JP3738299B2

JP3738299B2 - Heat pump type heat supply device

Info

Publication number: JP3738299B2
Application number: JP2000141338A
Authority: JP
Inventors: 浩二伊藤; 昭治菊地; 満小松; 良和石木
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2000-05-15
Filing date: 2000-05-15
Publication date: 2006-01-25
Anticipated expiration: 2020-05-15
Also published as: JP2001324234A

Description

【０００１】
【発明の属する技術分野】
本発明はヒートポンプ式熱供給装置に係り、特に、冷水および温水を空気調和装置等に切り換えて供給することのできるヒートポンプ式熱供給装置に関する。
【０００２】
【従来の技術】
ヒートポンプ式熱供給装置には空気側熱交換器、減圧器および水側熱交換器が設けられ、空気側熱交換器は冷媒と外気との間で熱交換を行い、水側熱交換器は冷媒と内部を通流する水との間で熱交換を行うようになっている。そして、圧縮機からの冷媒を室外側熱交換器、減圧器および室内側熱交換器の順に流すと、水側熱交換器内を通流する水は冷却され冷水として供給される。また、逆に圧縮機からの冷媒を室内側熱交換器、減圧器および室外側熱交換器の順に流すと、水側熱交換器内を通流する水は加温され温水として供給される。冷水にするか温水にするかは、圧縮機の吐出側配管に取り付けられた四方切換弁を切り換えることにより行われる。
【０００３】
ところで、四方切換弁を切り換えた際に、四方切換弁が正常に切り換わらないで弁体が中間位置で止まったりしていると、装置の運転を正常に行うことができず、運転を停止せざるを得なくなる。
【０００４】
空気調和機についての技術であるが、例えば特開平８−１２８７４９号公報には、四方切換弁を切り換えた際に、その切換前後の配管温度を検出して切換前後の温度差を見ることにより、四方切換弁が正常に切り換わったか否かを判定することが提案されている。しかし、四方切換弁が正常に切り換わったか否かを単に判定するだけでは、正常に切り換わっていない場合は、正常な運転を継続できないことになり、結局、空気調和装置の運転を停止させなければならない。
【０００５】
そこで、特開平５−３２２３５５号公報には、四方切換弁の弁体が中間位置で止まるのを防止するようにした空気調和機が提案されている。この空気調和機においては、四方切換弁は圧縮機の吐出側と吸込側との圧力差を利用して冷媒の流れを変えるものであり、また圧縮機の吐出側と吸込側間には四方切換弁をバイパスしてバイパス回路が設けられている。そして、バイパス回路には開閉弁が取り付けられており、暖房運転時に圧縮機の起動と同時にこの開閉弁を開けると、四方切換弁にかかる圧力差が小さくなって四方切換弁の弁体が中間位置に止まってしまうので、前記開閉弁を１０秒間遅らせてから開けるようにして、弁体が中間位置に止まるのを防止している。
【０００６】
【発明が解決しようとする課題】
ここで、上記のように開閉弁を１０秒間遅らせてから開けることをヒートポンプ式熱供給装置に適用しても、四方切換弁の動作不良を完全に無くすことはできない。すなわち、起動時には圧縮機の吐出側と吸込側との圧力差に大きなバラツキがあるので、開閉弁を１０秒間遅らせてから開けるようにしても、四方切換弁が正常に動作するとは限らず、中間位置に止まってしまう可能性が大きい。
【０００７】
また、上述のように圧縮機の吐出側と吸込側との圧力差に大きなバラツキがあると、四方切換弁の切換時に弁体に大きな力が加わって、弁体が割れてしまう恐れもある。
【０００８】
本発明の目的は、四方切換弁を適正に切り換えることのできるヒートポンプ式熱供給装置を提供することにある。
【０００９】
【課題を解決するための手段】
上記目的を達成するために、本発明は、圧縮機、第１の熱交換器、減圧器、第２の熱交換器、及び四方切換弁が順次接続された冷凍サイクルを備え、第１の熱交換器は該熱交換器外側を流れる空気と冷凍サイクル内を循環する冷媒との間で熱交換を行い、第２の熱交換器は該熱交換器内を通流する流体と前記冷媒との間で熱交換を行って、四方切換弁を切り換えて、前記冷媒を第１の熱交換器、減圧器および第２の熱交換器の順に流したときに前記流体が冷却されて供給され、四方切換弁を逆に切り換えて、前記冷媒を第２の熱交換器、減圧器および第１の熱交換器の順に流したときに前記流体が加温されて供給されるヒ−トポンプ式熱供給装置において、圧縮機の吐出側圧力と吸込側圧力を検出する圧力検出手段と、圧力検出手段から検出結果を取り込んで圧縮機の吐出側圧力と吸込側圧力との差圧を演算するとともに、四方切換弁を切り換える際に、前記差圧が予め設定された適正範囲に入っているか否かを判定し、適正範囲外の場合は、圧縮機の吐出量を変化させ前記差圧が適正値範囲内に入ってから四方切換弁の切換を行う制御手段と、を備えたことを特徴としている。
【００１０】
上記構成によれば、四方切換弁を切り換える際に、制御手段は、圧縮機の吐出圧力と吸込側圧力との差圧が予め設定された適正範囲に入っているか否かを判定し、適正範囲に入っていれば直ちに四方切換弁の切換を行うが、適正範囲外の場合、圧縮機の吐出量を変化させて差圧が適正値範囲内に入ってから、四方切換弁の切換を行う。これにより、四方切換弁に大きな圧力差が加わるのを回避できるので、弁体に割れや損傷が発生するのを防ぐことができる。さらに、圧力差が小さすぎて四方切換弁の弁体が中間位置で止まってしまうことも防ぐことができる。
【００１１】
実際に、制御手段は、適正範囲の上限値を越えている場合は圧縮機の吐出量を減少させ、差圧が適正範囲の下限値未満の場合は圧縮機の吐出量を増加させて、差圧が適正値範囲内に入ってから四方切換弁の切換を行うよう制御する。
【００１２】
適正範囲は、差圧に応じて定まる四方切換弁の切換回数の寿命特性から決定される。
【００１３】
また、本発明では、圧縮機の吐出量を減少もしくは増加させても前記差圧が適正範囲内に入らない場合は、圧縮機を停止させるとともに警報表示するよう構成されている。この場合、差圧が適正範囲に入ったら、圧縮機を再起動するようにする。
【００１４】
さらに、四方切換弁を切り換えた後に、圧力検出手段から検出結果を取り込んで圧縮機の吐出側圧力と吸込側圧力との差圧を演算し、その差圧が異常値の場合は、圧縮機を停止させるよう構成することもできる。この場合、圧縮機を停止させて所定時間経過後に、圧縮機を再起動させるとともに前記差圧を演算し、その差圧が異常値の場合は圧縮機を停止させる。また、圧縮機の起動と停止を所定回数繰り返したとき、警報表示を行うようにする。
【００１５】
【発明の実施の形態】
以下、本発明の実施の形態を図面に従って説明する。
（実施の形態１）
図１は本発明に係るヒ−トポンプ式熱供給装置の構成図である。図に示すように、圧縮機１、四方切換弁２、第１の熱交換器３、膨張弁４、第２の熱交換器５、および四方切換弁２が順次接続されて冷凍サイクルが形成されている。すなわち、圧縮機１の吐出側は冷媒流路Ｌ１を介して四方切換弁２に接続され、四方切換弁２は冷媒流路Ｌ２を介して第１の熱交換器３に、第１の熱交換器３は冷媒流路Ｌ３を介して膨張弁４にそれぞれ接続されている。また、膨張弁４は冷媒流路Ｌ４を介して第２の熱交換器５に、第２の熱交換器５は冷媒流路Ｌ５を介して四方切換弁２に、四方切換弁２は冷媒流路Ｌ６を介して圧縮機１の吸込側にそれぞれ接続されている。
【００１６】
