JP3906700B2

JP3906700B2 - Heat pump type water heater

Info

Publication number: JP3906700B2
Application number: JP2002023863A
Authority: JP
Inventors: 英樹石田
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2002-01-31
Filing date: 2002-01-31
Publication date: 2007-04-18
Anticipated expiration: 2022-01-31
Also published as: JP2003222401A

Description

【０００１】
【発明の属する技術分野】
本発明は、給湯温水とは異なる温度のブラインを床暖房装置等の放熱機器に供給して、給湯機能の他に床暖房等の放熱機能をも発揮できる多機能型ヒートポンプ式給湯装置に関するものである。
【０００２】
【従来の技術】
従来、ヒートポンプ式給湯装置においては、ヒートポンプユニットを温水の熱源機器として設け、ヒートポンプユニットの高圧側熱交換器（水−冷媒熱交換器）にて加熱された高温水を給湯対象機器に供給するようにしている。ところで、近年、住宅においては、給湯機能の他に床暖房、浴室暖房等の放熱機器へのニーズが高くなっている。
【０００３】
そこで、本発明者らは給湯機能の他に床暖房等の放熱機能を発揮できる多機能型ヒートポンプ式給湯装置を開発中である。
【０００４】
この開発中の給湯装置では、貯湯タンク下部からの低温の温水をヒートポンプユニットの高圧側熱交換器に導入して加熱し、高温水を作り、この高温水を貯湯タンクの上部に流入させる。そして、給湯時には貯湯タンク上部の高温水を給湯対象機器に供給するようにしている。
【０００５】
一方、貯湯タンク上部からの高温水とブラインとを熱交換するブライン加熱用熱交換器（水−水熱交換器）を設け、このブライン加熱用熱交換器で加熱されたブラインを床暖房装置等の放熱機器に循環して、放熱機器の放熱作用を得るようにしている。ここで、ブラインとは床暖房装置等の放熱機器で放熱を行う熱媒体であり、具体的には水道水や、不凍液等を混合した水道水等を使用できる。
【０００６】
【発明が解決しようとする課題】
ところで、ヒートポンプユニットは電気料金の安い深夜に主に稼働して、貯湯タンク内の低温水を９０℃程度の高温水に沸き上げて、貯湯タンク内に高温水を貯留する。そして、昼間に給湯対象機器を使用すると、貯湯タンク上部の高温水が給湯対象機器に供給されるので、その温水供給分（給湯分）だけ、給水配管から低温の水道水が貯湯タンク下部に導入され、貯湯タンク下部には低温水が溜まっていく。
【０００７】
ここで、貯湯タンクは通常、３００Ｌ（本明細書では、Ｌはリットルを表す）程度の容量を有する縦長形状になっており、そして、タンク上部に高温水が流入し、タンク上部に低温水が給水されるので、タンク上部に比してタンク下部の方で温水温度が低下する温度勾配を形成する。
【０００８】
一方、ブライン加熱用熱交換器でブラインと熱交換した後の温水は、熱交換前の８０℃〜９０℃程度の高温から温度低下するものの、依然として４５℃程度の中間温度を維持している。このため、この４５℃程度の中温水をそのまま貯湯タンク下部に戻すと、貯湯タンク下部に溜まっている給水通路からの低温水（例えば、冬期であれば５℃程度）と中温水との撹拌が生じて、貯湯タンク内の温度勾配の境界層が破壊され、貯湯タンク下部の低温水の温度が上昇する。
【０００９】
このため、次回のヒートポンプユニットの運転時（沸き上げ運転時）に、ヒートポンプユニットの高圧側熱交換器の水入口側に導入される給水温度が上昇して、高圧側熱交換器における冷媒温度と給水温度との温度差が減少し、ヒートポンプユニットの効率（ＣＯＰ）を低下させる。
【００１０】
本発明は上記点に鑑みて、多機能給型ヒートポンプ式湯装置において、ヒートポンプユニットの給水温度上昇による効率低下を抑制することを目的とする。
【００１１】
【課題を解決するための手段】
上記目的を達成するため、請求項１に記載の発明では、高圧側熱交換器（１３）にて温水を加熱するヒートポンプユニット（１０）と、高圧側熱交換器（１３）の温水出口側にタンク上部が並列接続され、高圧側熱交換器（１３）の水入口側にタンク下部が並列接続される少なくとも２つの貯湯タンク（１６、１７、１７０）と、少なくとも２つの貯湯タンク（１６、１７、１７０）のうち、第１貯湯タンク（１６）上部の高温水を給湯対象機器（２４）に供給する給湯通路（２３）と、少なくとも第１貯湯タンク（１６）の下部に給水する第１給水通路（２０）と、少なくとも２つの貯湯タンク（１６、１７、１７０）のうち、第２貯湯タンク（１７、１７０）上部の高温水とブラインとを熱交換するブライン加熱用熱交換器（３０、３００）と、ブライン加熱用熱交換器（３０、３００）にて加熱されたブラインを放熱機器（３２、３２０）に循環させるブライン循環回路（３３、３３０）とを備え、ブライン加熱用熱交換器（３０、３００）を通過することにより放熱した中温水を第２貯湯タンク（１７、１７０）の下部に戻すようになっており、更に、第１貯湯タンク（１６）の下部と第２貯湯タンク（１７、１７０）の下部とを連通する連通路（１８）に、両貯湯タンク（１６）（１７、１７０）間の連通を遮断する遮断手段（２１、２１’）を備え、
遮断手段（２１、２１’）は、第１貯湯タンク（１６）上部の高温水を給湯対象機器（２４）へ給湯する時および第２貯湯タンク（１７、１７０）の下部に中温水が戻る時に両貯湯タンク（１６）（１７、１７０）の下部相互間の連通を遮断することを特徴とする。
【００１２】
これにより、並列接続される少なくとも２つの貯湯タンク（１６、１７、１７０）のうち、第１貯湯タンク（１６）上部の高温水を給湯対象機器（２４）に供給する給湯機能を発揮するとともに、第２貯湯タンク（１７、１７０）上部の高温水で加熱されたブラインを放熱機器（３２、３２０）に循環して、放熱機器（３２、３２０）での放熱機能（床暖房機能等）を発揮できる。
【００１３】
また、本発明によると、第１貯湯タンク（１６）上部の高温水を給湯対象機器（２４）に給湯すると第１貯湯タンク（１６）下部に低温水（例えば、５℃）が給水され、一方、ブラインとの熱交換で温度低下した中温水（例えば、４５℃）が第２貯湯タンク（１７、１７０）の下部に戻ることになるが、その際、連通路（１８）に備えた遮断手段（２１、２１’）により両貯湯タンク（１６）（１７、１７０）の下部相互間の連通を遮断することができるので、第１貯湯タンク（１６）下部への低温水の貯留と、第２貯湯タンク（１７、１７０）下部への中温水の貯留とを別々に分けて行うことができる。
【００１４】
従って、次回のヒートポンプユニット（１０）の沸き上げ運転時に、低温水と中温水が混合して温度上昇した水がヒートポンプユニット（１０）の高圧側熱交換器（１３）の水入口側に給水されることを防止して、第１貯湯タンク（１６）下部の低温水を低温状態のまま高圧側熱交換器（１３）に給水でき、ヒートポンプユニットの効率（ＣＯＰ）を向上できる。
【００１６】
請求項２に記載の発明のように、請求項１において、具体的には、ヒートポンプユニット（１０）の運転により両貯湯タンク（１６）（１７、１７０）内の温水を沸き上げるときに、第１貯湯タンク（１６）の下部の水温度が第２貯湯タンク（１７、１７０）の下部の水温度より低い間は遮断手段（２１、２１’）により両貯湯タンク（１６）（１７、１７０）の下部相互間の連通を遮断し、第１貯湯タンク（１６）の下部の水を高圧側熱交換器（１３）の水入口側に供給し、
温水の沸き上げ時に、第１貯湯タンク（１６）の下部の水温度と第２貯湯タンク（１７、１７０）の下部の水温度とが同等の温度であるときは、遮断手段（２１、２１’）を、両貯湯タンク（１６）（１７、１７０）の下部相互間の連通状態に切り替え、両貯湯タンク（１６）（１７、１７０）の下部の水を高圧側熱交換器（１３）の水入口側に供給するようにする。
【００１７】
請求項３に記載の発明では、請求項１または２において、両貯湯タンク（１６）（１７、１７０）と高圧側熱交換器（１３）間で温水を循環させる循環ポンプ（２２）を備え、
循環ポンプ（２２）による温水循環流量を、両貯湯タンク（１６）（１７、１７０）間での温水温度差による自然対流の温水循環流量より小さくしたことを特徴とする。
【００１８】
ところで、第１、第２貯湯タンク（１６、１７、１７０）は並列接続されているので、両タンクの下部相互間が連通している状態では、両タンク間での温水温度差により自然対流の温水循環が発生する。
請求項３ではこの点に着目して温水循環用の循環ポンプ（２２）の温水循環流量を両タンク間の自然対流の温水循環流量より小さくしているから、循環ポンプ（２２）のポンプ作用による温水流れよりも自然対流の温水流れの方が上回ることになる。
【００１９】
この結果、第１貯湯タンク（１６）下部に低温水が貯留され、第２貯湯タンク（１７、１７０）下部に中温水が貯留されている状態において両タンクの下部相互間を連通して、ヒートポンプユニット（１０）の沸き上げ運転を行っても、循環ポンプ（２２）は低温水のみを選択的に吸引して、高圧側熱交換器（１３）の水入口側に送ることができる。
【００２０】
請求項３によると、ヒートポンプユニット（１０）の沸き上げ運転時に、遮断手段（２１、２１’）を両タンクの下部相互間の連通状態に維持したままにすることができる。従って、沸き上げ運転時に遮断手段（２１、２１’）の連通、遮断の切替を行う必要がない。
【００２１】
請求項４に記載の発明では、請求項１ないし３のいずれか１つにおいて、遮断手段は、第１給水通路（２０）と連通路（１８）を切替開閉する三方弁（２１）から構成され、
三方弁（２１）は、両貯湯タンク（１６）（１７、１７０）の下部相互間の連通を遮断し、第１給水通路（２０）を第１貯湯タンク（１６）の下部に連通する第１作動状態と、両貯湯タンク（１６）（１７、１７０）の下部相互間を連通し、第１給水通路（２０）を閉塞する第２作動状態を少なくとも切り替えるように構成されていることを特徴とする。
【００２２】
これにより、１つの三方弁（２１）により第１貯湯タンク（１６）下部への給水と両貯湯タンクの下部相互間の連通とを切り替えることができる。そのため、第１貯湯タンク（１６）下部に第１給水通路（２０）を直接接続する場合（下記の請求項５）に比較して第１貯湯タンク（１６）下部の水通路構成を簡素化できる。
【００２３】
請求項５に記載の発明のように、請求項１ないし３のいずれか１つにおいて、第１給水通路（２０）を第１貯湯タンク（１６）の下部に直接接続し、遮断手段を連通路（１８）を開閉する開閉弁（２１’）により構成してもよい。
【００２４】
請求項６に記載の発明では、請求項１ないし５のいずれか１つにおいて、第２貯湯タンク（１７、１７０）下部の中温水を給湯通路（２３）に供給する中温水供給通路（２５）を備えることを特徴とする。
【００２５】
これにより、第２貯湯タンク（１７、１７０）下部に溜まる中温水を積極的に給湯のために有効利用できる。
【００２６】
その結果、給湯時に両貯湯タンク上部の高温水の使用を節約できると同時に、ヒートポンプユニット（１０）の次回の沸き上げ運転までに中温水の残存量を減らすことができる。この中温水の残存量が減少する分だけ、貯湯タンク下部における低温水の貯留量が増加するので、次回の沸き上げ運転時には中温水の沸き上げの確率が減少して、低温水の沸き上げの確率が増加するから、ヒートポンプユニットの効率（ＣＯＰ）向上にとってより一層有利である。
【００２７】
請求項７に記載の発明では、高圧側熱交換器（１３）にて温水を加熱するヒートポンプユニット（１０）と、高圧側熱交換器（１３）の温水出口側にタンク上部が並列接続され、高圧側熱交換器（１３）の水入口側にタンク下部が並列接続される少なくとも２つの貯湯タンク（１６、１７、１７０）と、少なくとも２つの貯湯タンク（１６、１７、１７０）のうち、第１貯湯タンク（１６）上部の高温水を給湯対象機器（２４）に供給する給湯通路（２３）と、少なくとも第１貯湯タンク（１６）の下部に給水する第１給水通路（２０）と、少なくとも２つの貯湯タンク（１６、１７、１７０）のうち、第２貯湯タンク（１７、１７０）上部の高温水とブラインとを熱交換するブライン加熱用熱交換器（３０、３００）と、ブライン加熱用熱交換器（３０、３００）にて加熱されたブラインを放熱機器（３２、３２０）に循環させるブライン循環回路（３３、３３０）とを備え、ブライン加熱用熱交換器（３０、３００）を通過することにより放熱した中温水を第２貯湯タンク（１７、１７０）の下部に戻すようになっており、更に、第２貯湯タンク（１７、１７０）下部の中温水を給湯通路（２３）に供給する中温水供給通路（２５）を備えることを特徴とする。
【００２８】
これにより、請求項１と同様に、第１貯湯タンク（１６）上部の高温水を給湯対象機器（２４）に供給する給湯機能を発揮するとともに、第２貯湯タンク（１７、１７０）上部の高温水で加熱されたブラインを放熱機器（３２、３２０）に循環して、放熱機器（３２、３２０）での放熱機能（床暖房機能等）を発揮できる。
【００２９】
しかも、請求項７によると、第２貯湯タンク（１７、１７０）下部に溜まる中温水を積極的に給湯のために有効利用できるので、給湯時に両貯湯タンク上部の高温水の使用を節約できると同時に、ヒートポンプユニット（１０）の次回の沸き上げ運転までに中温水の残存量を減らすことができる。
この中温水の残存量の減少により請求項６と同様に、次回の沸き上げ運転時には中温水の沸き上げの確率が減少して、低温水の沸き上げの確率が増加するから、ヒートポンプユニットの効率（ＣＯＰ）を向上できる。
【００３０】
請求項８に記載の発明では、請求項６または７において、給湯通路（２３）に給水する第２給水通路（２８）と、給湯通路（２３）への第２給水通路（２８）からの給水と、給湯通路（２３）への中温水供給通路（２５）からの中温水供給を切り替える切替手段（２６）とを備えることを特徴とする。
【００３１】
これにより、給湯通路（２３）に第２給水通路（２８）からの低温給水と中温水供給通路（２５）からの中温水とを切り替えて給湯対象機器（２４）に供給できる。そのため、第１貯湯タンク（１６）上部からの高温水と、第２給水通路（２８）からの低温給水または中温水供給通路（２５）からの中温水との混合比率を調整して、給湯対象機器（２４）への給湯温度を調整できる。
【００３２】
請求項９に記載の発明では、請求項１ないし８のいずれか１つにおいて、第２貯湯タンク（１７、１７０）にブライン加熱用熱交換器（３０、３００）を複数個並列接続し、ブライン循環回路として、複数個のブライン加熱用熱交換器（３０、３００）にそれぞれ対応する複数個のブライン循環回路（３３、３３０）を設け、放熱機器として、複数個のブライン循環回路（３３、３３０）にそれぞれ対応する複数個の放熱機器（３２、３２０）を設け、複数個のブライン加熱用熱交換器（３０、３００）をそれぞれ通過した中温水のうち、温度の低い方の中温水を第２貯湯タンク（１７、１７０）の下部に戻し、中温水のうち、温度の高い方の中温水を第２貯湯タンク（１７、１７０）に対して温度の低い方の中温水の戻り位置よりも高い位置に戻すことを特徴とする。
【００３３】
これにより、複数個のブライン加熱用熱交換器（３０、３００）をそれぞれ通過した温度の異なる中温水を第２貯湯タンク（１７、１７０）に戻す場合に、第２貯湯タンク（１７、１７０）の下部に温度の低い方の中温水を溜め、第２貯湯タンク（１７、１７０）の中間部に温度の高い方の中温水を溜めることができる。従って、温度の低い中温水と温度の高い中温水が第２貯湯タンク（１７、１７０）で混合して、温度の低い方の中温水の温度が上昇することを防止でき、ヒートポンプユニットの効率（ＣＯＰ）向上の点から有利である。
【００３４】
請求項１０に記載の発明のように、請求項９において、複数個の放熱機器の１つは具体的には床暖房装置（３２）であり、他の１つは具体的には浴室暖房装置（３２０）である。
【００３５】
これにより、給湯機能の他に、床暖房機能および浴室暖房機能を発揮できる。
【００３６】
請求項１１に記載の発明のように、請求項１ないし１０のいずれか１つにおいて、ヒートポンプユニット（１０）を、高圧側圧力が冷媒の臨界圧力以上となる超臨界冷凍サイクルにて構成すれば、超臨界冷凍サイクルの効率（ＣＯＰ）向上を効果的に達成できる。
【００３７】
なお、上記各手段の括弧内の符号は、後述する実施形態に記載の具体的手段との対応関係を示すものである。
【００３８】
【発明の実施の形態】
（第１実施形態）
第１実施形態は、本発明を一般家庭用の多機能型ヒートポンプ式給湯装置に適用したものであって、図１は給湯装置の全体構成図であり、給湯装置の構成は、温水熱源をなすヒートポンプユニット１０と、ヒートポンプユニット１０で加熱された高温水を蓄える貯湯タンクユニット１１とに大別される。
【００３９】
ヒートポンプユニット１０は冷媒としてＣＯ₂を用い、高圧側圧力が冷媒の臨界圧力以上となる超臨界冷凍サイクルにて構成されている。ヒートポンプユニット１０は回転数を制御可能な電動圧縮機１２を有し、この電動圧縮機１２にて圧縮された高圧冷媒を加熱用高圧側熱交換器１３に流入させる。この高圧側熱交換器１３は高圧冷媒と水とを熱交換して水を加熱する水−冷媒熱交換器を構成する。この高圧側熱交換器１３を通過した放熱後の高圧冷媒はその後、減圧装置１４で低圧状態に減圧される。
【００４０】
この低圧冷媒は低圧側（吸熱用）熱交換器を構成する蒸発器１５に流入し、この蒸発器１５で大気から吸熱して蒸発し、その後、電動圧縮機１２に冷媒が吸入され再度圧縮される。ヒートポンプユニット１０は料金の安い夜間電力を利用して主に夜間に稼働されて温水を加熱する電気式の熱源機器を構成する。
【００４１】
貯湯タンクユニット１１は縦長の第１貯湯タンク１６および第２貯湯タンク１７を有している。この第１、第２貯湯タンク１６、１７は本例では同一容量であり、例えば、１５０Ｌ（リットル）程度の容量である。この第１、第２貯湯タンク１６、１７はヒートポンプユニット１０の高圧側熱交換器１３の温水循環回路中に並列接続される。
【００４２】
すなわち、第１、第２貯湯タンク１６、１７の最上部に設けてある上部接続口１６ａ，１７ａは高圧側熱交換器１３の温水出口側に並列接続され、また、第１貯湯タンク１６の最下部に設けてある下部接続口１６ｂと、第２貯湯タンク１７の最下部に設けてある下部接続口１７ｂは高圧側熱交換器１３の水入口側（給水側）に並列接続される。
【００４３】
より具体的には、第１貯湯タンク１６の下部接続口１６ｂと第２貯湯タンク１７の下部接続口１７ｂを連通する連通路１８の中間部位をヒートポンプ入口通路１９により高圧側熱交換器１３の水入口側に連通するとともに、連通路１８のうち、ヒートポンプ入口通路１９の分岐位置よりも第２貯湯タンク１７側の部位に、第１貯湯タンク１６の下部接続口１６ｂに水道水を給水するための第１給水通路２０を合流し、この合流点に第１三方弁２１が設けられている。
【００４４】
この第１三方弁２１は本発明の遮断手段を構成するものであって、モータ等のアクチュエータにより弁体を駆動する電気制御弁である。本例の第１三方弁２１は、弁体位置の切替により次の３つの作動状態を選択できるようになっている。
【００４５】
すなわち、第１三方弁２１は、第１、第２貯湯タンク１６、１７の下部相互間の連通を遮断し、第１給水通路２０を第１貯湯タンク１６の下部接続口１６ｂに連通する第１作動状態と、第１、第２貯湯タンク１６、１７の下部相互間を連通し、第１給水通路２０を閉塞する第２作動状態と、第１、第２貯湯タンク１６、１７の下部相互間の連通を遮断し、第１給水通路２０を第２貯湯タンク１７の下部接続口１７ｂに連通する第３作動状態とを切り替えるようになっている。
【００４６】
ヒートポンプ入口通路１９には電動式の循環ポンプ２２が設置され、この循環ポンプ２２の作動によって第１、第２貯湯タンク１６、１７とヒートポンプユニット１０の高圧側熱交換器１３との間の温水循環を行うようになっている。ここで、ヒートポンプユニット１０の高圧側熱交換器１３にて温水を９０℃付近の高温に加熱するためには、温水の循環流量を絞る必要があるため、循環ポンプ２２の循環流量は本例では０．６〜１．０Ｌ／分程度の微小流量に設定してある。
【００４７】
一方、第１貯湯タンク１６の最上部には温水出口１６ｄを設け、この温水出口１６ｄに給湯通路２３が接続してあり、この給湯通路２３を通して台所、洗面所、風呂等の給湯対象機器２４に給湯するようになっている。
【００４８】
この給湯通路２３に、第２貯湯タンク１７の下部に溜まる後述の中温水を供給するための中温水供給通路２５が合流している。より具体的には、中温水供給通路２５の途中に電磁弁等の電気制御弁からなる第２三方弁２６を設け、中温水供給通路２５のうち、第２三方弁２６の下流側の通路を給湯通路２３の途中に合流している。そして、この合流点に温度調整弁２７を配置している。
【００４９】
第２三方弁２６には第２給水通路２８が接続され、中温水供給通路２５の中温水と第２給水通路２８からの水道水とを温度調整弁２７に切替導入する。温度調整弁２７は、給湯通路２３からの高温水と、中温水供給通路２５の中温水または第２給水通路２８からの低温水道水との混合比率を調整して給湯温度を調整する。
【００５０】
なお、本例の温度調整弁２７は上記混合比率を調整する弁体をモータ等のアクチュエータにより駆動するようになっており、温度調整弁２７の下流側通路には給湯温水の温度を検出する温度センサ２９が配置され、この温度センサ２９により検出される給湯温水の温度が使用者の設定した目標温度となるように弁体位置を自動調整する。これにより、給湯温水の温度が目標温度に維持される。
【００５１】
一方、第２貯湯タンク１７にはブライン加熱用熱交換器３０が接続してある。このブライン加熱用熱交換器３０は、第２貯湯タンク１７の上部から高温水が流入する温水通路部３０ａと、この温水通路部３０ａ内の高温水と熱交換して加熱されるブラインが通過するブライン通路部３０ｂとを備えている。温水通路部３０ａの出口部は第２貯湯タンク１７の下部に接続され、温水通路部３０ａにてブラインと熱交換して温度低下した中温水（例えば、４５℃程度の温水）が第２貯湯タンク１７の下部に戻る。温水通路部３０ａの出口側に設けた電動式の循環ポンプ３１により第２貯湯タンク１７と温水通路部３０ａとの間で温水が循環する。
【００５２】
また、ブライン通路部３０ｂは、ブラインの放熱機器をなす床暖房装置３２に接続されてブライン循環回路３３を構成する。このブライン循環回路３３において、ブライン通路部３０ｂの入口側に電動式の循環ポンプ３４を設け、この循環ポンプ３４によりブライン通路部３０ｂで加熱されたブラインが床暖房装置３２に循環する。ここで、ブラインは、熱交換器３０内で加熱され、床暖房装置３２にて放熱する熱媒体であり、具体的には、水道水や、不凍液を混合した水道水等を使用できる。
【００５３】
また、縦長形状の第１、第２貯湯タンク１６、１７では、タンク上下方向には温水の温度勾配が形成される。そこで、第１、第２貯湯タンク１６、１７における上下方向の温水温度の勾配を判定できるようにするため、第１、第２貯湯タンク１６、１７にはそれぞれ、タンク上下方向の異なる高さに複数の温度センサ３５ａ、３５ｂ、３５ｃ、３６ａ、３６ｂ、３６ｃを設けて、タンク上下方向の異なる高さの温水温度を検出するようになっている。図示の例では、第１、第２貯湯タンク１６、１７にそれぞれ、上中下の３箇所に温度センサ３５ａ〜３５ｃ、３６ａ〜３６ｃを設けている。
【００５４】
また、第１、第２給水通路２０、２８に供給される水道水の温度を検出する温度センサ３７が備えられている。図１では第２給水通路２８側の部位に温度センサ３７を図示している。
【００５５】
次に、第１実施形態の電気制御の概略構成を図２により説明すると、電子制御装置３８はマイクロコンピュータとその周辺回路とにより構成されるものであって、予め設定されたプログラムに基づく所定の演算処理を行って、給湯装置の各種機器の作動を制御するようになっている。
【００５６】
電子制御装置３８の入力側には、温度センサ２９、３５ａ〜３５ｃ、３６ａ〜３６ｃ、３７等のセンサ検出信号が入力される。また、給湯装置操作パネル３９の各種操作スイッチ（図示省略）の操作信号が電子制御装置３８の入力側に入力される。給湯装置操作パネル３９の操作スイッチとして、前述の給湯温水の目標温度を設定する温度設定スイッチ等が備えられる。
【００５７】
一方、電子制御装置３８の出力側には、ヒートポンプユニット１１の電動圧縮機１２、循環ポンプ２２、３１、３４、第１、第２三方弁２１、２６、温度調整弁２７等の機器が接続され、これらの機器の作動を電子制御装置３８の出力により制御するようになっている。
【００５８】
次に、第１実施形態の作動を説明すると、ヒートポンプユニット１０は主に夜間（深夜）電力を利用して運転され、循環ポンプ２２により高圧側熱交換器１３に流入する水を高圧側熱交換器１３にて加熱し、９０℃程度の高温水に沸き上げる。
【００５９】
図３はヒートポンプユニット１０の夜間における沸き上げ運転により第１、第２貯湯タンク１６、１７内の下部まで９０℃程度の高温水が充満した沸き上げ完了状態を示している。この沸き上げ完了状態は、第１、第２貯湯タンク１６、１７下部の温度センサ３５ｃ、３６ｃの検出温度に基づいて判定できる。すなわち、この温度センサ３５ｃ、３６ｃの検出温度が予め定めた所定温度まで上昇したことを電子制御装置３８で判定することにより沸き上げ完了を判定できる。
【００６０】
電子制御装置３８が沸き上げ完了を判定すると、電動圧縮機１２を停止し、ヒートポンプユニット１１の運転を停止する。また、沸き上げ完了を判定すると、電子制御装置３８は第１三方弁２１を第１作動状態にする。すなわち、第１三方弁２１は、第２貯湯タンク１７の下部接続口１７ｂ側の通路を遮断し、第１給水通路２０を第１貯湯タンク１６の下部接続口１６ｂ側に連通する第１作動状態となる。第１三方弁２１は、この第１作動状態を以後、次回の沸き上げ運転になるまで維持する。
【００６１】
図４は図３の状態から給湯対象機器２４に給湯して、第１貯湯タンク１６内の９０℃の高温水をタンク容量の半分（７５Ｌ）程度使用した後の状態を示す。この給湯時には第１三方弁２１が上記第１作動状態を維持しているので、給湯対象機器２４にて出湯すると、第１給水通路２０の低温（本例では５℃）の水道水が第１三方弁２１、連通路１８を通過して第１貯湯タンク１６の下部接続口１６ｂから第１貯湯タンク１６内に流入する。
【００６２】
一方、第２貯湯タンク１７の下部接続口１７ｂは第１三方弁２１により閉塞されているので、第１給水通路２０の低温水が第２貯湯タンク１７に流入することはない。また、第２貯湯タンク１７に第１給水通路２０の水道圧が加わらないので、第２貯湯タンク１７内の高温水が給湯に使用されることもない。
【００６３】
次に、給湯温水の温度調整について説明すると、第２貯湯タンク１７からの中温水供給通路２５の途中に設けられている第２三方弁２６は、給湯装置操作パネル３９の温度設定スイッチにより設定される給湯温水の目標温度Ｔｏと、第２貯湯タンク１７下部の温度センサ３６ｃにより検出される温水温度Ｔ３６ｃと、第２給水通路２８の温度センサ３７により検出される給水温度Ｔ３７とに基づいて通路切替作動を行う。具体的には、
▲１▼目標温度Ｔｏ＜第２貯湯タンク下部の温水温度Ｔ３６ｃの関係が成立するときは、この温度関係を電子制御装置３８が判定して電子制御装置３８の出力信号により第２三方弁２６が中温水供給通路２５を遮断し、第２給水通路２８を温度調整弁２７側の通路に連通させる状態となる。
【００６４】
図４は第２貯湯タンク１７の下部まで高温水が充満しているので、上記▲１▼の温度関係が成立する。そのため、第２給水通路２８からの低温水が温度調整弁２７に供給される。従って、図４の状態では、温度調整弁２７にて第２給水通路２８からの低温水と第１貯湯タンク１６上部からの高温水との混合比率を調整して、給湯温水の温度を使用者の設定した目標温度Ｔｏに調整する。
