JP3776999B2

JP3776999B2 - One can two water channel combustion system

Info

Publication number: JP3776999B2
Application number: JP33917296A
Authority: JP
Inventors: 幸伸野口; 良彦田中
Original assignee: 株式会社ガスター
Priority date: 1996-12-19
Filing date: 1996-12-19
Publication date: 2006-05-24
Anticipated expiration: 2016-12-19
Also published as: JPH10185310A

Description

【０００１】
【発明の属する技術分野】
本発明は、給湯路と風呂追い焚き路が単一の熱交換器内を通過する一缶二水路式の燃焼装置に関するものである。
【０００２】
【従来の技術】
従来、いわゆる一缶二水路式燃焼装置において、給湯が行われているとき、即ち、バーナーが燃焼し、給湯側缶体部に水が流れているときに、風呂の追い焚き指令が出されると、循環ポンプを駆動させ、風呂側缶体部に水を流すことによって風呂追い焚きは開始され、さらに、給湯と風呂の追い焚き両方が行われているときに、追い焚きの停止指令が出されると、循環ポンプを止め、風呂側缶体部への水の流れを止めることによって、風呂追い焚きは止められていた。
【０００３】
【発明が解決しようとする課題】
しかし、給湯中に追い焚き指令が出されることにより、風呂側缶体部に水を流すと、いままで、給湯側缶体部に流れている水の加熱に使われていたバーナーの燃焼による熱量の一部が、風呂側缶体部に流れる水の加熱のために使用されることとなる。そのため、給湯側缶体部に流れる水を所定の設定温度まで加熱する熱量が不足し、給湯温度は低下する。このとき、例えば、給湯温度サーミスタにより検出される給湯温度の温度低下を検知してから、給湯側缶体部に流れる水に所定温度まで加熱するための熱量を与えるように、供給ガス量を増加させる燃焼制御が行われるが、一時的な給湯温度の変化は避けられない。
【０００４】
また、給湯と風呂追い焚きが同時に行われているとき、風呂追い焚きの停止指令が出されることにより、風呂側缶体部に流れる水の流れが止まる。そのため、給湯側缶体部に流れる水にそれを所定温度まで加熱するのに必要な熱量より多い熱量が与えられてしまい、給湯温度は設定温度以上に上昇する。このとき、上述同様に、例えば、給湯温度サーミスタにより検出される給湯温度の温度上昇を検知してから、給湯側缶体部に流れる水を所定の設定温度まで加熱するための熱量を与えるように、供給ガス量を減少させる燃焼制御が行われるが、一時的な給湯温度の変化は避けられない。
【０００５】
そこで、本発明は、給湯中に風呂追い焚きが開始されたとき、及び、給湯と風呂追い焚きの同時使用中に風呂の追い焚きが止められたときに、給湯温度が一定に維持されるようにすることを目的とする。
【０００６】
【課題を解決するための手段】
上記本発明の目的は、給湯を行うための給湯側缶体部部及び風呂追い焚きを行うための風呂側缶体部からなる缶体を備えた一缶二水路式燃焼装置において、
前記風呂側缶体部の出口側に接続された第一の管路と、
前記風呂側缶体部の入口側に接続された第二の管路と、
該第二の管路に設けられ、前記風呂側缶体部に水を送るポンプと、
前記第一の管路から分岐し、前記ポンプの上流側の前記第二の管路に接続されたバイパス管と、
分岐前の前記第一の管路に流れる水の流量を、前記バイパス管及び分岐後の前記第一の管路に任意の比率で分配することができる弁とを有することを特徴とする燃焼装置を提供することにより達成される。
【０００７】
また、給湯と風呂追い焚きが同時に行われているときに、風呂追い焚き停止指令が出された場合、前記弁を分岐前の前記第一の管路に流れる流量のほぼ全量を前記バイパス管に分配するように作動させ、それに合わせて、前記缶体に与える熱量を徐々に減少させることによって上記燃焼装置は制御される。
【０００８】
前記缶体に与える熱量は、前記給湯側缶体部を流れる水の温度に従って減少させられることが好ましい。
【０００９】
また、前記風呂側缶体部に流れる水の温度が所定温度に達したとき、即ち、前記風呂側缶体部に流れる水が熱交換をこれ以上を行わなくなったときに、ポンプの作動が停止されるように上記燃焼装置は制御される。
【００１０】
さらに、給湯のみが行われているときに、風呂追い焚き指令が出された場合、前記ポンプを作動させ、前記弁を分岐前の前記第一の管路に流れる流量のほぼ全量を前記バイパス管に分配する状態から分岐後の前記第一の管路に分配する状態に作動させると共に、前記缶体に与える熱量を徐々に増加させることによって上記燃焼装置は制御される。
【００１１】
前記缶体に与える熱量は、前記給湯側缶体部を流れる水の温度に従って増加させられることが好ましい。
【００１２】
また、前記風呂側缶体部に流れる水の温度が所定温度に達した後に、前記弁の作動及び前記缶体に与えられる熱量の増加が行われるように上記燃焼装置が制御されてもよい。
【００１３】
【発明の実施の形態】
以下、本発明の実施の形態について図面に従って説明する。しかしながら、本発明の技術的範囲がこの実施の形態に限定されるものではない。
【００１４】
図１は、本発明の実施の形態における一缶二水路式燃焼装置の概略構成図である。図１において、缶体１は、給湯側缶体部１ａと風呂側缶体部１ｂとからなり、フィン２を共有している。缶体１は、バーナー３によって加熱され、バーナー３には、ガス供給通路４から燃料ガスが供給される。ガス供給通路４には、このガス供給通路４の開閉を行うガス電磁弁２４とガス供給量を調節するガス比例弁２５が設けられている。バーナー２の上面側にはバーナー２の点火を行うイグナイタ電極５と炎を検知するフレームロッド電極６が設けられている。
【００１５】
給湯側缶体部１ａの入口側には、給湯側缶体部１ａに水を供給する給水通路として機能する給水管７が接続されており、この給水管７には、給湯側缶体部１ａに供給する水の温度を検出する給水側入水温度センサ８と、給湯側缶体部１ａに供給される水の流量を検出する給湯側水量センサ９が設けられている。給湯側缶体部１ａの出口側には、給湯側缶体部１ａによって加熱された湯が出湯される給湯管１０が接続され、台所などの所望の場所に導かれる。この給湯管１０には、給湯側缶体部１ａから出湯される湯の温度を検出する給湯側出湯温度センサ１１が設けられている。