第１の熱交換器３は熱源側の熱交換器で、冷却ファン６によって空冷される。また第２の熱交換器５は利用側の熱交換器で、流入管５Ａおよび流出管５Ｂが取り付けられ、流入管５Ａから流入した水が内部を通流し、その後、流出管５Ｂから流出する。
【００１７】
上記冷凍サイクル内は冷媒が循環し、第２の熱交換器５内を通流する水を冷却する運転（以下、冷水供給運転という）時には冷媒は図の実線矢印のように流れ、加温する運転（以下、温水供給運転という）時には冷媒は図の破線矢印のように流れる。また四方切換弁２は、冷媒の流れる流路が冷水供給運転時には実線のように、温水供給運転時には破線のようにそれぞれ切り換えられる。
【００１８】
また、冷媒流路Ｌ１には圧縮機１の吐出側冷媒圧力を検出する圧力センサ７が、冷媒流路Ｌ６には圧縮機１の吸込側冷媒圧力を検出する圧力センサ８がそれぞれ設けられ、これら圧力センサ７，８での検出信号が入力される制御装置９が設置されている。
【００１９】
上記構成において、冷水供給運転時には、圧縮機１で圧縮された高温高圧のガス冷媒は、冷媒流路Ｌ１を介して四方切換弁２に導かれ、この四方切換弁２を実線の流路に沿って流れた後、冷媒流路Ｌ２を介して第１の熱交換器３に導かれる。第１の熱交換器３において、高温高圧のガス冷媒は冷却ファン６によって送風される空気と熱交換して凝縮され、高温高圧の液冷媒となる。その高温高圧の液冷媒は冷媒流路Ｌ３を介して膨張弁４に導かれ、この膨張弁４によって減圧されて低温低圧の二相冷媒となり、さらに冷媒流路Ｌ４を介して第２の熱交換器５に導かれる。そして第２の熱交換器５において、低温低圧の二相冷媒は、第２の熱交換器５内を通流する水と熱交換して、その水を冷却する。これにより、第２の熱交換器５からは冷水を得ることができる。
【００２０】
第２の熱交換器５で水と熱交換した低温低圧の二相冷媒は蒸発して低温低圧のガス冷媒となり、冷媒流路Ｌ５を介して四方切換弁２に導かれ、この四方切換弁２を通過後に、冷媒流路Ｌ６を介して圧縮機１に戻され、圧縮機１で再び圧縮される。
【００２１】
温水供給運転時には、圧縮機１で圧縮された高温高圧のガス冷媒は、冷媒流路Ｌ１を介して四方切換弁２に導かれ、この四方切換弁２を破線の流路に沿って流れた後、冷媒流路Ｌ５を介して第２の熱交換器５に導かれる。第２の熱交換器５において、高温高圧のガス冷媒は第２の熱交換器５内を通流する水と熱交換して、その水を加温する。これにより、第２の熱交換器５からは温水を得ることができる。
【００２２】
第２の熱交換器５で水と熱交換した高温高圧のガス冷媒は凝縮して高温高圧の液冷媒となる。その高温高圧の液冷媒は冷媒流路Ｌ４を介して膨張弁４に導かれ、この膨張弁４によって減圧されて低温低圧の二相冷媒となり、さらに冷媒流路Ｌ３を介して第１の熱交換器３に導かれる。第１の熱交換器３において、低温低圧の二相冷媒は冷却ファン６によって送風される空気と熱交換して蒸発し、低温低圧のガス冷媒となる。そして、その低温低圧のガス冷媒は冷媒流路Ｌ２を介して四方切換弁２に導かれ、この四方切換弁２を通過後、冷媒流路Ｌ６を介して圧縮機１に戻され、圧縮機１で再び圧縮される。
【００２３】
図２および図３は四方切換弁２の構成とその駆動機構で、図２は冷水供給運転時の状態を、図３は温水供給運転時の状態をそれぞれ示している。
図２および図３に示すように、四方切換弁２には流路接続部２Ａ，２Ｂ，２Ｃ，２Ｄが設けられ、流路接続部２Ａは冷媒流路Ｌ１に、流路接続部２Ｂは冷媒流路Ｌ５に、流路接続部２Ｃは冷媒流路Ｌ６に、流路接続部２Ｄは冷媒流路Ｌ２にそれぞれ接続されている。また、四方切換弁２には、その内部に断面半円状の弁体２Ｅが移動自在に設けられ、この弁体２Ｅは、その両側に配置されたピストン２Ｆ，２Ｇに連結され、ピストン２Ｆ，２Ｇが四方切換弁２の内部を図の左右方向に移動すると、それに連動して左右方向に移動する。これによって、図２のように流路接続部２Ａを流路接続部２Ｄに、流路接続部２Ｃを流路接続部２Ｂに接続することができ、また、図３のように流路接続部２Ａを流路接続部２Ｂに、流路接続部２Ｃを流路接続部２Ｄに接続することができる。
【００２４】
また、流路切換制御弁１０が設けられ、この流路切換制御弁１０を切換操作して流路接続部２Ａ内の圧力を四方切換弁２の圧力室２Ｈもしくは圧力室２Ｉに、または流路接続部２Ｃ内の圧力を圧力室２Ｈもしくは圧力室２Ｉに伝達することにより、ピストン２Ｆ，２Ｇは四方切換弁２の内部を図の左右方向に移動する。
【００２５】
冷水供給運転時には、流路切換制御弁１０が図２のように切り換えられる。流路接続部２Ａには圧縮機１によって圧縮された高温高圧のガス冷媒が、流路接続部２Ｃには圧縮機１によって吸引される低温低圧のガス冷媒が流れているので、圧力室２Ｉは高圧側に、圧力室２Ｈは低圧側となって、ピストン２Ｆ，２Ｇは図の左方向に押され弁体２Ｅも同方向に移動する。これによって、高温高圧のガス冷媒は流路接続部２Ａから流路接続部２Ｄへと流れ、低温低圧のガス冷媒は流路接続部２Ｂから流路接続部２Ｃへと流れる。
【００２６】
温水供給運転時には、流路切換制御弁１０が図３のように切り換えられる。この場合は、圧力室２Ｉは低圧側に、圧力室２Ｈは高圧側となって、ピストン２Ｆ，２Ｇは図の右方向に押され弁体２Ｅも同方向に移動する。これによって、高温高圧のガス冷媒は流路接続部２Ａから流路接続部２Ｂへと流れ、低温低圧のガス冷媒は流路接続部２Ｄから流路接続部２Ｃへと流れる。
【００２７】
図４は、本実施の形態におけるヒートポンプ式熱供給装置の動作フロ−チャ−トを示している。圧縮機１は吐出量を５０％、７５％、１００％と段階的に切り換える機能を備えたものである。ここで、冷凍サイクルを冷水供給運転から温水供給運転、もしくは温水供給運転から冷水供給運転に切り換える際に、圧縮機１の吐出側圧力Ｐｄを圧力センサ７により検出し、吸込側圧力Ｐｓを圧力センサ８により検出する。圧力センサ７，８での検出信号は制御装置９に入力され、制御装置９は、入力された検出信号に基づいて差圧ΔＰ＝Ｐｄ−Ｐｓを演算する。そして、制御装置９は差圧ΔＰが適正範囲に入っているか否か判定し、差圧ΔＰが０.０７５ＭＰａを越えている場合は、圧縮機１の吐出量を７５％に減少させる。その結果、熱交換器３，５の伝熱面積に余裕ができ、吐出側圧力Ｐｄが低下し、吸込側圧力Ｐｓが上昇して、差圧ΔＰは小さくなる。そして所定時間経過後、再度、差圧ΔＰを演算し、０.０７５ＭＰａ以下であれば四方切換弁２を切り換える。まだ０.０７５ＭＰａを越えている場合は圧縮機１の吐出量を５０％に減少させて差圧ΔＰを小さくし、０.０７５ＭＰａ以下になれば四方切換弁２を切り換える。
【００２８】
一方、差圧ΔＰが０.０３５ＭＰａ未満の場合は、圧縮機１の吐出量を７５％、１００％と増加させることにより差圧ΔＰを増加させ、０.０３５ＭＰａ以上となれば四方切換弁２を切り換える。
【００２９】
なお、圧縮機１の吐出量を減少もしくは増加させても、差圧ΔＰが０.０３５ＭＰａ≦ΔＰ≦０.０７５ＭＰａの範囲内に入らない場合は、圧縮機１を停止させるとともに警報表示する。
【００３０】
また、四方切換弁２を切り換えた後の差圧ΔＰを演算し、その差圧ΔＰが異常値、例えば０〜０.０２ＭＰａの場合は、四方切換弁２の弁体が中間位置に停止、もしくは弁体の切り換え不良と判断し、冷凍サイクルの運転を停止する。
【００３１】
その停止から所定時間経ったら、再運転の再開を行い、差圧ΔＰが０.０２ＭＰａを越えていれば運転を継続し、０〜０.０２ＭＰａの場合は運転を停止させる。そして、運転の再開・停止を所定回数を繰り返したときは、四方切換弁２に異常があるとの警報表示を行い、冷凍サイクル運転を完全停止させる。
【００３２】
