯湯されていく。 The condensed and liquefied refrigerant is decompressed by the decompression means 3 and flows into the evaporator 4, where it absorbs atmospheric heat to evaporate and returns to the compressor 1. On the other hand, when the temperature of the hot water heated by the heat exchanger 2 for hot water supply is lower than a temperature (for example, 70 ° C.) lower than a set temperature of the hot water supply (for example, 80 ° C.), the hot water returns to the lower part of the hot water tank 5 When the temperature becomes higher than a temperature (for example, 70 ° C.) lower than a temperature (for example, 80 ° C.), the three-way valve 7 is switched, flows into the upper part of the hot water tank 5, and is gradually stored from above the hot water tank 5.

そして、給湯用熱交換器２の入口水温が設定値に達すると入水温度センサー２０が検知し、圧縮機１によるヒートポンプ運転を停止するものである。さらに、室外気温が低く蒸発器４に霜が生成し、その霜を溶かす除霜運転を行う場合、循環ポンプ６を停止し、給湯運転を停止し、減圧手段３を開き、高温高圧の冷媒を蒸発器４に流し、その熱により除霜する。除霜運転終了後、給湯運転を再開するが、給湯用熱交換器２の出口温度が給湯設定温度（例えば８０℃）より一定値低い温度（例えば７０℃）より低い場合、貯湯槽５の低部に戻るように三方弁７は制御され、給湯用熱交換器２の出口温度が給湯設定温度（例えば８０℃）より一定値低い温度（例えば７０℃）より高くなると三方弁７を切り替え、貯湯槽５の上部に流入し貯湯されていく。
特開昭６０−１６５１５７号公報 Then, when the inlet water temperature of the hot water supply heat exchanger 2 reaches a set value, the incoming water temperature sensor 20 detects it, and the heat pump operation by the compressor 1 is stopped. Furthermore, when the outdoor temperature is low and frost is generated in the evaporator 4 and the defrosting operation is performed to melt the frost, the circulation pump 6 is stopped, the hot water supply operation is stopped, the decompression means 3 is opened, and the high-temperature and high-pressure refrigerant is supplied. It flows into the evaporator 4 and defrosts with the heat. After completion of the defrosting operation, the hot water supply operation is resumed. However, when the outlet temperature of the hot water supply heat exchanger 2 is lower than a temperature (for example, 70 ° C.) lower than a set temperature of the hot water supply (for example, 80 ° C.) by a low value, The three-way valve 7 is controlled so as to return to the section, and the three-way valve 7 is switched when the outlet temperature of the hot water supply heat exchanger 2 becomes higher than a set temperature (for example, 70 ° C.) lower than a set temperature (for example, 80 ° C.) It flows into the upper part of the tank 5 and is stored.
JP 60-165157 A

しかしながら、上記のような従来の構成では、循環ポンプを停止したり、または循環ポンプを低流量で運転する場合、三方弁７を貯湯槽５の上部に流入するようにしておくと、貯湯槽５給湯用熱交換器と貯湯槽の高さの違いや水温の違いによる水の比重の違いにより、貯湯槽５上部から高温の湯が給湯熱交換器を通り貯湯槽の底部に逆流する場合があり、貯湯槽の高温の湯量が低下すると共に、貯湯槽下部の低温（例えば１０℃）の水と混合し、貯湯槽５底部の水温は上昇する。その結果、給湯運転時に給湯熱交換器２に流入する水温が上昇するため、給湯熱交換器２の放熱量が低下し、給湯機のエネルギー効率が低下するという課題がある。 However, in the conventional configuration as described above, when the circulation pump is stopped or the circulation pump is operated at a low flow rate, if the three-way valve 7 flows into the upper part of the hot water tank 5, the hot water tank 5 Due to differences in the specific gravity of water due to the difference in the height of the heat exchanger for hot water supply and the hot water tank or the difference in water temperature, hot water may flow backward from the top of the hot water tank 5 to the bottom of the hot water tank through the hot water heat exchanger. As the amount of hot water in the hot water tank decreases, it mixes with low temperature (eg, 10 ° C.) water at the bottom of the hot water tank, and the water temperature at the bottom of the hot water tank 5 rises. As a result, since the temperature of the water flowing into the hot water supply heat exchanger 2 during the hot water supply operation increases, there is a problem that the heat dissipation amount of the hot water supply heat exchanger 2 decreases and the energy efficiency of the hot water supply apparatus decreases.