【００１６】
一方、風呂側缶体部１ｂには、その入口側及び出口側にそれぞれ入口側追い焚き循環管路１３ａ及び出口側追い焚き循環管路１３ｂが接続されており、さらに、両追い焚き循環管路１３ａ、ｂは浴槽１４に接続されている。また、入口側追い焚き循環管路１３ａには、循環ポンプ１５が設けられており、この循環ポンプ１５の作動により、浴槽１４内の湯水が風呂側缶体部１ｂも送られるようになっている。さらに、風呂側入水温度センサ１６及び風呂側水量センサ１７が循環ポンプ１５の下流側に取り付けられている。
【００１７】
また、この一缶二水路式燃焼装置には制御装置２０が設けられており、制御装置２０にはリモコン２１が接続されている。リモコン２１の指示などに従い、制御装置２０により給湯及び追い焚きの燃焼制御が行われるようになっている。例えば、台所などで給湯栓２８が開けられると、給水管７に水が流れ、それを給湯側入水センサ９が検知する。制御装置２０は給湯側水量センサ９から入水検知信号を受けると、ガス供給通路４のガス電磁弁２４とガス比例弁２５を開けて、イグナイタ電極５を放電させ点火を行い、フレームロッド電極６で炎を検知した後に、給湯温度センサ１１で検出される給湯温度がリモコン２１で設定される設定温度となるように、ガス比例弁２５の開度を制御する。そして、このような制御により給湯管１０からはリモコン２１で設定した設定温度の湯が台所などの所望の場所に供給される。
【００１８】
また、リモコン２１などで追い焚き運転が指令されたときには、制御装置２０は、追い焚き循環管路１３の循環ポンプ１５を駆動させて、浴槽１４内の水（湯）を追い焚き循環管路１３を介して循環させる。そして、風呂側水量センサ１７が水（湯）の流れを検知すると、制御装置２０はガス供給通路４のガス電磁弁２４及びガス比例弁２５を開き、点火によりバーナ２を燃焼させて風呂側缶体部１ｂを通る循環湯水を加熱して浴槽１４内の水（湯）の追い焚きを行う。そして、風呂側出湯温度センサ２２で検出される風呂温度がリモコン２１によって設定される風呂設定温度に達したときに追い焚き運転は停止される。
【００１９】
また、本発明における一缶二水路式燃焼装置においては、三方弁１８が、風呂側缶体部１ｂから出湯された湯の一部又は全部を浴槽１４をバイパスさせて、風呂側缶体部１ｂの出湯側から循環ポンプ１５の上流側に接続されたバイパス管１９が設けられている。三方弁１８は、風呂側缶体部１ｂの出口側からの流量を、浴槽１４及びバイパス管１９に任意の比率で分配することができる。
【００２０】
図２は、三方弁１８を説明するための図である。図２（ａ）はその三方弁１８の構成図であり、１つの入水通路と２つの出水通路I、IIが設けられた管部分１８１と図示しないモータによって回転される回転体部分１８２によって構成される。図２（ｂ）及び（ｃ）は、それぞれ回転体部分１８２の側面図及び断面図である。これらの図によれば、回転体部分１８２は、その内部に流れ込む水を出水通路I、IIへ流すための断面積の異なる複数の穴が回転体部分１８２の側面に設けられている。これらの穴は、回転体１８２の中心軸に対向している２つの穴の断面積の和が一定になるように配置されている。
【００２１】
従って、回転体１８２を管部分１８１に対して回転させ、任意の位置に位置決めすることにより、入水通路からの水を２つの出水通路I、IIに任意の流量比率で分配できる。例えば、図２（ｄ）に示すように、回転体１８２が上記出水通路I、IIに対して図２（ｃ）における位置（１）に位置決めされた場合、同量即ち流量比I：II＝0.5:0.5 の水が出水通路I、IIに流れ、位置（２）に位置決めされた場合、２つの出水通路I、IIに流れる流量比はI：II＝0.1:0.9 となる。
【００２２】
また、図２（ｄ）において、三方弁１８がＡの状態にあるときは、図１において、出湯された湯はすべて浴槽１４へ流れ込み、バイパス管１９には流れない状態であることを示す。さらに、Ｂの状態にあるときは、出湯された湯はすべてバイパス管１９に流れ、浴槽１４へは流れない状態であることを示す。
【００２３】
今、上述したような燃焼装置において、給湯と風呂の追い焚きが両方行われているとき、風呂側缶体部１ｂには、循環ポンプ１５の駆動により湯が流れている。このとき、三方弁１８は、風呂側缶体部１ｂから出湯された湯をすべて浴槽１４へ流し、バイパス管１９には湯が流れないように調節されている。即ち、図２（ｄ）において、Ａの状態にある。このとき、リモコン２１などにより風呂追い焚きの停止指令が出されると、上述のように、従来は、循環ポンプ１５が止められ、風呂側缶体部１ｂにおける熱交換量が急減することによって給湯温度の一時的な上昇を招いていたが、本発明においては、以下に述べる第一の実施の形態によって給湯温度を制御する。
【００２４】
図５は、本発明の実施の形態の動作を説明するフローチャートであり、さらに、図３は、本実施の第一の実施の形態における、（ａ）給湯側缶体部１ａ内の水の温度、（ｂ）風呂側缶体部１ｂ内の水の温度、（ｃ）ガス比例弁２５開度、（ｄ）循環ポンプ１５及び（ｅ）三方弁１８の状態を示すグラフである。
【００２５】
まず、図５におけるステップＳ１において、追い焚き停止指令が出された場合、ステップＳ２において三方弁１８の位置は図２における状態Ａから状態Ｂに調節される（図３（ｅ）実線部参照）。これにより、浴槽１４への流れが止められ、風呂側缶体部１ｂから出湯された湯すべてがバイパス管１９へ流れる。一方、循環ポンプ１５は図３（ｄ）に示すように第一の時間である所定時間ｔ₁の間止めず、湯をバイパス管１９を経由させて風呂側缶体部１ｂに流しつづける。この結果、浴槽１４に加熱された湯が循環しないので、浴槽湯への追い焚きは停止するが、風呂側缶体部１ｂには湯が流れ続けているので、風呂側缶体部１ｂ内においては引き続き熱交換が行われるので、図３（ａ）の実線部に示すように、給湯側缶体部１ｂに与えられる熱量はほぼ変化せず、給湯側缶体部１ａ内の水温は一定に保たれる。
【００２６】