上記のように、本実施の形態では、差圧ΔＰが０.０３５ＭＰａ≦ΔＰ≦０.０７５ＭＰａの範囲内で、四方切換弁２を切り換えるよう圧縮機１の吐出量を調整するとともに、四方切換弁２を切り換えた後の差圧ΔＰが異常値の場合、運転を停止させ、所定回数再運転をした後、警報表示して運転を停止させる。
【００３３】
図５は、四方切換弁の動作時差圧ΔＰと切換回数による寿命との関係を示している。図から分かるように、差圧ΔＰが大きければ、四方切換弁は切換回数が小さくても故障しやすく、寿命が低下する。逆に、差圧ΔＰが小さければ、四方切換弁は切換回数が大きくても故障しにくく、長寿命化となる。そこで、本実施の形態では、四方切換弁の機械的、強度的寿命特定を鑑み、適正な差圧範囲で四方切換弁の切換を行うよう制御する。
【００３４】
本実施の形態によれば、四方切換弁２に加わる差圧を制御することにより、四方切換弁２を切り換える際に弁体には適正な差圧が加えられるため、弁体の割れ、破損等を防止することができ、四方切換弁２の長寿命化を図ることができる。
【００３５】
また、四方切換弁２を切り換えた後の差圧を求めることにより、四方切換弁２の弁体が中間位置に停止しているか否かを検知することができ、もし弁体が中間位置に停止していれば運転を停止させ、所定時間経ってから運転を自動的に再開することで冷凍サイクルが保護され、システム全体の信頼性向上につながる。
【００３６】
なお、本実施の形態では差圧ΔＰが０.０３５ＭＰａ≦ΔＰ≦０.０７５ＭＰａの範囲内で四方切換弁２の切換を行うようにしたが、どの位の切換回数を寿命とするかによって差圧ΔＰを変更することができる。
【００３７】
また、第２の熱交換器５内を通流する流体は水に限らず、他の流体であってもよい。
【００３８】
（実施の形態２）
図６は、本発明の実施の形態２を示している。本実施の形態では、圧縮機１は所定の吐出量を連続的に変えることができるように構成されたものである。他の構成は、実施の形態１と同じである。すなわち、冷凍サイクルの構成は図１に示したものと同じであり、また四方切換弁２の構成も図２および図３に示したものと同じである。
【００３９】
本実施の形態では、制御装置９は四方切換弁２を切り換える差圧ΔＰを演算し、差圧ΔＰが０.０７５ＭＰａを越えている場合は、圧縮機１の吐出量を所定量、例えば５％減少させる（なお、所定量は任意の値である）。そして、所定時間経過後に、再度、差圧ΔＰを演算し、０.０７５ＭＰａを越えていれば、同様に吐出量を５％減少させ、差圧ΔＰが０.０７５ＭＰａ以下となるよう調整する。
【００４０】
また、差圧ΔＰが０.０３５ＭＰａ未満の場合も、同様に圧縮機１の吐出量を所定量増加させ、差圧ΔＰが０.０３５ＭＰａ以上となれば四方切換弁２を切り換える。
【００４１】
本実施の形態によれば、四方切換弁１に加わる差圧を検知し、圧縮機１の吐出量を所定量変化させることにより、実施の形態１と同様に、四方切換弁２の弁体の割れや破損の防止、並びに弁体が中間位置に停止するのを防止できる。さらに、本実施の形態では、圧縮機１からの吐出量が所定量で連続的に制御されるので、減容遅れによる必要以上の容量制限を加える必要がない。つまり、冷水または温水を供給する能力低下を最小限に抑えることができる。
【００４２】
（実施の形態３）
次に、図７を用いて実施の形態３について説明する。圧縮機１は、実施の形態１の場合と同様、吐出量を５０％、７５％、１００％と段階的に切り換える機能を備えたものである。ここで、温水供給運転から除霜運転に切り換える際に、圧縮機１の吐出側圧力Ｐｄを圧力センサ７により検出し、吸込側圧力Ｐｓを圧力センサ８により検出する。圧力センサ７，８での検出信号は制御装置９に入力され、制御装置９は差圧ΔＰ＝Ｐｄ−Ｐｓを演算する。そして、制御装置９は差圧ΔＰがΔＰmax以下であるか否か判定し、ΔＰmaxを越えている場合は、圧縮機１の吐出量を変化させる（例えば、吐出量を７５％に減少させる）。ある一定時間経過後、再度、差圧ΔＰを演算し、ΔＰmax以下であれば四方切換弁２を切り換える。まだ、ΔＰmaxを越えていれば、圧縮機１の吐出量を更に変化させる（例えば、吐出量を５０％に減少させる）。そして、ΔＰmax以下になれば四方切換弁２を切り換える。
【００４３】
また、四方切換弁２を切り換えた後の差圧ΔＰを演算し、その差圧ΔＰが異常値ΔＰmin未満の場合は、四方切換弁２の弁体が中間位置に停止、もしくは弁体の切り換え不良と判断されるので、冷凍サイクルの運転（すなわち、圧縮機１の運転）を停止する。
【００４４】
その停止から所定時間経ったら、再運転の再開を行い、差圧ΔＰがΔＰmin以上であれば運転を継続し、ΔＰmin未満であれば運転を停止させる。そして、運転の再開・停止を所定回数を繰り返したとき、四方切換弁２に異常があるとの警報表示を行い、冷凍サイクル運転を完全停止させる。なお、ΔＰmaxおよびΔＰminの具体例は図５の示してある。
【００４５】
上記のように本実施の形態では、差圧ΔＰをΔＰmin〜ΔＰmaxの範囲内で四方切換弁を切り換えるよう圧縮機の吐出量を調整し、差圧ΔＰが異常値の場合、運転を停止させ、所定回数再運転をした後、警報表示して運転を停止させる。
本実施の形態によれば、実施の形態１と同様な効果を得ることができる。
【００４６】
（実施の形態４）
次に、図８を用いて実施の形態４について説明する。圧縮機１は、実施の形態２と同様に、所定の吐出量を連続的に変えることのできるようになっている。
【００４７】
本実施の形態では、制御装置９は四方切換弁２を切り換える差圧ΔＰを演算し、差圧ΔＰがΔＰmaxを越えている場合は、圧縮機１の吐出量を所定量に変化させ、例えば５％減少させる。そして、所定時間経過後に、再度、差圧ΔＰを演算し、ΔＰmax以下であれば四方切換弁２を切り換え、ΔＰmaxを越えていれば圧縮機１の吐出量を所定量変化（減少）させて差圧ΔＰを小さくし、ΔＰmax以下になるよう繰り返し調整する。
本実施の形態によれば、実施の形態２と同様な効果を得ることができる。
【００４８】
【発明の効果】
以上説明したように、本発明によれば、四方切換弁を切り換える差圧を演算し、適正な差圧状態にて四方切換弁を切り換えることにより、弁体の割れや破損を防止でき、また弁体が中間位置に停止することも防止できる。その結果、四方切換弁の信頼性が向上して、長寿命化を図ることができる。
【図面の簡単な説明】
【図１】本発明に係るヒートポンプ式熱供給装置の構成図である。
【図２】四方切換弁の冷水供給運転時の状態を示した図である。
【図３】四方切換弁の温水供給運転時の状態を示した図である。
【図４】本発明の実施の形態１による動作フロ−チャ−トである。
【図５】四方切換弁の寿命線図である。
【図６】本発明の実施の形態２による動作フロ−チャ−トである。
【図７】本発明の実施の形態３による動作フロ−チャ−トである。
【図８】本発明の実施の形態４による動作フロ−チャ−トである。
【符号の説明】
１圧縮機
２四方切換弁
３第１の熱交換器
４膨張弁
５第２の熱交換器
６冷却ファン
７，８圧力センサ（圧力検出手段）
９制御装置（制御手段）
１０流路切換制御弁[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat pump heat supply device, and more particularly, to a heat pump heat supply device that can supply cold water and hot water by switching to an air conditioner or the like.
[0002]
[Prior art]