本発明は前記従来の課題を解決するものであり、循環ポンプを停止したり、または循環ポンプを低流量で運転する場合、三方弁を貯湯槽下部に連通させるように制御し、貯湯槽
上部の高温の湯の逆流を防止し、エネルギー効率の高い給湯運転を可能とすることである。 The present invention solves the above-described conventional problems. When the circulation pump is stopped or the circulation pump is operated at a low flow rate, the three-way valve is controlled to communicate with the lower part of the hot water tank, and the upper part of the hot water tank is This is to prevent back flow of hot water and enable hot water supply operation with high energy efficiency.

前記従来の課題を解決するために、本発明のヒートポンプ給湯装置は、圧縮機、給湯用熱交換器、減圧手段、蒸発器を順次接続した冷媒回路と、貯湯槽の下部から循環ポンプを介して、前記給湯用熱交換器、三方弁を通過し、前記貯湯槽の上部へと水を循環させる給湯回路と、前記三方弁と前記貯湯槽の下部と接続するバイパス回路とを備え、前記循環ポンプの停止時または前記循環ポンプによる低流量運転時、前記給湯用熱交換器と前記貯湯槽の下部とが連通するように、前記三方弁を制御することを特徴するもので、貯湯槽上部の高温の湯の逆流と、貯湯槽下部の水温上昇を防止し、エネルギー効率の高い給湯運転を行うことができる。 In order to solve the conventional problems, a heat pump hot water supply apparatus of the present invention includes a refrigerant circuit in which a compressor, a heat exchanger for hot water supply, a decompression unit, and an evaporator are sequentially connected, and a circulation pump from the lower part of the hot water tank. A hot water supply circuit that passes through the three-way valve and circulates water to the upper part of the hot water tank, and a bypass circuit that connects the three-way valve and the lower part of the hot water tank. The three-way valve is controlled so that the hot water supply heat exchanger and the lower part of the hot water tank communicate with each other at the time of stopping at a low flow rate or by the circulation pump. It is possible to prevent the reverse flow of hot water and the water temperature rise at the bottom of the hot water tank, and to perform an energy efficient hot water supply operation.

本発明のヒートポンプ給湯装置は、貯湯槽下部の水温上昇を防止し、エネルギー効率の高い給湯運転を行うことができる。 The heat pump hot water supply apparatus of the present invention can prevent an increase in the water temperature in the lower part of the hot water tank, and can perform hot water supply operation with high energy efficiency.

第１の発明は、圧縮機、給湯用熱交換器、減圧手段、蒸発器を順次接続した冷媒回路と、貯湯槽の下部から循環ポンプを介して、前記給湯用熱交換器、三方弁を通過し、前記貯湯槽の上部へと水を循環させる給湯回路と、前記三方弁と前記貯湯槽の下部と接続するバイパス回路とを備え、前記循環ポンプの停止時または前記循環ポンプによる低流量運転時、前記給湯用熱交換器と前記貯湯槽の下部とが連通するように、前記三方弁を制御することを特徴するもので、貯湯槽上部の高温の湯の逆流と、貯湯槽下部の水温上昇を防止し、エネルギー効率の高い給湯運転を行うことができる。 1st invention passes the said heat exchanger for hot water supply and a three-way valve via the circulation pump from the lower part of a hot water tank through the refrigerant circuit which connected the compressor, the heat exchanger for hot water supply, the pressure reduction means, and the evaporator one by one A hot water supply circuit that circulates water to the upper part of the hot water tank, and a bypass circuit that connects the three-way valve and the lower part of the hot water tank, when the circulating pump is stopped or when the circulating pump is operated at a low flow rate The three-way valve is controlled so that the heat exchanger for hot water supply and the lower part of the hot water tank communicate with each other, the backflow of hot water at the upper part of the hot water tank and the rise in the water temperature at the lower part of the hot water tank This makes it possible to perform hot water supply operation with high energy efficiency.