この点について詳しく説明すると、バイパス管１９を経由して流れる湯が三方弁１８の駆動時間に応じて、少量から全量に変化をつづけ、図３（ｂ）に示すように、比較的時間をかけて湯の温度が上昇する。これにつれて、給湯側缶体１ａに与えられる熱量は増加するが、給湯側出湯サーミスタ１１による比例弁２５の開度調整（フィードバック）制御追従範囲内の温度変化量（単位時間当たり）なので、図３（ａ）に示されように、給湯温度の変化はない。
【００２７】
三方弁１８の駆動が終了し、追い焚き循環管路１３ａ、ｂに流れる湯水の全量がバイパス管１９を通るようになると、比較的短時間に追い焚き循環管路１３ａ、ｂに流れる湯水の温度が上昇する。これにつれて、給湯側缶体部１ａに与えられる熱量が増加し、給湯側出湯サーミスタ１１による給湯湯温の更なる上昇検知による比例弁２５の開度調整が行われるまでの（フィードバック制御であるがための）タイムラグΔＸにより給湯温度に少量の上昇が起きる。
【００２８】
さらに詳しくは、この給湯温度の少量の上昇は、図３（ｂ）に示すように、風呂側缶体１ａ内の温度変化量が、フィードバック制御によって比例弁２５の開度を制御した場合の給湯湯温の変化が起きない範囲内の上限変化量θ’より大きい変化量θとなったとき、給湯側出湯サーミスタ１１によって、その変化量θを検出してフィードバック制御が行われるまでの時間ΔＸの遅れによって生じる。図３（ｂ）において、変化量θがＸ時間後に上限変化量θ’以内になった場合、ΔＸ時間経過後Ｘ’時間で変化量θに対応する比例弁２５の制御を行うが、ΔＸ時＋Ｘ’時間の間、給湯湯温は図３（ａ）に示すように若干変化する。その後、給湯温度は設定温度に戻り維持される。
【００２９】
上記給湯温度の上昇が起きたとき、あらかじめ、三方弁１８の位置Ａから位置Ｂへの駆動により比例弁２５の開度が絞られる方向に制御が開始されており、かつ、後述するポンプ駆動の継続により図３（ｂ）に示されるように、従来のポンプの駆動停止による単位時間当たりの温度変化量Ｙが、本願ではＹ’となるが、この値以上に給湯温度への影響が少なくなる。また、前述の給湯温度の少量の上昇すら三方弁１８の駆動時間を制御したり、後述するバッファタンクを設けたりすることで解消することができる。
【００３０】
三方弁１８の駆動時間を制御する方法は、給湯湯温が変化しないように比例弁２５の開度調整（フィードバック）制御追従範囲内となるように、位置Ａから位置Ｂへの駆動時間を制御すればよい。この場合、リモコン２１の風呂設定温度より所定量低い温度から三方弁１８の駆動を開始し（位置Ａ）、リモコン２１の風呂設定温度となった時点で駆動を停止する（位置Ｂ）（図３点線部参照）。
【００３１】
また、一缶二水路式燃焼装置での熱交換比率は水（湯）の温度が高い側ほど低いので、風呂側缶体部１ｂに流れる湯の熱交換比率も温度が高くなるにつれて低くなる。よって、給湯湯温の少量の上昇（追い焚き循環管路側の短時間での上昇）後は、風呂側缶体部１ｂに流れる湯が熱交換する熱量は次第に少なくなり湯温の上昇速度が落ちる。そして、最終的に熱交換が行われなくなる所定の温度Ｔｃ（例えば８０度）に達する。
【００３２】
そこで、風呂側缶体部１ｂに流れる湯の温度が、上記所定温度Ｔｃに達するまでの間、熱交換される熱量の減少に合わせてバーナーの燃焼により与えられる熱量を減少させるためにガス供給量を徐々に減少させる。即ち、図３（ｃ）に示すように、ガス比例弁２５の開度を所定の開度（例えば、開度８０％から４０％）まで徐々に絞る（ステップＳ３）。従って、フィードバック制御にて給湯側出湯温度センサ１１が検出する温度に従って、ガス比例弁２５の開度が徐々に絞られるよう制御を行っても、十分追従時間をとることができる。
【００３３】
上記制御は、具体的には、制御装置２０に設けられたマイクロコンピュータ５０によって行われる。図６は、このマイクロコンピュータ５０の概略ブロック図を示す。マイクロコンピュータ５０には、ＣＰＵ５２、ＲＡＭ５３及びＲＯＭ５４がバス５５を介して接続されている。リモコン２１などからの指令信号及び給湯側出湯サーミスタ１１からの出力信号がマイクロコンピュータ５０のインターフェース５１を介して入力されると、上述のフローに従って、三方弁１８、ガス比例弁２５及び後述するようにポンプ１５に制御信号が出される。
【００３４】
このように、風呂追い焚きの停止指令が出されたときに、循環ポンプ１５を止めず、風呂側缶体部１ｂ内に湯に熱交換をさせながら、ガス比例弁２５の開度を徐々に小さくすることにより、給湯側缶体部１ｂに流れる湯に与えられる熱量が一定に保たれ、給湯温度を一定に維持することができる。
【００３５】
また、このとき、循環ポンプ１５の下流位置もしくは三方弁１８の上流位置にバッファタンク（図１における点線部４０）を設け、風呂側缶体部１ｂに流れる湯の温度上昇を緩慢にすることにより、風呂側缶体部１ｂに流れる湯の温度上昇が上述の場合より遅くなる。これにより、上述のガス比例弁２５をより時間をかけてきめ細かく調節することができるので、給湯温度をさらに正確に一定に保つことができるようになる。
【００３６】
そして、風呂側缶体部１ｂ内の湯の温度が一定温度Ｔｃに達すると（ステップＳ４）、風呂側缶体部１ｂ内の湯はこれ以上熱交換を行わないので、ガス比例弁２５の開度はその時点での開度に設定され、さらに、循環ポンプ１５が止められる（ステップＳ５）。この状態は、給湯側缶体部１ｂにのみ水が流れており、給湯単独使用状態である。
【００３７】
次に、この給湯単独使用状態において、風呂追い焚き指令がリモコン２１などにより出されると、本発明の第二の実施の形態によって、給湯温度は以下のように制御される。
【００３８】
図５のステップＳ６以降には、本実施の形態の動作を示すフローチャートが示される。さらに、図４は、本実施の第二の実施の形態における、（ａ）給湯側缶体部１ａ内の水の温度、（ｂ）風呂側缶体部１ｂ内の水の温度、（ｃ）ガス比例弁２５の開度、（ｄ）循環ポンプ１５及び（ｅ）三方弁１８の状態を示すグラフである。
【００３９】
図５のステップＳ６において、追い焚き指令が出された場合、ステップＳ７において、三方弁１８の状態は上述の図２における位置Ｂのまま、循環ポンプ１５を駆動させる（図４（ｄ）参照）。即ち、風呂側缶体部１ｂに流れる湯はすべてバイパス管１９を通り再度風呂側缶体部１ｂに入る。このとき、このバイパス管１９を経由して流れる湯は比較的少量であり、バイパス管１９経由で循環させることにより、この循環する水（湯）はほぼ均一な温度となるが、これを加熱するために必要な熱量は小さい。従って、図４（ａ）に示すように、給湯側出湯温度センサ１１による比例弁２５の開度調整制御追従範囲内なので、給湯温度の変化はない。