The heat pump heat supply device is provided with an air-side heat exchanger, a decompressor, and a water-side heat exchanger. The air-side heat exchanger exchanges heat between the refrigerant and the outside air, and the water-side heat exchanger is a refrigerant. Heat exchange with the water flowing through the inside. And if the refrigerant | coolant from a compressor is flowed in order of an outdoor side heat exchanger, a pressure reduction device, and an indoor side heat exchanger, the water which flows through the inside of a water side heat exchanger will be cooled and supplied as cold water. Conversely, when the refrigerant from the compressor is flowed in the order of the indoor heat exchanger, the decompressor, and the outdoor heat exchanger, the water flowing through the water heat exchanger is heated and supplied as hot water. Whether to use cold water or hot water is performed by switching a four-way switching valve attached to the discharge side piping of the compressor.
[0003]
By the way, when the four-way switching valve is switched, if the four-way switching valve does not switch normally and the valve body stops at the intermediate position, the operation of the device cannot be performed normally and the operation is stopped. It must be.
[0004]
For example, in Japanese Patent Application Laid-Open No. 8-128749, when a four-way switching valve is switched, a pipe temperature before and after the switching is detected and a temperature difference before and after the switching is observed. It has been proposed to determine whether the four-way switching valve has been switched normally. However, simply determining whether or not the four-way selector valve has been switched normally will not allow normal operation to continue if it has not switched normally, and eventually the operation of the air conditioner must be stopped. I must.
[0005]
Japanese Patent Laid-Open No. 5-322355 proposes an air conditioner that prevents the valve body of the four-way switching valve from stopping at an intermediate position. In this air conditioner, the four-way switching valve changes the refrigerant flow by utilizing the pressure difference between the discharge side and the suction side of the compressor, and switches between the discharge side and the suction side of the compressor. A bypass circuit is provided to bypass the valve. An opening / closing valve is attached to the bypass circuit. When the opening / closing valve is opened simultaneously with the start of the compressor during heating operation, the pressure difference applied to the four-way switching valve is reduced and the valve body of the four-way switching valve is in the intermediate position. Therefore, the valve body is prevented from being stopped at the intermediate position by opening the on-off valve after being delayed for 10 seconds.
[0006]
[Problems to be solved by the invention]
Here, even if the opening of the on-off valve is delayed for 10 seconds as described above and applied to the heat pump heat supply device, the malfunction of the four-way switching valve cannot be completely eliminated. That is, since there is a large variation in the pressure difference between the discharge side and the suction side of the compressor at the time of starting, even if the on-off valve is opened after being delayed for 10 seconds, the four-way switching valve does not always operate normally, There is a high possibility of stopping in position.
