JP3801122B2

JP3801122B2 - Heat pump water heater

Info

Publication number: JP3801122B2
Application number: JP2002259777A
Authority: JP
Inventors: 啓次郎國本; 竹司渡辺; 昌宏尾浜; 龍太近藤; 松本　　聡; 吉継西山; 浩二岡; 立群毛; 誠一安木; 春夫寺井
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2002-09-05
Filing date: 2002-09-05
Publication date: 2006-07-26
Anticipated expiration: 2022-09-05
Also published as: JP2004100978A

Description

【０００１】
【発明の属する技術分野】
本発明は、ヒートポンプ給湯装置に関するものである。
【０００２】
【従来の技術】
従来のヒートポンプ給湯装置としては、特許文献１に記載されているような給湯装置が提案されていた。この特許文献１におけるヒートポンプ給湯装置は図６に示すように、閉回路に構成される冷媒流路１で圧縮機２、放熱器３、減圧手段４、吸熱器５が接続された冷媒循環回路７と、放熱器３の冷媒流路ａ８と熱交換を行う水流路９を備えた熱交換器１０と、この水流路９に水道水を供給する給水管１１と、前記水流路９とシャワーや蛇口等の給湯端末１２とを接続する給湯回路１３と、給湯回路１３に設け給湯温度を検出する温度センサ１４と、圧縮機２の回転数を制御するインバータ１５を備え、圧縮機２を温度センサ１４の検出温度と設定温度との差に応じてインバータ１５の出力周波数を変換するようにしていた。すなわち従来の給湯装置では設定温度に対して給湯温度が低い場合は圧縮機２の回転数を上げ、給湯温度が高い場合は回転数を下げるように制御するようにしていた。
【０００３】
【特許文献１】
特開平２−２２３７６７号公報
【０００４】
【発明が解決しようとする課題】
しかし、上記従来例の給湯装置の構成では、給湯時における給湯負荷が一定ではない。特に流量は使用者が給湯目的によってさまざまに変化させるために給湯負荷は大きく変ってしまう。例えば家庭用の給湯の場合、シャワーや風呂への湯張りに給湯する場合は１０〜２０Ｌ／ｍｉｎの大流量となるが、台所で食器を洗う場合や洗面への給湯では３〜５Ｌ／ｍｉｎと少流量である。また、季節による給水温度の変化によっても給湯負荷は大きく変る。
【０００５】
こうした流量や水温の変化により大きくかわる給湯負荷を、従来のヒートポンプ給湯装置のように給湯温度と設定温度の差により圧縮機の回転数を変えて給湯熱量を制御するだけでは、給湯負荷がヒートポンプ装置の給湯加熱能力を超えてしまうと、目標とする温度より低い温度の湯が出てしまい、使用者に不快感を与えてしまう問題があった。
【０００６】
また、従来例のようなヒートポンプ給湯装置は給湯の開始時に冷媒循環回路全体の圧力や温度の立上がりに時間を要するため、熱交換器の水流路からの出湯温度の上昇に遅れが生じる。この給湯開始時に従来の構成では、給湯温度と設定温度の差だけで圧縮機の回転数を設定するだけなので、大流量の給湯では目標の湯温に達するのに時間がかかっていた。
【０００７】
以上のように従来のヒートポンプ給湯装置では大流量などの給湯負荷が大きい場合に目標温度の給湯ができなかったり、目標温度に達するのに時間がかかったりといった問題があった。
【０００８】
本発明は、上記従来の課題を解決するもので、湯温の制御性がよく、湯温の立上りの早いヒートポンプ給湯装置を提供することを目的とする。
【０００９】
【課題を解決するための手段】
本発明は上記課題を解決するために、本発明のヒートポンプ給湯装置は、圧縮機と放熱器と減圧手段と吸熱器とを含む冷媒循環回路と、前記放熱器と熱交換を行う水流路を備えた熱交換器と、前記水流路に水道水を供給する給水管と、前記水流路から給湯端末へと通水するように接続する給湯回路と、前記水流路の水量を調節する水量調節手段と、前記熱交換器で加熱された水道水を前記給湯回路を経由して直接前記給湯端末から出湯させる経路と、給湯負荷が前記冷媒循環回路としての最大能力を超える場合には水流路の水量を調節する水量調節手段とを有し、給湯が停止してから所定時間が経過したかを判定し、所定時間を経過している時には、給湯開始時には前記水量調節手段を予め所定量だけ絞った初期開度に設定し、所定時間を経過していない時には水量調節手段を予め所定量だけ絞った初期開度に設定しないことを特徴とするヒートポンプ給湯装置とする。
【００１０】
この発明によれば、水量調節手段が水流路の水量を調節して給湯を行うので、給湯負荷が冷媒循環回路としての最大能力を超える場合でも、能力に見合った水量に調整することにより、所定の温度の給湯が可能となる。また、給湯開始時の出湯温度の上昇も早くなる。
【００１１】
【発明の実施の形態】
請求項１に記載の発明のヒートポンプ給湯装置は、圧縮機と放熱器と減圧手段と吸熱器とを含む冷媒循環回路と、前記放熱器と熱交換を行う水流路を備えた熱交換器と、前記水流路に水道水を供給する給水管と、前記水流路から給湯端末へと通水するように接続する給湯回路と、前記水流路の水量を調節する水量調節手段と、前記熱交換器で加熱された水道水を前記給湯回路を経由して直接前記給湯端末から出湯させる経路と、給湯負荷が前記冷媒循環回路としての最大能力を超える場合には水流路の水量を調節する水量調節手段とを有し、給湯が停止してから所定時間が経過したかを判定し、所定時間を経過している時には、給湯開始時には前記水量調節手段を予め所定量だけ絞った初期開度に設定し、所定時間を経過していない時には水量調節手段を予め所定量だけ絞った初期開度に設定しないことを特徴とするヒートポンプ給湯装置とする。
【００１２】
この発明によれば、水量調節手段により熱交換器の水流路を流れる水量を調整するので、給湯負荷が冷媒循環回路の熱交換器の最大能力を超える場合でも、水量を低下させることにより給湯負荷を最大能力より低く抑えることができ、出湯温度が下がることなく所定温度を維持することができる。また、給湯が停止してから所定時間が経過したかを判定し、所定時間を経過している時には、水量調節手段を予め所定量だけ絞った初期開度に設定することにより、給湯開始時における冷媒循環回路の温度や圧力の立ち上がり時間は、水流路に流れる水量が多いと熱交換器から取られる熱量も多くなるために長くなる。そのため、水流路からの出湯温度の上昇速度も遅くなり、目標温度に到達するまでに長い時間を要するが、本発明によれば、給湯開始時に水量調節手段により水量を低下させるので、冷媒循環回路や熱交換器の温度上昇を早め、出湯温度が目標温度に到達する時間を短縮することができる。
【００１３】
請求項２に記載の発明のヒートポンプ給湯装置は、請求項１記載の構成に、給湯回路への給湯熱量である給湯負荷を求める給湯負荷検知手段と、熱交換器での加熱量を検知する熱量検知手段とを設け、前記給湯負荷検知手段の値が前記熱量検知手段の値を超える場合に水量調整手段により水量を低下させるものである。
