JP5822787B2

JP5822787B2 - Circulating water heater

Info

Publication number: JP5822787B2
Application number: JP2012114740A
Authority: JP
Inventors: 正和安藤
Original assignee: Rinnai Corp
Current assignee: Rinnai Corp
Priority date: 2012-05-18
Filing date: 2012-05-18
Publication date: 2015-11-24
Anticipated expiration: 2032-05-18
Also published as: JP2013242066A

Description

本発明は、給湯停止時に給湯経路内の湯水を熱交換器を介して循環させることにより、給湯経路内の湯水を適温に維持する機能を有する循環型給湯装置に関する。 The present invention relates to a circulating hot water supply device having a function of maintaining hot water in a hot water supply path at an appropriate temperature by circulating hot water in the hot water supply path through a heat exchanger when hot water supply is stopped.

従来より、給水路に供給される水をバーナにより加熱される熱交換器により加熱して、給湯路に出湯する給湯装置において、給湯路の下流端付近と給水路を連通する連通路と、給水路及び給湯路と連通路とに形成される循環回路内の湯水を熱交換器を経由して循環させる循環ポンプとを備えた循環型給湯装置が知られている（例えば、特許文献１参照）。 Conventionally, in a hot water supply apparatus that heats water supplied to a water supply path by a heat exchanger heated by a burner and discharges the hot water into the hot water supply path, a communication path that connects the vicinity of the downstream end of the hot water supply path and the water supply path, There is known a circulation type hot water supply apparatus including a circulation pump that circulates hot water in a circulation circuit formed in a path, a hot water supply path, and a communication path via a heat exchanger (for example, see Patent Document 1). .

特許文献１に記載された循環型給湯装置においては、循環ポンプを常時作動させている。そして、給湯停止中もバーナを適宜燃焼させて熱交換器を流通する湯水を加熱することにより、循環回路内の湯水を適温に維持し、出湯栓が開栓されたときに直ちに適温の湯が出湯されるようにしている。 In the circulation type hot water supply apparatus described in Patent Document 1, the circulation pump is always operated. The hot water in the circulation circuit is maintained at an appropriate temperature by appropriately burning the burner while the hot water supply is stopped, so that the hot water in the circulation circuit is maintained at an appropriate temperature. I try to get hot water out.

ここで、水道水の硬度が高い地域では、熱交換器の吸熱管内で水に含まれるＣａＣＯ_３やＭｇＣＯ_３による、吸熱管内面への析出物（スケール）が付着し易くなる。そして、このように析出物が付着すると、熱交換器の熱交換効率が悪化して熱交換器の温度が上昇し、この温度上昇に起因して熱交換器の劣化が生じ得る。 Here, in an area where the hardness of tap water is high, precipitates (scale) due to CaCO ₃ or MgCO ₃ contained in the water in the heat absorption tube of the heat exchanger are likely to adhere to the inner surface of the heat absorption tube. When deposits adhere in this way, the heat exchange efficiency of the heat exchanger deteriorates and the temperature of the heat exchanger rises, and the heat exchanger can be deteriorated due to this temperature rise.

そこで、特許文献１に記載された循環型給湯装置においては、出湯栓が閉栓されていてバーナが燃焼中であるときに、流量調節弁を閉弁して循環回路内の湯水の循環を停止し（この停止によりバーナが消火する）、閉弁時点からの熱交換器の出口付近の湯水の温度の上昇幅が所定の閾値以上になったときに、析出物の付着により熱交換器が異常状態になっていると判別している。 Therefore, in the circulation type hot water supply apparatus described in Patent Document 1, when the tap is closed and the burner is burning, the flow rate control valve is closed to stop the circulation of the hot water in the circulation circuit. (The burner extinguishes due to this stop), and when the rise in the temperature of hot water near the outlet of the heat exchanger from the valve closing time exceeds a predetermined threshold, the heat exchanger is in an abnormal state due to deposits It is determined that

特開２００７−２６３４０３号公報JP 2007-263403 A

上記特許文献に記載された循環型給湯装置においては、循環ポンプを常時駆動している。そのため、流量調節弁により循環回路内の湯水の循環を停止したときにも、循環ポンプは作動を継続している。そして、この場合には、循環ポンプが空回りしてしまうため、循環ポンプの負荷が過大となって循環ポンプが過熱し、循環ポンプが劣化してしまうという不都合がある。 In the circulation type hot water supply apparatus described in the above patent document, the circulation pump is always driven. Therefore, even when the circulation of hot water in the circulation circuit is stopped by the flow rate control valve, the circulation pump continues to operate. In this case, since the circulation pump is idled, there is an inconvenience that the load on the circulation pump becomes excessive, the circulation pump is overheated, and the circulation pump is deteriorated.

本発明はかかる背景に鑑みてなされたものであり、循環ポンプの過熱を防止して、析出物の付着により熱交換器が異常状態になっていることを判別することができる循環型給湯装置を提供することを目的とする。 The present invention has been made in view of such a background, and provides a circulating hot water supply apparatus that can prevent overheating of a circulation pump and determine that a heat exchanger is in an abnormal state due to adhesion of precipitates. The purpose is to provide.

本発明は上記目的を達成するためになされたものであり、
バーナと、
給水路及び給湯路に接続されて前記バーナの燃焼排ガスにより加熱され、内部を流通する湯水を前記バーナの燃焼排ガスとの熱交換により加熱する熱交換器と、
出湯栓が接続された前記給湯路の下流端と前記給水路とを接続した連通路と、
前記給湯路と前記連通路との接続部から、前記連通路と前記給水路と前記熱交換器と前記給湯路とを経由して、該接続部に戻る循環回路内の湯水を循環させる循環ポンプと、
前記給湯路から前記出湯栓に供給される湯水の温度を検出する給湯温度センサと、
前記熱交換器の出口付近の湯水の温度を検出する熱交出口温度センサと、
前記出湯栓の開閉を検知する出湯栓開閉検知部と、
前記出湯栓が開栓状態であるときに、前記給湯温度センサの検出温度が所定の目標給湯温度となるように、前記バーナの燃焼量を制御する給湯運転を実行する給湯制御部と、
前記出湯栓が閉栓状態であるときに、前記循環ポンプを作動させて前記循環回路内の湯水を循環させると共に、前記給湯温度センサの検出温度が所定の適温範囲内となるように前記バーナの燃焼量を制御する適温維持運転を実行する適温維持制御部と、
前記適温維持運転が所定時間以上継続し、且つ、前記バーナが燃焼状態であるときに、前記適温維持制御部による前記適温維持運転の実行を禁止して、前記循環ポンプを停止すると共に前記バーナを消火し、該循環ポンプの停止後の前記熱交出口温度センサの検出温度の上昇度合が所定の第１異常判別レベル以上となったときに、前記熱交換器が異常状態であると判別する第１異常判別処理を実行する熱交異常判別部とを備える。 The present invention has been made to achieve the above object,
With a burner,
A heat exchanger connected to a water supply channel and a hot water supply channel, heated by the combustion exhaust gas of the burner, and heating hot water flowing through the interior by heat exchange with the combustion exhaust gas of the burner;
A communication path connecting the downstream end of the hot water supply path to which the hot water tap is connected and the water supply path;
A circulation pump that circulates hot water in a circulation circuit that returns to the connection portion from the connection portion between the hot water supply passage and the communication passage via the communication passage, the water supply passage, the heat exchanger, and the hot water supply passage. When,
A hot water supply temperature sensor for detecting the temperature of hot water supplied from the hot water supply passage to the tap;
A heat exchange outlet temperature sensor for detecting the temperature of hot water near the outlet of the heat exchanger;
A tap opening / closing detector for detecting opening / closing of the tap;
A hot water supply control unit for performing a hot water supply operation for controlling a combustion amount of the burner so that a detection temperature of the hot water supply temperature sensor becomes a predetermined target hot water supply temperature when the hot water tap is in an open state;
When the hot-water tap is closed, the circulation pump is operated to circulate hot water in the circulation circuit, and the burner burns so that the temperature detected by the hot water temperature sensor is within a predetermined appropriate temperature range. An optimal temperature maintenance control unit for executing an appropriate temperature maintenance operation for controlling the amount;
When the optimum temperature maintenance operation continues for a predetermined time or more and the burner is in a combustion state, the optimum temperature maintenance control unit prohibits execution of the optimum temperature maintenance operation, stops the circulation pump, and turns off the burner. First, the heat exchanger is determined to be in an abnormal state when extinguishing the fire and the degree of increase in the temperature detected by the heat exchange outlet temperature sensor after the circulation pump is stopped exceeds a predetermined first abnormality determination level. Ru and a heat交異normal discriminating unit that performs the first abnormality determination process.

