JP3859822B2

JP3859822B2 - 1 can 2 water channel type water heater

Info

Publication number: JP3859822B2
Application number: JP20133897A
Authority: JP
Inventors: 良彦田中
Original assignee: 株式会社ガスター
Priority date: 1997-07-28
Filing date: 1997-07-28
Publication date: 2006-12-20
Anticipated expiration: 2017-07-28
Also published as: JPH1151472A

Description

【０００１】
【発明の属する技術分野】
本発明は、浴槽内の水の循環する追い焚き流路内の水と給水の通る給湯流路内の水の双方にバーナーからの熱を１つの熱交換器で伝える１缶２水路型給湯器であって、設定された湯量まで前記浴槽に湯張りする機能を備えたものに関する。
【０００２】
【従来の技術】
従来から、風呂の追い焚き機能を備えた給湯器には、予め設定された湯量（水位）になるよう浴槽へ湯張りを行うものがあり、このような給湯器では、浴槽内の残水量を調べ、目標水位まで湯張りするために要する注湯量を求めるようになっている。残水量の確認は、水位センサを用いるほか、次のような手法で行われている。
【０００３】
すなわち、湯張りを行う前に、一定時間、浴槽内の湯を追い焚きするとともに、追い焚きする前の水温と追い焚きした後の水温とをそれぞれ測定し、追い焚きによって加えた熱量と追い焚き前後の水温の差とから、残水量を演算で求めている。
【０００４】
浴槽内の残水の温度を測定するための温度センサは、通常、追い焚き流路内に設けられているので、追い焚きの前後に水温を測定するとき、追い焚き流路内の水温と浴槽内の水温とを一致させかつ平均化する必要がある。このため、水温を測定する前にポンプを所定時間駆動し、追い焚き流路を経由させて浴槽内の水を循環するようになっている。
【０００５】
また、近年、給湯器の快適性をより向上するため、給湯を一旦停止させた後一定時間内に給湯を再開したとき、設定温度から大幅な温度変動を起こすことなく、たとえば、設定温度±３度程度の温度範囲で出湯することのできる機能（Ｑ機能）を備えた給湯器が要望されている。
【０００６】
このようなＱ機能を満足させるため、給湯流路内の湯温が、所定の下限温度を下回ったとき、開栓されない状態のままでバーナーを燃焼させ、給湯流路内の湯温を一定温度範囲内に維持することが行われている。
【０００７】
【発明が解決しようとする課題】
ところで、給湯流路と風呂の追い焚き流路とを共通の熱交換器に導きバーナーで加熱する、いわゆる１缶２水路型の給湯器では、バーナーを燃焼させると、給湯流路内の水と追い焚き流路内の水の双方が加熱される。このような１缶２水路型給湯器に、熱量とそれを加える前後における水温の差とから残水量を求める機能とＱ機能の双方を設けると、追い焚き流路内の水温と浴槽内の水温とを一致させるためにポンプを駆動して追い焚き流路経由で浴槽内の水を循環させている間に、給湯流路内の湯温維持のためにバーナーが点火することがある。
【０００８】
特に、残水量確認のための追い焚きを行う前における循環動作中では、浴槽内の水温が低い場合が多いので、追い焚き流路を流れる水に熱を奪われて給湯流路内の湯温が低下し、湯温維持のためにバーナーが点火してしまう。
【０００９】
このように残水量確認のための循環動作中にＱ機能に基づくバーナーの燃焼があると、浴槽内の水に対し加えた総熱量が変化してしまうとともに、浴槽内の水温と追い焚き流路内の水温とを循環動作によって平均化し一致させることができなくなり、適正な検温を行うことができない。その結果、演算で求めた残水量に許容範囲を越える誤差が生じてしまうという問題があった。
【００１０】
本発明は、このような従来の技術が有する問題点に着目してなされたもので、追い焚き等によって加えた熱量とその前後における水温の差とに基づいて浴槽内の残水量を求める機能と、開栓直後からほぼ設定温度の湯を出湯するための保温機能の双方を備えつつ、残水量を的確に求めることのできる１缶２水路型給湯器を提供することを目的としている。
【００１１】
【課題を解決するための手段】
かかる目的を達成するための本発明の要旨とするところは、次の各項の発明に存する。
［１］浴槽（４０）内の水の循環する追い焚き流路（３１）内の水と給水の通る給湯流路（２１）内の水の双方にバーナー（１２）からの熱を１つの熱交換器（１３）で伝える１缶２水路型給湯器（１０）であって、設定された湯量まで前記浴槽（４０）に湯張りする機能を備えたものにおいて、
開栓されない状態下で前記バーナー（１２）を燃焼させて前記給湯流路（２１）内の水を所定温度範囲内に保温する保温制御部（５１）と、前記設定された湯量になるように前記浴槽（４０）へ湯張りを行うとき当該浴槽（４０）内の残水量を検出する残水量検出部（５１）と、前記保温制御部（５１）の指示に基づく前記バーナー（１２）の燃焼を阻止する燃焼阻止部（５１）とを有し、
前記残水量検出部（５１）は、前記浴槽（４０）内の水を所定時間追い焚きするかもしくは温度が既知の水または湯をつぎ足すとともに、その前後においてそれぞれ前記追い焚き流路（３１）を通じて前記浴槽（４０）内の水をポンプ（３２）で循環させてその水温を検温し、前記追い焚きによって加えた熱量もしくは前記つぎ足した水または湯の温度および量と前記追い焚きもしくは前記つぎ足しの前後に検温した前記追い焚き流路（３１）内の水温の差とを基にして前記浴槽（４０）内の残水量を求め、
前記燃焼阻止部（５１）は、少なくとも前記残水量検出部（５１）が前記浴槽（４０）内の水を所定時間追い焚きするかもしくは温度が既知の水または湯をつぎ足すことを行う前に前記追い焚き流路（３１）を通じて前記浴槽（４０）内の水を前記ポンプ（３２）で循環させて前記浴槽（４０）内の水温と追い焚き流路（３１）内の水温とを一致させてその水温を検温する動作を行っている間、前記保温制御部（５１）の指示に基づく前記バーナー（１２）の燃焼を阻止することを特徴とする１缶２水路型給湯器（１０）。
【００１２】
［２］浴槽（４０）内の水の循環する追い焚き流路（３１）内の水と給水の通る給湯流路（２１）内の水の双方にバーナー（１２）からの熱を１つの熱交換器（１３）で伝える１缶２水路型給湯器（１０）であって、設定された湯量まで前記浴槽（４０）に湯張りする機能を備えたものにおいて、
設定温度の湯が開栓後所定時間内に出湯されるよう開栓されない状態下で前記バーナー（１２）を燃焼させて前記給湯流路（２１）内の水を所定温度範囲内に保温する保温制御部（５１）と、前記設定された湯量になるように前記浴槽（４０）へ湯張りを行うとき当該浴槽（４０）内の残水量を検出する残水量検出部（５１）と、前記保温制御部（５１）の指示に基づく前記バーナー（１２）の燃焼を阻止する燃焼阻止部（５１）とを有し、
前記保温制御部（５１）は、前記給湯流路（２１）内の水温が所定の下限温度を下回ったとき前記バーナー（１２）を燃焼させて当該給湯流路（２１）内の水温を所定の温度範囲に維持し、
前記残水量検出部（５１）は、前記浴槽（４０）内の水を所定時間追い焚きするかもしくは温度が既知の水または湯をつぎ足すとともに、その前後においてそれぞれ前記追い焚き流路（３１）を通じて浴槽（４０）内の水をポンプ（３２）で循環させて前記浴槽（４０）内の水温と前記追い焚き流路（３１）内の水温とを一致させてからその水温を検温し、前記追い焚きによって加えた熱量あるいは前記つぎ足した水または湯の温度および量と前記追い焚きあるいは前記つぎ足しの前後に検温した追い焚き流路（３１）内の水温の差とを基にして前記浴槽（４０）内の残水量を求め、
前記燃焼阻止部（５１）は、前記残水量検出部（５１）が前記追い焚き流路（３１）を通じて前記浴槽（４０）内の水をポンプ（３２）で循環させて浴槽（４０）内の水温と追い焚き流路（３１）内の水温とを一致させその水温を検温する動作を行っている間に、開栓されない状態下で前記給湯流路（２１）内の水温が前記下限温度を下回っても前記バーナー（１２）が燃焼しないよう制御することを特徴とする１缶２水路型給湯器（１０）。
【００１３】
［３］前記燃焼阻止部（５１）は、少なくとも前記残水量検出部（５１）が前記浴槽（４０）内の水を所定時間追い焚きするかもしくは温度が既知の水または湯をつぎ足すことを行う前に前記追い焚き流路（３１）を通じて前記浴槽（４０）内の水を前記ポンプ（３２）で循環させて前記浴槽（４０）内の水温と追い焚き流路（３１）内の水温とを一致させてその水温を検温する間、前記バーナー（１２）の燃焼を阻止することを特徴とする［２］記載の１缶２水路型給湯器（１０）。
【００１４】