【００６５】
▲２▼目標温度Ｔｏ＞第２貯湯タンク下部の温水温度Ｔ３６ｃ＞給水温度Ｔ３７の関係が成立するときは、温水温度Ｔ３６ｃが目標温度Ｔｏより低く、かつ、給水温度Ｔ３７より高い中温水の状態であるから、この温度関係を電子制御装置３８が判定すると、電子制御装置３８の出力信号により第２三方弁２６は第２給水通路２８を遮断し、中温水供給通路２５を連通状態とする。従って、第２貯湯タンク下部の中温水が中温水供給通路２５を通して温度調整弁２７に供給される。
【００６６】
ところで、図４の給湯使用後の状態から沸き上げ運転を行うときは、第２貯湯タンク１７内が９０℃程度の高温水で充満しているので、第１貯湯タンク１６下部の低温水を沸き上げるのみでよい。そのため、このときは電子制御装置３８の出力信号により第１三方弁２１を前述の第１作動状態に維持したまま（第２貯湯タンク１７の下部接続口１７ｂを遮断したまま）、沸き上げ運転を行う。
【００６７】
次に、図５は図４の給湯使用後の状態から更に床暖房装置３２を使用した後の状態を示す。床暖房装置３２の使用状態を設定すると、電子制御装置３８の出力信号により循環ポンプ３１、３４が作動状態になる。循環ポンプ３１の作動により第２貯湯タンク１７上部の高温水がブライン加熱用熱交換器３０の温水通路部３０ａに流入し、また、循環ポンプ３４の作動によりブライン循環回路３３内のブラインがブライン加熱用熱交換器３０のブライン通路部３０ｂに流入する。
【００６８】
これにより、熱交換器３０において高温水とブラインとが熱交換して、ブラインは例えば６０℃程度の温度に上昇して床暖房装置３２に流入し、床暖房装置３２にて住宅床面に放熱する。この放熱後のブラインは例えば４０℃程度に温度低下してブライン加熱用熱交換器３０のブライン通路部３０ｂに戻る。また、第２貯湯タンク１７からの高温水はブライン加熱用熱交換器３０で放熱して例えば４５℃程度に温度低下して第２貯湯タンク１７の下部に戻る。
【００６９】
このとき、第１三方弁２１は、第２貯湯タンク１７の下部接続口１７ｂを遮断する前述の第１作動状態を維持しているので、ブライン加熱用熱交換器３０からの戻り温水が第１貯湯タンク１６の下部に戻ることはない。
【００７０】
以上により、床暖房装置３２の使用経過につれて、第２貯湯タンク１７の下部にブライン加熱用熱交換器３０からの戻り温水、すなわち、４５℃程度の中温水が次第に溜まっていく。図５は第２貯湯タンク１７の下部にタンク容量の半分程度の中温水が溜まった状態を示す。
【００７１】
次に、図６は図５の床暖房装置使用後の状態から再度、給湯対象機器２４に給湯した状態を示す。図５の床暖房装置使用後の状態では、第２貯湯タンク１７の下部に中温水が溜まっているので、前述の▲２▼の温度関係、すなわち、
目標温度Ｔｏ＞第２貯湯タンク下部の温水温度Ｔ３６ｃ＞給水温度Ｔ３７の関係が成立する。
【００７２】
このため、電子制御装置３８の出力信号により第２三方弁２６は第２給水通路２８を遮断し、中温水供給通路２５を連通状態とする状態に切り替わる。なお、第１三方弁２１は、このときも第２貯湯タンク１７の下部接続口１７ｂを遮断する前述の第１作動状態を維持している。従って、給湯対象機器２４へ給湯すると、第２貯湯タンク下部の中温水が中温水供給通路２５を通して温度調整弁２７に供給される。
【００７３】
これにより、温度調整弁２７は、中温水供給通路２５からの中温水と第１貯湯タンク１６からの高温水との混合比率を調整して、給湯温水を目標温度Ｔｏに調整する。この際、第２貯湯タンク１７下部の中温水を給湯に利用するので、第１貯湯タンク１６上部から給湯通路２３に供給される高温水の量を節約すると同時に、第２貯湯タンク１７下部の中温水の量を積極的に減らすことができる。
【００７４】
そして、第２貯湯タンク１７下部の中温水を給湯に利用することにより、第１貯湯タンク１６上部の高温水が第２貯湯タンク１７の上部に流入し、第１貯湯タンク１６の下部には第１給水通路２０から低温水道水が第１三方弁２１を通過して下部接続口１６ｃから流入する。そのため、第１貯湯タンク１６下部における低温水の比率が増加していく。図６はこのようにして、第１貯湯タンク１６下部の低温水の比率が増加し、第２貯湯タンク１７上部の高温水の比率が増加した状態を示す。
【００７５】
そして、図６の状態から給湯対象機器２４への給湯を更に続行すると、図７に示すように第１貯湯タンク１６内の上部まで低温水が充満し、そして、第２貯湯タンク１７下部の中温水を給湯のために使い切り、第２貯湯タンク１７内の下部まで高温水が充満したり、あるいは、第２貯湯タンク１７内の下部に少量の中温水が残存するする場合が生じる。
【００７６】
このように、第１貯湯タンク１６内の上部まで低温水が充満したことをタンク上部の温度センサ３５ａの検出温度に基づいて電子制御装置３８が判定すると、電子制御装置３８の出力信号により第１三方弁２１を前述の第３作動状態に切り替える。すなわち、第１三方弁２１は、第１、第２貯湯タンク１６、１７の下部相互間の連通を遮断し、第１給水通路２０を第２貯湯タンク１７の下部接続口１７ｂに連通する。
【００７７】
これにより、第２貯湯タンク１７下部に第１給水通路２０の水道圧が加わるので、給湯対象機器２４への給湯を行うと、水道圧により第２貯湯タンク１７内上部から高温水が押し出され、第１貯湯タンク１６の上部を経て給湯通路２３に供給される。
【００７８】
また、第１三方弁２１の切替作動と同時に、電子制御装置３８の出力信号により第２三方弁２６を第２給水通路２８側が開口し、中温水供給通路２５側が閉塞する状態に切り替える。従って、温度調整弁２７は、第２給水通路２８からの低温水と第２貯湯タンク１７からの高温水との混合比率を調整して、給湯温水を目標温度Ｔｏに調整する。
【００７９】
以上のようにして、第２貯湯タンク１７内の高温水を有効利用して給湯対象機器２４への給湯を行うことができる。
【００８０】
次に、前述の図６の給湯再使用後の状態から沸き上げ運転を行う場合を説明すると、この場合は、第１貯湯タンク１６下部の温水温度Ｔ３５ｃ＜第２貯湯タンク１７下部の温水温度Ｔ３６ｃの温度関係を電子制御装置３８により判定して、電子制御装置３８の出力信号により第１三方弁２１を前述の第１作動状態に維持して、このときも第２貯湯タンク１７の下部接続口１７ｂを遮断した状態を維持する。
【００８１】
従って、循環ポンプ２２の作動により第１貯湯タンク１６下部の低温水がヒートポンプユニット１０の高圧側熱交換器１３に流入し、加熱され、この加熱後の高温水が第１貯湯タンク１６の上部に流入する。そして、図８（ａ）に示すように第１貯湯タンク１６の下部まで高温水が充満すると、このことを下部温度センサ３５ｃの検出温度に基づいて電子制御装置３８が判定して、第１三方弁２１を前述の第２作動状態に切り替えて、第２貯湯タンク１７の下部接続口１７ｂを連通路１８を介してヒートポンプ入口通路１９に連通させる。
【００８２】
これにより、第１、第２貯湯タンク１６、１７が循環ポンプ２２の循環回路に並列に接続されるが、以下の理由にて第２貯湯タンク１７下部の中温水（４５℃）のみが選択的に循環ポンプ２２に吸入されるので、４５℃の中温水と９０℃の高温水とが混合して高圧側熱交換器１３の給水温度が上昇するという現象は発生しない。
【００８３】
図８（ａ）に示す状態では、高温水が充満した第１貯湯タンク１６と、中温水がタンク下部に残存している第２貯湯タンク１７とが第１三方弁２１を介して並列接続の状態にあるので、第２貯湯タンク１７下部の中温水と、第２貯湯タンク１７上部および第１貯湯タンク１６全体の高温水との密度差により第１、第２貯湯タンク１６、１７間で温水の自然対流が発生する。
【００８４】
すなわち、密度の大きい中温水が矢印ａのように下方へ移動して第１貯湯タンク１６の下部に流入する。これに伴って、第１貯湯タンク１６内の密度の小さい高温水は矢印ｂのように上昇して第２貯湯タンク１７の上部へ移動する。なお、図８（ｂ）は、第２貯湯タンク１７下部の中温水が第１貯湯タンク１６の下部に移動した後の状態を示す。
【００８５】
本実施形態では、図８（ａ）の温水温度差条件において、第１、第２貯湯タンク１６、１７間での自然対流の循環流量が１．０〜１．３Ｌ／分程度である。これに反し、循環ポンプ２２の循環流量は自然対流の循環流量よりも更に小さい前述の微小流量、具体的には０．６〜１．０Ｌ／分程度となるように設定してある。
【００８６】
この結果、第１、第２貯湯タンク１６、１７が循環ポンプ２２の循環回路に並列接続され、その状態で循環ポンプ２２が作動しても、循環ポンプ２２のポンプ作用よりも自然対流の温水流れの方が上回ることになるので、自然対流による中温水の下方への流れの一部が分岐して循環ポンプ２２に吸入されるだけで、第１貯湯タンク１６内の高温水が循環ポンプ２２に吸入されることはない。
【００８７】
従って、第１、第２貯湯タンク１６、１７の下部に中温水が残存している間は、中温水のみが循環ポンプ２２に選択的に吸入される。この結果、４５℃の中温水と９０℃の高温水とが混合して高圧側熱交換器１３の給水温度が上昇するという現象を回避して、高圧側熱交換器１３の給水温度を低い温度に保って、ヒートポンプユニット１０の高圧側熱交換器１３での高圧冷媒と給水温度との温度差を大きくして、ヒートポンプユニット１０の効率を向上できる。
【００８８】
なお、前述の説明では、図４の給湯使用後の状態から沸き上げ運転を行うときに、第１三方弁２１を第１作動状態に維持して第２貯湯タンク１７の下部接続口１７ｂを遮断した状態で行う旨説明したが、このとき、第１三方弁２１を第２作動状態に切り替えて第１、第２貯湯タンク１６、１７の下部相互間を連通状態にしても第１貯湯タンク１６下部の低温水と第２貯湯タンク１７の高温水の混合は生じない。
【００８９】
すなわち、この場合は、第１、第２貯湯タンク１６、１７の並列回路の形成により図９（ａ）に示すように、第１貯湯タンク１６下部の低温水と第１貯湯タンク１６上部および第２貯湯タンク１７全体の高温水との密度差により第１、第２貯湯タンク１６、１７間で温水の自然対流が発生し、第１貯湯タンク１６下部の密度の大きい低温水が矢印ｃのように下方へ移動して第２貯湯タンク１６の下部に流入する。これに伴って、第２貯湯タンク１７内の密度の小さい高温水は矢印ｄのように上昇して第２貯湯タンク１７の上部へ移動する。なお、図９（ｂ）は、第１貯湯タンク１６下部の低温水が第２貯湯タンク１７の下部に移動した後の状態を示す。
【００９０】
ここで、温水温度差が９０℃−５℃＝８５℃であり、前述の図８（ａ）の場合の温水温度差＝９０℃−４５℃＝４５℃より増大する。そのため、この場合の自然対流の循環流量は、前述の図８（ａ）の場合より大きくなり、１．２〜１．５Ｌ／分程度になる。これに反し、循環ポンプ２２の循環流量はこの自然対流の循環流量よりも小さい前述の微小流量（具体的には０．６〜１．０Ｌ／分程度）である。
【００９１】
従って、この場合も循環ポンプ２２のポンプ作用よりも自然対流の温水流れの方が上回ることになるので、自然対流による低温水の下方への流れの一部が分岐して循環ポンプ２２に吸入されるだけで、第２貯湯タンク１７内の高温水が循環ポンプ２２に吸入されることはない。
【００９２】
つまり、本実施形態では、循環ポンプ２２の循環流量＜自然対流の循環流量という関係を設定することにより、ヒートポンプユニット１０の沸き上げ運転時に第１、第２貯湯タンク１６、１７の下部相互間を連通状態にしても第１貯湯タンク１６下部の低温水と第２貯湯タンク１７の高温水の混合は生じない。
【００９３】
（第２実施形態）
第１実施形態では、第１、第２貯湯タンク１６、１７の下部相互間を連通する連通路１８の遮断手段として、連通路１８と第１給水通路２０を切替開閉する第１三方弁２１を使用しているが、第２実施形態では、図１０に示すように連通路１８の遮断手段として、連通路１８のみを開閉する二方弁タイプの通常の開閉弁２１’を使用し、一方、第１給水通路２０は開閉弁２１’から切り離して第１貯湯タンク１６の下部に直接接続している。
【００９４】
第２実施形態においても、開閉弁２１’により第１実施形態と同じ条件にて連通路１８を遮断すればよい。すなわち、ヒートポンプユニット１０の沸き上げ運転時以外は常に開閉弁２１’を閉弁して連通路１８を遮断することにより、第１実施形態と同様の作用効果を発揮できる。
【００９５】
但し、第１実施形態によると、第１貯湯タンク１６の下部に１個の下部接続口１６ｂを設けるだけでよく、第１貯湯タンク１６下部の水通路構成が簡単になるが、第２実施形態によると、第１貯湯タンク１６の下部に、下部接続口１６ｂの他に第１給水通路２０の接続口１６ｃを追加することになり、第１貯湯タンク１６下部の水通路構成が第１実施形態より複雑となる。
【００９６】
（第３実施形態）
第１、第２実施形態では、第１貯湯タンク１６に対して１個の第２貯湯タンク１７を並列接続しているが、第３実施形態は図１１に示すように第１貯湯タンク１６に対して２個の第２貯湯タンク１７、１７０を並列接続している。
【００９７】
より具体的には、２個の第２貯湯タンク１７、１７０の上部をそれぞれ電磁弁等の電気制御弁からなる開閉弁４０、４１を介してブライン用熱交換器３０の温水通路部３０ａに接続している。
【００９８】
なお、図１１では、第２貯湯タンク１７０に対しても、第１、第２貯湯タンク１６、１７と同様にタンク上下方向の上中下の３箇所に温度センサ４２ａ〜４２ｃが設置してある。
【００９９】
第３実施形態によると、２個の第２貯湯タンク１７、１７０内の温水の温度状態を温度センサ３６ａ〜３６ｃまたは温度センサ４２ａ〜４２ｃの検出温度に基づいて判定し、２この開閉弁４０、４１の開閉を選択することにより、２個の第２貯湯タンク１７、１７０のうち温水温度の高い方の第２貯湯タンクから高温水をブライン用熱交換器３０に循環できる。また、一方の第２貯湯タンク１７０の下部に溜まる中温水を中温水供給通路２５、第２三方弁２６を通して給湯のために使用することができる。
【０１００】
第３実施形態において２個の開閉弁４０、４１を１個の三方弁に置換してもよい。
【０１０１】
（第４実施形態）
第１〜第３実施形態では、いずれも第２貯湯タンク１７、１７０内の高温水を熱源として、ブライン用熱交換器３０を介して床暖房装置３２の放熱作用のみを発揮させるようにしているが、第４実施形態では、図１２に示すように、床暖房装置３２の他に浴室暖房装置３２０の放熱作用も発揮できるようにしている。
【０１０２】
このため、第４実施形態では、床暖房装置３２用の第１ブライン用熱交換器３０と並列に、浴室暖房装置３２０用の第２ブライン用熱交換器３００を設けている。この第２ブライン用熱交換器３００は第１ブライン用熱交換器３０と同一構成でよく、温水通路部３００ａとブライン通路部３００ｂとを有し、温水通路部３００ａ側の温水は電動式の循環ポンプ３１０により循環し、また、ブライン通路部３００ｂのブラインは電動式の循環ポンプ３４０により第２ブライン循環回路３３０を循環する。
【０１０３】
ところで、浴室暖房装置３２０の暖房熱負荷は床暖房装置３２に比較して低いので、浴室暖房装置３２０側のブライン戻り温度および温水戻り温度が床暖房装置３２側より高くなる。具体的一例を述べると、浴室暖房装置３２０側のブライン戻り温度は６０℃、温水戻り温度は６５℃であり、これに対し、床暖房装置３２側のブライン戻り温度は４０℃、温水戻り温度は４５℃である。
【０１０４】
このように、浴室暖房装置３２０側の温水戻り温度＞床暖房装置３２側の温水戻り温度という温度大小関係が生じるので、もし、第２貯湯タンク１７に対する浴室暖房装置３２０側の温水戻り位置と、床暖房装置３２側の温水戻り位置とをともにタンク下部の同一位置に設定すると、浴室暖房装置３２０側の６５℃の戻り温水と、床暖房装置３２側の４５℃の戻り温水が第２貯湯タンク１７の下部で混合され、ヒートポンプユニット１０の高圧側熱交換器１３の給水温度が上昇し、ヒートポンプユニット１０の効率低下を生じる。
【０１０５】
そこで、第４実施形態では、床暖房装置３２側の４５℃の温水戻り位置を第２貯湯タンク１７の下部に設定し、浴室暖房装置３２０側の６５℃の温水戻り位置は、第２貯湯タンク１７の上下方向の中間位置に設定している。
【０１０６】
これにより、床暖房装置３２側の４５℃の戻り温水と、浴室暖房装置３２０側の６５℃の戻り温水を第２貯湯タンク１７の下部と上下方向の中間位置に別々に戻して、２つの温度の異なる戻り温水の混合を防止できる。その結果、４５℃の戻り温水はその温度のままヒートポンプユニット１０の高圧側熱交換器１３に供給して、ヒートポンプユニット１０の効率を向上できる。
【０１０７】
なお、第３、第４実施形態において、第１三方弁２１を第２実施形態と同様に二方弁タイプの通常の開閉弁２１’に置換し、第１給水通路２０は開閉弁２１’から切り離して第１貯湯タンク１６の下部に直接接続してもよいことはもちろんである。
【０１０８】
（第５実施形態）
第４実施形態では１個の第２貯湯タンク１７内の高温水を熱源として、第１、第２ブライン用熱交換器３０、３００を介して床暖房装置３２および浴室暖房装置３２０の放熱作用を発揮させるようにしているが、第５実施形態では、図１３に示すように、２個の第２貯湯タンク１７、１７０を第１貯湯タンク１６に並列に設け、その一方の第２貯湯タンク１７内の高温水を熱源として第１ブライン用熱交換器３０を介して床暖房装置３２を作動させ、他方の第２貯湯タンク１７０内の高温水を熱源として第２ブライン用熱交換器３００を介して浴室暖房装置３２０を作動させる。
【０１０９】
これに伴って、第５実施形態では、第１三方弁２１と同様の第３三方弁２１０を第２貯湯タンク１７と１７０の下部の連通路に追加している。また、中温水供給通路２５には第２貯湯タンク１７と１７０からの中温水供給を切り替える第４三方弁４３を追加している。また、ヒートポンプユニット１０の高圧側熱交換器１３で加熱された高温水が流れる通路にも第５、第６三方弁４４、４５を追加して、第２貯湯タンク１７と１７０の上部への高温水供給の切替、第２貯湯タンク１７と１７０の上部と給湯通路２３との切替等を行うようにしてある。
【図面の簡単な説明】
【図１】本発明の第１実施形態の全体システム図である。
【図２】第１実施形態の電気制御のブロック図である。
【図３】第１実施形態の作動説明図である。
【図４】第１実施形態の作動説明図である。
【図５】第１実施形態の作動説明図である。
【図６】第１実施形態の作動説明図である。
【図７】第１実施形態の作動説明図である。
【図８】第１実施形態の作動説明図である。
【図９】第１実施形態の作動説明図である。
【図１０】第２実施形態の全体システム図である。
【図１１】第３実施形態の全体システム図である。
【図１２】第４実施形態の全体システム図である。
【図１３】第５実施形態の全体システム図である。
【符号の説明】
１０…ヒートポンプユニット、１３…高圧側熱交換器、
１６…第１貯湯タンク、１７、１７０…第２貯湯タンク、１８…連通路、
２０、２８…給水通路、２１…三方弁（遮断手段）、
２１’…開閉弁（遮断手段）、２３…給湯通路、２４…給湯対象機器、
３０、３００…ブライン加熱用熱交換器、３２…床暖房装置（放熱機器）、
３２０…浴室暖房装置（放熱機器）、３３、３３０…ブライン循環回路。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multi-functional heat pump hot water supply device that can supply a brine having a temperature different from that of hot water supply hot water to a heat radiating device such as a floor heating device and can also exhibit a heat dissipation function such as floor heating in addition to a hot water supply function. is there.
[0002]
[Prior art]
Conventionally, in a heat pump hot water supply device, a heat pump unit is provided as a heat source device for hot water, and high temperature water heated by a high pressure side heat exchanger (water-refrigerant heat exchanger) of the heat pump unit is supplied to a hot water supply target device. I have to. By the way, in recent years, in the house, in addition to the hot water supply function, needs for heat radiation devices such as floor heating and bathroom heating are increasing.
[0003]
Therefore, the present inventors are developing a multifunction heat pump type hot water supply apparatus that can exhibit a heat dissipation function such as floor heating in addition to the hot water supply function.
[0004]
In this hot water supply device under development, low temperature hot water from the lower part of the hot water storage tank is introduced into the high pressure side heat exchanger of the heat pump unit and heated to produce high temperature water, and this high temperature water flows into the upper part of the hot water storage tank. And at the time of hot water supply, the high temperature water of the hot water storage tank upper part is supplied to the hot water supply object apparatus.
[0005]
On the other hand, a brine heating heat exchanger (water-water heat exchanger) for exchanging heat between the hot water and the brine from the upper part of the hot water storage tank is provided, and the brine heated by this brine heating heat exchanger is used as a floor heating device, etc. It circulates in the heat radiating device so that the heat radiating effect of the heat radiating device is obtained. Here, the brine is a heat medium that radiates heat using a heat radiating device such as a floor heating device, and specifically, tap water, tap water mixed with antifreeze, or the like can be used.
[0006]
[Problems to be solved by the invention]
By the way, the heat pump unit mainly operates at midnight when the electricity rate is low, and boiles the low temperature water in the hot water storage tank into high temperature water of about 90 ° C., and stores the high temperature water in the hot water storage tank. And if you use a hot water supply target device in the daytime, the hot water at the upper part of the hot water tank is supplied to the hot water supply target device, so only the hot water supply (hot water supply) introduces low-temperature tap water from the water supply pipe to the lower part of the hot water storage tank. Then, low temperature water accumulates at the bottom of the hot water storage tank.
[0007]
Here, the hot water storage tank usually has a vertically long shape having a capacity of about 300 L (in this specification, L represents liter), and hot water flows into the upper part of the tank, and cold water flows into the upper part of the tank. Since the water is supplied, a temperature gradient is formed in which the temperature of the hot water is lower in the lower part of the tank than in the upper part of the tank.
[0008]
On the other hand, the temperature of the hot water after heat exchange with brine in the heat exchanger for heating the brine is maintained at an intermediate temperature of about 45 ° C., although the temperature drops from a high temperature of about 80 ° C. to 90 ° C. before the heat exchange. For this reason, if the intermediate temperature water of about 45 ° C. is returned to the lower part of the hot water storage tank as it is, the stirring of the low temperature water (for example, about 5 ° C. in winter) and the intermediate temperature water from the water supply passage accumulated in the lower part of the hot water storage tank As a result, the boundary layer of the temperature gradient in the hot water storage tank is destroyed, and the temperature of the low-temperature water below the hot water storage tank rises.