【００４０】
そして、図４（ｅ）に示すように、風呂側缶体部１ｂに流れ込むバイパス管１９を流れる湯全部が所定の一定温度Ｔｃになるまでの所定時間ｔ₂の経過後（ステップＳ８）、三方弁１８を図２における位置Ｂから位置Ａに所定時間ｔ₃かけて徐々に調節する。位置Ｂから位置Ａに調節されるにつれて、浴槽１４からの水（湯）の割合がバイパス管１９からの水（湯）の割合より大きくなるので、図４（ｂ）に示すように、風呂側缶体部１ｂに流れ込む水（湯）の温度は徐々に下がる。これに伴って、この温度が低下した風呂側缶体部１ｂに流れ込む水（湯）を所定の設定温度まで加熱するために、比例弁２５の開度を徐々に開き、バーナーの燃焼量を増大させる。
【００４１】
このとき、この風呂側缶体部１ｂに流れ込む水（湯）の温度の変化量は、上記したように、フィードバック制御による比例弁２５の開度制御によって給湯温度を変化させない範囲内の前記上限変化量θ’より大きくならないように、三方弁１８の駆動時間が制御される。そして、給湯温度を変化させない範囲で、風呂側缶体部１ｂに流れ込む水（湯）を所定の設定温度まで加熱するのに必要な熱量を与えるべく、図４（ｄ）に示すように、ガス比例弁２５の開度を制御する（ステップＳ９）。
【００４２】
具体的には、上述した図６において、制御装置２０に設けられたマイクロコンピュータ５０が、フィードバック制御にて給湯側出湯サーミスタ１１が検出する温度に従って、三方弁１８の駆動時間及びガス比例弁２５の開度を制御する。
【００４３】
このように、風呂側缶体部１ｂに流れ込む水（湯）の温度を徐々に低くし、その温度変化に応じた熱量をガス比例弁２５の開度の制御によって与えることにより、給湯側缶体部１ａ内を流れる湯に与える熱量を減少させることなく、風呂追い焚きを行うことができ、給湯温度はほぼ一定に保たれる。
【００４４】
最終的に、三方弁１８が位置Ａの状態に達すると（ステップＳ１０）、風呂側缶体部１ｂに流れ込む水（湯）の温度はこれ以上下がらないので、ガス比例弁２５の開度はその時点の開度に設定され（ステップＳ１１）、給湯と風呂追い焚きの同時使用状態となる。
【００４５】
また、本発明の実施の形態においては、三方弁１８を用いて上記の通り説明したが、本発明においては、三方弁に限られず、図７に示すような流量比率を変えられる機能を有する手段であれば、それを用いることが可能である。図７によれば、モータ６０が取り付けられたシャフト６１が、そのモータ６０の回転により図中左右に移動する。シャフト６１の移動により、シャフト６１に取り付けられた２つの係合部材６２と出口側追い焚き循環管路１３ｂ及びバイパス管１９にそれぞれ設けられた突出部６３との位置関係が調節され、両管６２及び６３への流量の比率を任意に設定することが可能となる。
【００４６】
【発明の効果】
以上説明したとおり、本発明によれば、一缶二水路式燃焼装置において、給湯と風呂追い焚きの同時使用状態の場合に、風呂追い焚きの停止指令が出されて、風呂側缶体部に流れる湯の循環が止められたとき、及び、給湯単独使用状態の場合に、風呂追い焚き指令が出されて、風呂側缶体部に湯が循環し始めたときに、給湯側缶体部内に流れる湯の温度をほぼ一定に保つことができる。
【図面の簡単な説明】
【図１】本発明の実施の形態における一缶二水路式燃焼装置の概略構成図である。
【図２】三方弁１８を説明するための図である。
【図３】本発明の第一の実施の形態における、（ａ）給湯側缶体部内の水の温度、（ｂ）風呂側缶体部内の水の温度、（ｃ）ガス比例弁２５の開度、（ｄ）循環ポンプ１５、（ｅ）三方弁１８の状態を示すグラフである。
【図４】本発明の第二の実施の形態における、（ａ）給湯側缶体部内の水の温度、（ｂ）風呂側缶体部に流れ込む水の温度、（ｃ）ガス比例弁２５の開度、（ｄ）循環ポンプ１５、（ｅ）三方弁１８の状態を示すグラフである。
【図５】本発明の実施の形態の動作を示すフローチャートである。
【図６】制御装置に設けられたマイクロコンピュータのブロック図である。
【図７】三方弁に代わって、流量比率を変えることができる手段の例である。
【符号の説明】
１缶体
１ａ給湯側缶体部
１ｂ風呂側缶体部
１３ａ入口側追い焚き循環管路
１３ｂ出口側追い焚き循環管路
１５循環ポンプ
１８三方弁
１９バイパス管
２０制御装置
２５ガス比例弁[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a single-can two-water channel combustion apparatus in which a hot water supply channel and a bath retreat channel pass through a single heat exchanger.
[0002]
[Prior art]
Conventionally, in a so-called single can two-channel combustion apparatus, when hot water is being supplied, that is, when the burner burns and water flows into the hot water supply side can body part, a reheating instruction for the bath is issued. When the circulation pump is driven and water flows into the bath-side can body, the bath chasing is started, and when both hot water supply and bath chasing are performed, a chasing stop command is issued. By stopping the circulation pump and stopping the flow of water to the bath-side can body, bathing was stopped.