本発明の上記構成によれば、前記熱交異常判別部は、前記第１異常判別処理を実行して前記熱交換器の異常状態を判別するときに、前記循環ポンプを停止することによって前記循環回路内の温水の流通を停止する。そのため、前記循環ポンプを作動状態に維持して開閉弁の閉弁により前記循環回路内の湯水の流通を停止する場合のように、過負荷により前記循環ポンプが劣化することを防止することができる。 According to the above configuration of the present invention, the heat exchange abnormality determining unit stops the circulation pump by stopping the circulation pump when executing the first abnormality determining process to determine the abnormal state of the heat exchanger. Stop circulating hot water in the circuit. Therefore, it is possible to prevent the circulation pump from deteriorating due to overload, as in the case where the circulation pump is maintained in an operating state and the circulation of hot water in the circulation circuit is stopped by closing the on-off valve. .

そして、上記構成において、
前記バーナは、前記バーナの燃焼範囲を区画すると共に燃焼と消火の個別切替えが可能な複数のバーナブロックを有し、
前記給湯制御部は、燃焼させる前記バーナブロックの選択を変更することによって前記バーナの燃焼量を制御し、
前記熱交異常判別部は、前記第１異常判別処理において、前記循環ポンプを停止する直前に燃焼状態であった前記バーナブロックの選択状態に応じて、前記第１異常判別レベルを変更することを特徴とする（第１発明）。 And in the above configuration ,
The burner has a plurality of burner blocks that partition the combustion range of the burner and can be individually switched between combustion and extinguishing,
The hot water supply control unit controls the amount of combustion of the burner by changing the selection of the burner block to be burned,
In the first abnormality determination process, the heat exchange abnormality determination unit changes the first abnormality determination level according to a selection state of the burner block that is in a combustion state immediately before stopping the circulation pump. Features ( first invention).

第１発明においては、燃焼させる前記バーナブロックの選択によって、前記熱交換器が前記バーナの燃焼排ガスにより加熱される範囲が相違する。そのため、前記熱交異常判別部が前記循環ポンプを停止して前記バーナを消火した後の前記熱交出口温度センサの検出温度の上昇度合は、前記循環ポンプを停止する直前に燃焼状態であった前記バーナブロックの選択状態に応じて変化する。 In the first invention, the range in which the heat exchanger is heated by the combustion exhaust gas of the burner differs depending on the selection of the burner block to be burned. Therefore, the degree of increase in the temperature detected by the heat exchange outlet temperature sensor after the heat exchange abnormality determining unit stops the circulation pump and extinguishes the burner was in a combustion state immediately before stopping the circulation pump. It changes according to the selection state of the burner block.

そのため、前記熱交異常判別部により、前記循環ポンプを停止する直前に燃焼状態であった前記バーナブロックの組合せに応じて前記第１異常判別レベルを変更することによって、前記熱交換器の異常判別をより精度良く行なうことができる。 Therefore, the heat exchanger abnormality determining unit changes the first abnormality determining level according to the combination of the burner blocks that were in a combustion state immediately before stopping the circulation pump, thereby determining the abnormality of the heat exchanger. Can be performed with higher accuracy.

また、上記構成において、
前記バーナは、前記バーナの燃焼範囲を区画すると共に燃焼と消火の個別切替えが可能な複数のバーナブロックを有し、
前記給湯制御部は、燃焼させる前記バーナブロックの選択を変更することによって前記バーナの燃焼量を制御し、
前記熱交異常判別部は、前記給湯運転が終了した時に、前記適温維持制御部による前記適温維持運転の実行を禁止して、前記循環ポンプを停止状態に維持すると共に前記バーナを消火状態に維持し、該給湯運転が終了した後の前記熱交出口温度センサの検出温度の上昇度合が、該給湯運転が終了する直前に燃焼状態であった前記バーナブロックの選択状態に応じて決定した第２異常判別レベル以上となったときに、前記熱交換器が異常状態であると判別する第２異常判別処理を実行することを特徴とする（第２発明）。 In the above configuration ,
The burner has a plurality of burner blocks that partition the combustion range of the burner and can be individually switched between combustion and extinguishing,
The hot water supply control unit controls the amount of combustion of the burner by changing the selection of the burner block to be burned,
When the hot water supply operation is completed, the heat exchange abnormality determining unit prohibits execution of the optimum temperature maintenance operation by the optimum temperature maintenance control unit, maintains the circulation pump in a stopped state, and maintains the burner in a fire extinguishing state. And the degree of increase in the temperature detected by the heat exchange outlet temperature sensor after the hot water supply operation is finished is determined according to the selected state of the burner block that was in the combustion state immediately before the hot water supply operation is finished. A second abnormality determination process is performed to determine that the heat exchanger is in an abnormal state when the abnormality determination level is exceeded ( second invention).

第２発明によれば、前記給湯運転が終了した時においても前記第２異常判別処理を実行して、前記熱交換器の異常状態を判別するが、前記給湯運転中に燃焼させる前記バーナブロックの選択によって、前記熱交換器が前記バーナの燃焼排ガスによって加熱される範囲が相違する。そのため、前記給湯運転が終了した後の前記熱交出口温度センサの検出温度の上昇度合は、前記給湯運転が終了する直前に燃焼状態であった前記バーナブロックの選択状態に応じて変化する。 According to the second invention, even when the hot water supply operation is finished, the second abnormality determination process is executed to determine the abnormal state of the heat exchanger, but the burner block to be burned during the hot water supply operation is determined. Depending on the selection, the range in which the heat exchanger is heated by the combustion exhaust gas of the burner is different. For this reason, the degree of increase in the temperature detected by the heat exchange outlet temperature sensor after the hot water supply operation is finished varies depending on the selection state of the burner block that was in the combustion state immediately before the hot water supply operation was finished.

そのため、前記第２異常判別処理における前記第２異常判別レベルを、前記給湯運転が終了する直前に燃焼状態であった前記バーナブロックの選択状態に応じて決定することによって、前記熱交換器が異常状態であることをより精度良く判別することができる。 Therefore, by determining the second abnormality determination level in the second abnormality determination process according to the selection state of the burner block that was in the combustion state immediately before the hot water supply operation is finished, the heat exchanger is abnormal. The state can be determined with higher accuracy.

また、上記構成において、
前記熱交異常判別部は、前記第１異常判別処理の実行中に、前記出湯栓が閉栓状態から開栓状態に切換わったときには、前記第１異常判別処理を中止して前記給湯制御部による前記給湯運転の実行を可能とすることを特徴とする（第３発明）。
さらに、第１発明又は第２発明において、前記熱交異常判別部は、前記第１異常判別処理の実行中に、前記出湯栓が閉栓状態から開栓状態に切換わったときには、前記第１異常判別処理を中止して前記給湯制御部による前記給湯運転の実行を可能とすることを特徴とする（第４発明）。 In the above configuration ,
When the hot water tap is switched from a closed state to an open state during execution of the first abnormality determination process, the heat exchange abnormality determination unit stops the first abnormality determination process and the hot water supply control unit The hot water supply operation can be performed ( third invention).
Furthermore, in the first invention or the second invention, when the hot-water tap is switched from a closed state to an opened state during execution of the first abnormality determination process, the heat exchange abnormality determination unit performs the first abnormality. The discrimination process is stopped, and the hot water supply operation can be performed by the hot water supply control unit (fourth invention).

第３発明及び第４発明によれば、前記第１異常判別処理の実行中に、使用者が前記出湯栓を開栓したときに、前記第１異常判別処理の継続により前記給湯運転の実行が妨げられて、前記出湯栓から湯が供給されない状態となることを防止することができる。 According to the third and fourth aspects of the invention , when the user opens the hot water tap during the execution of the first abnormality determination process, the hot water supply operation is executed by continuing the first abnormality determination process. It can be prevented that hot water is not supplied from the hot-water tap.