【００１４】
この発明によれば、給湯負荷と加熱量を比較して給湯負荷に対して加熱量が不足する場合に流量を低下させて、出湯温度の低下を防止するものである。したがって、必要な場合だけ流量を低下させるので、通常の給湯負荷では流量低下がなく、例えばシャワーと台所の給湯が重なったりした、大流量での使用時に加熱量が不足した場合のみ流量を低下させるので、流量低下の頻度を最小限に抑えることができる。
【００１５】
請求項３に記載の発明のヒートポンプ給湯装置は、請求項２の構成に給水管の給水温度を検出する水温検知手段と、給湯の目標温度を設定する温度設定手段と、給湯回路の流量を検出する流量検知手段とを設け、請求項２に記載の給湯負荷検知手段を、前記水温検知手段と温度設定手段と流量検知手段の値の少なくともひとつから給湯負荷を求めるようにしたものである。
【００１６】
給湯負荷は、給湯の目標温度と給水温度との偏差に流量を乗じた値に比例するので、本発明によれば、前記水温検知手段と温度設定手段と流量検知手段の値から給湯負荷を算定することにより、正確な給湯負荷を求めることができる。
【００１７】
請求項４に記載の発明のヒートポンプ給湯装置は、請求項２または３に記載の構成に外気温度を検出する外気温度検知手段と、給水管の給水温度を検出する水温検知手段と、給湯の目標温度を設定する温度設定手段とを設け、請求項２または３に記載の熱量検知手段を、前記外気温度検知手段と水温検知手段と温度設定手段の値の少なくともひとつから熱交換器での加熱量を求めるようにしたものである。
【００１８】
この発明の冷媒循環回路の熱交換器での最大加熱量は、外気温度と給水温度と目標温度の３点の条件でほぼ求まるので、この３点から最大加熱量を正確に求めることができる。したがって、この値と給湯負荷を比較すれば、熱量不足が判定できる。
【００１９】
請求項５に記載の発明のヒートポンプ給湯装置は、請求項２〜４のいずれか１項に記載の水量調節手段による水量低下量を、給湯負荷検知手段の値と熱量検知手段の値とが一致するように水量を低下させるようにしたものである。
【００２０】
この発明によれば、最小限の水量低下で目標の出湯温度が得られる。
【００２１】
【実施例】
以下本発明の実施例について、図面を参照しながら説明する。なお、従来例および各実施例において、同じ構成、同じ動作をする部分については同一符号を付与し、詳細な説明を省略する。
【００２２】
（実施例１）
図１は本発明の実施例１におけるヒートポンプ式給湯装置の構成図である。図１において、７は冷媒循環回路で、圧縮機２、放熱器３、減圧手段４、吸熱器５が冷媒流路１により閉回路に接続されている。この冷媒循環回路７は、例えば炭酸ガス（ＣＯ２）を冷媒として使用し、高圧側の冷媒圧力が冷媒の臨界圧以上となる超臨界ヒートポンプサイクルを使用している。そして圧縮機２は、内蔵する電動モータ（図示しない）によって駆動され、吸引した冷媒を臨界圧力を超える圧力まで圧縮して吐出する。また、１０は放熱器３の冷媒流路ａ８と熱交換を行う水流路９を備えた熱交換器である。この水流路９に水道水を直接供給する給水管１１と、水流路９から出湯される湯をシャワー１６や蛇口１７等より成る給湯端末１２の通水させるための給湯回路１３が接続されている。そして１８は水流路９の水量を調節する水量調節手段で、電動の絞り弁により構成され給水管１１に設けている。
【００２３】
１９は制御手段で、給湯回路１３への給湯熱量である給湯負荷を求める給湯負荷検知手段２０と、熱交換器１０での水流路９の加熱量を検知する熱量検知手段２１と、圧縮機の周波数と減圧手段とを制御する加熱制御手段２２とを有している。
【００２４】
制御手段１９は、予め水量調節手段１８である絞り弁を所定量だけ駆動させ、給湯開始時の水量を低下させるように制御するとともに、給湯負荷検知手段２０の値が熱量検知手段２１の値を超える場合に、給湯負荷検知手段２０の値が熱量検知手段２１の値と一致するように水量調整手段１８により水流路９の水量を低下させるように制御する。
【００２５】
給水管１１には、給湯回路１３の流量を検出する流量検知手段２３と、熱交換器１０への給水温度を検出する水温検知手段２４が設けられている。そして給湯回路１３には水流路９からの出湯温度を検出する湯温検知手段２５が設けられている。２６は給湯の目標温度を設定する温度設定手段で、使用者が任意に温度を設定する。２７は気温を検出する外気温度検知手段である。
【００２６】
熱交換器１０は、冷媒流路ａ８の流れ方向と水流路９の流れ方向を対向流とし、各流路間を熱移動が容易になるように密着して構成している。この構成により冷媒流路ａ８と水流路９の伝熱が均一化し、熱交換効率がよくなる。また、高温の出湯も可能になる。
【００２７】
加熱制御手段２２は、圧縮機２の回転数を変更する周波数制御手段２８を備え、湯温検知手段２５と温度設定手段２６とのそれぞれが出力する出湯温度と目標温度との偏差が少なくなるように圧縮機２の周波数を公知のＰＩＤ（図示せず）により制御する。また、加熱制御手段２２は圧縮機２の冷媒吐出温度が所定の温度で、かつ冷媒循環回路７の圧力バランスを適性になるように減圧手段４の開度を制御する。
【００２８】
図２は実施例１における給湯開始時の水量調整手段１８の制御フローチャートである。図２において、３０は給湯中であるかを判定する。判定条件は流量検知手段２３が水量を検知したら給湯中と判定する。そして、水量がなく停止中と判定した場合は、３１に進む。ここでは給湯が停止してから１０分が経過したかを判定し、１０分が経過していれば、３２で水量調整手段１８の初期開度６０％を設定する。３１で１０分未満であると判定された場合は、３２の初期開度の設定を行わない。３１における１０分は、給湯の再起動時に水量を減少させて行うかどうかを決定する時間であり、冷媒循環回路７および熱交換器１０の冷却速度により設定するもので、冷えやすい条件であれば短い時間を設定し、冷えにくい条件であれば長い時間を設定するものである。
【００２９】
３０において給湯中と判定されれば３４へ進み、ここでは給湯開始から５分が経過したかどうかを判定し、５分が経過していれば、３５で水量調整手段１８の開度を全開１００％に戻す設定を行う。３４で５分未満であっても、３６で出湯温度Ｔｈｗが目標温度Ｔｓｅｔ−５Ｋを超えていれば、３５で水量調整手段１８の開度を全開に戻す設定を行う。そして、３４と３６の条件が成り立たない場合は水量調整手段１８の開度は初期開度のままとなる。
【００３０】
なお３２における初期開度６０％は、使用者に違和感なく水量を低減できるレベルで、出湯温度の立上りが早くなる値に設定する必要があり、予め実験的に決定すべき値である。
【００３１】