[0007]
Further, as described above, if there is a large variation in the pressure difference between the discharge side and the suction side of the compressor, a large force is applied to the valve body when the four-way switching valve is switched, and the valve body may be broken.
[0008]
An object of the present invention is to provide a heat pump type heat supply device capable of appropriately switching a four-way switching valve.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present invention comprises a refrigeration cycle in which a compressor, a first heat exchanger, a decompressor, a second heat exchanger, and a four-way switching valve are sequentially connected, and the first heat The exchanger exchanges heat between the air flowing outside the heat exchanger and the refrigerant circulating in the refrigeration cycle, and the second heat exchanger exchanges the fluid flowing through the heat exchanger with the refrigerant. The fluid is cooled and supplied when the refrigerant flows in the order of the first heat exchanger, the decompressor, and the second heat exchanger. A heat pump type heat supply device in which the fluid is heated and supplied when the switching valve is switched in the reverse direction and the refrigerant flows in the order of the second heat exchanger, the decompressor, and the first heat exchanger. Pressure detection means for detecting the discharge side pressure and suction side pressure of the compressor, and detection from the pressure detection means The result is taken in and the differential pressure between the discharge side pressure and the suction side pressure of the compressor is calculated, and when the four-way switching valve is switched, it is determined whether or not the differential pressure is within a preset appropriate range. In the case where it is out of the proper range, there is provided control means for changing the discharge amount of the compressor and switching the four-way switching valve after the differential pressure falls within the proper value range.
[0010]
According to the above configuration, when switching the four-way switching valve, the control means determines whether or not the differential pressure between the discharge pressure of the compressor and the suction side pressure is within a preset proper range, and the proper range. If it is, the four-way switching valve is immediately switched. If it is out of the proper range, the discharge amount of the compressor is changed and the differential pressure enters the proper value range, and then the four-way switching valve is switched. Thereby, since it can avoid that a big pressure difference is added to a four-way selector valve, it can prevent that a crack and damage generate | occur | produce in a valve body. Furthermore, it is possible to prevent the pressure difference from being too small and stopping the valve body of the four-way switching valve at the intermediate position.
[0011]
Actually, the control means decreases the discharge rate of the compressor if the upper limit value of the appropriate range is exceeded, and increases the discharge rate of the compressor if the differential pressure is less than the lower limit value of the proper range. Control is performed so that the four-way switching valve is switched after the pressure falls within the appropriate value range.
[0012]
The appropriate range is determined from the life characteristics of the number of switching times of the four-way switching valve determined according to the differential pressure.
[0013]
Further, in the present invention, when the differential pressure does not fall within the proper range even if the discharge amount of the compressor is decreased or increased, the compressor is stopped and an alarm is displayed. In this case, when the differential pressure is within an appropriate range, the compressor is restarted.
[0014]
Furthermore, after switching the four-way switching valve, the detection result is taken from the pressure detection means, the differential pressure between the discharge side pressure and the suction side pressure of the compressor is calculated, and if the differential pressure is an abnormal value, the compressor is It can also be configured to stop. In this case, after the compressor is stopped and a predetermined time elapses, the compressor is restarted and the differential pressure is calculated. If the differential pressure is an abnormal value, the compressor is stopped. Also, when the compressor is started and stopped a predetermined number of times, an alarm display is performed.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 is a configuration diagram of a heat pump heat supply apparatus according to the present invention. As shown in the figure, the compressor 1, the four-way switching valve 2, the first heat exchanger 3, the expansion valve 4, the second heat exchanger 5, and the four-way switching valve 2 are sequentially connected to form a refrigeration cycle. ing. That is, the discharge side of the compressor 1 is connected to the four-way switching valve 2 via the refrigerant flow path L1, and the four-way switching valve 2 is connected to the first heat exchanger 3 via the refrigerant flow path L2 for the first heat exchange. The vessel 3 is connected to the expansion valve 4 via the refrigerant flow path L3. The expansion valve 4 is connected to the second heat exchanger 5 via the refrigerant flow path L4, the second heat exchanger 5 is connected to the four-way switching valve 2 via the refrigerant flow path L5, and the four-way switching valve 2 is connected to the refrigerant flow. Each is connected to the suction side of the compressor 1 via a path L6.
[0016]
The first heat exchanger 3 is a heat exchanger on the heat source side and is air-cooled by the cooling fan 6. In addition, the second heat exchanger 5 is a heat exchanger on the use side, to which the inflow pipe 5A and the outflow pipe 5B are attached, and the water flowing in from the inflow pipe 5A flows through the inside, and then flows out from the outflow pipe 5B.
[0017]
The refrigerant circulates in the refrigeration cycle, and the refrigerant flows as shown by the solid line arrow in the drawing during the operation of cooling the water flowing through the second heat exchanger 5 (hereinafter referred to as the cold water supply operation). During operation (hereinafter referred to as hot water supply operation), the refrigerant flows as indicated by the broken-line arrows in the figure. The four-way switching valve 2 is switched as indicated by a solid line during cold water supply operation and as indicated by a broken line during hot water supply operation.
[0018]
The refrigerant flow path L1 is provided with a pressure sensor 7 for detecting the discharge side refrigerant pressure of the compressor 1, and the refrigerant flow path L6 is provided with a pressure sensor 8 for detecting the suction side refrigerant pressure of the compressor 1. A control device 9 to which detection signals from the pressure sensors 7 and 8 are input is installed.
[0019]
In the above configuration, during the cold water supply operation, the high-temperature and high-pressure gas refrigerant compressed by the compressor 1 is guided to the four-way switching valve 2 via the refrigerant flow path L1, and the four-way switching valve 2 is moved along the solid flow path. Then, it is guided to the first heat exchanger 3 through the refrigerant flow path L2. In the first heat exchanger 3, the high-temperature and high-pressure gas refrigerant is condensed by exchanging heat with the air blown by the cooling fan 6, and becomes a high-temperature and high-pressure liquid refrigerant. The high-temperature and high-pressure liquid refrigerant is guided to the expansion valve 4 through the refrigerant flow path L3, and is decompressed by the expansion valve 4 to become a low-temperature and low-pressure two-phase refrigerant. Further, the second heat exchange is performed through the refrigerant flow path L4. Guided to vessel 5. In the second heat exchanger 5, the low-temperature and low-pressure two-phase refrigerant exchanges heat with water flowing through the second heat exchanger 5 to cool the water. Thereby, cold water can be obtained from the second heat exchanger 5.
[0020]
The low-temperature and low-pressure two-phase refrigerant that has exchanged heat with water in the second heat exchanger 5 evaporates to become a low-temperature and low-pressure gas refrigerant, and is led to the four-way switching valve 2 via the refrigerant flow path L5. , The refrigerant is returned to the compressor 1 through the refrigerant flow path L6 and compressed again by the compressor 1.