循環型給湯装置の構成図。The block diagram of a circulation type hot-water supply apparatus. 燃焼させるバーナブロックの選択によるバーナの燃焼量の変更範囲と、異常判別閾値の説明図。Explanatory drawing of the change range of the burner combustion amount by selection of the burner block to burn, and an abnormality determination threshold value. 第１異常判別処理のフローチャート。The flowchart of a 1st abnormality discrimination | determination process. 第２異常判別処理のフローチャート。The flowchart of the 2nd abnormality discrimination | determination process.

本発明の実施形態について、図１〜図４を参照して説明する。 An embodiment of the present invention will be described with reference to FIGS.

図１を参照して、本実施形態の循環型給湯装置１は、バーナ３とバーナ３の上方に配置された熱交換器４とを収容した缶体２、熱交換器４の入口（上流側の接続口）に接続された給水路５、熱交換器４の出口（下流側の接続口）に接続された給湯路６、バーナ３に燃料ガスを供給するガス供給路８、バーナ３に燃焼用空気を供給する燃焼ファン１４、給湯路６の出湯栓７が接続された下流端Ｘ１，Ｘ２と給水路５を連通する連通路４０、給湯路６と連通路４０との接続部から連通路４０と給水路５と熱交換器４と給湯路６を経由してこの接続部に至る循環回路５０内の湯水を循環させる循環ポンプ２５、循環型給湯装置１の全体的な作動を制御するコントローラ２３、及び、循環型給湯装置１を遠隔操作するためのリモコン２４を備えている。 Referring to FIG. 1, a circulation type hot water supply apparatus 1 of the present embodiment includes a can body 2 containing a burner 3 and a heat exchanger 4 disposed above the burner 3, an inlet (upstream side) of the heat exchanger 4. The gas supply path 8 for supplying fuel gas to the burner 3, the combustion in the burner 3 Combustion fan 14 for supplying the working air, downstream end X1, X2 to which hot water tap 7 of hot water supply path 6 is connected and communication path 40 that connects water supply path 5 and communication path from the connecting portion of hot water supply path 6 and communication path 40 A controller for controlling the overall operation of the circulating hot water supply apparatus 1 and the circulation pump 25 for circulating hot water in the circulation circuit 50 that reaches this connection portion via the 40, the water supply path 5, the heat exchanger 4 and the hot water supply path 6. 23 and a remote controller 24 for remotely operating the circulating hot water supply device 1.

熱交換器４は、多数の吸熱フィン４ａと吸熱フィン４ａを貫通した吸熱管４ｂとを有している。そして、上水道（図示しない）から給水路５に供給される水が熱交換器４においてバーナ３の燃焼排ガスとの熱交換により加熱されて給湯路６に送出され、出湯栓７から出湯される。 The heat exchanger 4 has a large number of endothermic fins 4a and an endothermic tube 4b penetrating the endothermic fins 4a. Then, the water supplied from the water supply (not shown) to the water supply channel 5 is heated by heat exchange with the combustion exhaust gas of the burner 3 in the heat exchanger 4, sent to the hot water supply channel 6, and discharged from the hot water tap 7.

バーナ３は、１０本の単位バーナ３０を有する大バーナブロック３ａと、５本の単位バーナ３０を有する小バーナブロック３ｂとにより燃焼範囲が区画され、各バーナブロック３ａ，３ｂの燃焼と消火を個別切替えが可能に構成されている。具体的には、大能力（大バーナブロック３ａ：燃焼、小バーナブロック３ｂ：燃焼）、中能力（大バーナブロック３ａ：燃焼、小バーナブロック３ｂ：消火）、小能力（大バーナブロック３ａ：消火、小バーナブロック３ｂ：燃焼）、という３段階にバーナ３の燃焼範囲が切替えられる。 The burner 3 has a combustion range defined by a large burner block 3a having ten unit burners 30 and a small burner block 3b having five unit burners 30, and individually burns and extinguishes each of the burner blocks 3a and 3b. Switching is possible. Specifically, large capacity (large burner block 3a: combustion, small burner block 3b: combustion), medium capacity (large burner block 3a: combustion, small burner block 3b: fire extinguishing), small capacity (large burner block 3a: fire extinguishing) , Small burner block 3b: combustion), the combustion range of the burner 3 is switched.

ガス供給路８には、上流側からガス元弁９とガス比例弁１０が設けられている。また、ガス供給路８から分岐した大バーナ分岐路３１には大バーナ切替弁３２が設けられ、ガス供給路８から分岐した小バーナ分岐路３３には小バーナ切替弁３４が設けられている。バーナ３の燃焼量は、大バーナ切替弁３２及び小バーナ切替弁３４の開閉切替えとガス比例弁１０の開度調節により制御される。 The gas supply path 8 is provided with a gas main valve 9 and a gas proportional valve 10 from the upstream side. A large burner switching valve 32 is provided in the large burner branch path 31 branched from the gas supply path 8, and a small burner switching valve 34 is provided in the small burner branch path 33 branched from the gas supply path 8. The amount of combustion of the burner 3 is controlled by opening / closing switching of the large burner switching valve 32 and small burner switching valve 34 and adjusting the opening of the gas proportional valve 10.

バーナ３の燃焼排ガスは、熱交換器４での熱交換が行われた後に、缶体２の上端部から排気筒１２を経由して屋外に排出される。排気筒１２は給気筒１３で囲われており、給気筒１３は、燃焼ファン１４の吸気口に連通した吸込みダクト１５に接続されている。燃焼ファン１４の作動により、外気が、給気筒１３と吸込みダクト１５と燃焼ファン１４とを介して缶体２内に燃焼用空気として供給される。 The combustion exhaust gas of the burner 3 is discharged from the upper end of the can 2 to the outside via the exhaust pipe 12 after heat exchange in the heat exchanger 4. The exhaust cylinder 12 is surrounded by a supply cylinder 13, and the supply cylinder 13 is connected to a suction duct 15 that communicates with an intake port of a combustion fan 14. By the operation of the combustion fan 14, outside air is supplied as combustion air into the can body 2 through the supply cylinder 13, the suction duct 15, and the combustion fan 14.

給水路５と給湯路６は、熱交換器４をバイパスするバイパス路１６により接続されている。給水路５のバイパス路１６との接続箇所の上流側には、給水路５を流通する湯水の流量を検出する流量センサ１７と、給水路５の開度を変更する流量調節弁１８とが設けられている。また、給水路５のバイパス路１６との接続箇所の下流側には、熱交換器４に供給される水の温度を検出する給水温度センサ１９が設けられている。 The water supply path 5 and the hot water supply path 6 are connected by a bypass path 16 that bypasses the heat exchanger 4. A flow rate sensor 17 for detecting the flow rate of hot water flowing through the water supply channel 5 and a flow rate adjusting valve 18 for changing the opening degree of the water supply channel 5 are provided on the upstream side of the connection point of the water supply channel 5 with the bypass channel 16. It has been. Further, a water supply temperature sensor 19 that detects the temperature of the water supplied to the heat exchanger 4 is provided on the downstream side of the connection portion of the water supply passage 5 with the bypass passage 16.

給湯路６のバイパス路１６との接続箇所の上流側には、熱交換器４の出口付近の湯水の温度を検出する熱交出口温度センサ２０が設けられている。また、給湯路６のバイパス路１６との接続箇所の下流側には、給湯路６から出湯栓７に供給される湯水の温度を検出する給湯温度センサ２１が設けられている。 A heat exchange outlet temperature sensor 20 that detects the temperature of hot water near the outlet of the heat exchanger 4 is provided on the upstream side of the location where the hot water supply path 6 is connected to the bypass path 16. A hot water supply temperature sensor 21 that detects the temperature of hot water supplied from the hot water supply passage 6 to the tap tap 7 is provided on the downstream side of the location where the hot water supply passage 6 is connected to the bypass passage 16.

バイパス路１６には、バイパス路１６の開度を変更して、熱交換器４側に流れる湯水の流量に対するバイパス路１６側に流れる湯水の流量の割合（バイパス比）を調節するためのバイパス流量調節弁２２が設けられている。 A bypass flow rate for adjusting the ratio (bypass ratio) of the flow rate of hot water flowing on the bypass channel 16 side to the flow rate of hot water flowing on the heat exchanger 4 side by changing the opening of the bypass channel 16 in the bypass channel 16. A control valve 22 is provided.