図３は実施例１における給湯時の水量調整手段１８の制御フローチャートである。図３において、４０は給湯負荷検知手段２０の給湯負荷算定を示す。ここでは、水温検知手段２４の検出する水温Ｔｗ（℃）と温度設定手段２６の設定する目標温度Ｔｓｅｔ（℃）との差に、流量検知手段２３の検出する流量Ｗ（Ｌ／ｍｉｎ）を乗じて、これに変換係数（６０／８６０）を乗じて給湯負荷Ｑｈｗ（ｋＷ）を求めている。なお、算出精度は悪くなるが給湯負荷の算定は水温を代表的な固定値としてもよいし、目標温度を固定値としてもよい。これによれば水温検知手段２４や温度設定手段２６が不要になったり、故障時でも稼動できたりする。
【００３２】
４１では熱量検知手段２１での加熱量Ｑｈｘ（ｋＷ）の設定を示す。これは、外気温度検知手段２７の検出する外気温度Ｔｏ（℃）と水温検知手段２４の水温Ｔｗから加熱量のテーブル４２から加熱量Ｑｈｘを読み込む。このテーブル４２の値は外気温度と水温の組合わせ条件における最大加熱量を予め実験により求めて設定しておく。このテーブルは数式でもよい。また、外気温度と水温と目標温度の３元の加熱量のテーブルとしてもよいし、外気温度と水温と目標温度の中から別の２つの要素からなる２元のデータでもよいし、加熱量の制度は悪くなるが、それぞれひとつの要素だけの１元のテーブルでもよい。これにより実験量が少なくかつメモリーが小さくできる。
【００３３】
４３は給湯負荷Ｑｈｗが加熱量Ｑｈｘを超える条件の場合は、４４で水量調整手段１８による水量低下のための開度低減設定を行う。一方４３でＱｈｗの方がＱｈｘより小さければ、４５で水量調整手段１８による水量復帰のための開度増加設定を行う。ここでの制御は、給湯負荷が加熱量を超える条件の場合に、給湯負荷が加熱量と一致するように水量を低下させるように作用する。そして４６、４７で開度低減の上限値を定め、４８，４９で開度低減の下限値を定めている。下限値として−７０％を設定しているのは異常時等により水量調整手段１８の絞りが進んでも最低３０％の開度を確保して、全閉になって給湯停止に到らないようにしている。
【００３４】
５０は水量調整手段１８の開度設定を行う。ここで図２で説明した給湯開始時の開度Ｘｉに低減開度Ｘｄを加算して最終の開度設定Ｘを求める。そして、５１で水量調整手段１８を設定された開度に駆動する。
【００３５】
以上の構成において、その動作、作用について説明する。蛇口１７が開かれると給水管１１から水道水が流れ込み始める。これを流量検知手段２３が検知し制御手段１９に信号が送られ、圧縮機２が起動する。
【００３６】
このとき水量調整手段１８は初期開度に絞られているので、水量は抑制されて出湯される。したがって、冷媒循環回路７の放熱手段３から水流路９への熱交換量が抑制せれ、圧縮機２や熱交換器１０の温度上昇速度が早くなり、水流路９からの出湯温度の温度上昇速度が早くなる。そして出湯温度が（目標温度−５Ｋ）以上に上昇したら水量調整手段１８により絞られた初期開度が解除されて、全開に復帰する。このとき圧縮機２や熱交換器１０は十分に圧力や温度が上昇しているので、水量を復帰させても出湯温度が低下することなく目標温度に到達することができる。
【００３７】
加熱制御手段２２では出湯温度と目標温度との偏差に基づいて圧縮機２の周波数を制御する。そして、圧縮機２から吐出される高温高圧の冷媒ガスは放熱器３へ流入し、水流路９を流れる水を加熱する。そして、加熱された水は給湯回路１３を経て給湯端末１２から出湯する。一方、放熱器３で冷却された冷媒は減圧手段４で減圧されて吸熱器５に流入し、ここで大気熱、太陽熱など自然エネルギーを吸熱して蒸発ガス化し、圧縮機２に戻る。従って、出湯を検出して、すぐに圧縮機１からの高温高圧の冷媒ガスが放熱器３に流入し、水を加熱し、そのまま給湯端末１２から出湯利用できる。
【００３８】
給湯中の加熱制御手段２２では、出湯温度と目標温度との偏差から公知のＰＩＤ制御を用いて周波数を算定する。すなわち、出湯温度のフィードバック制御がおこなわれる。ここでの制御定数である比例ゲインや積分係数や微分係数は、制御の応答性と安定性を両立するための最適な値を予め設定しておく必要がある。なおフィードバック制御は、ＰＩ制御でもＰ制御でもファジーやニューロ制御でもよい。
【００３９】
給湯中に２ヶ所以上の給湯などの大流量での給湯が発生し、熱交換器１０での最大加熱量を超える給湯負荷が発生した場合は、制御手段１９が水量調整手段１８を絞り方向に駆動し、給湯負荷が最大加熱量とほぼ一致するまで水量を減少させるので、出湯温度は大幅に低下することなく目標温度を維持することができる。
【００４０】
また、大流量から通常の流量へと変化した場合でも、給湯負荷が最大加熱量を下回れば、水量調整手段１８での絞りは水量低下から水量復帰に変り全開運転に戻るので使用者に違和感なく給湯運転ができる。
【００４１】
なお、実施例１では冷媒循環回路を、冷媒の圧力が臨界圧力以上となる超臨界冷媒循環回路としたが、もちろん一般の臨界圧力以下の冷媒循環回路でもよい。
【００４２】
（実施例２）
図４は本発明の実施例２におけるヒートポンプ給湯装置の給湯時の水量調整手段１８の制御フローチャートである。なお、実施例１の給湯装置と同一構造のものは同一符号を付与し、説明を省略する。図４において、実施例１の構成と異なるところは、５５の水量上限の設定値により水量調整手段１８の制御を行う点にある。５５では４１により求めた最大の加熱量Ｑｈｘ（ｋＷ）と目標温度Ｔｓｅｔ（℃）と水温Ｔｗ（℃）より水量の上限ＷＬ（Ｌ／ｍｉｎ）を算出する。そして、５６により流量検知手段２３により検出された水量Ｗ（Ｌ／ｍｉｎ）が水量の上限ＷＬを超えないかを判定し、超えた場合は４４で水量調整手段１８による水量低下のための開度低減設定を行う。一方超えない場合は、４５で水量調整手段１８による水量復帰のための開度増加設定を行う。
【００４３】
以上のように実施例２では、最大の加熱量から水量の上限を設定し、水量の検出値がこの上限を超えないように制御するので、加熱量不足による出湯温度低下が防止できる。
【００４４】
（実施例３）
図５は本発明の実施例３におけるヒートポンプ給湯装置の給湯時の水量調整手段１８の制御フローチャートである。なお、実施例１の給湯装置と同一構造のものは同一符号を付与し、説明を省略する。図５において、実施例１の構成と異なるところは、温度設定手段２６の設定する目標温度より５Ｋ低い第２の目標値を設定し、給湯開始から３分経過以降に出湯温度が、この第２の目標温度以下でかつ、加熱制御手段２２が圧縮機２の周波数を上限に設定した場合に水量を低下させる点にある。具体的に次のような制御となる。
【００４５】
６０では加熱制御手段２２の圧縮機２の周波数設定が行われる。すなわち出湯温度Ｔｈｗと目標温度Ｔｓｅｔとの偏差から公知のＰＩＤ制御を用いて周波数Ｆを算定する。
【００４６】
６１は給湯開始から３分経過したかを判定する。３分未満であれば、６２で水量低下の開度低減設定は０％とし、水量低下禁止とする。６１で３分以上経過したと判定すると、６３に進む。
【００４７】
６３は圧縮機２の制御周波数Ｆが上限値Ｆｍａｘ以上で、出湯温度Ｔｈｗが目標温度Ｔｓｅｔ−３Ｋ未満であれば、４４で水量調整手段１８による水量低下のための開度低減設定を行う。一方６３の条件が成り立たない場合は、４５で水量調整手段１８による水量復帰のための開度増加設定を行う。
【００４８】