[0009]
Therefore, during the next heat pump unit operation (boiling operation), the feed water temperature introduced to the water inlet side of the high pressure side heat exchanger of the heat pump unit rises, and the refrigerant temperature in the high pressure side heat exchanger The temperature difference with the feed water temperature is reduced, and the efficiency (COP) of the heat pump unit is lowered.
[0010]
In view of the above points, an object of the present invention is to suppress a decrease in efficiency due to a rise in feed water temperature of a heat pump unit in a multi-function feed heat pump type hot water apparatus.
[0011]
[Means for Solving the Problems]
  In order to achieve the above object, in the invention described in claim 1, a heat pump unit (10) that heats hot water in the high-pressure side heat exchanger (13) and a hot water outlet side of the high-pressure side heat exchanger (13). At least two hot water storage tanks (16, 17, 170) in which the upper part of the tank is connected in parallel and the lower part of the tank is connected in parallel to the water inlet side of the high pressure side heat exchanger (13), and at least two hot water storage tanks (16, 17). 170), a hot water supply passage (23) for supplying high-temperature water in the upper part of the first hot water storage tank (16) to the hot water supply target device (24) and at least a lower part of the first hot water storage tank (16). Of the passage (20) and the at least two hot water storage tanks (16, 17, 170), a brine heating heat exchanger (30, 30) for exchanging heat between the hot water and brine above the second hot water storage tank (17, 170). 30 ) And a brine circulation circuit (33, 330) for circulating the brine heated by the brine heating heat exchanger (30, 300) to the heat radiating device (32, 320), and a brine heating heat exchanger ( 30, 300) return the intermediate temperature water that has dissipated heat to the lower part of the second hot water storage tank (17, 170), and the lower part of the first hot water storage tank (16) and the second hot water storage tank ( 17 and 170) are provided with blocking means (21 and 21 ') for blocking communication between the hot water storage tanks (16) and (17, 170) in the communication passage (18) communicating with the lower portion of the tank.e,
  The shut-off means (21, 21 ′) is used when hot water in the upper part of the first hot water storage tank (16) is supplied to the hot water supply target device (24) and when the intermediate hot water is returned to the lower part of the second hot water storage tank (17, 170). The communication between the lower parts of both hot water storage tanks (16) (17, 170) is cut off.It is characterized by that.
[0012]
Thereby, while exhibiting the hot water supply function which supplies the hot water of the upper part of the 1st hot water storage tank (16) to hot water supply object apparatus (24) among at least two hot water storage tanks (16, 17, 170) connected in parallel, The brine heated by the high temperature water in the upper part of the second hot water storage tank (17, 170) is circulated to the heat radiating device (32, 320), and the heat radiating function (floor heating function, etc.) is exhibited in the heat radiating device (32, 320). it can.
[0013]
According to the present invention, when hot water in the upper part of the first hot water storage tank (16) is supplied to the hot water supply target device (24), low temperature water (for example, 5 ° C.) is supplied to the lower part of the first hot water storage tank (16), The medium-temperature water (for example, 45 ° C.) whose temperature has decreased due to the heat exchange with the brine returns to the lower part of the second hot water storage tank (17, 170). At that time, the blocking means provided in the communication passage (18) Since the communication between the lower portions of the hot water storage tanks (16), (17, 170) can be blocked by (21, 21 ′), the low temperature water is stored in the lower portion of the first hot water storage tank (16), and the second The storage of the medium temperature water in the lower part of the hot water storage tank (17, 170) can be performed separately.
[0014]
Therefore, at the next boiling operation of the heat pump unit (10), the water whose temperature has been increased by mixing the low temperature water and the medium temperature water is supplied to the water inlet side of the high pressure side heat exchanger (13) of the heat pump unit (10). Therefore, the low-temperature water at the lower part of the first hot water storage tank (16) can be supplied to the high-pressure side heat exchanger (13) in a low-temperature state, and the efficiency (COP) of the heat pump unit can be improved.
[0016]
  Claim2As in the invention described in claim1Specifically, when the hot water in the hot water storage tanks (16) (17, 170) is boiled by the operation of the heat pump unit (10), the water temperature in the lower part of the first hot water storage tank (16) is the second. While the temperature of the water in the lower part of the hot water storage tank (17, 170) is lower than that of the hot water storage tank (17, 170), the communication between the lower parts of the hot water storage tanks (16) (17, 170) is interrupted by the blocking means (21, 21 '). Supplying water in the lower part of (16) to the water inlet side of the high pressure side heat exchanger (13);
  If the water temperature in the lower part of the first hot water storage tank (16) and the water temperature in the lower part of the second hot water storage tank (17, 170) are equal to each other at the time of boiling hot water, the blocking means (21, 21 ′ ) Is switched to the state of communication between the lower parts of both hot water storage tanks (16), (17, 170), and the water in the lower parts of both hot water storage tanks (16), (17, 170) is used as the water in the high pressure side heat exchanger (13). Supply to the inlet side.
[0017]
  Claim3The invention according to claim 1 further comprises a circulation pump (22) for circulating hot water between the hot water storage tanks (16) (17, 170) and the high pressure side heat exchanger (13).
  The hot water circulation flow rate by the circulation pump (22) is made smaller than the hot water circulation flow rate of natural convection due to the hot water temperature difference between the hot water storage tanks (16) (17, 170).
[0018]
  By the way, since the first and second hot water storage tanks (16, 17, 170) are connected in parallel, when the lower portions of both tanks are in communication with each other, natural convection is caused by the difference in hot water temperature between the two tanks. Hot water circulation occurs.
  Claim3Then, paying attention to this point, the hot water circulation flow rate of the hot water circulation pump (22) is made smaller than the hot water circulation flow rate of natural convection between the two tanks. However, natural convection hot water flow will be higher.
[0019]
As a result, the low temperature water is stored in the lower part of the first hot water storage tank (16) and the intermediate temperature water is stored in the lower part of the second hot water storage tank (17, 170). Even if the boiling operation of the unit (10) is performed, the circulation pump (22) can selectively suck only low temperature water and send it to the water inlet side of the high pressure side heat exchanger (13).
[0020]
  Claim3According to this, during the heating operation of the heat pump unit (10), the shut-off means (21, 21 ') can be kept in communication between the lower portions of both tanks. Therefore, it is not necessary to switch between the communication of the cutoff means (21, 21 ') and the cutoff during the boiling operation.
[0021]
  Claim4In the invention described in claim 1, the claims 1 to3In any one of these, the interruption | blocking means is comprised from the three-way valve (21) which switches and opens and closes a 1st water supply path (20) and a communicating path (18),
  The three-way valve (21) shuts off communication between the lower portions of the two hot water storage tanks (16) (17, 170), and communicates the first water supply passage (20) with the lower portion of the first hot water storage tank (16). The operation state is configured to communicate at least between the lower portions of the hot water storage tanks (16) (17, 170) and to switch at least a second operation state for closing the first water supply passage (20). To do.
[0022]
  Thereby, the water supply to the lower part of the 1st hot water storage tank (16) and the communication between the lower parts of both hot water storage tanks can be switched by one three-way valve (21). Therefore, when the first water supply passage (20) is directly connected to the lower part of the first hot water storage tank (16) (the following claims)5), The configuration of the water passage below the first hot water storage tank (16) can be simplified.
[0023]
  Claim5As in the invention described in claim 1,3In any one of the above, the first water supply passage (20) is directly connected to the lower part of the first hot water storage tank (16), and the shut-off means is constituted by an on-off valve (21 ′) for opening and closing the communication passage (18). Also good.
[0024]
  Claim6In the invention described in claim 1, the claims 1 to5In any one of these, it is characterized by comprising a medium-temperature water supply passage (25) for supplying medium-temperature water below the second hot water storage tank (17, 170) to the hot-water supply passage (23).
[0025]
Thereby, the intermediate temperature water which accumulates in the lower part of the second hot water storage tank (17, 170) can be effectively used for hot water supply.
[0026]
As a result, it is possible to save the use of high-temperature water above both hot water storage tanks during hot water supply, and to reduce the remaining amount of medium-temperature water until the next boiling operation of the heat pump unit (10). The amount of low-temperature water stored in the lower part of the hot water storage tank increases as the remaining amount of medium-temperature water decreases. Since the probability increases, it is even more advantageous for improving the efficiency (COP) of the heat pump unit.
[0027]
  Claim7In the invention described in the above, the heat pump unit (10) for heating the hot water in the high-pressure side heat exchanger (13) and the tank upper part are connected in parallel to the hot water outlet side of the high-pressure side heat exchanger (13). Of the at least two hot water storage tanks (16, 17, 170) whose lower tank is connected in parallel to the water inlet side of the exchanger (13) and the first hot water storage tank among the at least two hot water storage tanks (16, 17, 170). (16) A hot water supply passage (23) for supplying high temperature water in the upper part to the hot water supply target device (24), a first water supply passage (20) for supplying water to at least the lower part of the first hot water storage tank (16), and at least two hot water storages Among the tanks (16, 17, 170), the brine heating heat exchanger (30, 300) and the brine heating heat exchanger for exchanging heat between the hot water and the brine at the upper part of the second hot water storage tank (17, 170). ( And a brine circulation circuit (33, 330) that circulates the brine heated in 0, 300) to the heat dissipation device (32, 320), and dissipates heat by passing through the brine heating heat exchanger (30, 300). The medium hot water is supplied to the lower part of the second hot water storage tank (17, 170), and the intermediate hot water below the second hot water storage tank (17, 170) is supplied to the hot water supply passage (23). A passage (25) is provided.