[0021]
During the hot water supply operation, the high-temperature and high-pressure gas refrigerant compressed by the compressor 1 is guided to the four-way switching valve 2 through the refrigerant flow path L1, and flows through the four-way switching valve 2 along the broken flow path. Then, it is guided to the second heat exchanger 5 through the refrigerant flow path L5. In the second heat exchanger 5, the high-temperature and high-pressure gas refrigerant exchanges heat with water flowing through the second heat exchanger 5 to heat the water. Thereby, warm water can be obtained from the second heat exchanger 5.
[0022]
The high-temperature and high-pressure gas refrigerant exchanged with water in the second heat exchanger 5 is condensed to become a high-temperature and high-pressure liquid refrigerant. The high-temperature and high-pressure liquid refrigerant is guided to the expansion valve 4 through the refrigerant flow path L4, and is decompressed by the expansion valve 4 to become a low-temperature and low-pressure two-phase refrigerant, and further, the first heat exchange is performed through the refrigerant flow path L3. Guided to vessel 3. In the first heat exchanger 3, the low-temperature and low-pressure two-phase refrigerant evaporates by exchanging heat with the air blown by the cooling fan 6 and becomes a low-temperature and low-pressure gas refrigerant. The low-temperature and low-pressure gas refrigerant is guided to the four-way switching valve 2 via the refrigerant flow path L2, passes through the four-way switching valve 2, and then returns to the compressor 1 via the refrigerant flow path L6. Is compressed again.
[0023]
2 and 3 show the configuration of the four-way switching valve 2 and its driving mechanism. FIG. 2 shows the state during the cold water supply operation, and FIG. 3 shows the state during the hot water supply operation.
As shown in FIGS. 2 and 3, the four-way switching valve 2 is provided with flow path connecting portions 2A, 2B, 2C, 2D, the flow path connecting portion 2A is a refrigerant flow path L1, and the flow path connecting section 2B is a refrigerant. In the flow path L5, the flow path connection portion 2C is connected to the refrigerant flow path L6, and the flow path connection portion 2D is connected to the refrigerant flow path L2. The four-way switching valve 2 is provided with a semicircular valve body 2E in a movable manner inside, and the valve body 2E is connected to pistons 2F and 2G arranged on both sides thereof, and the piston 2F, When 2G moves inside the four-way switching valve 2 in the left-right direction in the figure, it moves in the left-right direction in conjunction with it. As a result, the flow path connection portion 2A can be connected to the flow path connection portion 2D as shown in FIG. 2, and the flow path connection portion 2C can be connected to the flow path connection portion 2B. Also, as shown in FIG. 2A can be connected to the flow path connection portion 2B, and the flow path connection portion 2C can be connected to the flow path connection portion 2D.
[0024]
Further, a flow path switching control valve 10 is provided, and the flow path switching control valve 10 is operated to switch the pressure in the flow path connection portion 2A to the pressure chamber 2H or the pressure chamber 2I of the four-way switching valve 2, or the flow path. By transmitting the pressure in the connecting portion 2C to the pressure chamber 2H or the pressure chamber 2I, the pistons 2F and 2G move inside the four-way switching valve 2 in the left-right direction in the figure.
[0025]
During the cold water supply operation, the flow path switching control valve 10 is switched as shown in FIG. Since the high-temperature and high-pressure gas refrigerant compressed by the compressor 1 flows in the flow path connection portion 2A, and the low-temperature and low-pressure gas refrigerant sucked by the compressor 1 flows in the flow path connection portion 2C, the pressure chamber 2I On the high-pressure side, the pressure chamber 2H becomes the low-pressure side, and the pistons 2F and 2G are pushed in the left direction in the figure, and the valve body 2E also moves in the same direction. Thereby, the high-temperature and high-pressure gas refrigerant flows from the flow path connection portion 2A to the flow path connection portion 2D, and the low-temperature and low-pressure gas refrigerant flows from the flow path connection portion 2B to the flow path connection portion 2C.
[0026]
During the hot water supply operation, the flow path switching control valve 10 is switched as shown in FIG. In this case, the pressure chamber 2I is on the low pressure side, the pressure chamber 2H is on the high pressure side, the pistons 2F and 2G are pushed rightward in the figure, and the valve body 2E is also moved in the same direction. Thereby, the high-temperature and high-pressure gas refrigerant flows from the flow path connection portion 2A to the flow path connection portion 2B, and the low-temperature and low-pressure gas refrigerant flows from the flow path connection portion 2D to the flow path connection portion 2C.
[0027]
FIG. 4 shows an operation flowchart of the heat pump type heat supply apparatus in the present embodiment. The compressor 1 has a function of switching the discharge amount stepwise between 50%, 75%, and 100%. Here, when the refrigeration cycle is switched from the cold water supply operation to the hot water supply operation, or from the hot water supply operation to the cold water supply operation, the discharge side pressure Pd of the compressor 1 is detected by the pressure sensor 7 and the suction side pressure Ps is detected by the pressure sensor. 8 to detect. Detection signals from the pressure sensors 7, 8 are input to the control device 9, and the control device 9 calculates a differential pressure ΔP = Pd−Ps based on the input detection signals. Then, the control device 9 determines whether or not the differential pressure ΔP is within an appropriate range. If the differential pressure ΔP exceeds 0.075 MPa, the discharge amount of the compressor 1 is reduced to 75%. As a result, there is room in the heat transfer area of the heat exchangers 3 and 5, the discharge side pressure Pd decreases, the suction side pressure Ps increases, and the differential pressure ΔP decreases. And after predetermined time progress, differential pressure (DELTA) P is calculated again, and if it is 0.075 Mpa or less, the four-way selector valve 2 will be switched. When the pressure still exceeds 0.075 MPa, the discharge amount of the compressor 1 is reduced to 50% to reduce the differential pressure ΔP, and when it becomes 0.075 MPa or less, the four-way switching valve 2 is switched.
[0028]
On the other hand, when the differential pressure ΔP is less than 0.035 MPa, the differential pressure ΔP is increased by increasing the discharge amount of the compressor 1 to 75% and 100%. Switch.
[0029]
If the differential pressure ΔP does not fall within the range of 0.035 MPa ≦ ΔP ≦ 0.075 MPa even if the discharge amount of the compressor 1 is decreased or increased, the compressor 1 is stopped and an alarm is displayed.
[0030]
Further, the differential pressure ΔP after switching the four-way switching valve 2 is calculated, and when the differential pressure ΔP is an abnormal value, for example, 0 to 0.02 MPa, the valve body of the four-way switching valve 2 stops at an intermediate position, or The operation of the refrigeration cycle is stopped because it is determined that the valve body is not properly switched.
[0031]
When a predetermined time has elapsed from the stop, the re-operation is resumed. If the differential pressure ΔP exceeds 0.02 MPa, the operation is continued, and if it is 0 to 0.02 MPa, the operation is stopped. When the operation is restarted / stopped a predetermined number of times, an alarm is displayed that the four-way switching valve 2 is abnormal, and the refrigeration cycle operation is completely stopped.
