JP2015001316A

JP2015001316A - Storage type water heater

Info

Publication number: JP2015001316A
Application number: JP2013124860A
Authority: JP
Inventors: 真行須藤; Masayuki Sudo; 柳本　圭; Kei Yanagimoto; 圭柳本; 利幸佐久間; Toshiyuki Sakuma; 洋介貞廣; Yosuke Sadahiro; 風間　史郎; Shiro Kazama; 史郎風間; 忠明柳; Tadaaki Yanagi
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2013-06-13
Filing date: 2013-06-13
Publication date: 2015-01-05

Abstract

PROBLEM TO BE SOLVED: To provide a storage type water heater capable of improving energy saving performance while keeping ease of use.SOLUTION: A storage type water heater 35 includes: mixing means (medium temperature water mixing valve 40, mixing valve 22 for hot water supply) for mixing hot water supplied from a hot water storage tank 8 and low-temperature water supplied from a water source, and supplying the resultant mixed hot water to a first hot water supply pipe 24; and control means 36 for performing switching between a fixed temperature hot water supply mode performing control so that a temperature of the hot water supplied to the first hot water supply pipe 24 is kept fixed and a variable temperature hot water supply mode performing control so that the temperature of the hot water supplied to the first hot water supply pipe 24 is periodically changed. The control means 36, when starting the supply of hot water to the second hot water supply pipe 25 from a state of supplying the hot water to the first hot water supply pipe 24 in the variable temperature hot water supply mode without supplying the hot water to the second hot water supply pipe 25, switches the variable temperature hot water supply mode to the fixed temperature hot water supply mode, or shortens the period of the periodical change of the variable temperature hot water supply mode in comparison with an original period, prior to the start of the hot water to the second hot water supply pipe 25.

Description

本発明は、貯湯式給湯機に関する。 The present invention relates to a hot water storage type water heater.

例えばヒートポンプなどの加熱手段により沸き上げられた湯を貯湯タンクに貯え、貯湯タンクから取り出した湯を用いて、浴槽、シャワー、台所および洗面所の蛇口などの給湯先に給湯する貯湯式給湯機が広く用いられている。 For example, there is a hot water storage water heater that stores hot water boiled by heating means such as a heat pump in a hot water storage tank, and uses the hot water taken out of the hot water storage tank to supply hot water to hot water sources such as bathtubs, showers, kitchens, and toilet faucets. Widely used.

特許文献１には、シャワーへの給湯流量を周期的に変動させることで、節水および省エネルギーを図るようにした給湯機が開示されている。 Patent Document 1 discloses a water heater that saves water and saves energy by periodically changing the flow rate of hot water to the shower.

特開２０１１−２５２６８４号公報JP 2011-252684 A

特許文献１に開示された技術のように、シャワーへの給湯流量を変動させ、周期的に流量を低下させることで、ある程度の節水効果および省エネルギー効果が生じる場合もある。しかしながら、シャワーの流量が周期的に低下することで、すすぎ性能が低下し、使いにくくなる可能性がある。また、必要なすすぎ時間が長くなり、十分な節水効果および省エネルギー効果が得られないことも考えられる。 As in the technique disclosed in Patent Document 1, a certain amount of water saving effect and energy saving effect may occur by changing the hot water supply flow rate to the shower and periodically reducing the flow rate. However, when the flow rate of the shower is periodically decreased, the rinsing performance may be decreased and it may be difficult to use. In addition, the necessary rinsing time becomes long, and it is considered that sufficient water saving effect and energy saving effect cannot be obtained.

本発明は、上述のような課題を解決するためになされたもので、使いやすさを維持しながら、省エネルギー性を向上することのできる貯湯式給湯機を提供することを目的とする。 The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a hot water storage type hot water heater capable of improving energy saving while maintaining ease of use.