[0028]
Thus, as in the first aspect, the hot water supply function of supplying the hot water in the upper part of the first hot water storage tank (16) to the hot water supply target device (24) is exhibited and the high temperature in the upper part of the second hot water storage tank (17, 170). The brine heated by water can be circulated to the heat radiating device (32, 320) to exhibit a heat radiating function (floor heating function or the like) in the heat radiating device (32, 320).
[0029]
  And claims7According to the present invention, the hot water stored in the lower part of the second hot water storage tank (17, 170) can be used effectively for hot water supply. The remaining amount of medium temperature water can be reduced by the next boiling operation of 10).
  Claimed by reduction of the remaining amount of medium temperature water6In the same manner as in the above, since the probability of boiling of the medium-temperature water decreases during the next boiling operation and the probability of boiling of the low-temperature water increases, the efficiency (COP) of the heat pump unit can be improved.
[0030]
  Claim8In the invention described in claim6 or 7, A second water supply passage (28) for supplying water to the hot water supply passage (23), a water supply from the second water supply passage (28) to the hot water supply passage (23), and a medium temperature water supply passage ( 25) and a switching means (26) for switching the medium temperature water supply.
[0031]
Thereby, the hot water supply passage (23) can be switched between the low temperature water supply from the second water supply passage (28) and the medium temperature water from the intermediate hot water supply passage (25) and supplied to the hot water supply target device (24). Therefore, by adjusting the mixing ratio of the high temperature water from the upper part of the first hot water storage tank (16) and the low temperature water supply from the second water supply passage (28) or the medium temperature water from the intermediate temperature water supply passage (25), The hot water supply temperature to the device (24) can be adjusted.
[0032]
  Claim9In the invention described in claim 1, the claims 1 to8In any one of the above, a plurality of brine heating heat exchangers (30, 300) are connected in parallel to the second hot water storage tank (17, 170), and a plurality of brine heating heat exchangers ( 30 and 300) are provided with a plurality of brine circulation circuits (33 and 330), and a plurality of heat dissipation devices (32 and 320) respectively corresponding to the plurality of brine circulation circuits (33 and 330) are provided as heat dissipation devices. ), And return the medium-temperature water having the lower temperature out of the medium-temperature water that has passed through the plurality of brine heating heat exchangers (30, 300) to the lower part of the second hot water storage tank (17, 170). Of the hot water, the medium-temperature water having the higher temperature is returned to a position higher than the return position of the medium-temperature water having the lower temperature relative to the second hot water storage tank (17, 170).
[0033]
Thereby, when returning the warm water having different temperatures respectively passing through the plurality of brine heating heat exchangers (30, 300) to the second hot water storage tank (17, 170), the second hot water storage tank (17, 170). The middle temperature water having the lower temperature can be stored in the lower portion of the tank, and the medium temperature water having the higher temperature can be stored in the middle portion of the second hot water storage tank (17, 170). Accordingly, it is possible to prevent the intermediate temperature water having a low temperature and the intermediate temperature water having a high temperature from being mixed in the second hot water storage tank (17, 170), so that the temperature of the intermediate temperature water having the lower temperature can be prevented from rising. COP) is advantageous in terms of improvement.
[0034]
  Claim10As in the invention described in claim9, One of the plurality of heat dissipating devices is specifically a floor heating device (32), and the other one is specifically a bathroom heating device (320).
[0035]
Thereby, the floor heating function and the bathroom heating function can be exhibited in addition to the hot water supply function.
[0036]
  Claim11As in the invention described in claim 1,10In any one of the above, if the heat pump unit (10) is configured with a supercritical refrigeration cycle in which the high-pressure side pressure is equal to or higher than the critical pressure of the refrigerant, the efficiency (COP) of the supercritical refrigeration cycle is effectively improved. it can.
[0037]
In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.
[0038]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
In the first embodiment, the present invention is applied to a general-purpose multifunctional heat pump hot water supply device. FIG. 1 is an overall configuration diagram of the hot water supply device, and the configuration of the hot water supply device forms a hot water heat source. The heat pump unit 10 is roughly divided into a hot water storage tank unit 11 that stores high-temperature water heated by the heat pump unit 10.
[0039]
The heat pump unit 10 uses CO as a refrigerant.₂And a supercritical refrigeration cycle in which the high-pressure side pressure is equal to or higher than the critical pressure of the refrigerant. The heat pump unit 10 has an electric compressor 12 capable of controlling the number of revolutions, and causes the high-pressure refrigerant compressed by the electric compressor 12 to flow into the high-pressure side heat exchanger 13 for heating. The high-pressure heat exchanger 13 constitutes a water-refrigerant heat exchanger that heats water by exchanging heat between the high-pressure refrigerant and water. The high-pressure refrigerant after heat dissipation that has passed through the high-pressure side heat exchanger 13 is then decompressed to a low-pressure state by the decompression device 14.
[0040]
This low-pressure refrigerant flows into the evaporator 15 constituting the low-pressure side (heat absorption) heat exchanger, absorbs heat from the atmosphere and evaporates in the evaporator 15, and then the refrigerant is sucked into the electric compressor 12 and compressed again. The The heat pump unit 10 constitutes an electric heat source device that is operated mainly at night using night electricity that is inexpensive and heats hot water.
[0041]
The hot water storage tank unit 11 has a vertically long first hot water storage tank 16 and a second hot water storage tank 17. The first and second hot water storage tanks 16 and 17 have the same capacity in this example, and have a capacity of about 150 L (liter), for example. The first and second hot water storage tanks 16 and 17 are connected in parallel in the hot water circulation circuit of the high-pressure side heat exchanger 13 of the heat pump unit 10.
[0042]
That is, the upper connection ports 16 a and 17 a provided at the uppermost portions of the first and second hot water storage tanks 16 and 17 are connected in parallel to the hot water outlet side of the high pressure side heat exchanger 13. The lower connection port 16b provided in the lower part and the lower connection port 17b provided in the lowermost part of the second hot water storage tank 17 are connected in parallel to the water inlet side (water supply side) of the high-pressure side heat exchanger 13.
[0043]
More specifically, an intermediate portion of the communication passage 18 that communicates the lower connection port 16b of the first hot water storage tank 16 and the lower connection port 17b of the second hot water storage tank 17 is connected to the water of the high pressure side heat exchanger 13 by the heat pump inlet passage 19. In addition to communicating with the inlet side, tap water is supplied to the lower connection port 16b of the first hot water storage tank 16 to a portion of the communication passage 18 closer to the second hot water storage tank 17 than the branching position of the heat pump inlet passage 19. The first water supply passage 20 is joined, and a first three-way valve 21 is provided at this joining point.
[0044]
The first three-way valve 21 constitutes a shut-off means of the present invention, and is an electric control valve that drives a valve element by an actuator such as a motor. The first three-way valve 21 of this example can select the following three operating states by switching the valve element position.
[0045]
That is, the first three-way valve 21 blocks the communication between the lower portions of the first and second hot water storage tanks 16, 17 and connects the first water supply passage 20 to the lower connection port 16 b of the first hot water storage tank 16. Between the operating state, the second operating state in which the lower portions of the first and second hot water storage tanks 16, 17 communicate with each other and close the first water supply passage 20, and the lower portions of the first and second hot water storage tanks 16, 17 Is switched to a third operating state in which the first water supply passage 20 is communicated with the lower connection port 17b of the second hot water storage tank 17.
[0046]
An electric circulation pump 22 is installed in the heat pump inlet passage 19, and hot water circulation between the first and second hot water storage tanks 16 and 17 and the high-pressure side heat exchanger 13 of the heat pump unit 10 is performed by the operation of the circulation pump 22. Is supposed to do. Here, in order to heat the hot water to a high temperature around 90 ° C. in the high pressure side heat exchanger 13 of the heat pump unit 10, it is necessary to reduce the circulating flow rate of the hot water. The minute flow rate is set to about 0.6 to 1.0 L / min.
[0047]
On the other hand, a hot water outlet 16d is provided at the uppermost part of the first hot water storage tank 16, and a hot water supply passage 23 is connected to the hot water outlet 16d, and the hot water supply passage 23 is connected to a hot water supply target device 24 such as a kitchen, a washroom, and a bath. It is designed to supply hot water.
[0048]
A medium temperature water supply passage 25 for supplying medium temperature water, which will be described later, accumulated in the lower part of the second hot water storage tank 17 is joined to the hot water supply path 23. More specifically, a second three-way valve 26 composed of an electric control valve such as an electromagnetic valve is provided in the middle hot water supply passage 25, and a passage on the downstream side of the second three-way valve 26 in the middle hot water supply passage 25 is provided. It joins in the middle of the hot water supply passage 23. And the temperature control valve 27 is arrange | positioned at this junction.
[0049]
A second water supply passage 28 is connected to the second three-way valve 26, and the medium temperature water supply passage 25 and the tap water from the second water supply passage 28 are switched and introduced to the temperature adjustment valve 27. The temperature adjustment valve 27 adjusts the hot water supply temperature by adjusting the mixing ratio of the high temperature water from the hot water supply passage 23 and the medium temperature water of the intermediate temperature water supply passage 25 or the low temperature tap water from the second water supply passage 28.
[0050]