コントローラ２３は、図示しないＣＰＵ，メモリ等により構成された電子回路ユニットであり、コントローラ２３には、流量センサ１７、給水温度センサ１９、熱交出口温度センサ２０、及び、給湯温度センサ２１の各検出信号が入力される。また、コントローラ２３から出力される制御信号によって、ガス元弁９、ガス比例弁１０、大バーナ切替弁３２、小バーナ切替弁３４、燃焼ファン１４、流量調節弁１８、バイパス流量調節弁２２、及び、循環ポンプ２５の作動が制御される。さらに、コントローラ２３には、循環型給湯装置１を遠隔操作するためのリモコン２４が接続されている。 The controller 23 is an electronic circuit unit including a CPU, a memory, and the like (not shown). The controller 23 detects each of the flow rate sensor 17, the water supply temperature sensor 19, the heat exchange outlet temperature sensor 20, and the hot water supply temperature sensor 21. A signal is input. Further, according to the control signal output from the controller 23, the gas source valve 9, the gas proportional valve 10, the large burner switching valve 32, the small burner switching valve 34, the combustion fan 14, the flow rate adjusting valve 18, the bypass flow rate adjusting valve 22, and The operation of the circulation pump 25 is controlled. Furthermore, a remote controller 24 for remotely operating the circulating hot water supply device 1 is connected to the controller 23.

コントローラ２３は、メモリに保持された循環型給湯装置１の制御用プログラムをＣＰＵで実行することによって、給湯制御部６０、適温維持制御部６１、熱交異常判別部６２、及び、出湯栓開閉検知部６３として機能する。 The controller 23 executes a control program for the circulating hot water supply apparatus 1 held in the memory by the CPU, whereby a hot water supply control unit 60, an appropriate temperature maintenance control unit 61, a heat exchange abnormality determination unit 62, and a hot water tap opening / closing detection It functions as the unit 63.

給湯制御部６０は、出湯栓７が開栓状態となって上水道から給水路５への給水により、流量センサ１７の検出流量が最低動作流量以上になったときにバーナ３に点火し、給湯温度センサ２１の検出温度Ｔsがリモコン２４により設定された目標給湯温度と一致するように、燃焼ファン１４、ガス比例弁１０、大バーナ切替弁３２、及び、小バーナ切替弁３４の作動を制御して、バーナ３の燃焼量を調節すると共に、バイパス流量調節弁２２の開度を調節する給湯運転を実行する。 The hot water supply control unit 60 ignites the burner 3 when the tap tap 7 is in the open state and the detected flow rate of the flow rate sensor 17 exceeds the minimum operating flow rate due to the supply of water from the water supply to the water supply channel 5. The operations of the combustion fan 14, the gas proportional valve 10, the large burner switching valve 32, and the small burner switching valve 34 are controlled so that the detected temperature Ts of the sensor 21 matches the target hot water supply temperature set by the remote controller 24. Then, a hot water supply operation for adjusting the combustion amount of the burner 3 and adjusting the opening degree of the bypass flow rate adjusting valve 22 is executed.

また、バーナ３の燃焼量を最大にしても、給湯温度センサ２１の検出温度Ｔsが目標給湯温度に達しないときには、給湯制御部６０は、流量調節弁１８により給水路５の通水流量を減少させる。給湯制御部６０は、給湯運転の実行中は循環ポンプ２５を停止状態に維持し、これにより、循環ポンプ２５の消費電力を低減している。 Further, even if the combustion amount of the burner 3 is maximized, when the detected temperature Ts of the hot water supply temperature sensor 21 does not reach the target hot water supply temperature, the hot water supply control unit 60 decreases the water flow rate of the water supply passage 5 by the flow rate adjusting valve 18. Let The hot water supply control unit 60 keeps the circulation pump 25 in a stopped state during the hot water supply operation, thereby reducing the power consumption of the circulation pump 25.

適温維持制御部６１は、出湯栓７が閉栓状態であって上水道から給水路５への給水が停止しているときに、循環ポンプ２５を作動させて循環回路５０内の湯水を循環させると共に、バーナ３により熱交換器４を加熱する適温維持運転を実行する。 The appropriate temperature maintenance control unit 61 operates the circulation pump 25 to circulate hot water in the circulation circuit 50 when the tap tap 7 is closed and the water supply from the water supply to the water supply channel 5 is stopped. An appropriate temperature maintaining operation for heating the heat exchanger 4 by the burner 3 is executed.

適温維持運転において、適温維持制御部６１は、給湯温度センサ２１の検出温度が目標給湯温度Ｔcmに応じて設定された適温範囲内となるように、バーナ３を燃焼させて循環回路５０内を循環する湯水を加熱する。適温維持運転の実行により循環回路５０内の湯水の温度が目標給湯温度付近に維持されて、使用者が出湯栓７を開栓したときに出湯栓７から直ちに適温の湯が出湯されるため、出湯栓７の開栓時に冷えた水が流れ出て使用者に不快感を与えることを回避することができる。 In the optimum temperature maintenance operation, the optimum temperature maintenance control unit 61 circulates in the circulation circuit 50 by burning the burner 3 so that the temperature detected by the hot water supply temperature sensor 21 falls within the appropriate temperature range set according to the target hot water supply temperature Tcm. Heat the hot water. Since the temperature of the hot water in the circulation circuit 50 is maintained near the target hot water supply temperature by the execution of the appropriate temperature maintenance operation, the appropriate temperature hot water is immediately discharged from the hot water tap 7 when the user opens the hot water tap 7. It can be avoided that cold water flows out when the tap tap 7 is opened and the user is uncomfortable.

なお、適温維持運転における適温範囲を、リモコン２４により設定された目標給湯温度に応じて設定せずに、使用者が冷たさを感じない程度の固定値としてもよい。 In addition, it is good also as a fixed value of the grade which a user does not feel cold, without setting the suitable temperature range in a suitable temperature maintenance driving | operation according to the target hot-water supply temperature set with the remote control 24.

熱交異常判別部６２は、熱交換器４が吸熱管４ｂの内面に析出物が付着した異常状態になっていることを判別する。判別の処理の詳細については後述する。 The heat exchange abnormality determining unit 62 determines that the heat exchanger 4 is in an abnormal state in which precipitates are attached to the inner surface of the heat absorption tube 4b. Details of the determination process will be described later.

出湯栓開閉検知部６３は、出湯栓７の開閉状態を検知する。ここで、出湯栓７が閉栓状態であれば、適温維持制御部６１により適温維持運転が実行されて、循環回路５０内の湯水の温度が目標給湯温度Ｔcm付近に維持されるため、給水温度センサ１９の検出温度Ｔinは所定温度ＹＴin（目標給湯温度Ｔcmよりも若干低い温度に設定される）以上となる。そこで、出湯栓開閉検知部６３は、給水温度センサ１９の検出温度Ｔinが所定温度ＹＴin以上であるときに、出湯栓７が閉栓状態にあると検知する。 The hot-water tap open / close detector 63 detects the open / close state of the hot-water tap 7. Here, if the hot-water tap 7 is in the closed state, the optimum temperature maintenance control unit 61 executes the optimum temperature maintenance operation, and the temperature of the hot water in the circulation circuit 50 is maintained near the target hot water supply temperature Tcm. The detected temperature Tin of 19 is equal to or higher than a predetermined temperature YTin (set to a temperature slightly lower than the target hot water supply temperature Tcm). Therefore, the hot-water tap open / close detection unit 63 detects that the hot-water tap 7 is in the closed state when the detected temperature Tin of the feed water temperature sensor 19 is equal to or higher than the predetermined temperature YTin.

一方、出湯栓７が開栓状態であれば、上水道から給水路５に水が供給されるため、給水温度センサ１９の検出温度Ｔinは上水道からの水の温度となって、ＹＴinよりも低くなる。そのため、出湯栓開閉検知部６３は、給水温度センサ１９の検出温度ＴinがＹＴinよりも低いときに、出湯栓７が開栓状態であると検知する。 On the other hand, if the tap 7 is in the open state, water is supplied from the water supply to the water supply channel 5, so that the detected temperature Tin of the water supply temperature sensor 19 is the temperature of the water from the water supply and is lower than YTin. . Therefore, the hot-water tap open / close detection unit 63 detects that the hot-water tap 7 is in the open state when the detected temperature Tin of the feed water temperature sensor 19 is lower than YTin.