前記本発明は次のように作用する。
残水量検出部（５１）は、浴槽（４０）内の水を所定時間追い焚きするかもしくは温度が既知の水または湯をつぎ足すとともに、その前後においてそれぞれ追い焚き流路（３１）を通じて浴槽（４０）内の水をポンプ（３２）で循環させて当該浴槽（４０）内の水温と追い焚き流路（３１）内の水温とを一致させてからその水温を検温する。そして、追い焚きによって加えた熱量もしくはつぎ足した水または湯の温度および量と、追い焚きもしくはつぎ足しの前後に検温した追い焚き流路（３１）内の水温の差とを基にして浴槽（４０）内の残水量を求める。
【００１５】
燃焼阻止部（５１）は、残水量検出部（５１）が追い焚き流路（３１）を通じて浴槽（４０）内の水をポンプ（３２）で循環させて浴槽（４０）内の水温と追い焚き流路（３１）内の水温とを一致させ、その水温を検温する動作を行っている間、保温制御部（５１）の指示に基づくバーナー（１２）の燃焼を阻止するよう動作する。
【００１６】
このように、検温に備えて浴槽（４０）内の水の循環しているとき、保温制御に基づいてバーナー（１２）の燃焼することがないので、当初の検温と後の検温の間に加えた熱量を的確に把握でき、かつ浴槽（４０）内と追い焚き流路（３１）内の水の温度を平均化して一致させ、的確な検温を行うことができる。その結果、残水量を演算によって少ない誤差で求めることができる。
【００１７】
また、少なくとも、追い焚き前に行う検温のための循環動作中、バーナー（１２）の燃焼を阻止するようにする。追い焚き前の循環では、浴槽（４０）内の水温が低いことが多いので、追い焚き流路（３１）を循環する水に熱を奪われて給湯流路（２１）内の湯温が低下し、湯温維持のためバーナー（１２）が点火してしまう場合が多い。一方、追い焚き後に行う検温のための循環では、追い焚き流路（３１）を通る湯温がある程度高くかつ直前まで追い焚きによって給湯流路（２１）側も加熱されるので、給湯流路（２１）内の湯温が低下し難く、湯温維持のためにバーナー（１２）の点火することが比較的少ない。
【００１８】
そこで、少なくとも追い焚き前の循環期間中に、湯温維持のためのバーナー（１２）の燃焼を阻止すれば、残水量の演算において大きな誤差の生じることを防ぐことができる。
【００１９】
【発明の実施の形態】
以下、図面に基づき本発明の一実施の形態を説明する。
各図は本発明の一実施の形態を示している。
本発明にかかる１缶２水路型の給湯器１０は、水栓あるいは風呂の浴槽内へ給湯する機能と、浴槽内の湯を追い焚きする機能とを備えている。図１に示すように、給湯器１０は、燃焼室１１を備えており、当該燃焼室１１の下部には、バーナー１２が、燃焼室１１の上部には、バーナー１２からの熱を給水等に伝える熱交換器１３がそれぞれ配置されている。
【００２０】
熱交換器１３には、給湯用の水を流すための給湯用パイプ２１と、追い焚き用に浴槽内の水を循環させる追い焚き用循環パイプ３１の双方が通っており、熱交換器１３はバーナー１２からの熱をこれら双方のパイプ２１、３１内の流体へ伝えて加熱する機能を備えている。
【００２１】
給湯用パイプ３１の熱交換器１３へ向かう給水側流路２１ａと、熱交換器１３からの出湯側流路２１ｂの間には、固定バイパス路２２と、流量制御弁２３の介挿されたバイパス路２４が接続されている。熱交換器１３で加熱された湯に、固定バイパス路２２、バイパス路２４を通じて給水を混合するとともに、バイパス比を、流量制御弁２３によって制御し得るようになっている。また、給湯用パイプ２１の出湯側流路２１ｂ側には、出湯の総流量やバイパス比を制御するための流量制御弁２５が設けられている。
【００２２】
給湯用パイプ２１の入口部および出口部の近傍にはそれぞれ、通水の有無や通水量を検知するためのフローセンサ２６ａ、２６ｂが設けられている。また、給湯用パイプ２１の入口部近傍には、給水の温度を検知するための入水サーミスタ２７が、熱交換器１３の出口部近傍には、加熱後の湯温を測定するための熱交サーミスタ２８が、さらに給湯用パイプ２１の出口部近傍には、出湯温度を検知するための出湯サーミスタ２９がそれぞれ取り付けられている。
【００２３】
追い焚き用循環パイプ３１は、浴槽４０内の水を熱交換器１３まで導く風呂戻パイプ部３１ａと、熱交換器１３で加熱後の湯を浴槽４０へ戻す風呂往パイプ部３１ｂとから構成されている。風呂戻パイプ部３１ａの途中には循環ポンプ３２と、風呂戻パイプ部３１ａ内の通水の有無を検知する風呂流水スイッチ３３が設けられている。また、風呂流水スイッチ３３の近傍には、浴槽４０側から流入する湯の温度を検知するための風呂温度サーミスタ３４が取り付けてある。
【００２４】
給湯用パイプ２１の出湯側流路２１ｂと、風呂戻パイプ部３１ａとは、注湯電磁弁３５を備えた注湯パイプ３６で接続されており、熱交換器１３で加熱された給水を注湯パイプ３６を介して浴槽４０へ注湯することができるようになっている。
【００２５】
給排気は、燃焼ファン１４によって燃焼室１１の下方側から給気を送風することによって強制的に行われ、排気は燃焼室１１の上部から排出されるようになっている。バーナー１２近傍には、図１では示していない点火装置１５が設けてある。またバーナー１２へ供給される燃焼ガスは、ガス電磁弁１６、元ガス電磁弁１７、ガス切替弁１８によってオンオフ制御される。さらにバーナー１２へ供給される燃焼ガスのガス量は、ガス比例弁１９によって調整される。
【００２６】
図２は、給湯器１０の有する制御基盤の回路構成を示したものである。給湯器１０の制御基盤は、各種制御の中枢的機能を果たすＣＰＵ（中央処理装置）５１を備えている。ＣＰＵ５１には、データバスやアドレスバスなど各種バス５２を介して各種の回路装置が接続されている。
【００２７】
このうち、ＲＯＭ（リード・オンリ・メモリ）５３は、ＣＰＵ５１の実行するプログラムや各種の固定的データを記憶する読み出し専用メモリである。ＲＡＭ（ランダム・アクセス・メモリ）５４は、プログラムを実行する上で、一時的に必要になるデータを記憶するための作業メモリである。
【００２８】
バス５２には、本体操作部５５のほか、各種回路装置とＣＰＵ５１との間で電気信号の入出力を行うための入出力インターフェイス回路部５６が接続されている。入出力インターフェイス回路部５６には、フローセンサ２６ａ、２６ｂ、各種サーミスタ２７〜２９、３４、点火装置１５、燃焼ファン１４、各種ガス制御弁１６〜１９、および流量制御弁２３、２５、注湯電磁弁３５および循環ポンプ３２を駆動するポンプ駆動回路３２ａが接続されている。このほか、必要に応じて各種制御装置が入出力インターフェイス回路部５６に接続される。
【００２９】
次に作用を説明する。
まず、出湯を開始した直後から出湯温度を、設定温度に対し許容温度範囲（±３℃）内に収まるよう給湯用パイプ２１内の湯を目標温度範囲に保温する機能（Ｑ機能）について説明する。ＣＰＵ５１は、熱交サーミスタ２８からの温度情報を基にして、給湯用パイプ２１の熱交換器１３部分に存在する湯の温度を検知している。出湯されない状態、すなわち、通水の無い状態の下で、熱交サーミスタ２８で検知される給湯用パイプ２１内の湯温が目標温度範囲の下限を下回ったとき、ＣＰＵ５１はバーナー１２を１秒から２秒の短時間点火し、給湯用パイプ２１内の湯温を目標温度範囲内に維持するよう動作する。
【００３０】
なお、このような保温動作を、前回の出湯が停止してから所定時間だけ行い、次回の出湯に備えるようにしても良いし、給湯器の運転中、常に保温動作を行うようにしてもよい。
【００３１】
次に、浴槽４０への自動湯張り動作について説明する。図３は、浴槽に湯張りを行う際の動作の流れを示している。本体操作部５５や図示しないリモコン操作部に設けてある風呂の自動運転スイッチがオンされると（ステップＳ１０１；Ｙ）、まず、浴槽４０内に存在する残水量の確認動作を行う（ステップＳ１０２）。なお、残水確認動作の詳細については後に説明する。
【００３２】
残水量確認によって求めた浴槽内の残水量が、予め設定されている湯張り完了時の湯量より少ないときは（ステップＳ１０３；Ｎ）、その差分を浴槽４０へ注湯すべき湯量として求め、当該量の湯を浴槽４０へ注湯する（ステップＳ１０４）。注湯終了後、あるいは当初から必要湯量があったときは（ステップＳ１０３；Ｙ）、浴槽内の湯温が、設定されている沸き上がり温度に達しているか否かを調べる（ステップＳ１０５）。
【００３３】
浴槽４０内の湯温が、設定温度より低いときは（ステップＳ１０５；Ｎ）、追い焚きを行い（ステップＳ１０４）、設定温度になったとき（ステップＳ１０５；Ｙ）、お知らせ音等を鳴らし、自動湯張りの動作を終了する（エンド）。
【００３４】
次に、残水量確認動作について説明する。残水量の確認は、一定時間の追い焚きを行う前後に、湯温を測定し、その温度差と追い焚きによって加えた熱量とを基にして次式で求める。
【００３５】
【数１】