The temperature adjustment valve 27 of this example is configured such that the valve body for adjusting the mixing ratio is driven by an actuator such as a motor, and a temperature at which the temperature of the hot water supply water is detected in the downstream passage of the temperature adjustment valve 27. A sensor 29 is disposed, and the valve body position is automatically adjusted so that the temperature of the hot water supply hot water detected by the temperature sensor 29 becomes the target temperature set by the user. Thereby, the temperature of the hot water supply hot water is maintained at the target temperature.
[0051]
On the other hand, a brine heating heat exchanger 30 is connected to the second hot water storage tank 17. In the heat exchanger 30 for heating the brine, the hot water passage portion 30a into which the high temperature water flows from the upper part of the second hot water storage tank 17 and the brine heated by exchanging heat with the high temperature water in the hot water passage portion 30a pass. And a brine passage 30b. The outlet of the hot water passage 30a is connected to the lower part of the second hot water storage tank 17, and the medium hot water (for example, hot water of about 45 ° C.) whose temperature has been lowered by heat exchange with brine in the hot water passage 30a is the second hot water storage tank. Return to the bottom of 17. Hot water circulates between the second hot water storage tank 17 and the hot water passage portion 30a by the electric circulation pump 31 provided on the outlet side of the hot water passage portion 30a.
[0052]
Further, the brine passage 30b is connected to a floor heating device 32 that constitutes a heat radiating device for the brine to constitute a brine circulation circuit 33. In this brine circulation circuit 33, an electric circulation pump 34 is provided on the inlet side of the brine passage 30b, and the brine heated in the brine passage 30b by this circulation pump 34 is circulated to the floor heating device 32. Here, the brine is a heat medium that is heated in the heat exchanger 30 and dissipates heat in the floor heating device 32. Specifically, tap water, tap water mixed with antifreeze, or the like can be used.
[0053]
In the vertically long first and second hot water storage tanks 16 and 17, a temperature gradient of hot water is formed in the vertical direction of the tank. Therefore, in order to be able to determine the gradient of the hot water temperature in the vertical direction in the first and second hot water storage tanks 16 and 17, the first and second hot water storage tanks 16 and 17 have different heights in the vertical direction of the tank. A plurality of temperature sensors 35a, 35b, 35c, 36a, 36b, 36c are provided to detect hot water temperatures at different heights in the tank vertical direction. In the illustrated example, the first and second hot water storage tanks 16 and 17 are provided with temperature sensors 35a to 35c and 36a to 36c at three locations, upper, middle, and lower, respectively.
[0054]
Moreover, the temperature sensor 37 which detects the temperature of the tap water supplied to the 1st, 2nd water supply path 20 and 28 is provided. In FIG. 1, a temperature sensor 37 is illustrated at a site on the second water supply passage 28 side.
[0055]
Next, the schematic configuration of the electric control according to the first embodiment will be described with reference to FIG. 2. The electronic control unit 38 is composed of a microcomputer and its peripheral circuits, and is based on a predetermined program based on a preset program. Arithmetic processing is performed to control the operation of various devices of the hot water supply apparatus.
[0056]
Sensor detection signals such as temperature sensors 29, 35 a to 35 c, 36 a to 36 c, and 37 are input to the input side of the electronic control device 38. In addition, operation signals of various operation switches (not shown) of the hot water supply device operation panel 39 are input to the input side of the electronic control device 38. As an operation switch of the hot water supply device operation panel 39, a temperature setting switch for setting the target temperature of the hot water supply hot water is provided.
[0057]
On the other hand, devices such as the electric compressor 12 of the heat pump unit 11, the circulation pumps 22, 31, and 34, the first and second three-way valves 21 and 26, and the temperature control valve 27 are connected to the output side of the electronic control unit 38. The operation of these devices is controlled by the output of the electronic control unit 38.
[0058]
Next, the operation of the first embodiment will be described. The heat pump unit 10 is operated mainly using nighttime (midnight) power, and the water flowing into the high-pressure side heat exchanger 13 by the circulation pump 22 is exchanged with the high-pressure side heat exchanger. Heat in a vessel 13 and boil up to high temperature water of about 90 ° C.
[0059]
FIG. 3 shows a state where the heat pump unit 10 is heated up at night to complete the heating in which high temperature water of about 90 ° C. is filled up to the lower portions of the first and second hot water storage tanks 16 and 17. This boiling completion state can be determined based on the temperature detected by the temperature sensors 35c and 36c below the first and second hot water storage tanks 16 and 17. That is, the completion of boiling can be determined by determining by the electronic control unit 38 that the temperature detected by the temperature sensors 35c and 36c has increased to a predetermined temperature.
[0060]
When the electronic control unit 38 determines that the boiling is completed, the electric compressor 12 is stopped and the operation of the heat pump unit 11 is stopped. When it is determined that the boiling has been completed, the electronic control unit 38 sets the first three-way valve 21 to the first operating state. That is, the first three-way valve 21 shuts off the passage on the lower connection port 17 b side of the second hot water storage tank 17 and communicates the first water supply passage 20 to the lower connection port 16 b side of the first hot water storage tank 16. It becomes. The first three-way valve 21 maintains this first operating state until the next boiling operation.
[0061]
FIG. 4 shows a state after hot water is supplied to the hot water supply target device 24 from the state of FIG. 3 and about 90 ° C. high-temperature water in the first hot water storage tank 16 is used about half of the tank capacity (75 L). Since the first three-way valve 21 maintains the first operating state during the hot water supply, when the hot water supply target device 24 discharges hot water, the low-temperature (5 ° C. in this example) tap water in the first water supply passage 20 is the first. It passes through the three-way valve 21 and the communication passage 18 and flows into the first hot water storage tank 16 from the lower connection port 16 b of the first hot water storage tank 16.
[0062]
On the other hand, since the lower connection port 17 b of the second hot water storage tank 17 is closed by the first three-way valve 21, the low temperature water in the first water supply passage 20 does not flow into the second hot water storage tank 17. Further, since the water pressure of the first water supply passage 20 is not applied to the second hot water storage tank 17, the high temperature water in the second hot water storage tank 17 is not used for hot water supply.
[0063]
Next, temperature adjustment of hot water supply hot water will be described. The second three-way valve 26 provided in the middle of the intermediate hot water supply passage 25 from the second hot water storage tank 17 is set by a temperature setting switch of the hot water supply device operation panel 39. Passage switching based on the target temperature To of hot water supply hot water, the hot water temperature T36c detected by the temperature sensor 36c below the second hot water storage tank 17, and the water supply temperature T37 detected by the temperature sensor 37 of the second water supply passage 28 Perform the operation. In particular,
(1) When the relationship of target temperature To <warm water temperature T36c below the second hot water storage tank is established, the electronic control device 38 determines this temperature relationship, and the second three-way valve 26 is activated by the output signal of the electronic control device 38. The intermediate temperature water supply passage 25 is shut off, and the second water supply passage 28 is brought into communication with the passage on the temperature adjustment valve 27 side.
[0064]
In FIG. 4, the high temperature water is filled up to the lower part of the second hot water storage tank 17, so the temperature relationship of the above (1) is established. Therefore, the low temperature water from the second water supply passage 28 is supplied to the temperature adjustment valve 27. Therefore, in the state of FIG. 4, the temperature adjustment valve 27 adjusts the mixing ratio of the low temperature water from the second water supply passage 28 and the high temperature water from the upper part of the first hot water storage tank 16 to adjust the temperature of the hot water supply hot water to the user. To the target temperature To set.
[0065]
(2) When the relationship of target temperature To> warm water temperature T36c in the lower part of the second hot water storage tank> feed water temperature T37 is established, the hot water temperature T36c is lower than the target temperature To and higher than the feed water temperature T37. Therefore, when the electronic control device 38 determines this temperature relationship, the second three-way valve 26 shuts off the second water supply passage 28 and puts the intermediate temperature water supply passage 25 into a communication state by an output signal of the electronic control device 38. Therefore, the intermediate temperature water below the second hot water storage tank is supplied to the temperature adjustment valve 27 through the intermediate temperature water supply passage 25.
[0066]
By the way, when the boiling operation is performed from the state after using the hot water supply in FIG. 4, since the inside of the second hot water storage tank 17 is filled with high temperature water of about 90 ° C., the low temperature water below the first hot water storage tank 16 is boiled. Just raise it. Therefore, at this time, the heating operation is performed while the first three-way valve 21 is maintained in the above-described first operating state by the output signal of the electronic control unit 38 (while the lower connection port 17b of the second hot water storage tank 17 is shut off). Do.
[0067]
Next, FIG. 5 shows a state after further using the floor heating device 32 from the state after using the hot water supply of FIG. When the usage state of the floor heating device 32 is set, the circulation pumps 31 and 34 are activated by the output signal of the electronic control device 38. The hot water in the upper part of the second hot water storage tank 17 flows into the hot water passage 30a of the brine heating heat exchanger 30 by the operation of the circulation pump 31, and the brine in the brine circulation circuit 33 is heated by the operation of the circulation pump 34. It flows into the brine passage 30b of the heat exchanger 30 for use.
[0068]
As a result, the high-temperature water and brine exchange heat in the heat exchanger 30, and the brine rises to a temperature of, for example, about 60 ° C. and flows into the floor heating device 32. To do. The temperature of the brine after the heat radiation is lowered to, for example, about 40 ° C., and returns to the brine passage 30b of the brine heating heat exchanger 30. Further, the high-temperature water from the second hot water storage tank 17 dissipates heat in the brine heating heat exchanger 30, and the temperature drops to, for example, about 45 ° C. and returns to the lower part of the second hot water storage tank 17.
[0069]
At this time, the first three-way valve 21 maintains the above-described first operating state in which the lower connection port 17b of the second hot water storage tank 17 is shut off, so that the return hot water from the brine heating heat exchanger 30 is the first. There is no return to the lower part of the hot water storage tank 16.