[0003]
[Problems to be solved by the invention]
However, if a reflow command is issued during hot water supply, if water flows into the bath-side can body part, the amount of heat generated by combustion of the burner used to heat the water flowing through the hot-water side can body part until now A part of is used for heating the water flowing in the bath-side can body. Therefore, the amount of heat for heating the water flowing through the hot water supply side can body part to a predetermined set temperature is insufficient, and the hot water supply temperature is lowered. At this time, for example, after detecting the temperature drop of the hot water temperature detected by the hot water temperature thermistor, the supply gas amount is increased so that the heat flowing to the hot water side can body part is heated to a predetermined temperature. Although the combustion control is performed, a temporary change in the hot water supply temperature is inevitable.
[0004]
Further, when hot water supply and bath reheating are performed at the same time, the flow of water flowing through the bath side can body portion is stopped by issuing a bath retreat stop command. Therefore, the amount of heat that is greater than the amount of heat necessary to heat the water flowing to the hot water supply side can body part to a predetermined temperature is given, and the hot water supply temperature rises to a set temperature or higher. At this time, as described above, for example, after detecting the temperature rise of the hot water supply temperature detected by the hot water supply temperature thermistor, an amount of heat for heating the water flowing in the hot water supply side can body portion to a predetermined set temperature is given. Although combustion control for reducing the amount of supplied gas is performed, a temporary change in hot water supply temperature is inevitable.
[0005]
Therefore, the present invention is such that the hot water supply temperature is kept constant when bath reheating is started during hot water supply, and when bath reheating is stopped during simultaneous use of hot water supply and bath reheating. The purpose is to.
[0006]
[Means for Solving the Problems]
An object of the present invention is a one-can two-water channel combustion apparatus provided with a can consisting of a hot water supply side can body portion for performing hot water supply and a bath side can body portion for performing bath reheating,
A first conduit connected to the outlet side of the bath-side can body;
A second conduit connected to the entrance side of the bath-side can body part;
A pump that is provided in the second conduit and sends water to the bath-side can body;
A bypass pipe branched from the first pipe and connected to the second pipe upstream of the pump;
A combustion apparatus comprising: a valve capable of distributing a flow rate of water flowing through the first pipe before branching to the bypass pipe and the first pipe after branching at an arbitrary ratio. Is achieved by providing
[0007]
In addition, when a bath replenishment stop command is issued while hot water supply and bath replenishment are performed at the same time, almost all of the flow rate flowing through the first pipe before branching the valve is supplied to the bypass pipe. The combustion apparatus is controlled by operating to distribute and gradually decreasing the amount of heat applied to the can body.
[0008]
It is preferable that the amount of heat given to the can body is reduced according to the temperature of the water flowing through the hot water supply side can body portion.
[0009]
Also, when the temperature of the water flowing through the bath-side can body portion reaches a predetermined temperature, that is, when the water flowing through the bath-side can body portion no longer performs heat exchange, the pump operation is stopped. As described above, the combustion apparatus is controlled.
[0010]
In addition, when only a hot water supply is performed, if a bath rebirth command is issued, the pump is operated, and almost all of the flow rate of the flow through the first pipe before branching the valve is reduced to the bypass pipe. The combustion apparatus is controlled by operating from the state of distributing to the first pipe line after branching to the state of distributing to the first pipe and gradually increasing the amount of heat applied to the can body.
[0011]
It is preferable that the amount of heat given to the can body is increased according to the temperature of water flowing through the hot water supply side can body portion.
[0012]
Moreover, after the temperature of the water flowing through the bath side can body part reaches a predetermined temperature, the combustion apparatus may be controlled so that the operation of the valve and the amount of heat given to the can body are increased.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the technical scope of the present invention is not limited to this embodiment.
[0014]
FIG. 1 is a schematic configuration diagram of a single can two-water channel combustion apparatus according to an embodiment of the present invention. In FIG. 1, the can body 1 includes a hot water supply side can body portion 1 a and a bath side can body portion 1 b, and shares the fins 2. The can 1 is heated by the burner 3, and fuel gas is supplied to the burner 3 from the gas supply passage 4. The gas supply passage 4 is provided with a gas solenoid valve 24 for opening and closing the gas supply passage 4 and a gas proportional valve 25 for adjusting the gas supply amount. On the upper surface side of the burner 2, an igniter electrode 5 for igniting the burner 2 and a frame rod electrode 6 for detecting a flame are provided.
[0015]
A water supply pipe 7 that functions as a water supply passage for supplying water to the hot water supply side can body part 1a is connected to the inlet side of the hot water supply side can body part 1a. A water supply side incoming water temperature sensor 8 for detecting the temperature of the water supplied to the hot water supply side and a hot water supply side water amount sensor 9 for detecting the flow rate of the water supplied to the hot water supply side can body portion 1a are provided. A hot water supply pipe 10 through which hot water heated by the hot water supply side can body portion 1a is discharged is connected to the outlet side of the hot water supply side can body portion 1a and led to a desired place such as a kitchen. The hot water supply pipe 10 is provided with a hot water supply side hot water temperature sensor 11 for detecting the temperature of hot water discharged from the hot water supply side can body portion 1a.
[0016]
On the other hand, the bath side can body portion 1b is connected to the inlet side recirculation conduit 13a and the outlet side recirculation conduit 13b on the inlet side and the outlet side, respectively. 13 a and b are connected to the bathtub 14. In addition, a circulation pump 15 is provided in the inlet-side recirculation circulation line 13a, and the operation of the circulation pump 15 allows hot water in the bathtub 14 to be sent to the bath-side can body portion 1b. . Furthermore, a bath-side incoming temperature sensor 16 and a bath-side water amount sensor 17 are attached to the downstream side of the circulation pump 15.
[0017]
In addition, a control device 20 is provided in the one-can two-water channel combustion device, and a remote controller 21 is connected to the control device 20. The control device 20 performs hot water supply and reheating combustion control in accordance with an instruction from the remote controller 21 and the like. For example, when the hot water tap 28 is opened in a kitchen or the like, water flows into the water supply pipe 7 and is detected by the hot water supply side incoming water sensor 9. When the control device 20 receives the incoming water detection signal from the hot water supply side water amount sensor 9, the gas electromagnetic valve 24 and the gas proportional valve 25 in the gas supply passage 4 are opened, the igniter electrode 5 is discharged and ignited, and the frame rod electrode 6 After detecting the flame, the opening degree of the gas proportional valve 25 is controlled so that the hot water temperature detected by the hot water temperature sensor 11 becomes the set temperature set by the remote controller 21. By such control, hot water having a set temperature set by the remote controller 21 is supplied from the hot water supply pipe 10 to a desired place such as a kitchen.