【００３６】
ここで、Ｖは、浴槽内の残水量（リットル）、Ｉｓはインプット（Ｋｃａｌ／ｈｒ）、ｔは燃焼時間（ｈｒ）、ηは熱効率（％）、ｃは水の比熱（Ｋｃａｌ／Ｋｇ℃）、Ｔ１は追い焚き前の水温、Ｔ２は追い焚き後の水温をそれぞれ示している。
【００３７】
（１）式を基にして少ない誤差で残水量を求めるためには、風呂温度サーミスタ３４の検温する温度が、浴槽内の平均湯温を示していることが望ましい。また、当初の検温と後の検温の間に浴槽内の湯に加えた熱量をできるだけ正確に把握しておく必要がある。
【００３８】
ところで、通常、浴槽内は、追い焚き用循環パイプ３１内よりも保温状態が良いので、自動湯張りを開始する時点では、浴槽４０内の水温と追い焚き用循環パイプ３１内の水温は一致しないことが多い。そこで、残水量確認のための検温を行う前に、一定時間循環ポンプ３２を駆動して循環パイプ３１を通じて浴槽４０内の残水をかき混ぜ、追い焚き用循環パイプ３１に取り付けた風呂温度サーミスタ３４で浴槽４０内の平均湯温を検温できるようにしている。
【００３９】
また、循環ポンプ３２を駆動して浴槽内の水をかき混ぜている間に、Ｑ機能に基づくバーナー１２の燃焼が行われると、予期せぬ熱量が浴槽内の水に加わってるので、（１）式の演算で求まる残水量の誤差が大きくなってしまう。さらに、残水確認の際の水温は比較的低温であることが多いので、循環ポンプ３２で検温前に循環させると給湯用パイプ２１側の熱が追い焚き用循環パイプ３１を流れる水に奪われ、給湯用パイプ２１内の湯温が低下する。このため、循環ポンプ３２で浴槽内の水をかき混ぜている間に、湯温維持のための燃焼が行われる可能性が極めて高くなる。そこで、循環ポンプ３２で浴槽４０内の水を循環させはじめてから検温を終了するまでの間、バーナー１２の燃焼を強制的に阻止するようにしている。
【００４０】
図４は、自動湯張りの際に行う残水量確認動作の流れを示している。まず、Ｑ機能による保温動作によってバーナー１２が点火しないよう設定する（ステップＳ２０１）。実際には、ＲＡＭ５４の所定アドレスに、Ｑ機能に基づくバーナー１２の燃焼を禁止する旨の禁止フラグをセットする。
【００４１】
ＣＰＵ５１は、通水の無い状態で給湯用パイプ２１内の湯温が目標温度範囲の下限を下回ったとき、当該禁止フラグがセットされているか否かを確認し、禁止フラグがセットされていないときはバーナー１２を１〜２秒の短時間燃焼させる。一方、給湯用パイプ２１内の湯温が目標温度範囲の下限を下回った場合であっても、禁止フラグがセットされているときは、バーナー１２を点火しないよう制御する。
【００４２】
このように、Ｑ機能に基づくバーナー１２の燃焼を禁止した状態で、循環ポンプ３２を約３０秒間駆動した後（ステップＳ２０２）、風呂温度サーミスタ３４で浴槽４０内の水温（Ｔ１）を検温する（ステップＳ２０３）。また検温が終了した時点で、バーナー１２の燃焼を阻止する旨の禁止フラグをリセットする（ステップＳ２０４）。
【００４３】
次に、ＣＰＵ５１は、予め定めたインプットでバーナー１２を燃焼させるとともに循環ポンプ３２を駆動して、一定時間風呂の追い焚きを行う（ステップＳ２０５）。一定時間の追い焚きを完了したとき、このままの状態では追い焚き用循環パイプ３１内に熱い湯が残っているので、再び禁止フラグをセットしてＱ機能に基づくバーナー１２の燃焼を阻止した状態で（ステップＳ２０６）、循環ポンプ３２を約３０秒ほど駆動し、浴槽４０内と追い焚き用循環パイプ３１内の水温の平均化する（ステップＳ２０７）。
【００４４】
その後、検温を行って追い焚き後の浴槽内の水温（Ｔ２）を検知し（ステップＳ２０８）、（１）式から残水量を求める（ステップＳ２０９）。
【００４５】
このように、Ｑ機能に基づくバーナー１２の燃焼を禁止した状態で、循環ポンプ３２を動作させ浴槽４０と追い焚き用循環パイプ３１内の水を循環させかき混ぜるので、精度の高い検温と加えた熱量の的確な把握を行うことができ、（１）式によって残水量を少ない誤差で求めることができる。
【００４６】
検温のための循環中に蛇口が開栓され通水のあったときは、給湯側を優先させるため、バーナー１２を点火して燃焼を行うようになっている。この場合、残水確認のための循環動作は、通水が停止した後、改めて行っている。
【００４７】
なお、検温のための循環動作中に、Ｑ機能に基づくバーナー１２の燃焼を阻止せず、循環動作中にバーナー１２の燃焼があったとき、通水のあった場合と同様に、循環動作を後に改めて行うようにすることはできない。すなわち、追い焚き用循環パイプ３１を流れる水によって給湯用パイプ２１内の熱が奪われるので、Ｑ機能に基づくバーナー１２の燃焼停止後に循環動作を再開するとすぐに湯温が低下してバーナー１２の燃焼が再開してしまい、いつまでも検温できない状態が続くことになる。
【００４８】
以上説明した実施の形態では、残水量を確認する際、追い焚きによって浴槽内の水に所定の熱量を加えたが、温度が既知の水あるいは湯を注湯パイプ３６を介して浴槽４０内へ注ぎ、その前後における水温の差と、加えた水または湯の温度およびその量とから、残水量を求めることもできる。この場合でも、的確に浴槽内の平均水温を求めるために循環ポンプ３２で浴槽内の水を循環する必要があり、その際、Ｑ機能に基づくバーナー１２の燃焼を阻止するよう制御することは追い焚きにより加熱する場合と同様である。
【００４９】
また、実施の形態では、浴槽内に一定以上の残水があることを前提に説明したが、循環ポンプ３２を回しても、風呂流水スイッチ３３がオンしない場合には、浴槽４０内が「空」あるいは水位が極めて低いと判断し、風呂流水スイッチ３３がオンするまで水または湯を注湯し、その後改めて残水確認の動作を行うようにすればよい。
【００５０】
さらに、実施の形態では、追い焚き前の循環動作と追い焚き後の循環動作の双方においてＱ機能に基づくバーナー１２の燃焼を阻止するようにしたが、少なくとも追い焚き前の循環動作においてＱ機能に基づく燃焼を阻止すれば、残水量の誤差をある程度少なく維持することができる。
【００５１】
すなわち、追い焚き後は、浴槽内の水温が比較的高いので追い焚き用循環パイプ３１を循環する湯によって給湯用パイプ２１側の熱が奪われ難くなる。さらに、追い焚き動作によって給湯用パイプ２１も直前まで加熱されていたので、循環動作中に目標下限温度を下回る可能性はほとんどなく、敢えてＱ機能による燃焼を阻止しなくても良い。
【００５２】
【発明の効果】
本発明にかかる１缶２水路型給湯器によれば、出湯開始直後からほぼ設定温度の湯を出すために予め給湯流路内の湯を保温する動作に基づくバーナーの燃焼を、残水確認のための検温に備えて浴槽内の水を追い焚き流路を通じて循環させる間、阻止するようにしたので、残水確認用の追い焚き等で加えた熱量を的確に把握することができるとともに、浴槽内と追い焚き流路内の水の平均温度を的確に検温することができ、演算で求める残水量の誤差を少なく抑えることができる。
【図面の簡単な説明】
【図１】本発明の一実施の形態に係る１缶２路型給湯器を示す説明図である。
【図２】本発明の一実施の形態に係る１缶２水路型給湯器の有する制御基盤の回路構成を示すブロック図である。
【図３】本発明の一実施の形態に係る１缶２水路型給湯器が自動湯張りの際に行う動作の流れを示す流れ図である。
【図４】本発明の一実施の形態に係る１缶２水路型給湯器が自動湯張りの際に行う残水量確認動作の流れを示す流れ図である。
【符号の説明】
１０…給湯器
１２…バーナー
１３…熱交換器
２１…給湯用パイプ
２８…熱交サーミスタ
３１…追い焚き用循環パイプ
３２…循環ポンプ
３３…風呂流水スイッチ
３４…風呂温度サーミスタ
３５…注湯電磁弁
３６…注湯パイプ
４０…浴槽[0001]
BACKGROUND OF THE INVENTION
The present invention is a one-can two-water channel type water heater that transmits heat from a burner to both water in a reheating channel through which water in a bathtub circulates and water in a hot water flow channel through which the water is supplied with one heat exchanger. And it is related with what was equipped with the function to fill with water to the said bathtub to the set amount of hot water.
[0002]
[Prior art]
Conventionally, some water heaters that have a bath replenishment function are used to fill a bathtub with a preset amount of water (water level). With such a water heater, the amount of water remaining in the bathtub can be reduced. The amount of pouring required to fill the hot water up to the target water level is calculated. In addition to using a water level sensor, the remaining amount of water is checked by the following method.
[0003]
In other words, the hot water in the bathtub is chased for a certain period of time before filling, and the water temperature before chasing and the water temperature after chasing are measured, respectively, and the amount of heat added by chasing and chasing The amount of residual water is calculated from the difference in water temperature before and after.
[0004]
Since the temperature sensor for measuring the temperature of the remaining water in the bathtub is usually provided in the reheating channel, when the water temperature is measured before and after reheating, the water temperature in the reheating channel and the bathtub are measured. It is necessary to match and average the water temperature inside. For this reason, the pump is driven for a predetermined time before the water temperature is measured, and the water in the bathtub is circulated through the reheating channel.
[0005]
In recent years, in order to further improve the comfort of the water heater, when hot water supply is resumed within a certain time after the hot water supply is temporarily stopped, for example, the set temperature ± 3 There is a demand for a water heater having a function (Q function) that can discharge hot water in a temperature range of about 50 degrees.
[0006]
In order to satisfy such a Q function, when the hot water temperature in the hot water supply flow path falls below a predetermined lower limit temperature, the burner is burned without being opened, and the hot water temperature in the hot water supply flow path is kept at a constant temperature. It is done to keep within range.
[0007]
[Problems to be solved by the invention]