６１の給湯開始から３分は、まだシステム全体の能力や温度が立ち上がるまでの時間を設定するもので、この値はシステムの条件により異なる。
【００４９】
６３における判定は周波数Ｆにより最大加熱量に達しているかを判定し、出湯温度Ｔｈｗにより能力不足かどうかを判定している。そして、この両者により、最大加熱量に達して能力不足に陥っていると判定される。なお、実施例３では周波数Ｆと出湯温度Ｔｈｗの両者の状態で判定することにより、判定精度を向上させているが、それぞれ単独で判定しても充分に精度よく能力不足を判定できる。
【００５０】
なお、上記１〜３の実施例では貯湯槽や蓄熱材を持たない、完全な瞬間式の給湯装置で説明したが、給湯時にヒートポンプで加熱した湯を直接給湯端末に供給する構成であれば、熱交換器に並列に貯湯槽を有していたり、また熱交換器に直列に貯湯槽を有していたり、さらには水側回路や冷媒回路に蓄熱材を有していても同様の効果が得られる。
【００５１】
【発明の効果】
以上のように、本発明によれば、給湯制御の応答性と安定性がよいヒートポンプ給湯装置を提供することができる。
【図面の簡単な説明】
【図１】本発明の実施例１におけるヒートポンプ給湯装置の構成図
【図２】本発明の実施例１における給湯開始時の水量調整手段の制御フローチャート
【図３】本発明の実施例１における給湯時の水量調整手段の制御フローチャート
【図４】本発明の実施例２における給湯時の水量調整手段の制御フローチャート
【図５】本発明の実施例３における給湯時の水量調整手段の制御フローチャート
【図６】従来のヒートポンプ給湯装置の構成図
【符号の説明】
２圧縮機
３放熱器
４減圧手段
５吸熱器
７冷媒循環回路
９水流路
１０熱交換器
１１給水管
１２給湯端末
１３給湯回路
１８水量調整手段
２０給湯負荷検知手段
２１熱量検知手段
２２加熱制御手段
２３流量検知手段
２４水温検知手段
２５湯温検知手段
２６温度設定手段
２７外気温度検知手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat pump water heater.
[0002]
[Prior art]
As a conventional heat pump hot water supply apparatus, a hot water supply apparatus as described in Patent Document 1 has been proposed. As shown in FIG. 6, the heat pump hot water supply apparatus in Patent Document 1 includes a refrigerant circulation circuit 7 in which a compressor 2, a radiator 3, a decompression unit 4, and a heat absorber 5 are connected by a refrigerant flow path 1 configured in a closed circuit. A heat exchanger 10 having a water channel 9 for exchanging heat with the refrigerant channel a8 of the radiator 3, a water supply pipe 11 for supplying tap water to the water channel 9, and the water channel 9 and a shower or faucet A hot water supply circuit 13 for connecting the hot water supply terminal 12 such as a temperature sensor 14 provided in the hot water supply circuit 13 for detecting the hot water supply temperature, and an inverter 15 for controlling the rotation speed of the compressor 2. The output frequency of the inverter 15 is converted according to the difference between the detected temperature and the set temperature. That is, in the conventional hot water supply apparatus, the control is performed such that the rotation speed of the compressor 2 is increased when the hot water supply temperature is lower than the set temperature, and the rotation speed is decreased when the hot water supply temperature is high.
[0003]
[Patent Document 1]
JP-A-2-223767
[Problems to be solved by the invention]
However, in the configuration of the conventional hot water supply apparatus, the hot water supply load during hot water supply is not constant. In particular, since the flow rate is varied by the user depending on the purpose of hot water supply, the hot water supply load changes greatly. For example, in the case of hot water supply for home use, a large flow rate of 10 to 20 L / min is used when supplying hot water to a shower or bath, but 3 to 5 L / min for washing dishes in the kitchen or hot water supply to the wash surface. Small flow rate. Also, the hot water supply load varies greatly depending on the seasonal change in the temperature of the water supply.