［第１異常判別処理］
次に、図２に示したフローチャートに従って、適温維持制御部６１による適温維持運転と、熱交異常判別部６２による熱交換器４の異常状態を判別するための第１異常判別処理の実行手順について説明する。 [First abnormality determination processing]
Next, according to the flowchart shown in FIG. 2, the execution procedure of the first temperature determination process for determining the optimum temperature maintenance operation by the optimum temperature maintenance control unit 61 and the abnormal state of the heat exchanger 4 by the heat exchange abnormality determination unit 62. explain.

ＳＴＥＰ１〜ＳＴＥＰ３及びＳＴＥＰ２０は、適温維持制御部６１による処理である。適温維持制御部６１は、ＳＴＥＰ１で出湯栓７からの出湯が停止しているか否かを判断する。適温維持制御部６１は、既に適温維持運転が開始されているときは、出湯栓開閉検知部６３により出湯栓７の閉栓が検知されているときに出湯が停止していると判断する。また、未だ適温維持運転が開始されていないときは、流量センサ１７の検出流量が所定の最低作動流量未満であるときに、出湯が停止していると判断する。 STEP 1 to STEP 3 and STEP 20 are processes by the appropriate temperature maintenance control unit 61. The appropriate temperature maintenance control unit 61 determines whether or not the hot water from the hot water tap 7 is stopped in STEP1. When the proper temperature maintenance operation has already been started, the appropriate temperature maintenance control unit 61 determines that the hot water supply is stopped when the hot water tap opening / closing detection unit 63 detects that the hot water tap 7 is closed. When the proper temperature maintenance operation has not yet been started, it is determined that the hot water has stopped when the detected flow rate of the flow rate sensor 17 is less than the predetermined minimum operating flow rate.

そして、出湯栓７からの出湯が停止しているときはＳＴＥＰ２に進み、リモコン２４により適温維持要求の設定がなされているか否かを判断する。一方、出湯栓７からの出湯が停止していないときにはＳＴＥＰ２０に分岐し、適温維持制御部６１は、適温維持運転を停止してＳＴＥＰ１に戻る。 When hot water from the hot water tap 7 is stopped, the process proceeds to STEP 2 and it is determined whether or not an appropriate temperature maintenance request is set by the remote controller 24. On the other hand, when the hot water from the hot water tap 7 is not stopped, the process branches to STEP 20, and the appropriate temperature maintenance control unit 61 stops the appropriate temperature maintenance operation and returns to STEP 1.

ＳＴＥＰ２で、適温維持制御部６１は、リモコン２４により適温維持要求の設定がなされているか否かを判断する。そして、適温維持要求の設定がなされているときにはＳＴＥＰ３に進んで、適温維持制御部６１は適温維持運転を実行する。適温維持運転において、適温維持制御部６１は、上述したように、循環ポンプ２５を作動させて循環回路５０内の湯水を循環させると共に、給湯温度センサ２１の検出温度Ｔsが適温範囲内とになるように、バーナ３の燃焼量を制御する。一方、適温維持要求の設定がなされていないときにはＳＴＥＰ２０に分岐する。 In STEP 2, the appropriate temperature maintenance control unit 61 determines whether an appropriate temperature maintenance request has been set by the remote controller 24. And when the setting of the appropriate temperature maintenance request | requirement is made, it progresses to STEP3 and the appropriate temperature maintenance control part 61 performs an appropriate temperature maintenance driving | operation. In the optimum temperature maintenance operation, the optimum temperature maintenance control unit 61 operates the circulation pump 25 to circulate hot water in the circulation circuit 50 as described above, and the detected temperature Ts of the hot water supply temperature sensor 21 falls within the appropriate temperature range. Thus, the combustion amount of the burner 3 is controlled. On the other hand, when the setting of the appropriate temperature maintenance request is not made, the process branches to STEP20.

続くＳＴＥＰ４〜ＳＴＥＰ１２及びＳＴＥＰ３０は、熱交異常判別部６２による処理である。熱交異常判別部６２は、ＳＴＥＰ４で、適温維持運転が１時間（本発明の所定時間に相当する）以上継続し、且つ、バーナ３が燃焼状態である、という条件が成立しているか否かを判断する。そして、この条件が成立しているときはＳＴＥＰ５に進み、この条件が成立していないときにはＳＴＥＰ１に戻る。 Subsequent STEP 4 to STEP 12 and STEP 30 are processes performed by the heat exchange abnormality determining unit 62. The heat exchange abnormality determining unit 62 determines whether or not the condition that the operation for maintaining the appropriate temperature is continued for one hour (corresponding to the predetermined time of the present invention) or more and the burner 3 is in the combustion state in STEP4. Judging. When this condition is satisfied, the process proceeds to STEP5, and when this condition is not satisfied, the process returns to STEP1.

ＳＴＥＰ５で、熱交異常判別部６２は、適温維持制御部６１による適温維持運転を禁止して、循環ポンプ２５の作動を停止すると共にバーナ３を消火する。続くＳＴＥＰ６で、熱交異常判別部６２は、リモコン２４の表示部（図示しない）に、熱交換器４の異常状態の判別を行っていることを示す「チェック表示」を行う。 In STEP 5, the heat exchange abnormality determination unit 62 prohibits the appropriate temperature maintenance operation by the appropriate temperature maintenance control unit 61, stops the operation of the circulation pump 25 and extinguishes the burner 3. In subsequent STEP 6, the heat exchange abnormality determining unit 62 performs “check display” on the display unit (not shown) of the remote controller 24 indicating that the abnormal state of the heat exchanger 4 is being determined.

次のＳＴＥＰ７で、熱交異常判別部６２は、ＳＴＥＰ５で循環ポンプ２５を停止する直前におけるバーナ３の能力段階（大能力、中能力、小能力）に応じた温度上昇閾値ＹΔＴout（本発明の第１異常判別レベルに相当する）を、メモリから読み出す。 In the next STEP 7, the heat exchange abnormality determining unit 62 determines the temperature increase threshold YΔTout (first capacity of the present invention) according to the capability stage (high capacity, medium capacity, small capacity) of the burner 3 immediately before stopping the circulation pump 25 in STEP 5. Is read from the memory).

ここで、図３（ａ）は、縦軸を燃焼ファン１４の回転速度に設定し、横軸をバーナ３の熱量に設定して、各能力段階でのバーナ３の熱量の変更範囲を、大能力をＬ、中能力をＭ、小能力をＳで示したものである。 Here, in FIG. 3A, the vertical axis is set to the rotational speed of the combustion fan 14, and the horizontal axis is set to the heat amount of the burner 3, so that the change range of the heat amount of the burner 3 at each capacity stage is large. The ability is indicated by L, the medium ability is indicated by M, and the small ability is indicated by S.

小能力Ｓは、ｓ1（最小熱量）〜ｓ3（最大熱量）の範囲をカバーし、中間熱量がｓ2である。図２（ａ）では、ｓ1〜ｓ2の範囲をＡで示し、ｓ2〜ｓ3の範囲をＢで示している。中能力Ｍは、ｍ1（最小熱量）〜ｍ3（最大熱量）の範囲をカバーし、中間熱量がｍ2である。図２（ａ）では、ｍ1〜ｍ2の範囲をＣで示し、ｍ2〜ｍ3の範囲をＤで示している。大能力Ｌは、ｌ1（最小熱量）〜ｌ3（最大熱量）の範囲をカバーし、中間熱量がｌ2である。図２（ａ）では、ｌ1〜ｌ2の範囲をＥで示し、ｌ2〜ｌ3の範囲をＦで示している。 The small capacity S covers the range of s1 (minimum heat amount) to s3 (maximum heat amount), and the intermediate heat amount is s2. In FIG. 2A, the range of s1 to s2 is indicated by A, and the range of s2 to s3 is indicated by B. The medium capacity M covers the range of m1 (minimum heat amount) to m3 (maximum heat amount), and the intermediate heat amount is m2. In FIG. 2A, the range of m1 to m2 is indicated by C, and the range of m2 to m3 is indicated by D. The large capacity L covers the range of l1 (minimum heat quantity) to l3 (maximum heat quantity), and the intermediate heat quantity is l2. In FIG. 2A, the range of l1 to l2 is indicated by E, and the range of l2 to l3 is indicated by F.