By the way, in a so-called one-can two-water channel type water heater in which the hot water supply channel and the reheating channel of the bath are led to a common heat exchanger and heated by a burner, when the burner is burned, Both water in the reheating channel is heated. If such a can / two-channel water heater is provided with both a function for determining the amount of remaining water from the amount of heat and the difference in water temperature before and after applying it and the Q function, the water temperature in the reheating channel and the water temperature in the bathtub In order to maintain the hot water temperature in the hot water supply flow path, the burner may ignite while the pump is driven to circulate the water in the bathtub via the reheating flow path.
[0008]
In particular, during the circulation operation before reheating to check the remaining water amount, the water temperature in the bathtub is often low, so the water flowing in the reheating channel is deprived of heat and the hot water temperature in the hot water supply channel is Decreases and the burner ignites to maintain the hot water temperature.
[0009]
In this way, if the burner burns based on the Q function during the circulation operation for checking the remaining water amount, the total amount of heat applied to the water in the bathtub changes, and the water temperature in the bathtub and the reheating channel The water temperature inside cannot be averaged and matched by the circulation operation, and proper temperature detection cannot be performed. As a result, there is a problem that an error exceeding the allowable range occurs in the residual water amount obtained by the calculation.
[0010]
The present invention has been made paying attention to such problems of the prior art, and has a function of determining the amount of residual water in the bathtub based on the amount of heat applied by reheating and the difference in water temperature before and after the heat. An object of the present invention is to provide a single can / two water channel type water heater capable of accurately obtaining the amount of remaining water while having both a heat retaining function for discharging hot water at substantially the set temperature immediately after opening.
[0011]
[Means for Solving the Problems]
The gist of the present invention for achieving the object lies in the inventions of the following items.
[1] Heat from the burner (12) is supplied to both the water in the reheating channel (31) through which water in the bathtub (40) circulates and the water in the hot water supply channel (21) through which the water is supplied. In the 1 can 2 water channel type water heater (10) transmitted by the exchanger (13), which has a function of filling the bathtub (40) to the set amount of hot water,
A heat retention control unit (51) for burning the burner (12) in a state where it is not opened to keep the water in the hot water supply channel (21) within a predetermined temperature range, and so as to have the set amount of hot water. Combustion of the remaining water amount detection unit (51) for detecting the remaining water amount in the bathtub (40) when filling the bathtub (40) and the burner (12) based on the instruction of the heat retention control unit (51) A combustion inhibiting part (51) for inhibiting
The residual water amount detecting unit (51), said tub (40) to or the temperature of water to reheating predetermined time with TOP UP known water or hot water in the respective said Reheating channel in its longitudinal (31) The water in the bathtub (40) is circulated by the pump (32) through the water and the temperature of the water is measured, and the amount of heat applied by the reheating or the temperature and amount of the added water or hot water and the reheating or adding seeking residual water content of the bath (40) based on the difference between the temperature of the reheating passages (31) in the thermometry back and forth,
Before the combustion preventing unit (51) performs at least the remaining water amount detecting unit (51) replenishing the water in the bathtub (40) for a predetermined time or adding water or hot water having a known temperature. is matched with the temperature of the reheating passages said bath (40) in the water temperature and reheating passages of the bath (40) is circulated by the pump (32) through (31) (31) in The one-can two-water heater (10) is characterized in that combustion of the burner (12) based on an instruction from the heat retention control unit (51) is prevented during an operation for detecting the water temperature.
[0012]
[2] Heat from the burner (12) is supplied to both the water in the reheating channel (31) through which water in the bathtub (40) circulates and the water in the hot water supply channel (21) through which the water is supplied. In the 1 can 2 water channel type water heater (10) transmitted by the exchanger (13), which has a function of filling the bathtub (40) to the set amount of hot water,
Insulation that keeps the water in the hot water supply passage (21) within a predetermined temperature range by burning the burner (12) in a state where the hot water at the set temperature is not opened so that the hot water is discharged within a predetermined time after opening. A control unit (51), a remaining water amount detection unit (51) for detecting a remaining water amount in the bathtub (40) when the hot water is filled in the bathtub (40) so as to have the set hot water amount, and the heat insulation A combustion blocking unit (51) for blocking combustion of the burner (12) based on an instruction from the control unit (51),
The heat retention control section (51) burns the burner (12) when the water temperature in the hot water supply channel (21) falls below a predetermined lower limit temperature, and sets the water temperature in the hot water supply channel (21) to a predetermined value. Keep in the temperature range,
The residual water amount detecting unit (51), said tub (40) to or the temperature of water to reheating predetermined time with TOP UP known water or hot water in the respective said Reheating channel in its longitudinal (31) The water in the bathtub (40) is circulated by the pump (32) through the water temperature in the bathtub (40) and the water temperature in the reheating channel (31), and the water temperature is detected, Based on the amount of heat applied by reheating or the temperature and amount of the added water or hot water and the difference in water temperature in the reheating channel (31) measured before and after the reheating or adding, the bathtub (40 )