第２の発明は、給湯用熱交換器を流出する給湯水の温度を検知する出湯温度センサーを有し、前記出湯温度センサーの検知温度が目標値より低い場合には、前記給湯用熱交換器と前記貯湯槽の下部とが連通するように、三方弁を制御することを特徴とするもので、貯湯槽上部の高温の湯の逆流と、貯湯槽下部の水温上昇を防止し、エネルギー効率の高い給湯運転を行うことができる。 2nd invention has the tapping temperature sensor which detects the temperature of the hot water flowing out of the heat exchanger for hot water supply, and when the temperature detected by the tapping temperature sensor is lower than the target value, the heat exchanger for hot water supply The three-way valve is controlled so that the hot water tank and the lower part of the hot water tank communicate with each other, preventing the backflow of hot water at the upper part of the hot water tank and the rising of the water temperature at the lower part of the hot water tank. High hot water supply operation can be performed.

第３の発明は、給湯用熱交換器を流出する給湯水の温度を検知する出湯温度センサーを有し、前記出湯温度センサーの検知温度が目標値以上の場合には、前記給湯用熱交換器と前記貯湯槽の上部とが連通するように、三方弁を制御することを特徴とするもので、貯湯槽下部の水温上昇を防止し、よりエネルギー効率の高い給湯運転を行うことができる。 3rd invention has a tapping temperature sensor which detects the temperature of the hot water flowing out of the heat exchanger for hot water supply, and when the temperature detected by the tapping temperature sensor is equal to or higher than a target value, the heat exchanger for hot water supply The three-way valve is controlled so that the hot water storage tank communicates with the upper part of the hot water storage tank, so that an increase in the water temperature at the lower part of the hot water storage tank can be prevented and hot water supply operation with higher energy efficiency can be performed.

第４の発明は、給湯運転終了時は、給湯用熱交換器と貯湯槽の下部とが連通するように、三方弁を制御することを特徴とするもので、貯湯槽上部の高温の湯の逆流と、貯湯槽下部の水温上昇を防止し、エネルギー効率の高い給湯運転を行うことができる。 The fourth invention is characterized by controlling the three-way valve so that the hot water heat exchanger and the lower part of the hot water storage tank communicate with each other at the end of the hot water supply operation. It is possible to prevent the reverse flow and the water temperature rise at the bottom of the hot water tank, and to perform a hot water supply operation with high energy efficiency.

第５の発明は、除霜運転中は、給湯用熱交換器と貯湯槽の下部とが連通するように、三方弁を制御することを特徴するもので、三方弁と貯湯槽下部を接続するバイパス回路に連通させることにより、貯湯槽上部の高温の湯の逆流と、貯湯槽下部の水温上昇を防止し、エネルギー効率の高い給湯運転を行うことができる。 The fifth invention is characterized by controlling the three-way valve so that the hot water heat exchanger and the lower part of the hot water tank communicate with each other during the defrosting operation, and connects the three-way valve and the lower part of the hot water tank. By communicating with the bypass circuit, it is possible to prevent a back flow of hot water at the upper part of the hot water tank and an increase in the water temperature at the lower part of the hot water tank, and to perform a hot water supply operation with high energy efficiency.

第６の発明は、除霜運転終了後は、給湯用熱交換器と貯湯槽の上部とが連通するように、三方弁を制御することを特徴とするもので、貯湯槽下部の水温上昇を防止し、エネルギー効率の高い給湯運転を行うことができる。 The sixth invention is characterized in that after the defrosting operation is finished, the three-way valve is controlled so that the heat exchanger for hot water supply and the upper part of the hot water tank communicate with each other. This can prevent hot water operation with high energy efficiency.