[0070]
As described above, as the floor heating device 32 is used, the return hot water from the brine heating heat exchanger 30, that is, the intermediate temperature water of about 45 ° C. gradually accumulates in the lower part of the second hot water storage tank 17. FIG. 5 shows a state where intermediate temperature water of about half of the tank capacity is accumulated in the lower part of the second hot water storage tank 17.
[0071]
Next, FIG. 6 shows a state in which hot water is supplied to the hot water supply target device 24 again from the state after using the floor heating apparatus of FIG. In the state after using the floor heating apparatus of FIG. 5, the medium-temperature water has accumulated in the lower part of the second hot water storage tank 17, so that the temperature relationship of the above-mentioned (2), that is,
The relationship of target temperature To> warm water temperature T36c below the second hot water storage tank> feed water temperature T37 is established.
[0072]
For this reason, the second three-way valve 26 is switched to a state in which the second water supply passage 28 is shut off and the intermediate temperature water supply passage 25 is brought into a communication state by the output signal of the electronic control device 38. At this time, the first three-way valve 21 maintains the above-described first operating state in which the lower connection port 17b of the second hot water storage tank 17 is shut off. Therefore, when hot water is supplied to the hot water supply target device 24, the medium temperature water below the second hot water storage tank is supplied to the temperature adjustment valve 27 through the medium temperature water supply passage 25.
[0073]
Thus, the temperature adjustment valve 27 adjusts the mixing ratio of the medium temperature water from the medium temperature water supply passage 25 and the high temperature water from the first hot water storage tank 16 to adjust the hot water supply hot water to the target temperature To. At this time, since the intermediate temperature water below the second hot water storage tank 17 is used for hot water supply, the amount of high temperature water supplied from the upper part of the first hot water storage tank 16 to the hot water supply passage 23 is saved, and at the same time, The amount of hot water can be actively reduced.
[0074]
Then, by using the middle temperature water at the lower part of the second hot water storage tank 17 for hot water supply, the high temperature water at the upper part of the first hot water storage tank 16 flows into the upper part of the second hot water storage tank 17, and the lower part of the first hot water storage tank 16 Low-temperature tap water passes through the first three-way valve 21 from the one water supply passage 20 and flows in from the lower connection port 16c. Therefore, the ratio of the low temperature water in the lower part of the first hot water storage tank 16 increases. FIG. 6 shows a state in which the ratio of the low temperature water at the lower part of the first hot water storage tank 16 is increased and the ratio of the high temperature water at the upper part of the second hot water storage tank 17 is increased.
[0075]
When the hot water supply to the hot water supply target device 24 is further continued from the state of FIG. 6, the low temperature water is filled to the upper part of the first hot water storage tank 16 as shown in FIG. The hot water may be used up for hot water supply, and high temperature water may fill up to the lower part of the second hot water storage tank 17 or a small amount of medium temperature water may remain in the lower part of the second hot water storage tank 17.
[0076]
As described above, when the electronic control unit 38 determines that the low-temperature water is filled up to the upper part of the first hot water storage tank 16 based on the temperature detected by the temperature sensor 35a at the upper part of the tank, the first signal is output from the output signal of the electronic control unit 38. The three-way valve 21 is switched to the aforementioned third operating state. That is, the first three-way valve 21 blocks communication between the lower portions of the first and second hot water storage tanks 16 and 17, and connects the first water supply passage 20 to the lower connection port 17 b of the second hot water storage tank 17.
[0077]
Thereby, since the water pressure of the 1st water supply path 20 is added to the lower part of the 2nd hot water storage tank 17, when hot water supply to the hot water supply object device 24 is performed, hot water is pushed out from the upper part of the second hot water storage tank 17 by the water pressure, It is supplied to the hot water supply passage 23 through the upper part of the first hot water storage tank 16.
[0078]
Simultaneously with the switching operation of the first three-way valve 21, the second three-way valve 26 is switched to a state in which the second water supply passage 28 side is opened and the intermediate hot water supply passage 25 side is closed by the output signal of the electronic control device 38. Accordingly, the temperature adjustment valve 27 adjusts the mixing ratio of the low temperature water from the second water supply passage 28 and the high temperature water from the second hot water storage tank 17 to adjust the hot water supply hot water to the target temperature To.
[0079]
As described above, hot water can be supplied to the hot water supply target device 24 by effectively using the high-temperature water in the second hot water storage tank 17.
[0080]
Next, the case where the boiling operation is performed from the state after reuse of the hot water supply in FIG. 6 described above will be described. In this case, the hot water temperature T35c below the first hot water storage tank 16 <the hot water temperature T36c below the second hot water storage tank 17. Is determined by the electronic control unit 38, and the first three-way valve 21 is maintained in the first operating state by the output signal of the electronic control unit 38. At this time, the lower connection port of the second hot water storage tank 17 is maintained. The state which interrupted | blocked 17b is maintained.
[0081]
Therefore, the low-temperature water at the lower part of the first hot water storage tank 16 flows into the high-pressure side heat exchanger 13 of the heat pump unit 10 and is heated by the operation of the circulation pump 22, and the high-temperature water after this heating enters the upper part of the first hot water storage tank 16. Inflow. Then, as shown in FIG. 8A, when the hot water is filled to the lower part of the first hot water storage tank 16, the electronic control unit 38 determines this based on the temperature detected by the lower temperature sensor 35c, and the first three-way The valve 21 is switched to the second operating state described above, and the lower connection port 17 b of the second hot water storage tank 17 is communicated with the heat pump inlet passage 19 via the communication passage 18.
[0082]
As a result, the first and second hot water storage tanks 16 and 17 are connected in parallel to the circulation circuit of the circulation pump 22, but only the medium temperature water (45 ° C.) below the second hot water storage tank 17 is selective for the following reason. Therefore, the phenomenon that the feed water temperature of the high-pressure side heat exchanger 13 rises due to mixing of the medium temperature water of 45 ° C. and the high temperature water of 90 ° C. does not occur.
[0083]
In the state shown in FIG. 8A, a first hot water storage tank 16 filled with high-temperature water and a second hot water storage tank 17 in which medium-temperature water remains in the lower part of the tank are connected in parallel via the first three-way valve 21. The hot water between the first and second hot water storage tanks 16 and 17 due to the difference in density between the middle temperature water below the second hot water storage tank 17 and the high temperature water in the upper part of the second hot water storage tank 17 and the entire first hot water storage tank 16. Natural convection occurs.
[0084]
That is, the medium-temperature water having a high density moves downward as indicated by an arrow a and flows into the lower portion of the first hot water storage tank 16. Along with this, the hot water having a low density in the first hot water storage tank 16 rises as indicated by an arrow b and moves to the upper part of the second hot water storage tank 17. FIG. 8B shows a state after the medium temperature water below the second hot water storage tank 17 has moved to the lower part of the first hot water storage tank 16.
[0085]
In the present embodiment, the natural convection circulation flow rate between the first and second hot water storage tanks 16 and 17 is about 1.0 to 1.3 L / min under the hot water temperature difference condition of FIG. On the other hand, the circulation flow rate of the circulation pump 22 is set to be the above-mentioned minute flow rate, which is smaller than the natural convection circulation flow rate, specifically about 0.6 to 1.0 L / min.
[0086]
As a result, even if the first and second hot water storage tanks 16 and 17 are connected in parallel to the circulation circuit of the circulation pump 22 and the circulation pump 22 is operated in this state, the hot water flow is more natural convection than the pump action of the circulation pump 22. Therefore, only a part of the downward flow of the medium-temperature water due to natural convection branches and is sucked into the circulation pump 22, and the high-temperature water in the first hot water storage tank 16 is supplied to the circulation pump 22. It is not inhaled.
[0087]
Therefore, only the intermediate temperature water is selectively sucked into the circulation pump 22 while the intermediate temperature water remains in the lower portions of the first and second hot water storage tanks 16 and 17. As a result, it avoids the phenomenon that the medium temperature water of 45 ° C. and the high temperature water of 90 ° C. are mixed to increase the feed water temperature of the high pressure side heat exchanger 13, and the feed water temperature of the high pressure side heat exchanger 13 is lowered. Thus, the temperature difference between the high-pressure refrigerant and the feed water temperature in the high-pressure side heat exchanger 13 of the heat pump unit 10 can be increased to improve the efficiency of the heat pump unit 10.
[0088]
In the above description, when the boiling operation is performed from the state after using the hot water supply in FIG. 4, the first three-way valve 21 is maintained in the first operating state and the lower connection port 17 b of the second hot water storage tank 17 is shut off. However, at this time, the first three-way valve 21 is switched to the second operation state so that the lower portions of the first and second hot water storage tanks 16 and 17 are in communication with each other. Mixing of the low temperature water in the lower portion and the high temperature water in the second hot water storage tank 17 does not occur.
[0089]
That is, in this case, as shown in FIG. 9A, the parallel circuit of the first and second hot water storage tanks 16 and 17 forms the low temperature water at the lower part of the first hot water storage tank 16 and the upper part of the first hot water storage tank 16 and the first hot water storage tank 16. The natural convection of the hot water is generated between the first and second hot water storage tanks 16 and 17 due to the density difference with the high temperature water of the entire two hot water storage tanks 17, and the low temperature water having a high density at the lower part of the first hot water storage tank 16 is indicated by an arrow c. It moves downward and flows into the lower part of the second hot water storage tank 16. Along with this, the hot water having a low density in the second hot water storage tank 17 rises as indicated by an arrow d and moves to the upper part of the second hot water storage tank 17. FIG. 9B shows a state after the low temperature water in the lower part of the first hot water storage tank 16 has moved to the lower part of the second hot water storage tank 17.