[0032]
As described above, in the present embodiment, the discharge amount of the compressor 1 is adjusted so as to switch the four-way switching valve 2 within the range where the differential pressure ΔP is 0.035 MPa ≦ ΔP ≦ 0.075 MPa, and the four-way switching valve. If the differential pressure ΔP after switching 2 is an abnormal value, the operation is stopped, the operation is restarted a predetermined number of times, an alarm is displayed, and the operation is stopped.
[0033]
FIG. 5 shows the relationship between the differential pressure ΔP during operation of the four-way switching valve and the service life depending on the number of switching times. As can be seen from the figure, if the differential pressure ΔP is large, the four-way switching valve is liable to fail even if the number of switching is small, and the life is shortened. On the other hand, if the differential pressure ΔP is small, the four-way switching valve is less likely to fail even if the number of switching is large, and the life is extended. Therefore, in the present embodiment, in consideration of specifying the mechanical and strength life of the four-way switching valve, control is performed so that the four-way switching valve is switched within an appropriate differential pressure range.
[0034]
According to the present embodiment, by controlling the differential pressure applied to the four-way switching valve 2, an appropriate differential pressure is applied to the valve body when the four-way switching valve 2 is switched. Can be prevented, and the life of the four-way switching valve 2 can be extended.
[0035]
Further, by obtaining the differential pressure after switching the four-way switching valve 2, it is possible to detect whether or not the valve body of the four-way switching valve 2 is stopped at the intermediate position, and the valve body is stopped at the intermediate position. If this is the case, the operation is stopped, and the operation is automatically resumed after a predetermined time, thereby protecting the refrigeration cycle and improving the reliability of the entire system.
[0036]
In the present embodiment, the four-way switching valve 2 is switched within the range where the differential pressure ΔP is 0.035 MPa ≦ ΔP ≦ 0.075 MPa. However, the differential pressure depends on how many times the switching is performed. ΔP can be changed.
[0037]
Further, the fluid flowing through the second heat exchanger 5 is not limited to water but may be other fluids.
[0038]
(Embodiment 2)
FIG. 6 shows a second embodiment of the present invention. In the present embodiment, the compressor 1 is configured so that a predetermined discharge amount can be continuously changed. Other configurations are the same as those of the first embodiment. That is, the configuration of the refrigeration cycle is the same as that shown in FIG. 1, and the configuration of the four-way switching valve 2 is also the same as that shown in FIGS.
[0039]
In the present embodiment, the control device 9 calculates a differential pressure ΔP for switching the four-way switching valve 2, and when the differential pressure ΔP exceeds 0.075 MPa, the discharge amount of the compressor 1 is set to a predetermined amount, for example, 5%. Decrease (Note that the predetermined amount is an arbitrary value). Then, after a predetermined time has elapsed, the differential pressure ΔP is calculated again, and if it exceeds 0.075 MPa, the discharge amount is similarly reduced by 5%, and the differential pressure ΔP is adjusted to 0.075 MPa or less.
[0040]
Similarly, when the differential pressure ΔP is less than 0.035 MPa, the discharge amount of the compressor 1 is similarly increased by a predetermined amount, and the four-way switching valve 2 is switched when the differential pressure ΔP becomes 0.035 MPa or more.
[0041]
According to the present embodiment, the differential pressure applied to the four-way switching valve 1 is detected, and the discharge amount of the compressor 1 is changed by a predetermined amount, so that the valve body of the four-way switching valve 2 is changed as in the first embodiment. It is possible to prevent cracking and breakage and to prevent the valve body from stopping at an intermediate position. Furthermore, in the present embodiment, since the discharge amount from the compressor 1 is continuously controlled by a predetermined amount, it is not necessary to add a capacity limit more than necessary due to a delay in volume reduction. That is, it is possible to minimize a decrease in the ability to supply cold water or hot water.
[0042]
(Embodiment 3)
Next, Embodiment 3 will be described with reference to FIG. As in the case of the first embodiment, the compressor 1 has a function of switching the discharge amount in steps of 50%, 75%, and 100%. Here, when switching from the hot water supply operation to the defrosting operation, the discharge side pressure Pd of the compressor 1 is detected by the pressure sensor 7, and the suction side pressure Ps is detected by the pressure sensor 8. Detection signals from the pressure sensors 7, 8 are input to the control device 9, and the control device 9 calculates a differential pressure ΔP = Pd−Ps. Then, the control device 9 determines whether or not the differential pressure ΔP is equal to or less than ΔPmax, and if it exceeds ΔPmax, the discharge amount of the compressor 1 is changed (for example, the discharge amount is reduced to 75%). After a certain time elapses, the differential pressure ΔP is calculated again, and if it is equal to or less than ΔPmax, the four-way switching valve 2 is switched. If it still exceeds ΔPmax, the discharge amount of the compressor 1 is further changed (for example, the discharge amount is reduced to 50%). And if it becomes below (DELTA) Pmax, the four-way selector valve 2 will be switched.
[0043]
Further, the differential pressure ΔP after switching the four-way switching valve 2 is calculated, and when the differential pressure ΔP is less than the abnormal value ΔPmin, the valve body of the four-way switching valve 2 stops at the intermediate position, or the switching of the valve body is poor. Therefore, the operation of the refrigeration cycle (that is, the operation of the compressor 1) is stopped.
[0044]
When a predetermined time has elapsed from the stop, the re-operation is resumed. If the differential pressure ΔP is equal to or greater than ΔPmin, the operation is continued, and if it is less than ΔPmin, the operation is stopped. When the operation is restarted / stopped a predetermined number of times, an alarm is displayed that the four-way switching valve 2 is abnormal, and the refrigeration cycle operation is completely stopped. Specific examples of ΔPmax and ΔPmin are shown in FIG.
[0045]
As described above, in the present embodiment, the discharge amount of the compressor is adjusted so that the differential pressure ΔP is switched between the four-way switching valves within the range of ΔPmin to ΔPmax, and when the differential pressure ΔP is an abnormal value, the operation is stopped. After restarting a predetermined number of times, an alarm is displayed and the operation is stopped.
According to the present embodiment, the same effect as in the first embodiment can be obtained.
[0046]
(Embodiment 4)
Next, Embodiment 4 will be described with reference to FIG. As in the second embodiment, the compressor 1 can continuously change the predetermined discharge amount.
[0047]
In the present embodiment, the control device 9 calculates a differential pressure ΔP for switching the four-way switching valve 2, and when the differential pressure ΔP exceeds ΔPmax, the discharge amount of the compressor 1 is changed to a predetermined amount, for example, 5 % Decrease. Then, after a predetermined time has elapsed, the differential pressure ΔP is calculated again, and if it is equal to or less than ΔPmax, the four-way switching valve 2 is switched, and if it exceeds ΔPmax, the discharge amount of the compressor 1 is changed (decreased) by a predetermined amount. The pressure ΔP is reduced and adjusted repeatedly so as to be equal to or less than ΔPmax.