The combustion prevention unit (51) is configured such that the residual water amount detection unit (51) circulates the water in the bathtub (40) with the pump (32) through the reheating channel (31), and the water in the bathtub (40). While the operation of detecting the water temperature by matching the water temperature with the water temperature in the reheating channel (31) is performed, the water temperature in the hot water supply channel (21) reaches the lower limit temperature in a state where the water temperature is not opened. 1 can 2 water channel type water heater (10) controlled so that the burner (12) does not burn even if it falls below.
[0013]
[3] The combustion prevention unit (51) causes at least the residual water amount detection unit (51) to replenish the water in the bathtub (40) for a predetermined time or add water or hot water having a known temperature. and temperature of the reheating passages (31) said tub (40) in the water temperature and reheating passages of the bath (40) is circulated by the pump (32) of (31) in the through before making 1, 2 canal type water heater (10) according to [ 2 ], wherein combustion of the burner (12) is prevented while the water temperature is detected.
[0014]
The present invention operates as follows.
The remaining water amount detection unit (51) replenishes the water in the bathtub (40) for a predetermined time or adds water or hot water having a known temperature, and before and after that, through the reflow channel (31), the bathtub ( The water in 40) is circulated by the pump (32) so that the water temperature in the bathtub (40) matches the water temperature in the reheating channel (31), and then the water temperature is detected. The bathtub (40) is based on the amount of heat applied by reheating or the temperature and amount of added water or hot water and the difference in water temperature in the reheating channel (31) measured before and after reheating or adding. Find the amount of water remaining in the tank.
[0015]
The combustion prevention unit (51) is configured to cause the remaining water amount detection unit (51) to circulate the water in the bathtub (40) with the pump (32) through the reheating channel (31) to recharge the water temperature in the bathtub (40). While performing the operation | movement which makes the water temperature in a flow path (31) correspond, and detects the water temperature, it operate | moves so that combustion of the burner (12) based on the instruction | indication of a heat retention control part (51) may be prevented.
[0016]
Thus, when the water in the bathtub (40) circulates in preparation for temperature measurement, the burner (12) does not burn based on the heat retention control, so it is added between the initial temperature measurement and the subsequent temperature measurement. The amount of heat generated can be accurately grasped, and the temperature of the water in the bathtub (40) and the reheating channel (31) can be averaged and matched to perform accurate temperature detection. As a result, the remaining water amount can be obtained with a small error by calculation.
[0017]
Further, at least during the circulation operation for temperature detection performed before reheating, combustion of the burner (12) is prevented. In the circulation before reheating, the water temperature in the bathtub (40) is often low, so the water circulating in the reheating channel (31) is deprived of heat and the hot water temperature in the hot water supply channel (21) decreases. In many cases, the burner (12) is ignited to maintain the hot water temperature. On the other hand, in the circulation for temperature detection performed after reheating, the hot water temperature passing through the reheating flow path (31) is somewhat high and the hot water supply flow path (21) side is also heated by reheating until just before the hot water supply flow path ( 21) It is difficult for the hot water temperature in the interior to decrease, and the burner (12) is ignited relatively little to maintain the hot water temperature.
[0018]
Therefore, if combustion of the burner (12) for maintaining the hot water temperature is prevented at least during the circulation period before reheating, it is possible to prevent a large error from occurring in the calculation of the remaining water amount.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
Each figure shows an embodiment of the present invention.
1 can 2 water channel type water heater 10 according to the present invention has a function of supplying hot water into a faucet or a bath tub and a function of chasing hot water in the tub. As shown in FIG. 1, the water heater 10 includes a combustion chamber 11, a burner 12 is provided at the lower part of the combustion chamber 11, and heat from the burner 12 is provided at the upper part of the combustion chamber 11 for supplying water or the like. A heat exchanger 13 for transmitting is arranged.
[0020]
Both the hot water supply pipe 21 for flowing hot water and the recirculation pipe 31 for circulating water in the bathtub for reheating pass through the heat exchanger 13. The heat from the burner 12 is transmitted to the fluid in both the pipes 21 and 31 and heated.
[0021]
Between the water supply side flow path 21 a toward the heat exchanger 13 of the hot water supply pipe 31 and the hot water supply side flow path 21 b from the heat exchanger 13, a bypass with a fixed bypass path 22 and a flow rate control valve 23 interposed. A path 24 is connected. The hot water heated by the heat exchanger 13 is mixed with the feed water through the fixed bypass passage 22 and the bypass passage 24, and the bypass ratio can be controlled by the flow control valve 23. In addition, a flow rate control valve 25 for controlling the total flow rate and bypass ratio of the hot water is provided on the hot water supply side flow passage 21b side of the hot water supply pipe 21.
[0022]