[0090]
Here, the hot water temperature difference is 90 ° C.−5 ° C. = 85 ° C., which is larger than the hot water temperature difference = 90 ° C.−45 ° C. = 45 ° C. in the case of FIG. Therefore, the circulation flow rate of natural convection in this case is larger than that in the case of FIG. 8A described above, and is about 1.2 to 1.5 L / min. On the contrary, the circulation flow rate of the circulation pump 22 is the above-described minute flow rate (specifically, about 0.6 to 1.0 L / min) smaller than the circulation flow rate of natural convection.
[0091]
Accordingly, in this case as well, the natural convection hot water flow exceeds the pumping action of the circulation pump 22, so a part of the flow of the low-temperature water below the natural convection branches off and is sucked into the circulation pump 22. Therefore, the high-temperature water in the second hot water storage tank 17 is not sucked into the circulation pump 22.
[0092]
That is, in the present embodiment, the relationship between the circulation flow rate of the circulation pump 22 <the circulation flow rate of natural convection is set, so that the lower portions of the first and second hot water storage tanks 16 and 17 are connected to each other during the heating operation of the heat pump unit 10. Even in the communication state, mixing of the low temperature water below the first hot water storage tank 16 and the high temperature water of the second hot water storage tank 17 does not occur.
[0093]
(Second Embodiment)
In the first embodiment, the first three-way valve 21 that switches between the communication passage 18 and the first water supply passage 20 is used as a blocking means for the communication passage 18 that communicates between the lower portions of the first and second hot water storage tanks 16 and 17. Although used, in the second embodiment, as shown in FIG. 10, a two-way valve type normal on-off valve 21 ′ that opens and closes only the communication path 18 is used as a blocking means for the communication path 18, while The first water supply passage 20 is disconnected from the on-off valve 21 ′ and directly connected to the lower part of the first hot water storage tank 16.
[0094]
Also in the second embodiment, the communication path 18 may be blocked by the on-off valve 21 'under the same conditions as in the first embodiment. In other words, the operation and effect similar to those of the first embodiment can be exhibited by always closing the on-off valve 21 ′ and closing the communication path 18 except during the heating operation of the heat pump unit 10.
[0095]
However, according to the first embodiment, it is only necessary to provide one lower connection port 16b at the lower part of the first hot water storage tank 16, and the water passage configuration at the lower part of the first hot water storage tank 16 is simplified. According to the first embodiment, the connection port 16c of the first water supply passage 20 is added to the lower portion of the first hot water storage tank 16 in addition to the lower connection port 16b, and the water passage configuration below the first hot water storage tank 16 is the first embodiment. More complicated.
[0096]
(Third embodiment)
In the first and second embodiments, one second hot water storage tank 17 is connected in parallel to the first hot water storage tank 16, but in the third embodiment, as shown in FIG. On the other hand, two second hot water storage tanks 17 and 170 are connected in parallel.
[0097]
More specifically, the upper portions of the two second hot water storage tanks 17 and 170 are connected to the hot water passage portion 30a of the brine heat exchanger 30 via on-off valves 40 and 41, each of which is an electric control valve such as an electromagnetic valve. is doing.
[0098]
In FIG. 11, the temperature sensors 42 a to 42 c are also installed in the upper, lower, and upper three locations of the second hot water storage tank 170 in the same manner as the first and second hot water storage tanks 16 and 17. .
[0099]
According to the third embodiment, the temperature state of the hot water in the two second hot water storage tanks 17 and 170 is determined based on the temperature detected by the temperature sensors 36a to 36c or the temperature sensors 42a to 42c. By selecting the opening and closing of 41, high temperature water can be circulated to the brine heat exchanger 30 from the second hot water storage tank having the higher hot water temperature of the two second hot water storage tanks 17 and 170. Further, the medium-temperature water accumulated in the lower portion of one second hot water storage tank 170 can be used for hot water supply through the medium-temperature water supply passage 25 and the second three-way valve 26.
[0100]
In the third embodiment, the two on-off valves 40 and 41 may be replaced with one three-way valve.
[0101]
(Fourth embodiment)
In the first to third embodiments, the high-temperature water in the second hot water storage tanks 17 and 170 is used as a heat source, and only the heat radiation action of the floor heating device 32 is exhibited through the brine heat exchanger 30. However, in 4th Embodiment, as shown in FIG. 12, the heat dissipation effect | action of the bathroom heating apparatus 320 other than the floor heating apparatus 32 can also be exhibited.
[0102]
For this reason, in the fourth embodiment, the second brine heat exchanger 300 for the bathroom heating device 320 is provided in parallel with the first brine heat exchanger 30 for the floor heating device 32. The second brine heat exchanger 300 may have the same configuration as the first brine heat exchanger 30, and has a hot water passage 300a and a brine passage 300b, and the hot water on the hot water passage 300a side is electrically circulated. The brine in the brine passage section 300b circulates in the second brine circulation circuit 330 by the electric circulation pump 340.
[0103]
By the way, since the heating heat load of the bathroom heating device 320 is lower than that of the floor heating device 32, the brine return temperature and the hot water return temperature on the bathroom heating device 320 side are higher than those on the floor heating device 32 side. As a specific example, the brine return temperature on the bathroom heating device 320 side is 60 ° C. and the hot water return temperature is 65 ° C., whereas the brine return temperature on the floor heating device 32 side is 40 ° C. and the hot water return temperature is 45 ° C.
[0104]
Thus, since the temperature magnitude relationship of hot water return temperature on the side of the bathroom heating device 320> warm water return temperature on the side of the floor heating device 32 occurs, if the hot water return position on the side of the bathroom heating device 320 with respect to the second hot water storage tank 17, If both the warm water return position on the floor heating device 32 side is set at the same position at the bottom of the tank, the 65 ° C. return warm water on the bathroom heating device 320 side and the 45 ° C. return warm water on the floor heating device 32 side are the second hot water storage tank. 17, the feed water temperature of the high-pressure side heat exchanger 13 of the heat pump unit 10 rises, and the efficiency of the heat pump unit 10 decreases.
[0105]
So, in 4th Embodiment, the 45 degreeC warm water return position by the side of the floor heating apparatus 32 is set to the lower part of the 2nd hot water storage tank 17, and the 65 degreeC warm water return position by the bathroom heating apparatus 320 side is the 2nd hot water storage tank. 17 is set at an intermediate position in the vertical direction.
[0106]
Thereby, the return hot water of 45 ° C. on the floor heating device 32 side and the return hot water of 65 ° C. on the bathroom heating device 320 side are separately returned to the lower portion of the second hot water storage tank 17 and the intermediate position in the vertical direction, and the two temperatures It is possible to prevent mixing of different warm return water. As a result, the return hot water of 45 ° C. is supplied to the high-pressure side heat exchanger 13 of the heat pump unit 10 as it is, so that the efficiency of the heat pump unit 10 can be improved.
[0107]
In the third and fourth embodiments, the first three-way valve 21 is replaced with a two-way valve type normal on-off valve 21 ′ as in the second embodiment, and the first water supply passage 20 is connected to the on-off valve 21 ′. Of course, it may be separated and directly connected to the lower part of the first hot water storage tank 16.
[0108]
(Fifth embodiment)
In the fourth embodiment, using the high-temperature water in one second hot water storage tank 17 as a heat source, the heat radiation action of the floor heating device 32 and the bathroom heating device 320 is performed via the first and second brine heat exchangers 30 and 300. In the fifth embodiment, as shown in FIG. 13, two second hot water storage tanks 17 and 170 are provided in parallel to the first hot water storage tank 16, and one of the second hot water storage tanks 17 is provided. The floor heating device 32 is operated via the first brine heat exchanger 30 using the high-temperature water inside as a heat source, and the high-temperature water inside the second hot water storage tank 170 is used as the heat source via the second brine heat exchanger 300. Then, the bathroom heating device 320 is operated.
[0109]
Accordingly, in the fifth embodiment, a third three-way valve 210 similar to the first three-way valve 21 is added to the communication path below the second hot water storage tanks 17 and 170. In addition, a fourth three-way valve 43 for switching the supply of intermediate temperature water from the second hot water storage tanks 17 and 170 is added to the intermediate temperature water supply passage 25. Further, the fifth and sixth three-way valves 44 and 45 are added to the passage through which the high-temperature water heated by the high-pressure side heat exchanger 13 of the heat pump unit 10 is added, and the high temperature to the upper part of the second hot water storage tanks 17 and 170 is increased. The water supply is switched, the upper part of the second hot water storage tanks 17 and 170 and the hot water supply passage 23 are switched, and the like.
[Brief description of the drawings]
FIG. 1 is an overall system diagram of a first embodiment of the present invention.
FIG. 2 is a block diagram of electric control according to the first embodiment.
FIG. 3 is an operation explanatory diagram of the first embodiment.
FIG. 4 is an operation explanatory diagram of the first embodiment.
FIG. 5 is an operation explanatory diagram of the first embodiment.
FIG. 6 is an operation explanatory diagram of the first embodiment.
FIG. 7 is an operation explanatory diagram of the first embodiment.
FIG. 8 is an operation explanatory diagram of the first embodiment.
FIG. 9 is an operation explanatory diagram of the first embodiment.
FIG. 10 is an overall system diagram of a second embodiment.
FIG. 11 is an overall system diagram of a third embodiment.
FIG. 12 is an overall system diagram of a fourth embodiment.
FIG. 13 is an overall system diagram of a fifth embodiment.
[Explanation of symbols]
10 ... heat pump unit, 13 ... high pressure side heat exchanger,
16 ... 1st hot water storage tank, 17, 170 ... 2nd hot water storage tank, 18 ... Communication path,
20, 28 ... water supply passage, 21 ... three-way valve (blocking means),
21 '... open / close valve (shut-off means), 23 ... hot water supply passage, 24 ... hot water supply target device,
30, 300 ... Brine heating heat exchanger, 32 ... Floor heating device (heat dissipating device),
320 ... Bathroom heating device (heat dissipation device), 33, 330 ... Brine circulation circuit.