[0018]
When the reheating operation is instructed by the remote controller 21 or the like, the control device 20 drives the circulation pump 15 of the recirculation circulation line 13 to replenish water (hot water) in the bathtub 14 and recirculate the circulation line 13. Circulate through. When the bath-side water amount sensor 17 detects the flow of water (hot water), the control device 20 opens the gas electromagnetic valve 24 and the gas proportional valve 25 in the gas supply passage 4, burns the burner 2 by ignition, and the bath-side can. The circulating hot water passing through the body 1b is heated to replenish water (hot water) in the bathtub 14. The chasing operation is stopped when the bath temperature detected by the bath-side hot water temperature sensor 22 reaches the bath set temperature set by the remote controller 21.
[0019]
Moreover, in the one-can two-water channel combustion apparatus according to the present invention, the three-way valve 18 bypasses the bathtub 14 for a part or all of the hot water discharged from the bath-side can body portion 1b, and the bath-side can body portion 1b. A bypass pipe 19 connected from the hot water outlet side to the upstream side of the circulation pump 15 is provided. The three-way valve 18 can distribute the flow rate from the outlet side of the bath-side can body portion 1b to the bathtub 14 and the bypass pipe 19 at an arbitrary ratio.
[0020]
FIG. 2 is a view for explaining the three-way valve 18. FIG. 2 (a) is a block diagram of the three-way valve 18. The three-way valve 18 includes a pipe portion 181 provided with one water inlet passage and two water outlet passages I and II, and a rotating body portion 182 rotated by a motor (not shown). The 2B and 2C are a side view and a cross-sectional view of the rotating body portion 182, respectively. According to these drawings, the rotating body portion 182 is provided with a plurality of holes having different cross-sectional areas on the side surface of the rotating body portion 182 for flowing water flowing into the outlet passages I and II. These holes are arranged so that the sum of the cross-sectional areas of the two holes facing the central axis of the rotating body 182 is constant.
[0021]
Therefore, by rotating the rotating body 182 relative to the pipe portion 181 and positioning it at an arbitrary position, the water from the water inlet passage can be distributed to the two water outlet passages I and II at an arbitrary flow rate ratio. For example, as shown in FIG. 2D, when the rotating body 182 is positioned at the position (1) in FIG. 2C with respect to the water discharge passages I and II, the same amount, that is, the flow ratio I: II = When 0.5: 0.5 water flows into the water discharge passages I and II and is positioned at the position (2), the flow rate ratio flowing through the two water discharge passages I and II is I: II = 0.1: 0.9.
[0022]
Further, in FIG. 2D, when the three-way valve 18 is in the state A, it is shown in FIG. 1 that all the hot water discharged flows into the bathtub 14 and does not flow into the bypass pipe 19. Furthermore, when it is in the state of B, it indicates that all of the hot water discharged flows into the bypass pipe 19 and does not flow into the bathtub 14.
[0023]
Now, in the combustion apparatus as described above, when both hot water supply and reheating of the bath are performed, hot water flows through the bath-side can body portion 1b by driving the circulation pump 15. At this time, the three-way valve 18 is adjusted so that all the hot water discharged from the bath side can body portion 1 b flows into the bathtub 14 and does not flow into the bypass pipe 19. That is, it is in the state A in FIG. At this time, when the bath reheating stop command is issued by the remote controller 21 or the like, as described above, conventionally, the circulation pump 15 is stopped, and the heat exchange amount in the bath-side can body portion 1b is rapidly reduced, so that the hot water supply temperature However, in the present invention, the hot water supply temperature is controlled by the first embodiment described below.
[0024]
FIG. 5 is a flowchart for explaining the operation of the embodiment of the present invention. Further, FIG. 3 shows the temperature of water in the hot water supply side can body portion 1a in the first embodiment of the present invention. (B) It is a graph which shows the temperature of the water in the bath side can body part 1b, (c) Gas proportional valve 25 opening degree, (d) Circulation pump 15 and (e) Three-way valve 18 state.
[0025]
First, in step S1 in FIG. 5, when a renewal stop command is issued, in step S2, the position of the three-way valve 18 is adjusted from the state A in FIG. 2 to the state B (see the solid line portion in FIG. 3 (e)). . Thereby, the flow to the bathtub 14 is stopped, and all the hot water discharged from the bath side can body portion 1 b flows to the bypass pipe 19. On the other hand, as shown in FIG. 3D, the circulation pump 15 does not stop for a predetermined time t ₁ that is the first time, and continues flowing hot water to the bath-side can body portion 1 b via the bypass pipe 19. As a result, since the hot water heated in the bathtub 14 does not circulate, the reheating to the bathtub hot water stops, but the hot water continues to flow in the bath-side can body portion 1b. Since the heat exchange continues, the amount of heat given to the hot water supply side can body portion 1b does not substantially change and the water temperature in the hot water supply side can body portion 1a remains constant as shown by the solid line portion in FIG. Kept.
[0026]
Explaining in detail this point, the hot water flowing through the bypass pipe 19 continues to change from a small amount to a total amount according to the driving time of the three-way valve 18, and as shown in FIG. The hot water temperature rises. Accordingly, although the amount of heat given to the hot water supply side can body 1a increases, it is the amount of temperature change (per unit time) within the opening adjustment (feedback) control follow-up range of the proportional valve 25 by the hot water supply side hot water thermistor 11, so FIG. As shown in (a), there is no change in the hot water supply temperature.
[0027]
When the driving of the three-way valve 18 is completed and the total amount of hot water flowing through the recirculation circulation lines 13a, b passes through the bypass pipe 19, the temperature of the hot water flowing through the recirculation circulation lines 13a, b in a relatively short time. Rises. Along with this, the amount of heat given to the hot water supply side can body portion 1a increases, and until the opening degree adjustment of the proportional valve 25 is performed by the hot water supply hot water temperature detection by the hot water supply side hot water supply thermistor 11 (this is feedback control). A small increase in hot water supply temperature due to the time lag ΔX.