Flow sensors

26a and 26b for detecting the presence / absence of water flow and the amount of water flow are provided in the vicinity of the inlet and outlet of the hot water supply pipe 21, respectively. An inlet thermistor 27 for detecting the temperature of the supplied water is provided near the inlet of the hot water supply pipe 21, and a heat exchanger thermistor for measuring the hot water temperature after heating is provided near the outlet of the heat exchanger 13. In addition, a hot water thermistor 29 for detecting the hot water temperature is attached near the outlet of the hot water supply pipe 21.
[0023]
The recirculation pipe 31 is composed of a bath return pipe portion 31 a that guides water in the bathtub 40 to the heat exchanger 13, and a bath return pipe portion 31 b that returns hot water heated by the heat exchanger 13 to the bathtub 40. ing. In the middle of the bath return pipe portion 31a, a circulation pump 32 and a bath running water switch 33 for detecting the presence or absence of water flow in the bath return pipe portion 31a are provided. A bath temperature thermistor 34 for detecting the temperature of hot water flowing from the bathtub 40 side is attached in the vicinity of the bath water switch 33.
[0024]
The hot water supply side pipe 21b of the hot water supply pipe 21 and the bath return pipe portion 31a are connected by a pouring pipe 36 having a pouring solenoid valve 35, and the hot water supplied by the heat exchanger 13 is poured. Hot water can be poured into the bathtub 40 through the pipe 36.
[0025]
The supply / exhaust is forcibly performed by blowing the supply air from the lower side of the combustion chamber 11 by the combustion fan 14, and the exhaust is discharged from the upper part of the combustion chamber 11. An ignition device 15 not shown in FIG. 1 is provided in the vicinity of the burner 12. The combustion gas supplied to the burner 12 is on / off controlled by the gas solenoid valve 16, the original gas solenoid valve 17, and the gas switching valve 18. Further, the amount of combustion gas supplied to the burner 12 is adjusted by a gas proportional valve 19.
[0026]
FIG. 2 shows a circuit configuration of a control base included in the water heater 10. The control base of the water heater 10 includes a CPU (Central Processing Unit) 51 that performs a central function of various controls. Various circuit devices are connected to the CPU 51 via various buses 52 such as a data bus and an address bus.
[0027]
Among these, a ROM (Read Only Memory) 53 is a read only memory for storing a program executed by the CPU 51 and various kinds of fixed data. A RAM (Random Access Memory) 54 is a working memory for storing data that is temporarily required for executing a program.
[0028]
In addition to the main body operation unit 55, an input / output interface circuit unit 56 for inputting / outputting electric signals between various circuit devices and the CPU 51 is connected to the bus 52. The input / output interface circuit unit 56 includes

flow sensors

26a and 26b, various thermistors 27 to 29, 34, an ignition device 15, a combustion fan 14, various gas control valves 16 to 19, and flow