第７の発明は、冷媒として炭酸ガスを用いたことを特徴とするもので、給湯水の高温化を高効率で実現すると共に、冷媒が外部に漏れた場合にも、地球温暖化への影響は非常に少なくなる。 The seventh invention is characterized in that carbon dioxide gas is used as a refrigerant, which realizes high temperature of hot water supply with high efficiency and also has an effect on global warming even when the refrigerant leaks to the outside. Are very few.

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ヒートポンプ給湯装置の構成図を示すものである。 (Embodiment 1)
FIG. 1 shows a configuration diagram of a heat pump water heater in the first embodiment of the present invention.

図１において、圧縮機３１、給湯用熱交換器３２、減圧手段３３、蒸発器３４を順に環状に接続し、冷媒として炭酸ガスを封入して冷媒循環回路を形成し、蒸発器３４は、外気を送風するためのファン３５を備えている。また、貯湯槽４１、貯湯槽下部の取水口４２、循環ポンプ４３、給湯用熱交換器３２、三方弁４４、貯湯槽上部の温水戻り口４５を順次接続した給湯回路４６と、三方弁４４と貯湯槽４１底部を接続するバイパス回路４７を構成しており、圧縮機３１より吐出された高温高圧の過熱ガス冷媒は給湯用熱交換器３２に流入し、ここで循環ポンプ４３から送られてきた水を加熱するようになっている。 In FIG. 1, a compressor 31, a hot water supply heat exchanger 32, a decompression means 33, and an evaporator 34 are connected in an annular shape in this order, and carbon dioxide gas is sealed as a refrigerant to form a refrigerant circulation circuit. A fan 35 is provided for blowing air. Further, a hot water supply circuit 46 in which a hot water storage tank 41, a water intake port 42 at the lower part of the hot water storage tank, a circulation pump 43, a heat exchanger 32 for hot water supply, a three-way valve 44, and a hot water return port 45 at the upper part of the hot water tank are sequentially connected, A bypass circuit 47 connecting the bottom of the hot water storage tank 41 is configured, and the high-temperature and high-pressure superheated gas refrigerant discharged from the compressor 31 flows into the hot water supply heat exchanger 32 where it is sent from the circulation pump 43. The water is heated.

また、給湯用熱交換器３２に流入する入水温度を検知する入水温度センサー５１と給湯用熱交換器３２から流出する出湯温度を検知する出湯温度センサー５２と室外気温を検知する室外気温センサー５３、圧縮機３１の吐出冷媒温度を検出する吐出温度センサー５４、蒸発器３４の出口冷媒温度を検出する蒸発器出口温度センサー５５を設け、圧縮機３１の運転周波数や減圧手段３３の開度、ファン３５の回転数、循環ポンプ４３の回転数を制御する制御装置５６を設置している。冷媒は二酸化炭素を用いている。 Also, an incoming water temperature sensor 51 for detecting the incoming water temperature flowing into the hot water supply heat exchanger 32, a hot water temperature sensor 52 for detecting the hot water temperature flowing out from the hot water heat exchanger 32, and an outdoor air temperature sensor 53 for detecting the outdoor air temperature, A discharge temperature sensor 54 for detecting the discharge refrigerant temperature of the compressor 31 and an evaporator outlet temperature sensor 55 for detecting the outlet refrigerant temperature of the evaporator 34 are provided. The operating frequency of the compressor 31, the opening degree of the decompression means 33, and the fan 35 are provided. And a control device 56 for controlling the rotation speed of the circulation pump 43 is installed. Carbon dioxide is used as the refrigerant.