[0005]
A hot water supply load that changes greatly due to changes in flow rate and water temperature can be controlled by changing the number of rotations of the compressor according to the difference between the hot water supply temperature and the set temperature as in conventional heat pump hot water supply devices. If the hot water heating capacity is exceeded, hot water having a temperature lower than the target temperature will be produced, which may cause discomfort to the user.
[0006]
In addition, since the heat pump hot water supply apparatus as in the conventional example takes time to rise in the pressure and temperature of the entire refrigerant circulation circuit at the start of hot water supply, there is a delay in the rise of the hot water temperature from the water flow path of the heat exchanger. In the conventional configuration at the start of this hot water supply, since the rotation speed of the compressor is only set based on the difference between the hot water supply temperature and the set temperature, it takes time to reach the target hot water temperature for hot water supply with a large flow rate.
[0007]
As described above, the conventional heat pump hot water supply apparatus has problems such as being unable to supply hot water at a target temperature when a hot water supply load such as a large flow rate is large, or taking time to reach the target temperature.
[0008]
The present invention solves the above-described conventional problems, and an object of the present invention is to provide a heat pump hot water supply apparatus that has good controllability of hot water temperature and has a rapid rise in hot water temperature.
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems, the heat pump water heater of the present invention includes a refrigerant circuit including a compressor, a radiator, a decompression unit, and a heat absorber, and a water flow path that performs heat exchange with the radiator. A heat exchanger, a water supply pipe for supplying tap water to the water flow path, a hot water supply circuit connected so as to pass water from the water flow path to the hot water supply terminal, and a water amount adjusting means for adjusting a water amount of the water flow path, A route for discharging tap water heated by the heat exchanger directly from the hot water supply terminal via the hot water supply circuit, and when the hot water supply load exceeds the maximum capacity as the refrigerant circulation circuit, A water amount adjusting means for adjusting , determining whether a predetermined time has elapsed since the hot water supply was stopped, and when the predetermined time has elapsed, at the start of hot water supply , the water amount adjusting means is initially reduced by a predetermined amount. set opening, after a predetermined time The heat pump water heater, characterized in that when you are not are not set to an initial opening squeezed by previously predetermined amount water amount adjusting means.
[0010]
According to this invention, since the water amount adjusting means adjusts the amount of water in the water flow path to perform hot water supply, even if the hot water supply load exceeds the maximum capacity as the refrigerant circulation circuit, the water amount is adjusted to the water amount suitable for the capacity, Hot water supply at a temperature of Moreover, the rise of the hot water temperature at the start of hot water supply is also accelerated.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The heat pump hot water supply apparatus of the invention described in claim 1 is a refrigerant circulation circuit including a compressor, a radiator, a decompression unit, and a heat absorber, a heat exchanger provided with a water flow path for exchanging heat with the radiator, A water supply pipe for supplying tap water to the water flow path, a hot water supply circuit connected so as to pass water from the water flow path to a hot water supply terminal, a water amount adjusting means for adjusting the amount of water in the water flow path, and the heat exchanger A route for directly discharging heated tap water from the hot water supply terminal via the hot water supply circuit, and a water amount adjusting means for adjusting the amount of water in the water flow path when the hot water supply load exceeds the maximum capacity as the refrigerant circulation circuit; It is determined whether or not a predetermined time has elapsed since the hot water supply was stopped, and when the predetermined time has elapsed , the water amount adjusting means is set to an initial opening previously throttled by a predetermined amount at the start of hot water supply. When the specified time has not elapsed, The heat pump water heater, characterized in that no setting adjustment means in advance predetermined amount squeezed initial opening.
[0012]
According to this invention, since the amount of water flowing through the water flow path of the heat exchanger is adjusted by the water amount adjusting means, even when the hot water supply load exceeds the maximum capacity of the heat exchanger of the refrigerant circulation circuit, the hot water supply load is reduced by reducing the water amount. Can be kept lower than the maximum capacity, and the predetermined temperature can be maintained without lowering the tapping temperature. Further, it is determined whether a predetermined time has elapsed since the hot water supply was stopped, and when the predetermined time has elapsed, the water amount adjusting means is set to an initial opening previously throttled by a predetermined amount, thereby The rise time of the temperature and pressure of the refrigerant circulation circuit becomes longer because the amount of heat taken from the heat exchanger increases when the amount of water flowing through the water flow path is large. Therefore, the rising speed of the hot water temperature from the water flow path also slows down, and it takes a long time to reach the target temperature. However, according to the present invention, the water amount is reduced by the water amount adjusting means at the start of hot water supply. And the temperature rise of the heat exchanger can be accelerated, and the time for the tapping temperature to reach the target temperature can be shortened.
[0013]
A heat pump hot water supply apparatus according to a second aspect of the present invention is the same as that of the first aspect, wherein a hot water supply load detecting means for obtaining a hot water supply load which is the amount of hot water supply to the hot water supply circuit, and an amount of heat for detecting the amount of heating in the heat exchanger. Detecting means, and when the value of the hot water supply load detecting means exceeds the value of the heat quantity detecting means, the water amount is reduced by the water amount adjusting means.
[0014]
According to the present invention, the hot water supply load and the heating amount are compared, and when the heating amount is insufficient with respect to the hot water supply load, the flow rate is reduced to prevent the temperature of the hot water from being lowered. Therefore, since the flow rate is reduced only when necessary, the flow rate does not decrease under normal hot water supply load.For example, the flow rate is reduced only when the amount of heating is insufficient when using a large flow rate, such as when showers and hot water in the kitchen overlap. Therefore, the frequency of flow rate reduction can be minimized.
[0015]
A heat pump hot water supply apparatus according to a third aspect of the present invention is a water temperature detection means for detecting the water supply temperature of the water supply pipe, a temperature setting means for setting a target temperature of the hot water supply, and a flow rate of the hot water supply circuit. The hot water supply load detection means according to claim 2 is configured to obtain a hot water supply load from at least one of the values of the water temperature detection means, the temperature setting means, and the flow rate detection means.
[0016]
Since the hot water supply load is proportional to a value obtained by multiplying the deviation between the target temperature of hot water supply and the temperature of the hot water by the flow rate, according to the present invention, the hot water supply load is calculated from the values of the water temperature detection means, the temperature setting means, and the flow rate detection means. By doing so, an accurate hot water supply load can be obtained.