control valves

23 and 25, and a pouring electromagnetic valve. A pump drive circuit 32a for driving the valve 35 and the circulation pump 32 is connected. In addition, various control devices are connected to the input / output interface circuit unit 56 as necessary.
[0029]
Next, the operation will be described.
First, a function (Q function) for keeping the hot water in the hot water supply pipe 21 within the target temperature range so that the hot water temperature is within the allowable temperature range (± 3 ° C.) with respect to the set temperature immediately after the start of the hot water will be described. . The CPU 51 detects the temperature of hot water present in the heat exchanger 13 portion of the hot water supply pipe 21 based on temperature information from the heat exchanger thermistor 28. When the hot water temperature in the hot water supply pipe 21 detected by the heat exchanger thermistor 28 falls below the lower limit of the target temperature range in a state where no hot water is discharged, that is, in a state where there is no water flow, the CPU 51 starts the burner 12 from 1 second. It is ignited for a short time of 2 seconds, and operates to maintain the hot water temperature in the hot water supply pipe 21 within the target temperature range.
[0030]
In addition, such a heat retaining operation may be performed for a predetermined time after the last hot water discharge is stopped, and may be prepared for the next hot water discharge, or may be always performed during the operation of the water heater. .
[0031]
Next, the automatic hot water filling operation to the bathtub 40 will be described. FIG. 3 shows a flow of operation when filling the bathtub. When a bath automatic operation switch provided in the main body operation unit 55 or a remote control operation unit (not shown) is turned on (step S101; Y), first, an operation for confirming the amount of remaining water present in the bathtub 40 is performed (step S102). . Details of the remaining water confirmation operation will be described later.
[0032]
When the remaining water amount in the bathtub determined by the remaining water amount confirmation is less than the preset hot water amount at the completion of filling (step S103; N), the difference is obtained as the amount of hot water to be poured into the bathtub 40, and An amount of hot water is poured into the bathtub 40 (step S104). After the pouring, or when there is a necessary amount of hot water from the beginning (step S103; Y), it is checked whether or not the hot water temperature in the bathtub has reached the set boiling temperature (step S105).
[0033]
When the temperature of the hot water in the bathtub 40 is lower than the set temperature (step S105; N), reheating is performed (step S104), and when the set temperature is reached (step S105; Y), a notification sound or the like is sounded automatically. The hot water filling operation is finished (END).
[0034]
Next, the remaining water amount confirmation operation will be described. The amount of remaining water is confirmed by the following equation based on the temperature difference measured before and after reheating for a fixed time and the amount of heat added by reheating.
[0035]
[Expression 1]

[0036]
Here, V is the amount of water remaining in the bathtub (liter), Is is the input (Kcal / hr), t is the combustion time (hr), η is the thermal efficiency (%), and c is the specific heat of water (Kcal / Kg ° C). , T1 indicates the water temperature before reheating, and T2 indicates the water temperature after reheating.
[0037]
In order to obtain the remaining water amount with a small error based on the equation (1), it is desirable that the temperature detected by the bath temperature thermistor 34 indicates the average hot water temperature in the bathtub. In addition, it is necessary to grasp the amount of heat applied to the hot water in the bathtub as accurately as possible between the initial temperature detection and the subsequent temperature detection.
[0038]
By the way, since the inside of the bathtub usually has a better heat-retention state than the inside of the recirculation pipe 31, the water temperature in the bathtub 40 and the water temperature in the recirculation pipe 31 do not coincide with each other at the time of starting the automatic hot water filling. There are many cases. Therefore, before performing the temperature measurement for confirming the amount of remaining water, the circulation pump 32 is driven for a certain period of time to stir the remaining water in the bathtub 40 through the circulation pipe 31 and the bath temperature thermistor 34 attached to the circulation pipe 31 for reheating. The average hot water temperature in the bathtub 40 can be measured.
[0039]
Further, when the burner 12 is burned based on the Q function while the circulation pump 32 is being driven and the water in the bathtub is being stirred, an unexpected amount of heat is added to the water in the bathtub. (1) An error in the amount of residual water obtained by the calculation of the equation will increase. Further, since the water temperature at the time of checking the remaining water is often relatively low, if the circulation pump 32 circulates before the temperature detection, the heat on the hot water supply pipe 21 side is taken away by the water flowing through the recirculation circulation pipe 31. The hot water temperature in the hot water supply pipe 21 decreases. For this reason, while stirring the water in a bathtub with the circulation pump 32, possibility that the combustion for hot water temperature maintenance will be performed becomes very high. Therefore, the combustion of the burner 12 is forcibly prevented from the time when the water in the bathtub 40 is circulated by the circulation pump 32 until the temperature detection is finished.
[0040]
FIG. 4 shows the flow of the remaining water amount confirmation operation performed during automatic hot water filling. First, it sets so that the burner 12 may not ignite by the heat retention operation | movement by Q function (step S201). Actually, a prohibition flag for prohibiting combustion of the burner 12 based on the Q function is set at a predetermined address in the RAM 54.
[0041]
When the hot water temperature in the hot water supply pipe 21 falls below the lower limit of the target temperature range with no water flowing, the CPU 51 checks whether or not the prohibition flag is set, and when the prohibition flag is not set. Burns the burner 12 for a short time of 1-2 seconds. On the other hand, even if the hot water temperature in the hot water supply pipe 21 is below the lower limit of the target temperature range, if the prohibition flag is set, the burner 12 is controlled not to ignite.
[0042]
As described above, after the circulation pump 32 is driven for about 30 seconds in a state where combustion of the burner 12 based on the Q function is prohibited (step S202), the bath temperature thermistor 34 measures the water temperature (T1) in the bathtub 40 ( Step S203). Further, when the temperature detection is completed, a prohibition flag indicating that combustion of the burner 12 is prevented is reset (step S204).
[0043]
Next, the CPU 51 burns the burner 12 with a predetermined input and drives the circulation pump 32 to retreat the bath for a certain time (step S205). When reheating for a fixed time is completed, hot water remains in the recirculation circulation pipe 31 in this state, so that the prohibition flag is set again to prevent the burner 12 from burning based on the Q function. (Step S206), the circulation pump 32 is driven for about 30 seconds, and the water temperatures in the bathtub 40 and the recirculation circulation pipe 31 are averaged (Step S207).
[0044]
Thereafter, the temperature is detected to detect the water temperature (T2) in the bathtub after reheating (step S208), and the remaining water amount is obtained from the equation (1) (step S209).
[0045]
Thus, since the circulation pump 32 is operated and the water in the bathtub 40 and the recirculation pipe 31 is circulated and agitated in a state where combustion of the burner 12 based on the Q function is prohibited, a highly accurate temperature measurement and the amount of heat added. Therefore, the amount of residual water can be obtained with a small error according to the equation (1).
[0046]
When the faucet is opened during circulation for temperature detection and there is water flow, the burner 12 is ignited and burned in order to give priority to the hot water supply side. In this case, the circulation operation for checking the remaining water is performed again after the water flow is stopped.
[0047]
In addition, during the circulation operation for temperature detection, combustion of the burner 12 based on the Q function is not prevented, and when the burner 12 burns during the circulation operation, the circulation operation is performed in the same manner as when water has passed. It cannot be done again later. That is, since the heat in the hot water supply pipe 21 is taken away by the water flowing in the recirculation circulation pipe 31, the hot water temperature decreases immediately after the circulation operation is resumed after the combustion of the burner 12 based on the Q function is stopped. Combustion resumes, and the state where temperature cannot be detected continues indefinitely.
[0048]
In the embodiment described above, when checking the amount of remaining water, a predetermined amount of heat is added to the water in the bathtub by chasing, but water or hot water having a known temperature is introduced into the bathtub 40 via the pouring pipe 36. The amount of residual water can also be determined from the difference in water temperature before and after pouring and the temperature and amount of added water or hot water. Even in this case, it is necessary to circulate the water in the bathtub with the circulation pump 32 in order to accurately determine the average water temperature in the bathtub, and at that time, it is not possible to control the combustion of the burner 12 based on the Q function. This is similar to the case of heating by firing.
[0049]
Further, the embodiment has been described on the assumption that there is a certain amount of residual water in the bathtub. However, if the bath water switch 33 is not turned on even when the circulation pump 32 is turned, the inside of the bathtub 40 is “empty”. Alternatively, it may be determined that the water level is extremely low, water or hot water is poured in until the bath water switch 33 is turned on, and then the operation of checking the remaining water is performed again.
[0050]
Further, in the embodiment, the combustion of the burner 12 based on the Q function is prevented in both the circulation operation before the reheating and the circulation operation after the reheating. If the combustion based on this is prevented, the error of the residual water amount can be kept to a certain extent.
[0051]
That is, after the reheating, the water temperature in the bathtub is relatively high, so that the hot water circulating in the recirculation circulation pipe 31 is not easily deprived of the heat on the hot water supply pipe 21 side. Furthermore, since the hot water supply pipe 21 is also heated by the reheating operation, there is almost no possibility of falling below the target lower limit temperature during the circulation operation, and it is not necessary to intentionally prevent combustion by the Q function.
[0052]
【The invention's effect】
According to the one can two water channel type water heater according to the present invention, the combustion of the burner based on the operation of keeping the hot water in the hot water supply channel in advance in order to take out the hot water at almost the set temperature immediately after the start of the hot water, Since the water in the bathtub is circulated through the reheating channel in preparation for temperature measurement, the amount of heat applied by reheating the remaining water can be accurately grasped. It is possible to accurately measure the average temperature of the water in the inside and the follow-up channel, and to suppress an error in the remaining water amount obtained by calculation.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a one-can two-way water heater according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a circuit configuration of a control base included in the single can / two water channel type water heater according to the embodiment of the present invention.
FIG. 3 is a flowchart showing a flow of an operation performed by the one-can / two-channel water heater according to an embodiment of the present invention when automatic hot water filling is performed.
FIG. 4 is a flowchart showing a flow of a remaining water amount confirmation operation performed by the single can / two water channel type water heater according to an embodiment of the present invention when automatic hot water filling is performed.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Hot water heater 12 ... Burner 13 ... Heat exchanger 21 ... Hot water supply pipe 28 ... Heat exchange thermistor 31 ... Recirculation circulation pipe 32 ... Circulation pump 33 ... Bath flow water switch 34 ... Bath temperature thermistor 35 ... Pouring solenoid valve 36 ... pour pipe 40 ... tub