以上のように構成されたヒートポンプ給湯装置について、以下その動作、作用を説明する。 About the heat pump hot-water supply apparatus comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

通常の運転時では、ヒートポンプ給湯装置の運転を開始すると、循環ポンプ４３、ファン３５が運転され、入水温度センサー５１により貯湯槽４１から給湯用熱交換器３２に流入する入水温度が計測され、室外気温センサー５３により室外気温が計測され、吐出温度センサー５４により圧縮機３１の吐出冷媒温度が計測され、入水温度、室外気温、吐出冷媒温度と出湯目標温度により、圧縮機３１の運転周波数、減圧手段３３の初期開度Ｐ１はあらかじめ設定されたテーブルから選択し、決定され、圧縮機３１の運転が開始される。 In normal operation, when the operation of the heat pump hot water supply device is started, the circulation pump 43 and the fan 35 are operated, and the incoming water temperature sensor 51 measures the incoming water temperature flowing into the hot water supply heat exchanger 32 from the hot water storage tank 41, and the outdoor The outdoor air temperature is measured by the air temperature sensor 53, the discharge refrigerant temperature of the compressor 31 is measured by the discharge temperature sensor 54, and the operating frequency of the compressor 31 and the pressure reducing means are determined by the incoming water temperature, the outdoor air temperature, the discharge refrigerant temperature, and the hot water target temperature. The initial opening P1 of 33 is selected and determined from a preset table, and the operation of the compressor 31 is started.

圧縮機３１より吐出された冷媒は、圧縮機３１運転開始時は低温低圧の冷媒であるが、圧縮機３１の回転数の増加に伴い、次第に高温高圧の過熱ガス冷媒となる。そして、高温高圧となった冷媒は給湯用熱交換器３２に流入し、ここで循環ポンプ４３から送られてきた水と熱交換し加熱する。 The refrigerant discharged from the compressor 31 is a low-temperature and low-pressure refrigerant at the start of operation of the compressor 31, but gradually becomes a high-temperature and high-pressure superheated gas refrigerant as the number of rotations of the compressor 31 increases. The high-temperature and high-pressure refrigerant flows into the hot water supply heat exchanger 32 where it exchanges heat with the water sent from the circulation pump 43 and heats it.

そして、冷媒は中温高圧となり、減圧手段３３で減圧された後、蒸発器３４に流入し、ここでファン３５で送風された外気と熱交換して蒸発ガス化し、圧縮機３１にもどる。一方、循環ポンプ４３で送られた給湯水は給湯用熱交換器３２で加熱され、湯温度が給湯設定温度（例えば８０℃）より第一の所定値（例えば１０ｄｅｇ）ほど低い温度（７０℃）より低い（例えば６５℃）場合、三方弁４４は給湯用熱交換器３２と貯湯槽４１底部を連通させるように制御し、温水は貯湯槽４１の底部に戻される。 Then, the refrigerant becomes a medium temperature and high pressure, and after being depressurized by the depressurizing means 33, flows into the evaporator 34, where it exchanges heat with the outside air blown by the fan 35 to be evaporated and returns to the compressor 31. On the other hand, the hot water supplied by the circulation pump 43 is heated by the hot water heat exchanger 32, and the hot water temperature is lower by a first predetermined value (for example, 10 deg) than the preset hot water temperature (for example, 80 ° C) (70 ° C). When the temperature is lower (for example, 65 ° C.), the three-way valve 44 controls the hot water supply heat exchanger 32 and the bottom of the hot water storage tank 41 to communicate with each other, and the hot water is returned to the bottom of the hot water storage tank 41.