このように、バーナ３の能力を、燃焼させるバーナブロック（大バーナブロック３ａ，小バーナブロック３ｂ）の選択によって切替える場合、各能力毎にバーナ３の燃焼範囲が異なって、バーナ３の燃焼排ガスにより加熱される熱交換器４の範囲が変化する。そのため、バーナ３の燃焼を停止した後の熱交出口温度センサ２０の検出温度の上昇幅は、小能力→中能力→大能力と燃焼範囲が広くなるに従って大きくなる傾向があるが、この傾向は各能力毎に異なるため、一つの直線で表すことはできない。 Thus, when the capability of the burner 3 is switched by selecting the burner block to burn (large burner block 3a, small burner block 3b), the combustion range of the burner 3 differs for each capability, and the combustion exhaust gas of the burner 3 The range of the heat exchanger 4 to be heated changes. For this reason, the range of increase in the temperature detected by the heat exchange outlet temperature sensor 20 after the combustion of the burner 3 has stopped tends to increase as the combustion range increases, from small capacity → medium capacity → high capacity. Since each ability is different, it cannot be represented by a single straight line.

そこで、本実施形態では、図３（ｂ）に示したように、温度上昇閾値ＹΔＴoutを、各能力段階毎に設定する。すなわち、小能力のＡ（ｓ1〜ｓ2）の範囲（熱量小側）では７℃、Ｂ（ｓ2〜ｓ3）の範囲（熱量大側）では９℃に設定する。また、中能力のＣ（ｍ1〜ｍ2）の範囲（熱量小側）では１２℃、Ｄ（ｍ2〜ｍ3）の範囲（熱量大側）では１４℃に設定する。また、大能力のＥ（ｌ1〜ｌ2）の範囲（熱量小側）では１８℃、Ｆ（ｌ2〜ｌ3）の範囲（熱量大側）では２０℃に設定する。 Therefore, in the present embodiment, as shown in FIG. 3B, the temperature increase threshold YΔTout is set for each capability stage. That is, 7 ° C. is set in the range of A (s 1 to s 2) (small amount of heat) of small capacity, and 9 ° C. is set in the range of B (s 2 to s 3) (large amount of heat). Further, the temperature is set to 12 ° C. in the range of medium capacity C (m1 to m2) (small amount of heat) and 14 ° C. in the range of D (m2 to m3) (large amount of heat). Further, 18 ° C. is set in the range of high capacity E (l 1 to l 2) (small amount of heat), and 20 ° C. is set in the range of F (l 2 to l 3) (large amount of heat).

コントローラ２３のメモリには、図３（ｂ）の設定を以下の表１に示したようにマップ化したデータが、保持されている。 The memory of the controller 23 stores data obtained by mapping the settings shown in FIG. 3B as shown in Table 1 below.

熱交異常判別部６２は、ＳＴＥＰ５で循環ポンプ２５を停止する直前のバーナ３の能力段階（小能力／中能力／大能力）と各能力段階での熱量が属する範囲（小側／大側）を、表１のテーブルに適用して、使用する温度上昇閾値ＹΔＴoutを読み出す。 The heat exchanging abnormality determination unit 62 includes the capability stage (small capacity / medium capacity / large capacity) of the burner 3 immediately before stopping the circulation pump 25 in STEP 5 and the range to which the heat quantity at each capacity stage belongs (small side / large side). Is applied to the table of Table 1 to read out the temperature increase threshold YΔTout to be used.

そして、熱交異常判別部６２は、ＳＴＥＰ８でチェックタイマ（例えば、１〜２分にタイマ時間が設定される）をスタートさせ、続くＳＴＥＰ９〜ＳＴＥＰ１１のループにより、ＳＴＥＰ９で測定した熱交出口温度センサ２０の検出温度Ｔoutの上昇幅ΔＴoutが、ＳＴＥＰ１１でチェックタイマがタイムアップする前に、ＳＴＥＰ１０で温度上昇閾値ＹΔＴout以上となるか否かを判断する。 Then, the heat exchange abnormality determining unit 62 starts a check timer (for example, the timer time is set to 1 to 2 minutes) in STEP8, and the heat exchanger outlet temperature sensor measured in STEP9 by the subsequent loop of STEP9 to STEP11. Before the check timer expires in STEP 11, the increase width ΔTout of the detected temperature Tout of 20 is determined in STEP 10 to be equal to or higher than the temperature increase threshold YΔTout.

そして、ＳＴＥＰ１０で、熱交出口温度センサ２０の検出温度Ｔoutの上昇幅ΔＴoutが温度上昇閾値ＹΔＴout以上となったときは、熱交換器４の吸熱管４ｂの内側への析出物の付着により熱交換器４の熱交換効率が低下して、通水停止後の後沸きによる熱交出口温度センサ２０の検出温度Ｔoutの上昇幅ΔＴoutが大きくなったと判断することができる。 In STEP 10, when the increase width ΔTout of the detected temperature Tout of the heat exchange outlet temperature sensor 20 is equal to or greater than the temperature increase threshold YΔTout, heat exchange is caused by the deposits attached to the inside of the heat absorption pipe 4 b of the heat exchanger 4. It can be determined that the heat exchanging efficiency of the heat exchanger 4 has decreased, and the increase width ΔTout of the detected temperature Tout of the heat exchange outlet temperature sensor 20 due to post-boiling after the stop of water flow has increased.

そこで、この場合にはＳＴＥＰ３０に分岐し、熱交異常判別部６２は、リモコン２４の表示部に熱交換器４の異常を示す表示（例えば、エラーコードの表示等）を行って、熱交換器４が異常状態であることを報知する。 Therefore, in this case, the process branches to STEP 30, and the heat exchange abnormality determining unit 62 displays an indication of the abnormality of the heat exchanger 4 (for example, display of an error code) on the display unit of the remote controller 24, and the heat exchanger Informs that 4 is in an abnormal state.

一方、ＳＴＥＰ１１でチェックタイマがタイムアップしたときには、通水停止後の後沸きによる熱交出口温度センサ２０の検出温度Ｔoutの上昇幅ΔＴoutが小さく、熱交換器４の吸熱管４ｂの内側への析出物の付着が異常レベルにはないと判断することができる。 On the other hand, when the check timer expires in STEP 11, the increase width ΔTout of the detected temperature Tout of the heat exchange outlet temperature sensor 20 due to post-boiling after the stoppage of water flow is small, and the precipitation inside the heat absorption pipe 4 b of the heat exchanger 4 It can be determined that the adhesion of objects is not at an abnormal level.

そのため、この場合はＳＴＥＰ１２に進み、熱交異常判別部６２は、チェック表示を終了する。そしてＳＴＥＰ１３に進み、熱交異常判別部６２は、第１異常判別処理を終了する。 Therefore, in this case, the process proceeds to STEP 12, and the heat exchange abnormality determining unit 62 ends the check display. Then, the process proceeds to STEP 13 and the heat exchange abnormality determining unit 62 ends the first abnormality determining process.

［第２異常判別処理］
次に、図４に示したフローチャートに従って、熱交異常判別部６２による熱交換器４の異常状態を判別するための第２異常判別処理の実行手順について説明する。 [Second abnormality determination process]
Next, according to the flowchart shown in FIG. 4, the execution procedure of the 2nd abnormality determination process for determining the abnormal state of the heat exchanger 4 by the heat exchanger abnormality determination part 62 is demonstrated.

熱交異常判別部６２は、ＳＴＥＰ５０で給湯制御部６０により給湯運転が開始されるのを待ってＳＴＥＰ５１に進む。そして、ＳＴＥＰ５１で給湯制御部６０による給湯運転の実行が終了するのを待ってＳＴＥＰ５２に進む。 The heat exchange abnormality determining unit 62 waits for the hot water supply operation to be started by the hot water supply control unit 60 in STEP 50 and proceeds to STEP 51. Then, after waiting for the completion of the hot water supply operation by the hot water supply control unit 60 in STEP 51, the process proceeds to STEP 52.

ＳＴＥＰ５２で、熱交異常判別部６２は、適温維持制御部６１による適温維持運転を禁止して、循環ポンプ２５を停止状態に維持すると共にバーナ３を消火状態に維持する。続くＳＴＥＰ５３で、熱交異常判別部６２は、リモコン２４の表示部に、熱交換器４の異常状態の判別を行っていることを示す「チェック表示」を行う。 In STEP 52, the heat exchange abnormality determination unit 62 prohibits the appropriate temperature maintenance operation by the appropriate temperature maintenance control unit 61, maintains the circulation pump 25 in the stopped state, and maintains the burner 3 in the fire extinguishing state. In subsequent STEP 53, the heat exchange abnormality determining unit 62 performs “check display” on the display unit of the remote controller 24 indicating that the abnormal state of the heat exchanger 4 is being determined.