[0028]
More specifically, as shown in FIG. 3 (b), the small increase in the hot water temperature is caused when the amount of temperature change in the bath-side can 1a controls the opening degree of the proportional valve 25 by feedback control. When the change amount θ is larger than the upper limit change amount θ ′ within a range where the hot water temperature does not change, the change amount θ is detected by the hot water supply side hot water thermistor 11 until the feedback control is performed. Caused by a delay. In FIG. 3B, when the change amount θ falls within the upper limit change amount θ ′ after X hours, the proportional valve 25 corresponding to the change amount θ is controlled at X ′ time after ΔX time elapses. During the + X ′ time, the hot water temperature slightly changes as shown in FIG. Thereafter, the hot water supply temperature is returned to and maintained at the set temperature.
[0029]
When the temperature of the hot water supply rises, control is started in advance so that the opening degree of the proportional valve 25 is reduced by driving the three-way valve 18 from the position A to the position B. As shown in FIG. 3 (b), the temperature change amount Y per unit time due to the stoppage of driving of the conventional pump is Y ′ in the present application as shown in FIG. 3B, but the influence on the hot water supply temperature is less than this value. . Even a small increase in the hot water supply temperature described above can be eliminated by controlling the driving time of the three-way valve 18 or providing a buffer tank described later.
[0030]
The method for controlling the driving time of the three-way valve 18 is to control the driving time from the position A to the position B so that the temperature of the hot water supply water does not change and is within the range of follow-up adjustment (feedback) control of the proportional valve 25. do it. In this case, driving of the three-way valve 18 is started from a temperature lower by a predetermined amount than the bath set temperature of the remote controller 21 (position A), and is stopped when the bath set temperature of the remote controller 21 is reached (position B) (FIG. 3). (See dotted line).
[0031]
In addition, since the heat exchange ratio in the single can two-water channel combustion apparatus is lower as the temperature of the water (hot water) is higher, the heat exchange ratio of the hot water flowing through the bath-side can body portion 1b also decreases as the temperature increases. Therefore, after a small increase in hot water temperature (a short time increase on the recirculation circulation line side), the amount of heat exchanged by the hot water flowing through the bath side can body portion 1b gradually decreases and the rate of increase in the hot water temperature decreases. . And finally, it reaches a predetermined temperature Tc (for example, 80 degrees) at which heat exchange is not performed.
[0032]
Therefore, in order to reduce the amount of heat provided by the burner combustion in accordance with the decrease in the amount of heat exchanged until the temperature of the hot water flowing through the bath-side can body portion 1b reaches the predetermined temperature Tc, the gas supply amount Reduce gradually. That is, as shown in FIG. 3C, the opening degree of the gas proportional valve 25 is gradually reduced to a predetermined opening degree (for example, 80% to 40% opening degree) (step S3). Therefore, even if control is performed so that the opening degree of the gas proportional valve 25 is gradually reduced according to the temperature detected by the hot water supply side hot water temperature sensor 11 by feedback control, a sufficient follow-up time can be taken.
[0033]
Specifically, the above control is performed by a microcomputer 50 provided in the control device 20. FIG. 6 shows a schematic block diagram of the microcomputer 50. A CPU 52, a RAM 53, and a ROM 54 are connected to the microcomputer 50 via a bus 55. When a command signal from the remote control 21 or the like and an output signal from the hot water supply side hot water thermistor 11 are input via the interface 51 of the microcomputer 50, the three-way valve 18, the gas proportional valve 25 and the following will be described in accordance with the above flow. A control signal is output to the pump 15.
[0034]
In this way, when the bath refueling stop command is issued, the opening of the gas proportional valve 25 is gradually increased while the circulation pump 15 is not stopped and the hot water is exchanged in the bath-side can body portion 1b. By making it small, the amount of heat given to the hot water flowing through the hot water supply side can body portion 1b is kept constant, and the hot water supply temperature can be kept constant.
[0035]
Further, at this time, by providing a buffer tank (dotted line portion 40 in FIG. 1) at the downstream position of the circulation pump 15 or the upstream position of the three-way valve 18, the temperature rise of the hot water flowing into the bath side can body portion 1b is slowed down. The temperature rise of the hot water flowing through the bath-side can body portion 1b is slower than in the above case. Thereby, since the above-mentioned gas proportional valve 25 can be finely adjusted over time, the hot water supply temperature can be kept more accurately and constant.
[0036]
When the temperature of the hot water in the bath-side can body portion 1b reaches a certain temperature Tc (step S4), the hot water in the bath-side can body portion 1b does not exchange any more heat, so that the gas proportional valve 25 is opened. The degree is set to the opening degree at that time, and further, the circulation pump 15 is stopped (step S5). This state is a state where water is flowing only in the hot water supply side can body portion 1b and the hot water supply is used alone.
[0037]
Next, in this hot water supply single use state, when a bath rebirth command is issued by the remote controller 21 or the like, the hot water supply temperature is controlled as follows according to the second embodiment of the present invention.
[0038]
After step S6 in FIG. 5, a flowchart showing the operation of the present embodiment is shown. Further, FIG. 4 shows (a) the temperature of water in the hot water supply side can body portion 1a, (b) the temperature of water in the bath side can body portion 1b, and (c) in the second embodiment of the present invention. It is a graph which shows the opening degree of the gas proportional valve 25, the state of (d) circulation pump 15 and (e) three-way valve 18.
[0039]
In step S6 of FIG. 5, when a restocking command is issued, in step S7, the circulation pump 15 is driven with the state of the three-way valve 18 remaining at the position B in FIG. 2 described above (see FIG. 4D). . That is, all the hot water flowing through the bath side can body portion 1b passes through the bypass pipe 19 and enters the bath side can body portion 1b again. At this time, the amount of hot water flowing through the bypass pipe 19 is relatively small, and by circulating through the bypass pipe 19, the circulating water (hot water) has a substantially uniform temperature, but this is heated. The amount of heat required for this is small. Therefore, as shown in FIG. 4 (a), the hot water supply temperature does not change because it is within the range of follow-up adjustment control of the proportional valve 25 by the hot water supply side hot water temperature sensor 11.