さらに、湯温度が給湯設定温度（例えば８０℃）より第一の所定値（例えば１０ｄｅｇ）ほど低い温度（７０℃）より高くなると、三方弁４４は給湯用熱交換器３２と貯湯槽上
部の温水戻り口４５を連通させるように制御され、湯は貯湯槽４１の上部に流入し、上から次第に貯湯されて行き、沸き上げ運転時間の経過とともに貯湯槽４１内に湯が貯まって行く。沸き上げ運転完了近くになると、貯湯槽４１底部より循環ポンプ４３を経て流入する水温は高くなり、入水温度が設定値以上になると、貯湯槽４１に湯が貯まったと判断し、圧縮機３１、循環ポンプ４３、ファン３５の運転を停止し、沸上を完了する。この時、三方弁４４は給湯用熱交換器３２と貯湯槽４１底部を連通させるように制御する。 Further, when the hot water temperature becomes higher than the temperature (70 ° C.) lower than the hot water set temperature (for example, 80 ° C.) by a first predetermined value (for example, 10 deg), the three-way valve 44 causes the hot water in the hot water supply heat exchanger 32 and the hot water in the upper part of the hot water storage tank. The hot water flows into the upper part of the hot water storage tank 41 and is gradually stored from above, and hot water accumulates in the hot water storage tank 41 as the boiling operation time elapses. When the boiling operation is almost completed, the temperature of water flowing in from the bottom of the hot water tank 41 via the circulation pump 43 becomes higher, and when the incoming water temperature exceeds the set value, it is determined that hot water has accumulated in the hot water tank 41, and the compressor 31, circulation The operation of the pump 43 and the fan 35 is stopped, and boiling is completed. At this time, the three-way valve 44 is controlled so as to communicate the hot water supply heat exchanger 32 and the bottom of the hot water storage tank 41.

次に、室外気温が低く蒸発器３４に霜が生成し、その霜を溶かす除霜運転を行う場合、循環ポンプ４３、ファン３５を停止し、給湯運転を停止し、減圧手段３３を開き、給湯用熱交換器３２での吐出冷媒の放熱をできるだけ防ぎ、高温高圧の冷媒を蒸発器３４に流し、蒸発器３４の温度を上昇させ除霜する。 Next, when the outdoor temperature is low and frost is generated in the evaporator 34 and the defrosting operation is performed to melt the frost, the circulation pump 43 and the fan 35 are stopped, the hot water supply operation is stopped, the decompression means 33 is opened, The heat of the discharged refrigerant in the heat exchanger 32 is prevented as much as possible, and a high-temperature and high-pressure refrigerant is passed through the evaporator 34 to increase the temperature of the evaporator 34 and defrost.

この時、三方弁４４は給湯用熱交換器３２と貯湯槽４１底部を連通させるように制御し、運転される。除霜運転中は蒸発器３４に高温の冷媒を流入させて除霜を行うため、冷媒は吸熱して蒸発することができず、液冷媒の状態で圧縮機３１に吸入され、圧縮機３１から吸熱して蒸発するため、圧縮機３１の吐出温度は次第に低下する。 At this time, the three-way valve 44 is controlled and operated so as to communicate the hot water supply heat exchanger 32 and the bottom of the hot water storage tank 41. During the defrosting operation, a high-temperature refrigerant is introduced into the evaporator 34 to perform defrosting. Therefore, the refrigerant cannot absorb heat and evaporate, and is sucked into the compressor 31 in a liquid refrigerant state. Since it absorbs heat and evaporates, the discharge temperature of the compressor 31 gradually decreases.

その結果、給湯用熱交換器３２には圧縮機３１の吐出冷媒が流れるため、給湯熱交換器３２の温度は吐出冷媒温度と同じ温度となる。蒸発器３４の霜が溶け、蒸発器３４出口配管の冷媒温度が上昇し、蒸発器出口温度センサーの出力値が設定値（例えば５℃）以上となると、除霜運転は終了し、循環ポンプ４３、ファン３５が運転され、入水温度、室外気温、吐出冷媒温度と出湯目標温度により、圧縮機３１の運転周波数および、減圧手段３３の初期開度Ｐ１はあらかじめ設定されたテーブルから選択され、決定され、給湯運転が再開される。 As a result, since the refrigerant discharged from the compressor 31 flows through the hot water supply heat exchanger 32, the temperature of the hot water supply heat exchanger 32 is the same as the temperature of the discharged refrigerant. When the frost of the evaporator 34 is melted, the refrigerant temperature of the outlet pipe of the evaporator 34 rises, and the output value of the evaporator outlet temperature sensor becomes a set value (for example, 5 ° C.) or more, the defrosting operation is finished, and the circulation pump 43 The fan 35 is operated, and the operating frequency of the compressor 31 and the initial opening degree P1 of the decompression means 33 are selected and determined from a preset table according to the incoming water temperature, outdoor air temperature, discharged refrigerant temperature and hot water target temperature. The hot water supply operation is resumed.