[0017]
A heat pump hot water supply apparatus according to a fourth aspect of the present invention is the configuration of the second or third aspect, wherein the outside air temperature detecting means for detecting the outside air temperature, the water temperature detecting means for detecting the water supply temperature of the water supply pipe, and the hot water supply target A temperature setting means for setting the temperature is provided, and the heat quantity detection means according to claim 2 is changed from at least one of the values of the outside air temperature detection means, the water temperature detection means, and the temperature setting means to a heating amount in the heat exchanger. Is to ask for.
[0018]
Since the maximum amount of heating in the heat exchanger of the refrigerant circuit according to the present invention is almost determined under the three conditions of the outside air temperature, the feed water temperature, and the target temperature, the maximum amount of heating can be accurately determined from these three points. Therefore, if this value is compared with the hot water supply load, it can be determined that the amount of heat is insufficient.
[0019]
A heat pump hot water supply apparatus according to a fifth aspect of the present invention is such that the amount of water decrease by the water amount adjusting means according to any one of claims 2 to 4 is equal to the value of the hot water supply load detecting means and the value of the heat quantity detecting means. In this way, the amount of water is reduced.
[0020]
According to this invention, the target hot water temperature can be obtained with a minimum reduction in the amount of water.
[0021]
【Example】
Embodiments of the present invention will be described below with reference to the drawings. In the conventional example and each example, parts having the same configuration and the same operation are denoted by the same reference numerals, and detailed description thereof is omitted.
[0022]
Example 1
FIG. 1 is a configuration diagram of a heat pump type hot water supply apparatus in Embodiment 1 of the present invention. In FIG. 1, reference numeral 7 denotes a refrigerant circulation circuit, in which a compressor 2, a radiator 3, a decompression unit 4, and a heat absorber 5 are connected to a closed circuit by a refrigerant flow path 1. The refrigerant circuit 7 uses, for example, carbon dioxide (CO2) as a refrigerant, and uses a supercritical heat pump cycle in which the refrigerant pressure on the high-pressure side is equal to or higher than the critical pressure of the refrigerant. The compressor 2 is driven by a built-in electric motor (not shown), and compresses and sucks the sucked refrigerant to a pressure exceeding the critical pressure. Reference numeral 10 denotes a heat exchanger provided with a water channel 9 for exchanging heat with the refrigerant channel a8 of the radiator 3. A water supply pipe 11 for directly supplying tap water to the water flow path 9 and a hot water supply circuit 13 for passing hot water discharged from the water flow path 9 through a hot water supply terminal 12 including a shower 16 and a faucet 17 are connected. . Reference numeral 18 denotes a water amount adjusting means for adjusting the amount of water in the water flow path 9, which is constituted by an electric throttle valve and provided in the water supply pipe 11.
[0023]
Reference numeral 19 denotes a control means, a hot water supply load detection means 20 for obtaining a hot water supply load which is the amount of hot water supply to the hot water supply circuit 13, a heat quantity detection means 21 for detecting the heating amount of the water flow path 9 in the heat exchanger 10, and a compressor. Heating control means 22 for controlling the frequency and the decompression means is provided.
[0024]
The control means 19 drives the throttle valve, which is the water amount adjusting means 18, by a predetermined amount in advance so as to reduce the amount of water at the start of hot water supply, and the value of the hot water supply load detection means 20 sets the value of the heat quantity detection means 21. When exceeding, the water amount adjusting means 18 controls the water flow rate of the water flow path 9 to be lowered so that the value of the hot water supply load detecting means 20 matches the value of the heat amount detecting means 21.
[0025]
The water supply pipe 11 is provided with a flow rate detection means 23 for detecting the flow rate of the hot water supply circuit 13 and a water temperature detection means 24 for detecting the temperature of the water supply to the heat exchanger 10. The hot water supply circuit 13 is provided with hot water temperature detection means 25 for detecting the temperature of the hot water discharged from the water flow path 9. Reference numeral 26 denotes temperature setting means for setting a target temperature for hot water supply, and the user arbitrarily sets the temperature. Reference numeral 27 denotes an outside air temperature detecting means for detecting the air temperature.
[0026]
The heat exchanger 10 is configured so that the flow direction of the refrigerant flow path a8 and the flow direction of the water flow path 9 are opposed to each other, and the flow paths are in close contact with each other so as to facilitate heat transfer. With this configuration, heat transfer between the refrigerant flow path a8 and the water flow path 9 is made uniform, and heat exchange efficiency is improved. In addition, hot water can be discharged.
[0027]
The heating control means 22 includes a frequency control means 28 for changing the rotation speed of the compressor 2 so that the deviation between the hot water temperature output from the hot water temperature detection means 25 and the temperature setting means 26 and the target temperature is reduced. Further, the frequency of the compressor 2 is controlled by a known PID (not shown). Further, the heating control means 22 controls the opening degree of the decompression means 4 so that the refrigerant discharge temperature of the compressor 2 is a predetermined temperature and the pressure balance of the refrigerant circulation circuit 7 becomes appropriate.
[0028]
FIG. 2 is a control flowchart of the water amount adjusting means 18 at the start of hot water supply in the first embodiment. In FIG. 2, 30 determines whether hot water is being supplied. The determination condition is that hot water is being supplied when the flow rate detection means 23 detects the amount of water. And when it determines with there being no water quantity and being stopped, it progresses to 31. Here, it is determined whether 10 minutes have elapsed since the hot water supply was stopped. If 10 minutes have elapsed, the initial opening 60% of the water amount adjusting means 18 is set at 32. If it is determined at 31 that it is less than 10 minutes, the initial opening of 32 is not set. 10 minutes in 31 is a time for determining whether or not to reduce the amount of water when restarting hot water supply, and is set according to the cooling rate of the refrigerant circulation circuit 7 and the heat exchanger 10, so long as it is easy to cool A short time is set, and if it is difficult to cool, a long time is set.
[0029]
If it is determined at 30 that hot water is being supplied, the process proceeds to 34. Here, it is determined whether or not 5 minutes have elapsed since the start of hot water supply. If 5 minutes have elapsed, the opening of the water amount adjusting means 18 is fully opened at 35. Set to%. Even if it is less than 5 minutes at 34, if the hot water temperature Thw exceeds the target temperature Tset-5K at 36, the opening of the water amount adjusting means 18 is set to fully open at 35. And when the conditions of 34 and 36 are not satisfied, the opening degree of the water quantity adjusting means 18 remains the initial opening degree.
[0030]
The initial opening 60% at 32 is a level at which the water volume can be reduced without a sense of incongruity to the user, and needs to be set to a value at which the rise of the tapping temperature is quickened.