[0040]
Then, as shown in FIG. 4 (e), after a predetermined time t ₂ has elapsed until all water flowing through the bypass pipe 19 to flow into the bath side can body portion 1b reaches a predetermined constant temperature Tc (step S8), and the three-way valve 18 to regulate gradually over a predetermined time t ₃ to the position a from the position B in FIG. As the ratio from the position B to the position A is adjusted, the ratio of the water (hot water) from the bathtub 14 becomes larger than the ratio of the water (hot water) from the bypass pipe 19, so that as shown in FIG. The temperature of the water (hot water) flowing into the can body portion 1b gradually decreases. Along with this, in order to heat the water (hot water) flowing into the bath-side can body portion 1b whose temperature has decreased to a predetermined set temperature, the opening of the proportional valve 25 is gradually opened to increase the combustion amount of the burner. Let
[0041]
At this time, the amount of change in the temperature of the water (hot water) flowing into the bath side can body portion 1b is, as described above, the upper limit change within a range in which the hot water supply temperature is not changed by the opening degree control of the proportional valve 25 by feedback control. The driving time of the three-way valve 18 is controlled so as not to be larger than the amount θ ′. And in order to give the calorie | heat amount required to heat the water (hot water) which flows into the bath side can body part 1b to predetermined | prescribed preset temperature in the range which does not change hot water supply temperature, as shown in FIG.4 (d), gas The opening degree of the proportional valve 25 is controlled (step S9).
[0042]
Specifically, in FIG. 6 described above, the microcomputer 50 provided in the control device 20 drives the three-way valve 18 and the gas proportional valve 25 according to the temperature detected by the hot water supply side hot water thermistor 11 by feedback control. Control the opening.
[0043]
In this way, by gradually lowering the temperature of the water (hot water) flowing into the bath side can body portion 1b and giving the amount of heat according to the temperature change by controlling the opening of the gas proportional valve 25, the hot water supply side can body The bath can be reheated without reducing the amount of heat given to the hot water flowing in the section 1a, and the hot water supply temperature is kept substantially constant.
[0044]
Finally, when the three-way valve 18 reaches the position A (step S10), the temperature of the water (hot water) flowing into the bath side can body portion 1b does not drop any further, so the opening of the gas proportional valve 25 is The opening at the time is set (step S11), and the hot water supply and bath reheating are simultaneously used.
[0045]
In the embodiment of the present invention, the three-way valve 18 is used as described above. However, the present invention is not limited to the three-way valve and has a function of changing the flow rate ratio as shown in FIG. If so, it can be used. According to FIG. 7, the shaft 61 to which the motor 60 is attached moves to the left and right in the drawing by the rotation of the motor 60. The movement of the shaft 61 adjusts the positional relationship between the two engaging members 62 attached to the shaft 61 and the protrusions 63 provided on the outlet side recirculation circulation pipe 13b and the bypass pipe 19, respectively. And the ratio of the flow rate to 63 can be set arbitrarily.
[0046]
【The invention's effect】
As described above, according to the present invention, in the single-can two-water channel combustion apparatus, in the case of simultaneous use of hot water supply and bath reheating, a bath retreat stop command is issued and the bath side can body portion is When the circulation of flowing hot water is stopped and when the hot water supply is used alone, when a bath replenishment command is issued and hot water begins to circulate in the bath side can body part, The temperature of the flowing hot water can be kept almost constant.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a single can / two water channel combustion apparatus according to an embodiment of the present invention.
FIG. 2 is a view for explaining a three-way valve 18;
FIG. 3 is a diagram illustrating (a) the temperature of water in the hot water supply side can body, (b) the temperature of water in the bath side can body, and (c) opening of the gas proportional valve 25 in the first embodiment of the present invention. It is a graph which shows the state of the degree, (d) Circulation pump 15, (e) Three-way valve 18.
FIG. 4 is a diagram illustrating (a) the temperature of water in the hot water supply side can body, (b) the temperature of water flowing into the bath side can body, and (c) the gas proportional valve 25 in the second embodiment of the present invention. It is a graph which shows a state of an opening degree, (d) circulating pump 15, and (e) three-way valve 18.
FIG. 5 is a flowchart showing the operation of the exemplary embodiment of the present invention.
FIG. 6 is a block diagram of a microcomputer provided in the control device.
FIG. 7 is an example of means capable of changing the flow rate ratio instead of the three-way valve.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Can body 1a Hot water supply side can body part 1b Bath side can body part 13a Inlet side reheating circulation line 13b Outlet side reheating circulation line 15 Circulation pump 18 Three-way valve 19 Bypass pipe 20 Control device 25 Gas proportional valve

Claims

Connected to the outlet side of the bath-side can body unit in a one-can two-water channel combustion apparatus having a can body composed of a hot-water supply side can body portion for performing hot water supply and a bath-side can body portion for performing bath reheating The first pipe line, the second pipe line connected to the inlet side of the bath side can body part, and the pump provided in the second pipe line for feeding water to the bath side can body part And a bypass pipe branched from the first pipeline and connected to the second pipeline upstream of the pump, and a flow rate of water flowing through the first pipeline before branching, A pipe and a valve that can be distributed to the first pipeline after branching in any ratio;
When a bath replenishment stop command is issued when hot water supply and bath replenishment are performed at the same time, almost all of the flow rate flowing through the first pipe before branching the valve is distributed to the bypass pipe is actuated as, accordingly, combustion device you characterized by gradually reducing the amount of heat applied to the can body.

The combustion apparatus according to claim 1 , wherein the amount of heat given to the can body is reduced according to a temperature of water flowing through the hot water supply side can body portion.

The combustion apparatus according to claim 2, wherein the operation of the pump is stopped when the temperature of water flowing through the bath-side can body portion reaches a predetermined temperature.

Connected to the outlet side of the bath-side can body unit in a one-can two-water channel combustion apparatus having a can body composed of a hot-water supply side can body portion for performing hot water supply and a bath-side can body portion for performing bath reheating The first pipe line, the second pipe line connected to the inlet side of the bath side can body part, and the pump provided in the second pipe line for feeding water to the bath side can body part And a bypass pipe branched from the first pipeline and connected to the second pipeline upstream of the pump, and a flow rate of water flowing through the first pipeline before branching, A pipe and a valve that can be distributed to the first pipeline after branching in any ratio;
When only a hot water supply is in progress, if a bath rebirth command is issued, the pump is operated and almost all of the flow rate flowing through the first pipe before branching the valve is distributed to the bypass pipe. It actuates from state to state to be distributed to the first conduit after branching to, combustion apparatus you said gradually increasing the amount of heat applied to the can body.

The combustion apparatus according to claim 4 , wherein an amount of heat given to the can body is increased according to a temperature of water flowing through the hot water supply side can body portion.

The combustion apparatus according to claim 5 , wherein the valve is operated and the amount of heat given to the can body is increased after the temperature of the water flowing through the bath side can body portion reaches a predetermined temperature.