この時、三方弁４４は給湯用熱交換器３２と貯湯槽上部の温水戻り口４５を連通させるように制御され、湯は貯湯槽４１の上部に流入する。この時の湯温は、給湯設定温度（例えば８０℃）より低いが、圧縮機３１や給湯用熱交換器３２の温度はすぐに上昇し、湯温も上昇する。 At this time, the three-way valve 44 is controlled so that the hot water supply heat exchanger 32 and the hot water return port 45 at the upper part of the hot water storage tank communicate with each other, and hot water flows into the upper part of the hot water storage tank 41. The hot water temperature at this time is lower than the hot water supply set temperature (for example, 80 ° C.), but the temperatures of the compressor 31 and the hot water heat exchanger 32 rise immediately, and the hot water temperature also rises.

その結果、除霜運転時に三方弁４４を貯湯槽４１底部と連通するように切り替えるため、貯湯槽の高温の湯が逆流し、高温の湯が貯湯槽４１底部に流入することを防止し、また、給湯運転再開後もすぐに三方弁４４を切り替え、貯湯槽上部の温水戻り口４５に連通させるため、貯湯槽４１底部の水温上昇を防止することができるため、エネルギー効率の高い給湯運転を行うことができる。 As a result, since the three-way valve 44 is switched to communicate with the bottom of the hot water storage tank 41 during the defrosting operation, hot water in the hot water storage tank flows backward, preventing hot hot water from flowing into the bottom of the hot water storage tank 41, and Since the three-way valve 44 is switched immediately after the hot water supply operation is resumed and communicated with the hot water return port 45 at the upper part of the hot water tank, the water temperature rise at the bottom of the hot water tank 41 can be prevented. be able to.

以上のように、本発明にかかるヒートポンプ給湯装置は、エネルギー効率の高い給湯運転が可能となるため、高温の湯を利用した空調機等の用途にも適用できる。 As described above, the heat pump hot water supply apparatus according to the present invention can perform hot water supply operation with high energy efficiency, and thus can be applied to uses such as an air conditioner using high-temperature hot water.

本発明の実施の形態１におけるのヒートポンプ給湯装置の構成図The block diagram of the heat pump hot-water supply apparatus in Embodiment 1 of this invention 従来のヒートポンプ給湯装置の構成図Configuration diagram of conventional heat pump water heater

符号の説明Explanation of symbols

３１圧縮機
３２給湯用熱交換器
３３減圧手段
３４蒸発器
３５ファン
４１貯湯槽
４２貯湯槽下部の取水口
４３循環ポンプ
４４三方弁
４５貯湯槽上部の温水戻り口
４６給湯回路
４７バイパス回路
５１入水温度センサー
５２出湯温度センサー
５３室外気温センサー
５４吐出温度センサー
５５蒸発器出口温度センサー
５６制御装置
31 Compressor 32 Heat exchanger for hot water supply 33 Depressurization means 34 Evaporator 35 Fan 41 Hot water storage tank 42 Water intake port at the bottom of the hot water storage tank 43 Circulation pump 44 Three-way valve 45 Hot water return port at the top of the hot water storage tank 46 Hot water supply circuit 47 Bypass circuit 51 Incoming water temperature Sensor 52 Hot water temperature sensor 53 Outdoor air temperature sensor 54 Discharge temperature sensor 55 Evaporator outlet temperature sensor 56 Control device