本発明に係る貯湯式給湯機は、温水を貯える貯湯タンクと、貯湯タンクから供給される温水と、水源から供給される低温水とを混合して、第１給湯配管へ供給する混合手段と、貯湯タンクから供給される温水を需要側へ送る第２給湯配管と、第１給湯配管へ供給される温水の温度が一定になるように混合手段を制御する定温給湯モードと、第１給湯配管へ供給される温水の温度が周期的に変動するように混合手段を制御する変温給湯モードとを切り替える制御手段と、を備え、制御手段は、第２給湯配管へ温水を供給せずに変温給湯モードにて第１給湯配管へ温水を供給している状態から、第２給湯配管への温水の供給を開始する場合には、その開始に先立って、変温給湯モードから定温給湯モードへ切り替えるか、または、変温給湯モードの周期的な変動の周期を元の周期より短くするものである。 The hot water storage type hot water heater according to the present invention is a hot water storage tank for storing hot water, hot water supplied from the hot water storage tank, and low temperature water supplied from a water source, and mixing means for supplying to the first hot water supply pipe, A second hot water supply pipe for sending hot water supplied from the hot water storage tank to the demand side, a constant temperature hot water supply mode for controlling the mixing means so that the temperature of the hot water supplied to the first hot water supply pipe becomes constant, and the first hot water supply pipe Control means for switching to a variable temperature hot water supply mode for controlling the mixing means so that the temperature of the supplied hot water fluctuates periodically, and the control means changes the temperature without supplying hot water to the second hot water supply pipe. When the hot water supply to the second hot water supply pipe is started from the state where the hot water is supplied to the first hot water supply pipe in the hot water supply mode, the variable temperature hot water supply mode is switched to the constant temperature hot water supply mode prior to the start. Or variable temperature hot water supply mode It is to be shorter than the original cycle period of the periodic variation.

本発明によれば、使いやすさを維持しながら、省エネルギー性を向上することが可能となる。 According to the present invention, energy saving can be improved while maintaining ease of use.

本発明の実施の形態１の貯湯式給湯機を示す構成図である。It is a block diagram which shows the hot water storage type water heater of Embodiment 1 of this invention.

以下、図面を参照して本発明の実施の形態について説明する。
実施の形態１．
図１は、本発明の実施の形態１の貯湯式給湯機の構成図である。図１に示すように、本実施の形態１の貯湯式給湯機３５は、タンクユニット３３と、ヒートポンプサイクルを利用するＨＰ（ヒートポンプ）ユニット７と、運転動作指令や設定値の変更操作をするユーザーインターフェース装置としてのリモコン装置４４とを備えている。ＨＰユニット７とタンクユニット３３とは、ＨＰ往き配管１４、ＨＰ戻り配管１５、および電気配線（図示省略）とを介して、接続されている。 Embodiments of the present invention will be described below with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a hot water storage type hot water supply apparatus according to Embodiment 1 of the present invention. As shown in FIG. 1, a hot water storage type water heater 35 according to the first embodiment includes a tank unit 33, an HP (heat pump) unit 7 that uses a heat pump cycle, and a user who performs an operation to change an operation command or a set value. And a remote control device 44 as an interface device. The HP unit 7 and the tank unit 33 are connected to each other via an HP outgoing pipe 14, an HP return pipe 15, and electrical wiring (not shown).

タンクユニット３３には、制御手段３６が内蔵されている。タンクユニット３３およびＨＰユニット７が備える各種の弁類、ポンプ類等の作動は、これらと電気的に接続された制御手段３６により制御される。制御手段３６とリモコン装置４４とは、相互に通信可能に接続されている。リモコン装置４４には、図示を省略するが、貯湯式給湯機３５の状態等の情報を表示する表示部、使用者が操作するスイッチ等の操作部、スピーカ、マイク等が搭載されている。 The tank unit 33 includes a control means 36. The operations of various valves, pumps and the like provided in the tank unit 33 and the HP unit 7 are controlled by a control means 36 electrically connected thereto. The control means 36 and the remote control device 44 are connected so that they can communicate with each other. Although not shown in the drawings, the remote control device 44 includes a display unit that displays information such as the state of the hot water storage water heater 35, an operation unit such as a switch operated by a user, a speaker, a microphone, and the like.

ＨＰユニット７は、タンクユニット３３が備える貯湯タンク８から導かれた低温水を加熱するための加熱手段として機能する。ＨＰユニット７は、圧縮機１、水冷媒熱交換器３、膨張弁４、空気熱交換器６を冷媒配管５にて環状に接続し、ヒートポンプサイクルを構成している。水冷媒熱交換器３は、冷媒配管５を流れる冷媒とタンクユニット３３から導かれた低温水との間で熱交換を行うためのものである。 The HP unit 7 functions as a heating means for heating the low-temperature water led from the hot water storage tank 8 provided in the tank unit 33. The HP unit 7 connects the compressor 1, the water refrigerant heat exchanger 3, the expansion valve 4, and the air heat exchanger 6 in a ring shape with a refrigerant pipe 5 to constitute a heat pump cycle. The water-refrigerant heat exchanger 3 is for exchanging heat between the refrigerant flowing through the refrigerant pipe 5 and the low-temperature water led from the tank unit 33.