[0031]
FIG. 3 is a control flowchart of the water amount adjusting means 18 during hot water supply in the first embodiment. In FIG. 3, reference numeral 40 denotes a hot water supply load calculation of the hot water supply load detection means 20. Here, the difference between the water temperature Tw (° C.) detected by the water temperature detecting means 24 and the target temperature Tset (° C.) set by the temperature setting means 26 is multiplied by the flow rate W (L / min) detected by the flow rate detecting means 23. Then, this is multiplied by the conversion coefficient (60/860) to obtain the hot water supply load Qhw (kW). Although the calculation accuracy is deteriorated, the hot water supply load may be calculated by using the water temperature as a representative fixed value or the target temperature as a fixed value. According to this, the water temperature detecting means 24 and the temperature setting means 26 become unnecessary, and can be operated even at the time of failure.
[0032]
41 shows the setting of the heating amount Qhx (kW) in the heat amount detecting means 21. This reads the heating amount Qhx from the heating amount table 42 from the outside air temperature To (° C.) detected by the outside air temperature detector 27 and the water temperature Tw of the water temperature detector 24. The values in this table 42 are set in advance by experimentally determining the maximum heating amount under the combination conditions of the outside air temperature and the water temperature. This table may be a mathematical expression. Moreover, it is good also as a table | surface of the ternary heating amount of outside temperature, water temperature, and target temperature, the binary data which consists of another two elements out of outside temperature, water temperature, and target temperature may be sufficient. Although the system is worse, a single table with only one element may be used. This reduces the amount of experiment and reduces the memory.
[0033]
In the case where the hot water supply load Qhw exceeds the heating amount Qhx, the opening amount reduction setting for reducing the water amount by the water amount adjusting means 18 is performed in 44. On the other hand, if Qhw is smaller than Qhx in 43, the opening degree setting for returning the water amount by the water amount adjusting means 18 is performed in 45. The control here acts to reduce the amount of water so that the hot water supply load matches the heating amount when the hot water supply load exceeds the heating amount. 46 and 47 define an upper limit value for opening reduction, and 48 and 49 define a lower limit value for opening reduction. The lower limit is set to -70%. Even if the amount of water adjustment means 18 advances due to an abnormality or the like, a minimum opening of 30% is ensured so that it is fully closed and hot water supply is not stopped. ing.
[0034]
50 sets the opening degree of the water amount adjusting means 18. Here, the final opening setting X is obtained by adding the reduced opening Xd to the opening Xi at the start of hot water supply described in FIG. Then, at 51, the water amount adjusting means 18 is driven to the set opening degree.
[0035]
The operation and action of the above configuration will be described. When the faucet 17 is opened, tap water starts to flow from the water supply pipe 11. This is detected by the flow rate detection means 23, a signal is sent to the control means 19, and the compressor 2 is started.
[0036]
At this time, since the water amount adjusting means 18 is restricted to the initial opening, the amount of water is suppressed and the hot water is discharged. Therefore, the amount of heat exchange from the heat radiation means 3 to the water flow path 9 of the refrigerant circulation circuit 7 is suppressed, the temperature rise speed of the compressor 2 and the heat exchanger 10 is increased, and the temperature rise speed of the tapping temperature from the water flow path 9 is increased. Becomes faster. When the hot water temperature rises to (target temperature -5K) or higher, the initial opening degree throttled by the water amount adjusting means 18 is released, and the full opening is restored. At this time, since the pressure and temperature of the compressor 2 and the heat exchanger 10 are sufficiently increased, even if the amount of water is restored, the tapping temperature can be reached without decreasing.
[0037]
The heating control means 22 controls the frequency of the compressor 2 based on the deviation between the tapping temperature and the target temperature. The high-temperature and high-pressure refrigerant gas discharged from the compressor 2 flows into the radiator 3 and heats the water flowing through the water flow path 9. The heated water is discharged from the hot water supply terminal 12 through the hot water supply circuit 13. On the other hand, the refrigerant cooled by the radiator 3 is decompressed by the decompression means 4 and flows into the heat absorber 5, where it absorbs natural energy such as atmospheric heat and solar heat to evaporate and returns to the compressor 2. Accordingly, the hot water is detected, and the high-temperature and high-pressure refrigerant gas from the compressor 1 immediately flows into the radiator 3 to heat the water, and the hot water can be used from the hot water supply terminal 12 as it is.
[0038]
The heating control means 22 during hot water supply calculates the frequency using the known PID control from the deviation between the tapping temperature and the target temperature. That is, feedback control of the tapping temperature is performed. The proportional constant, integral coefficient, and differential coefficient, which are control constants here, need to be set in advance to optimum values for achieving both control response and stability. The feedback control may be PI control, P control, fuzzy or neuro control.
[0039]
When hot water supply at a large flow rate such as hot water supply at two or more places occurs during hot water supply and a hot water supply load exceeding the maximum heating amount in the heat exchanger 10 is generated, the control means 19 moves the water amount adjusting means 18 in the throttle direction. Since it is driven and the amount of water is reduced until the hot water supply load substantially coincides with the maximum heating amount, it is possible to maintain the target temperature without drastically lowering the hot water temperature.
[0040]
Even when the flow rate changes from a large flow rate to a normal flow rate, if the hot water supply load falls below the maximum heating amount, the throttling at the water amount adjusting means 18 changes from a decrease in the water amount to a return to the water amount and returns to the fully open operation, so that the user does not feel uncomfortable. Hot water operation is possible.
[0041]
In the first embodiment, the refrigerant circulation circuit is a supercritical refrigerant circulation circuit in which the pressure of the refrigerant is equal to or higher than the critical pressure. However, a refrigerant circulation circuit having a general critical pressure or lower may be used.
[0042]
(Example 2)
FIG. 4 is a control flowchart of the water amount adjusting means 18 at the time of hot water supply of the heat pump hot water supply apparatus according to Embodiment 2 of the present invention. In addition, the thing of the same structure as the hot water supply apparatus of Example 1 gives the same code | symbol, and abbreviate | omits description. In FIG. 4, the difference from the configuration of the first embodiment is that the water amount adjusting means 18 is controlled by a set value of 55 water amount upper limit. 55, the upper limit WL (L / min) of the water amount is calculated from the maximum heating amount Qhx (kW) obtained by 41, the target temperature Tset (° C.), and the water temperature Tw (° C.). Then, it is determined at 56 whether or not the water amount W (L / min) detected by the flow rate detection means 23 exceeds the upper limit WL of the water amount, and if it exceeds 44, the opening for reducing the water amount by the water amount adjustment means 18 at 44. Make reduction settings. On the other hand, if it does not exceed, an opening increase setting for returning the water amount by the water amount adjusting means 18 is performed at 45.