次にＳＴＥＰ５４で、熱交異常判別部６２は、ＳＴＥＰ５１で給湯運転が終了する直前のバーナ３の能力段階（小能力／中能力／大能力）と各能力段階での熱量が属する範囲（小側／大側）を、上記表１のテーブルに適用して、使用する温度上昇閾値ＹΔＴout（本発明の第２異常判別レベルに相当する）を読み出す。 Next, in STEP 54, the heat exchange abnormality determining unit 62 determines the range of the capacity level (small capacity / medium capacity / large capacity) of the burner 3 immediately before the hot water supply operation is completed in STEP 51 and the amount of heat in each capacity stage (small side). / Larger side) is applied to the table of Table 1 above, and the temperature increase threshold YΔTout (corresponding to the second abnormality determination level of the present invention) to be used is read.

なお、本実施形態では、第１熱交異常判別処理で使用する温度上昇閾値ＹΔＴoutと、第２熱交異常判別処理で使用する温度上昇閾値ＹΔＴoutを、上記表１のテーブルにより同じ条件により決定したが、異なる条件により設定するようにしてもよい。 In the present embodiment, the temperature increase threshold YΔTout used in the first heat exchange abnormality determination process and the temperature increase threshold YΔTout used in the second heat exchange abnormality determination process are determined under the same conditions using the table in Table 1 above. However, it may be set according to different conditions.

続くＳＴＥＰ５５で、熱交異常判別部６２は、チェックタイマ（例えば、１〜２分がタイマ時間に設定される）をスタートさせ、続くＳＴＥＰ５６〜ＳＴＥＰ５８のループにより、ＳＴＥＰ５６で測定した熱交出口温度センサ２０の検出温度Ｔoutの上昇幅ΔＴoutが、ＳＴＥＰ５８でチェックタイマがタイムアップする前に、ＳＴＥＰ５７で温度上昇閾値ＹΔＴout以上となるか否かを判断する。 In subsequent STEP55, the heat exchange abnormality determining unit 62 starts a check timer (for example, 1 to 2 minutes is set as the timer time), and the heat exchanger outlet temperature sensor measured in STEP56 by the loop of STEP56 to STEP58. Before the check timer expires in STEP 58, the increase width ΔTout of the detected temperature Tout of 20 is determined in STEP 57 as to whether or not the temperature increase threshold value YΔTout is exceeded.

そして、ＳＴＥＰ５７で、熱交出口温度センサ２０の検出温度Ｔoutの上昇幅ΔＴoutが温度上昇閾値ＹΔＴout以上となったときは、熱交換器４の吸熱管４ｂの内側への析出部の付着により熱交換器４の熱交換効率が低下して、通水停止後の後沸きによる熱交出口温度センサ２０の検出温度上昇幅ΔＴoutが大きくなったと判断することができる。 In STEP 57, when the increase width ΔTout of the detected temperature Tout of the heat exchange outlet temperature sensor 20 is equal to or greater than the temperature increase threshold YΔTout, heat exchange is caused by adhesion of a precipitation portion inside the heat absorption pipe 4b of the heat exchanger 4. It can be determined that the heat exchange efficiency of the vessel 4 has decreased and the detected temperature increase ΔTout of the heat exchange outlet temperature sensor 20 due to post-boiling after the stoppage of water flow has increased.

そこで、この場合にはＳＴＥＰ７０に分岐し、熱交異常判別部６２は、上述した図２のＳＴＥＰ３０と同様に、リモコン２４の表示部に熱交換器４の異常を示す表示を行って、熱交換器４が異常状態であることを報知する。 Therefore, in this case, the process branches to STEP 70, and the heat exchange abnormality determining unit 62 displays the abnormality of the heat exchanger 4 on the display unit of the remote controller 24 in the same manner as in STEP 30 of FIG. Notify that the device 4 is in an abnormal state.

一方、ＳＴＥＰ５８でチェックタイマがタイムアップしたときには、通水停止後の後沸きによる熱交出口温度センサ２０の検出温度Ｔoutの上昇幅ΔＴoutが小さく、熱交換器４の吸熱管４ｂの内側への析出物の付着が異常レベルにはないと判断することができる。 On the other hand, when the check timer expires in STEP 58, the increase width ΔTout of the detected temperature Tout of the heat exchange outlet temperature sensor 20 due to the post-boiling after the stoppage of water flow is small, and the precipitation inside the heat absorption pipe 4b of the heat exchanger 4 It can be determined that the adhesion of objects is not at an abnormal level.

そのため、この場合はＳＴＥＰ５９に進み、熱交異常判別部６２は、チェック表示を終了する。そして、ＳＴＥＰ６０に進み、熱交異常判別部６２は、第２異常判別処理を終了する。 Therefore, in this case, the process proceeds to STEP 59, and the heat exchange abnormality determining unit 62 ends the check display. Then, proceeding to STEP 60, the heat exchange abnormality determining unit 62 ends the second abnormality determining process.

なお、本実施形態では、熱交出口温度センサの検出温度の上昇度合として、検出温度の上昇幅を用いたが、検出温度の上昇割合を用いてもよい。 In this embodiment, as the degree of increase in the detected temperature of the heat exchange outlet temperature sensor, the range of increase in the detected temperature is used, but the rate of increase in the detected temperature may be used.

また、本実施形態において、熱交異常判別部６２は、第１異常判別処理と第２異常判別処理を実行して熱交換器４が異常状態であることを判別したが、少なくとも第１異常判別処理を実行して熱交換器４が異常状態であることを判別することにより、本発明の効果を得ることができる。 In the present embodiment, the heat exchange abnormality determining unit 62 executes the first abnormality determining process and the second abnormality determining process to determine that the heat exchanger 4 is in an abnormal state, but at least the first abnormality determining By executing the process and determining that the heat exchanger 4 is in an abnormal state, the effect of the present invention can be obtained.

また、本実施形態においては、熱交異常判別部６２は、複数のバーナブロック３ａ，３ｂからなるバーナ３を示して、バーナ３の能力段階に応じて温度上昇閾値ＹΔＴoutを変更したが、かかる変更を行わない場合であっても本発明の効果を得ることができる。 In the present embodiment, the heat exchange abnormality determining unit 62 shows the burner 3 including the plurality of burner blocks 3a and 3b and changes the temperature increase threshold YΔTout according to the capability stage of the burner 3. Even if it is not performed, the effect of the present invention can be obtained.

また、本実施形態においては、複数のバーナブロック３ａ、３ｂからなり、燃焼させるバーナブロックを選択することによって燃焼量を変更するバーナ３を示したが、バーナブロックの選択による燃焼量の変更を行わないバーナを用いてもよい。この場合に、燃焼停止直前のバーナの燃焼量に応じて、第１異常判定処理で用いる温度上昇閾値ＹΔＴoutを変更してもよい（例えば、燃焼停止直前のバーナの燃焼量が多いほど、温度上昇閾値ＹΔoutを高く設定する）。 Moreover, in this embodiment, although the burner 3 which consists of several burner blocks 3a and 3b and changes a combustion amount by selecting the burner block to burn was shown, the combustion amount is changed by selection of a burner block. No burner may be used. In this case, the temperature increase threshold YΔTout used in the first abnormality determination process may be changed according to the burner combustion amount immediately before the combustion stop (for example, the higher the burner combustion amount immediately before the combustion stop is, the higher the temperature rises). The threshold value YΔout is set high).

また、熱交異常判別部６２による第１異常判別処理が実行されているときに、出湯栓７が閉栓状態から開栓状態に切換わったときは、第１異常判別処理を中止して、給湯制御部６０による給湯運転の実行が可能となるようにしてもよい。 In addition, when the hot water tap 7 is switched from the closed state to the open state while the first abnormality determination process is being performed by the heat exchange abnormality determination unit 62, the first abnormality determination process is stopped and the hot water supply is stopped. You may enable it to perform the hot water supply operation by the control part 60. FIG.