Claims

1 can 2 water channel type water heater that transfers heat from a burner to both water in a reheating channel through which water in a bathtub circulates and water in a hot water flow channel through which water is supplied, with one heat exchanger, In what has the function of filling the bathtub up to the set amount of hot water,
When the hot water is filled in the bathtub so as to reach the set amount of hot water, and a heat retention control unit for keeping the water in the hot water supply flow path within a predetermined temperature range by burning the burner in a state where it is not opened A residual water amount detection unit for detecting the amount of residual water in the bathtub, and a combustion prevention unit for preventing combustion of the burner based on an instruction of the heat retention control unit,
The residual water amount detecting unit, either or temperature water to reheating predetermined time with TOP UP known water or hot water in the bathtub, and pump the water in the bathtub through each of the reheating passages in its longitudinal by circulating thermometry the temperature, the difference in temperature of the reheating passage that temperature measuring before and after the reheating the reheating or the the heat or temperature and amount of the topped up with water or hot water was added via topped The amount of residual water in the bathtub is calculated based on
The combustion blocking portion, at least the residual water content detection unit within the bathtub through the reheating passages before or or temperature to reheating the water in the bathtub predetermined time performing to TOP UP known water or hot water while water is circulated by the pump is matched with the temperature of the water temperature and reheating passage in said bath and performing an operation for temperature taking the temperature of the burner based on the instruction of heat retaining control unit 1 can 2 water channel type water heater characterized by stopping combustion.

One can two water channel type water heater that transfers heat from a burner to both water in a reheating channel through which water in a bathtub circulates and water in a hot water flow channel through which water is supplied, with one heat exchanger, In what has the function of filling the bathtub up to the set amount of hot water,
A heat retention control unit configured to keep the water in the hot water supply channel within a predetermined temperature range by burning the burner in a state where the hot water at the set temperature is not opened so that the hot water is discharged within a predetermined time after opening; A remaining water amount detection unit that detects the amount of remaining water in the bathtub when filling the bathtub so as to obtain a hot water amount, and a combustion prevention unit that blocks combustion of the burner based on an instruction from the heat retention control unit. Have
The heat retention control unit is configured to burn the burner when the water temperature in the hot water flow path is below a predetermined lower limit temperature and maintain the water temperature in the hot water flow path in a predetermined temperature range,
The residual water amount detecting unit, the circulating water in the bath to or the temperature that reheating predetermined time with TOP UP known water or hot water, and pump the water in the bathtub through each of the reheating passages in its longitudinal The water temperature in the bathtub and the water temperature in the reheating channel are matched, and the water temperature is detected. The amount of heat applied by the reheating or the temperature and amount of the added water or hot water and the reheating Or based on the difference in the water temperature in the reheating channel measured before and after the addition, obtain the amount of residual water in the bathtub,
The combustion preventing unit detects the water temperature by causing the residual water amount detecting unit to circulate the water in the bathtub through the reheating channel with a pump so that the water temperature in the bathtub matches the water temperature in the reheating channel. A one-can / two-water heater, wherein the burner is controlled not to burn even when the temperature of the water in the hot water supply channel falls below the lower limit temperature while the operation is not being performed.

The combustion blocking portion, at least the residual water content detection unit within the bathtub through the reheating passages before or or temperature to reheating the water in the bathtub predetermined time performing to TOP UP known water or hot water the water is circulated by the pump is matched with the temperature of the water temperature and reheating passage in the bathtub and while temperature taking the water temperature, according to claim 2, wherein the blocking combustion of the burner 1 can 2 water channel type water heater.