Claims

圧縮機、給湯用熱交換器、減圧手段、蒸発器を順次接続した冷媒回路と、貯湯槽の下部から循環ポンプを介して、前記給湯用熱交換器、三方弁を通過し、前記貯湯槽の上部へと水を循環させる給湯回路と、前記三方弁と前記貯湯槽の下部と接続するバイパス回路とを備え、前記循環ポンプの停止時または前記循環ポンプによる低流量運転時、前記給湯用熱交換器と前記貯湯槽の下部とが連通するように、前記三方弁を制御することを特徴するヒートポンプ給湯装置。 A refrigerant circuit in which a compressor, a hot water supply heat exchanger, a decompression unit, and an evaporator are sequentially connected, and a hot water supply heat exchanger and a three-way valve from the lower part of the hot water storage tank through a circulation pump, A hot water supply circuit for circulating water to the upper part, and a bypass circuit connected to the three-way valve and the lower part of the hot water storage tank, and the heat exchange for hot water supply when the circulation pump is stopped or when the circulating pump is operated at a low flow rate A heat pump hot water supply apparatus, wherein the three-way valve is controlled so that a vessel communicates with a lower part of the hot water tank.

給湯用熱交換器を流出する給湯水の温度を検知する出湯温度センサーを有し、前記出湯温度センサーの検知温度が目標値より低い場合には、前記給湯用熱交換器と前記貯湯槽の下部とが連通するように、三方弁を制御することを特徴とする請求項１記載のヒートポンプ給湯装置。 A hot water temperature sensor for detecting the temperature of hot water flowing out of the hot water heat exchanger, and when the temperature detected by the hot water temperature sensor is lower than a target value, the lower part of the hot water heat exchanger and the hot water storage tank The heat pump hot water supply apparatus according to claim 1, wherein the three-way valve is controlled so as to communicate with each other.

給湯用熱交換器を流出する給湯水の温度を検知する出湯温度センサーを有し、前記出湯温度センサーの検知温度が目標値以上の場合には、前記給湯用熱交換器と前記貯湯槽の上部とが連通するように、三方弁を制御することを特徴とする請求項１または２記載のヒートポンプ給湯装置。 A hot water temperature sensor that detects the temperature of hot water flowing out of the hot water heat exchanger, and when the detected temperature of the hot water temperature sensor is equal to or higher than a target value, the hot water heat exchanger and the upper part of the hot water storage tank The heat pump hot-water supply apparatus according to claim 1 or 2, wherein the three-way valve is controlled so as to communicate with each other.

給湯運転終了時は、給湯用熱交換器と貯湯槽の下部とが連通するように、三方弁を制御することを特徴とする請求項１〜３のいずれか１項に記載のヒートポンプ給湯装置。 The heat pump hot water supply apparatus according to any one of claims 1 to 3, wherein the three-way valve is controlled so that the hot water supply heat exchanger and the lower part of the hot water storage tank communicate with each other at the end of the hot water supply operation.

除霜運転中は、給湯用熱交換器と貯湯槽の下部とが連通するように、三方弁を制御することを特徴する請求項１〜４のいずれか１項に記載のヒートポンプ給湯装置。 The heat pump hot water supply apparatus according to any one of claims 1 to 4, wherein the three-way valve is controlled so that the hot water supply heat exchanger and the lower part of the hot water storage tank communicate with each other during the defrosting operation.

除霜運転終了後は、給湯用熱交換器と貯湯槽の上部とが連通するように、三方弁を制御することを特徴とする請求項５記載のヒートポンプ給湯装置。 The heat pump hot water supply apparatus according to claim 5, wherein the three-way valve is controlled so that the hot water supply heat exchanger and the upper part of the hot water storage tank communicate with each other after completion of the defrosting operation.

冷媒として炭酸ガスを用いたことを特徴とする請求項１〜６のいずれか１項に記載のヒートポンプ給湯装置。 The heat pump hot water supply apparatus according to any one of claims 1 to 6, wherein carbon dioxide gas is used as the refrigerant.