[0043]
As described above, in Example 2, the upper limit of the amount of water is set from the maximum amount of heating, and control is performed so that the detected value of the amount of water does not exceed this upper limit.
[0044]
Example 3
FIG. 5 is a control flowchart of the water amount adjusting means 18 at the time of hot water supply of the heat pump hot water supply apparatus according to Embodiment 3 of the present invention. In addition, the thing of the same structure as the hot water supply apparatus of Example 1 gives the same code | symbol, and abbreviate | omits description. In FIG. 5, the difference from the configuration of the first embodiment is that a second target value that is 5K lower than the target temperature set by the temperature setting means 26 is set, and the hot water temperature is set to the second temperature after 3 minutes from the start of hot water supply. When the heating control means 22 sets the frequency of the compressor 2 to the upper limit, the amount of water is reduced. Specifically, the control is as follows.
[0045]
In 60, the frequency of the compressor 2 of the heating control means 22 is set. That is, the frequency F is calculated from the deviation between the hot water temperature Thw and the target temperature Tset using known PID control.
[0046]
61 determines whether 3 minutes have passed since the start of hot water supply. If it is less than 3 minutes, the opening reduction setting for reducing the amount of water is set to 0% at 62, and the decrease in the amount of water is prohibited. If it is determined in 61 that 3 minutes or more have elapsed, the process proceeds to 63.
[0047]
If the control frequency F of the compressor 2 is equal to or higher than the upper limit value Fmax and the tapping temperature Thw is less than the target temperature Tset-3K, the opening amount reduction setting for reducing the water amount is performed by the water amount adjusting means 18 in 44. On the other hand, if the condition of 63 is not satisfied, the opening amount increase setting for returning the water amount by the water amount adjusting means 18 is performed at 45.
[0048]
3 minutes from the start of 61 hot water supply sets the time until the capacity and temperature of the entire system rise, and this value varies depending on the system conditions.
[0049]
The determination in 63 determines whether or not the maximum heating amount has been reached by the frequency F, and determines whether or not the capacity is insufficient by the tapping temperature Thw. And by these both, it determines with having reached the maximum heating amount and having fallen in capacity. In the third embodiment, the determination accuracy is improved by determining both the frequency F and the tapping temperature Thw. However, even if each determination is made independently, it is possible to determine a lack of capability with sufficient accuracy.
[0050]
In the above embodiments 1 to 3, a hot water storage device having no hot water storage tank or heat storage material has been described, but if it is configured to supply hot water heated by a heat pump during hot water supply directly to the hot water supply terminal, The same effect can be obtained by having a hot water storage tank in parallel with the heat exchanger, having a hot water storage tank in series with the heat exchanger, and further having a heat storage material in the water circuit or refrigerant circuit. can get.
[0051]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a heat pump hot water supply apparatus with good responsiveness and stability of hot water supply control.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a heat pump hot water supply apparatus in Embodiment 1 of the present invention. FIG. 2 is a control flowchart of water amount adjusting means at the start of hot water supply in Embodiment 1 of the present invention. FIG. 4 is a control flowchart of the water amount adjusting means during hot water supply in Embodiment 2 of the present invention. FIG. 5 is a control flowchart of the water amount adjusting means during hot water supply in Embodiment 3 of the present invention. 6] Configuration diagram of conventional heat pump water heater [Explanation of symbols]
DESCRIPTION OF SYMBOLS 2 Compressor 3 Radiator 4 Pressure reduction means 5 Heat absorber 7 Refrigerant circulation circuit 9 Water flow path 10 Heat exchanger 11 Water supply pipe 12 Hot water supply terminal 13 Hot water supply circuit 18 Water quantity adjustment means 20 Hot water supply load detection means 21 Heat quantity detection means 22 Heating control means 23 Flow rate detection means 24 Water temperature detection means 25 Hot water temperature detection means 26 Temperature setting means 27 Outside air temperature detection means

Claims

A refrigerant circulation circuit including a compressor, a radiator, a decompression unit, and a heat absorber; a heat exchanger including a water channel that exchanges heat with the radiator; a water supply pipe that supplies tap water to the water channel; A hot water supply circuit connected so as to pass water from the water flow path to the hot water supply terminal, water amount adjusting means for adjusting the amount of water in the water flow path, and tap water heated by the heat exchanger via the hot water supply circuit A route for directly discharging hot water from the hot water supply terminal, and a water amount adjusting means for adjusting the amount of water in the water flow path when the hot water supply load exceeds the maximum capacity as the refrigerant circulation circuit, and a predetermined time after the hot water supply is stopped. When the predetermined time has elapsed, when the hot water supply is started , the water amount adjusting means is set to an initial opening that is previously reduced by a predetermined amount, and when the predetermined time has not elapsed, the water amount adjusting means is previously set. Set the initial opening to a predetermined amount. The heat pump water heater, characterized in that there is no.

A hot water supply load detecting means for obtaining a hot water supply load which is the amount of hot water supplied to the hot water supply circuit, and a heat amount detecting means for detecting the amount of heating in the heat exchanger are provided, and the value of the hot water supply load detecting means sets the value of the heat quantity detecting means. The heat pump hot-water supply apparatus of Claim 1 which reduces a water quantity by a water quantity adjustment means, when exceeding.

A water temperature detecting means for detecting a water temperature of the water supply pipe, a temperature setting means for setting a target temperature of the hot water supply, and a flow rate detecting means for detecting the flow rate of the hot water supply circuit are provided. The heat pump hot water supply apparatus according to claim 2, wherein a hot water supply load is obtained from at least one of values of the setting means and the flow rate detection means.

An outside air temperature detecting means for detecting the outside air temperature, a water temperature detecting means for detecting the feed water temperature of the water supply pipe, and a temperature setting means for setting the target temperature of the hot water supply are provided, and the heat quantity detecting means is the outside air temperature detecting means and the water temperature detecting means. The heat pump hot-water supply apparatus of Claim 2 or 3 which calculates | requires the heating amount in a heat exchanger from at least one of the value of a means and a temperature setting means.

The heat pump hot water supply apparatus according to any one of claims 2 to 4, wherein the water amount reduction amount by the water amount adjusting unit decreases the water amount so that the value of the hot water supply load detecting unit coincides with the value of the heat amount detecting unit.