Claims

A heat pump unit (10) for heating hot water in the high-pressure side heat exchanger (13);
At least two hot water storage tanks (16, 16) having a tank upper part connected in parallel to the hot water outlet side of the high pressure side heat exchanger (13) and a tank lower part connected in parallel to the water inlet side of the high pressure side heat exchanger (13). 17, 170),
Of the at least two hot water storage tanks (16, 17, 170), a hot water supply passage (23) for supplying the hot water at the upper part of the first hot water storage tank (16) to the hot water supply target device (24),
A first water supply passage (20) for supplying water to at least the lower part of the first hot water storage tank (16);
Of the at least two hot water storage tanks (16, 17, 170), a heat exchanger (30, 300) for heating a brine for exchanging heat between the hot water and the brine at the top of the second hot water storage tank (17, 170);
A brine circulation circuit (33, 330) for circulating the brine heated in the heat exchanger (30, 300) for brine heating to the heat radiating device (32, 320),
The medium-temperature water radiated by passing through the brine heating heat exchanger (30, 300) is returned to the lower part of the second hot water storage tank (17, 170),
Furthermore, between the hot water storage tanks (16) (17, 170), a communication passage (18) that connects the lower part of the first hot water storage tank (16) and the lower part of the second hot water storage tank (17, 170). e Bei blocking means (21, 21 ') for blocking the communication,
The shut-off means (21, 21 ′) is used to supply hot water in the upper part of the first hot water storage tank (16) to the hot water supply target device (24) and to the lower part of the second hot water storage tank (17, 170). A heat pump type hot water supply apparatus that cuts off communication between the lower parts of the hot water storage tanks (16) (17, 170) when medium temperature water returns .

When the hot water in the hot water storage tanks (16) (17, 170) is boiled by the operation of the heat pump unit (10), the water temperature at the lower part of the first hot water storage tank (16) is changed to the second hot water storage tank (17). , 170), the communication between the lower portions of the hot water storage tanks (16), (17, 170) is blocked by the blocking means (21, 21 ′) while the temperature is lower than the water temperature at the lower portion of the first hot water storage tank ( 16) supplying the lower water of the high pressure side heat exchanger (13) to the water inlet side;
If the water temperature at the lower part of the first hot water storage tank (16) and the water temperature at the lower part of the second hot water storage tank (17, 170) are equal to each other at the time of boiling the hot water, the blocking means ( 21, 21 ′) is switched to a state of communication between the lower portions of the hot water storage tanks (16), (17, 170), and the water under the hot water storage tanks (16), (17, 170) is transferred to the high-pressure side heat. The heat pump type hot water supply apparatus according to claim 1 , wherein the heat pump type hot water supply apparatus is supplied to a water inlet side of the exchanger (13).

A circulation pump (22) for circulating hot water between the hot water storage tanks (16) (17, 170) and the high pressure side heat exchanger (13);
The hot water circulation flow rate by the circulation pump (22) is made smaller than the hot water circulation flow rate of natural convection due to a difference in hot water temperature between the hot water storage tanks (16, 17, 170). The heat pump type hot water supply apparatus described in 1.

The blocking means includes a three-way valve (21) that switches between the first water supply passage (20) and the communication passage (18).
The three-way valve (21) blocks communication between the lower portions of the hot water storage tanks (16) (17, 170), and connects the first water supply passage (20) to the lower portion of the first hot water storage tank (16). The first operating state that communicates and the second operating state that communicates between the lower portions of the hot water storage tanks (16) (17, 170) and closes the first water supply passage (20) are at least switched. The heat pump type hot water supply apparatus according to any one of claims 1 to 3 , wherein the heat pump type hot water supply apparatus is provided.

The first water supply passage (20) is directly connected to the lower part of the first hot water storage tank (16), and the blocking means is constituted by an on-off valve (21 ′) for opening and closing the communication passage (18). The heat pump type hot water supply apparatus according to any one of claims 1 to 3 .

The intermediate hot water supply passage (25) for supplying intermediate temperature water below the second hot water storage tank (17, 170) to the hot water supply passage (23), according to any one of claims 1 to 5 , Heat pump water heater.

A heat pump unit (10) for heating hot water in the high-pressure side heat exchanger (13);
At least two hot water storage tanks (16, 16) having a tank upper part connected in parallel to the hot water outlet side of the high pressure side heat exchanger (13) and a tank lower part connected in parallel to the water inlet side of the high pressure side heat exchanger (13). 17, 170),
Of the at least two hot water storage tanks (16, 17, 170), a hot water supply passage (23) for supplying the hot water at the upper part of the first hot water storage tank (16) to the hot water supply target device (24),
A first water supply passage (20) for supplying water to at least the lower part of the first hot water storage tank (16);
Of the at least two hot water storage tanks (16, 17, 170), a heat exchanger (30, 300) for heating a brine for exchanging heat between the hot water and the brine at the top of the second hot water storage tank (17, 170);
A brine circulation circuit (33, 330) for circulating the brine heated in the heat exchanger (30, 300) for brine heating to the heat radiating device (32, 320),
The medium-temperature water radiated by passing through the brine heating heat exchanger (30, 300) is returned to the lower part of the second hot water storage tank (17, 170),
Furthermore, the heat pump type hot water supply apparatus further comprising an intermediate temperature water supply passage (25) for supplying intermediate temperature water below the second hot water storage tank (17, 170) to the hot water supply passage (23).

A second water supply passage (28) for supplying water to the hot water supply passage (23);
Switching means (26) for switching between water supply from the second water supply passage (28) to the hot water supply passage (23) and medium temperature water supply from the intermediate temperature water supply passage (25) to the hot water supply passage (23); The heat pump type hot water supply apparatus according to claim 6 or 7 , further comprising:

A plurality of the brine heating heat exchangers (30, 300) are connected in parallel to the second hot water storage tank (17, 170),
A plurality of brine circulation circuits (33, 330) respectively corresponding to the plurality of brine heating heat exchangers (30, 300) are provided as the brine circulation circuits,
As the heat dissipation device, a plurality of heat dissipation devices (32, 320) respectively corresponding to the plurality of brine circulation circuits (33, 330) are provided,
Of the medium-temperature water that has passed through the plurality of brine heating heat exchangers (30, 300), medium-temperature water having a lower temperature is returned to the lower part of the second hot water storage tank (17, 170), and the medium-temperature water of, claims 1 and returning to a position higher than the hot water return position in the lower of the temperature of the hot water in the higher temperature for the second hot-water storage tank (17,170) 8 The heat pump type hot water supply apparatus according to any one of the above.

The heat pump type hot water supply device according to claim 9 , wherein one of the plurality of heat dissipating devices is a floor heating device (32) and the other is a bathroom heating device (320).

The heat pump hot water supply according to any one of claims 1 to 10 , wherein the heat pump unit (10) is configured by a supercritical refrigeration cycle in which a high-pressure side pressure is equal to or higher than a critical pressure of a refrigerant. apparatus.