１…循環型給湯装置、３…バーナ、３ａ…大バーナブロック、３ｂ…小バーナブロック、４…熱交換器、５…給水路、６…給湯路、１９…給水温度センサ、２０…熱交出口温度センサ、２１…給湯温度センサ、２３…コントローラ、２５…循環ポンプ、４０…連通路、５０…循環回路、６０…給湯制御部、６１…適温維持制御部、６２…熱交異常判別部、６３…出湯栓開閉検知部。 DESCRIPTION OF SYMBOLS 1 ... Circulation type hot water supply device, 3 ... Burner, 3a ... Large burner block, 3b ... Small burner block, 4 ... Heat exchanger, 5 ... Water supply path, 6 ... Hot water supply path, 19 ... Water supply temperature sensor, 20 ... Heat exchange outlet Temperature sensor, 21 ... Hot water supply temperature sensor, 23 ... Controller, 25 ... Circulation pump, 40 ... Communication path, 50 ... Circulation circuit, 60 ... Hot water supply control unit, 61 ... Optimal temperature maintenance control unit, 62 ... Heat exchange abnormality determination unit, 63 … Hot tap open / close detection part.

Claims

With a burner,
A heat exchanger connected to a water supply channel and a hot water supply channel, heated by the combustion exhaust gas of the burner, and heating hot water flowing through the interior by heat exchange with the combustion exhaust gas of the burner;
A communication path connecting the downstream end of the hot water supply path to which the hot water tap is connected and the water supply path;
A circulation pump that circulates hot water in a circulation circuit that returns to the connection portion from the connection portion between the hot water supply passage and the communication passage via the communication passage, the water supply passage, the heat exchanger, and the hot water supply passage. When,
A hot water supply temperature sensor for detecting the temperature of hot water supplied from the hot water supply passage to the tap;
A heat exchange outlet temperature sensor for detecting the temperature of hot water near the outlet of the heat exchanger;
A tap opening / closing detector for detecting opening / closing of the tap;
A hot water supply control unit for performing a hot water supply operation for controlling a combustion amount of the burner so that a detection temperature of the hot water supply temperature sensor becomes a predetermined target hot water supply temperature when the hot water tap is in an open state;
When the hot-water tap is closed, the circulation pump is operated to circulate hot water in the circulation circuit, and the burner burns so that the temperature detected by the hot water temperature sensor is within a predetermined appropriate temperature range. An optimal temperature maintenance control unit for executing an appropriate temperature maintenance operation for controlling the amount;
When the optimum temperature maintenance operation continues for a predetermined time or more and the burner is in a combustion state, the optimum temperature maintenance control unit prohibits execution of the optimum temperature maintenance operation, stops the circulation pump, and turns off the burner. First, the heat exchanger is determined to be in an abnormal state when extinguishing the fire and the degree of increase in the temperature detected by the heat exchange outlet temperature sensor after the circulation pump is stopped exceeds a predetermined first abnormality determination level. A heat exchanging abnormality discriminating unit that executes 1 anomaly discriminating process ;
The burner has a plurality of burner blocks that partition the combustion range of the burner and can be individually switched between combustion and extinguishing,
The hot water supply control unit controls the amount of combustion of the burner by changing the selection of the burner block to be burned,
In the first abnormality determination process, the heat exchange abnormality determination unit changes the first abnormality determination level according to a selection state of the burner block that is in a combustion state immediately before stopping the circulation pump. A circulating hot water supply device.

With a burner,
A heat exchanger connected to a water supply channel and a hot water supply channel, heated by the combustion exhaust gas of the burner, and heating hot water flowing through the interior by heat exchange with the combustion exhaust gas of the burner;
A communication path connecting the downstream end of the hot water supply path to which the hot water tap is connected and the water supply path;
A circulation pump that circulates hot water in a circulation circuit that returns to the connection portion from the connection portion between the hot water supply passage and the communication passage via the communication passage, the water supply passage, the heat exchanger, and the hot water supply passage. When,
A hot water supply temperature sensor for detecting the temperature of hot water supplied from the hot water supply passage to the tap;
A heat exchange outlet temperature sensor for detecting the temperature of hot water near the outlet of the heat exchanger;
A tap opening / closing detector for detecting opening / closing of the tap;
A hot water supply control unit for performing a hot water supply operation for controlling a combustion amount of the burner so that a detection temperature of the hot water supply temperature sensor becomes a predetermined target hot water supply temperature when the hot water tap is in an open state;
When the hot-water tap is closed, the circulation pump is operated to circulate hot water in the circulation circuit, and the burner burns so that the temperature detected by the hot water temperature sensor is within a predetermined appropriate temperature range. An optimal temperature maintenance control unit for executing an appropriate temperature maintenance operation for controlling the amount;
When the optimum temperature maintenance operation continues for a predetermined time or more and the burner is in a combustion state, the optimum temperature maintenance control unit prohibits execution of the optimum temperature maintenance operation, stops the circulation pump, and turns off the burner. First, the heat exchanger is determined to be in an abnormal state when extinguishing the fire and the degree of increase in the temperature detected by the heat exchange outlet temperature sensor after the circulation pump is stopped exceeds a predetermined first abnormality determination level. A heat exchanging abnormality discriminating unit that executes 1 anomaly discriminating process ;
The burner has a plurality of burner blocks that partition the combustion range of the burner and can be individually switched between combustion and extinguishing,
The hot water supply control unit controls the amount of combustion of the burner by changing the selection of the burner block to be burned,
When the hot water supply operation is completed, the heat exchange abnormality determining unit prohibits execution of the optimum temperature maintenance operation by the optimum temperature maintenance control unit, maintains the circulation pump in a stopped state, and maintains the burner in a fire extinguishing state. And the degree of increase in the temperature detected by the heat exchange outlet temperature sensor after the hot water supply operation is finished is determined according to the selected state of the burner block that was in the combustion state immediately before the hot water supply operation is finished. A circulation type hot water supply apparatus that executes a second abnormality determination process for determining that the heat exchanger is in an abnormal state when an abnormality determination level is reached .

With a burner,
A heat exchanger connected to a water supply channel and a hot water supply channel, heated by the combustion exhaust gas of the burner, and heating hot water flowing through the interior by heat exchange with the combustion exhaust gas of the burner;
A communication path connecting the downstream end of the hot water supply path to which the hot water tap is connected and the water supply path;
A circulation pump that circulates hot water in a circulation circuit that returns to the connection portion from the connection portion between the hot water supply passage and the communication passage via the communication passage, the water supply passage, the heat exchanger, and the hot water supply passage. When,
A hot water supply temperature sensor for detecting the temperature of hot water supplied from the hot water supply passage to the tap;
A heat exchange outlet temperature sensor for detecting the temperature of hot water near the outlet of the heat exchanger;
A tap opening / closing detector for detecting opening / closing of the tap;
A hot water supply control unit for performing a hot water supply operation for controlling a combustion amount of the burner so that a detection temperature of the hot water supply temperature sensor becomes a predetermined target hot water supply temperature when the hot water tap is in an open state;
When the hot-water tap is closed, the circulation pump is operated to circulate hot water in the circulation circuit, and the burner burns so that the temperature detected by the hot water temperature sensor is within a predetermined appropriate temperature range. An optimal temperature maintenance control unit for executing an appropriate temperature maintenance operation for controlling the amount;
When the optimum temperature maintenance operation continues for a predetermined time or more and the burner is in a combustion state, the optimum temperature maintenance control unit prohibits execution of the optimum temperature maintenance operation, stops the circulation pump, and turns off the burner. First, the heat exchanger is determined to be in an abnormal state when extinguishing the fire and the degree of increase in the temperature detected by the heat exchange outlet temperature sensor after the circulation pump is stopped exceeds a predetermined first abnormality determination level. A heat exchanging abnormality discriminating unit that executes 1 anomaly discriminating process ;
When the hot water tap is switched from a closed state to an open state during execution of the first abnormality determination process, the heat exchange abnormality determination unit stops the first abnormality determination process and the hot water supply control unit A circulating hot water supply apparatus capable of performing the hot water supply operation .

In the circulating hot water supply device according to claim 1 or 2 ,
When the hot water tap is switched from a closed state to an open state during execution of the first abnormality determination process, the heat exchange abnormality determination unit stops the first abnormality determination process and the hot water supply control unit A circulating hot water supply apparatus capable of performing the hot water supply operation.