According to the present embodiment, the same effect as in the second embodiment can be obtained.
[0048]
【The invention's effect】
As described above, according to the present invention, by calculating the differential pressure for switching the four-way switching valve and switching the four-way switching valve in an appropriate differential pressure state, it is possible to prevent the valve body from being cracked or damaged. It is also possible to prevent the body from stopping at an intermediate position. As a result, the reliability of the four-way switching valve is improved and the life can be extended.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a heat pump heat supply device according to the present invention.
FIG. 2 is a diagram showing a state of a four-way switching valve during a cold water supply operation.
FIG. 3 is a diagram showing a state of a four-way switching valve during a hot water supply operation.
FIG. 4 is an operation flowchart according to the first embodiment of the present invention.
FIG. 5 is a life diagram of a four-way switching valve.
FIG. 6 is an operation flowchart according to the second embodiment of the present invention.
FIG. 7 is an operation flowchart according to the third embodiment of the present invention.
FIG. 8 is an operation flowchart according to the fourth embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Compressor 2 Four-way selector valve 3 1st heat exchanger 4 Expansion valve 5 2nd heat exchanger 6 Cooling fan 7, 8 Pressure sensor (pressure detection means)
9 Control device (control means)
10 Channel switching control valve

Claims

A compressor, a first heat exchanger, a decompressor, a second heat exchanger, and a refrigeration cycle to which a four-way switching valve is sequentially connected, wherein the first heat exchanger flows outside the heat exchanger And the refrigerant circulating in the refrigeration cycle, the second heat exchanger exchanges heat between the fluid flowing through the heat exchanger and the refrigerant, and When the four-way switching valve is switched and the refrigerant flows in the order of the first heat exchanger, the pressure reducer, and the second heat exchanger, the fluid is cooled and supplied, and the four-way switching valve is reversed. In the heat pump type heat supply device in which the fluid is heated and supplied when the refrigerant flows in the order of the second heat exchanger, the decompressor, and the first heat exchanger. ,
Pressure detecting means for detecting a discharge side pressure and a suction side pressure of the compressor;
The detection result is taken in from the pressure detection means to calculate the differential pressure between the discharge side pressure and the suction side pressure of the compressor, and when the four-way switching valve is switched, the differential pressure is within a preset appropriate range. determines whether or not contained, in the case of out of the proper range, and control means for switching the four-way selector valve from entering into the differential pressure appropriate value range by changing the discharge amount of the compressor The appropriate range is determined from a life characteristic of the number of switching times of the four-way switching valve determined according to the differential pressure .

A compressor, a first heat exchanger, a decompressor, a second heat exchanger, and a refrigeration cycle to which a four-way switching valve is sequentially connected, wherein the first heat exchanger flows outside the heat exchanger And the refrigerant circulating in the refrigeration cycle, the second heat exchanger exchanges heat between the fluid flowing through the heat exchanger and the refrigerant, and When the four-way switching valve is switched and the refrigerant flows in the order of the first heat exchanger, the pressure reducer, and the second heat exchanger, the fluid is cooled and supplied, and the four-way switching valve is reversed. In the heat pump type heat supply device in which the fluid is heated and supplied when the refrigerant flows in the order of the second heat exchanger, the decompressor, and the first heat exchanger. ,
Pressure detecting means for detecting a discharge side pressure and a suction side pressure of the compressor;
The detection result is taken in from the pressure detection means to calculate the differential pressure between the discharge side pressure and the suction side pressure of the compressor, and when the four-way switching valve is switched, the differential pressure is within a preset appropriate range. Determine whether or not, if it exceeds the upper limit of the appropriate range, decrease the discharge amount of the compressor, if less than the lower limit value of the appropriate range, increase the discharge amount of the compressor, Control means for switching the four-way switching valve after the differential pressure falls within an appropriate value range, and the appropriate range is determined from the life characteristics of the number of switching times of the four-way switching valve determined according to the differential pressure. A heat pump type heat supply device.

A compressor, a first heat exchanger, a decompressor, a second heat exchanger, and a refrigeration cycle to which a four-way switching valve is sequentially connected, wherein the first heat exchanger flows outside the heat exchanger And the refrigerant circulating in the refrigeration cycle, the second heat exchanger exchanges heat between the fluid flowing through the heat exchanger and the refrigerant, and When the four-way switching valve is switched and the refrigerant flows in the order of the first heat exchanger, the pressure reducer, and the second heat exchanger, the fluid is cooled and supplied, and the four-way switching valve is reversed. In the heat pump type heat supply device in which the fluid is heated and supplied when the refrigerant flows in the order of the second heat exchanger, the decompressor, and the first heat exchanger. ,
Pressure detecting means for detecting a discharge side pressure and a suction side pressure of the compressor;
The detection result is taken in from the pressure detection means to calculate the differential pressure between the discharge side pressure and the suction side pressure of the compressor, and when the four-way switching valve is switched, the differential pressure is within a preset appropriate range. Control means for switching the four-way switching valve after changing the discharge amount of the compressor and entering the appropriate pressure range when the pressure difference is within the appropriate value range. When the pressure difference does not fall within an appropriate range even if the discharge amount of the compressor is decreased or increased, the control means stops the compressor and displays a warning. Type heat supply device.

A compressor, a first heat exchanger, a decompressor, a second heat exchanger, and a refrigeration cycle sequentially connected to the four-way switching valve, wherein the first heat exchanger is an empty air flowing outside the heat exchanger; Heat exchange between the refrigerant circulating in the refrigeration cycle and the second heat exchanger exchanges heat between the fluid flowing through the heat exchanger and the refrigerant, The fluid is cooled and supplied when the four-way switching valve is switched and the refrigerant flows in the order of the first heat exchanger, the pressure reducer, and the second heat exchanger. The heat pump type heat supply device is switched to the reverse, and the fluid is heated and supplied when the refrigerant flows in the order of the second heat exchanger, the pressure reducer, and the first heat exchanger. In
Pressure detecting means for detecting a discharge side pressure and a suction side pressure of the compressor;
The detection result is taken in from the pressure detection means to calculate the differential pressure between the discharge side pressure and the suction side pressure of the compressor, and when the four-way switching valve is switched, the differential pressure is within a preset appropriate range. Determine whether or not, if it exceeds the upper limit of the appropriate range, decrease the discharge amount of the compressor, if less than the lower limit value of the appropriate range, increase the discharge amount of the compressor, Control means for switching the four-way switching valve after the differential pressure is within an appropriate value range, and the control means can maintain the differential pressure within an appropriate range even if the discharge amount of the compressor is decreased or increased. When the heat pump does not enter the heat pump , the compressor is stopped and a warning is displayed .

In the heat pump type heat supply device according to claim 3 or 4,
The heat pump type heat supply device, wherein the control means restarts the compressor when the differential pressure is within an appropriate range.