タンクユニット３３には、以下の各種部品や配管などが内蔵されている。貯湯タンク８は、温水を貯えるものである。貯湯タンク８の下部に設けられた水導入口８ａには、第３給水配管９ｃが接続されている。水道等の水源から供給される低温水は、減圧弁３１で所定圧力に調圧された上で、第３給水配管９ｃを通って貯湯タンク８内に流入する。貯湯タンク８の上部に設けられた温水導入出口８ｄには、貯湯タンク８内に貯留された高温水を取り出すための給湯配管２１ａと、送湯配管１３とが接続されている。貯湯タンク８には、ＨＰユニット７を用いて加熱された高温水が温水導入出口８ｄから流入するとともに、第３給水配管９ｃからの低温水が水導入口８ａから流入する。貯湯タンク８内には、上側が高温、下側が低温となる温度成層を形成して、温水が貯留される。また、貯湯タンク８の表面には、複数の貯湯温度センサ４１，４２，４３が高さを変えて取り付けられている。これら貯湯温度センサ４１，４２，４３で貯湯タンク８内の温水の温度分布を検出することにより、貯湯タンク８内の残湯量あるいは蓄熱量が把握され、ＨＰユニット７による貯湯タンク８内の温水の沸き上げ運転の開始および停止などが制御される。 The tank unit 33 incorporates the following various parts and piping. The hot water storage tank 8 stores hot water. A third water supply pipe 9 c is connected to a water inlet 8 a provided at the lower part of the hot water storage tank 8. Low-temperature water supplied from a water source such as water supply is adjusted to a predetermined pressure by the pressure reducing valve 31 and then flows into the hot water storage tank 8 through the third water supply pipe 9c. A hot water supply pipe 21 a for taking out high-temperature water stored in the hot water storage tank 8 and a hot water supply pipe 13 are connected to the hot water introduction outlet 8 d provided in the upper part of the hot water storage tank 8. Hot water heated using the HP unit 7 flows into the hot water storage tank 8 from the hot water introduction outlet 8d, and low temperature water from the third water supply pipe 9c flows from the water introduction port 8a. In the hot water storage tank 8, hot water is stored by forming a temperature stratification in which the upper side is hot and the lower side is low. A plurality of hot water storage temperature sensors 41, 42, and 43 are attached to the surface of the hot water storage tank 8 at different heights. By detecting the temperature distribution of the hot water in the hot water storage tank 8 with these hot water storage temperature sensors 41, 42, 43, the remaining hot water amount or the heat storage amount in the hot water storage tank 8 is grasped, and the hot water in the hot water storage tank 8 by the HP unit 7 is obtained. The start and stop of the boiling operation are controlled.

タンクユニット３３内には、熱源ポンプ１２および利用側熱交換器２０が内蔵されている。熱源ポンプ１２は、タンクユニット３３内の後述する各種配管に温水を循環させるためのポンプであり、ＨＰ往き配管１４上に設けられている。利用側熱交換器２０は、貯湯タンク８あるいはＨＰユニット７から供給される高温水を利用して、２次側の加熱対象水（浴槽水や暖房用水など）を加熱するための熱交換器である。本実施の形態では、利用側熱交換器２０の２次側の構成として、浴槽３０から導出した浴槽水を循環させるふろ往き配管２７およびふろ戻り配管２８を例示し説明する。利用側熱交換器２０は、ふろ往き配管２７と、ふろ戻り配管２８と、浴槽３０とで形成される循環経路の途中に設置されている。また、ふろ戻り配管２８の途中には、浴槽水を循環させるためのふろ循環ポンプ２９と、浴槽３０から出た浴槽水の温度を検出するためのふろ戻り温度センサ３８とが設置されている。ふろ往き配管２７の途中には、利用側熱交換器２０から出た熱交換後の湯の温度を検出するためのふろ往き温度センサ３７が設置されている。 In the tank unit 33, the heat source pump 12 and the use side heat exchanger 20 are built. The heat source pump 12 is a pump for circulating hot water through various pipes to be described later in the tank unit 33, and is provided on the HP outgoing pipe 14. The use-side heat exchanger 20 is a heat exchanger for heating secondary water to be heated (tub water, heating water, etc.) using high-temperature water supplied from the hot water storage tank 8 or the HP unit 7. is there. In the present embodiment, as the secondary side configuration of the use-side heat exchanger 20, a bath piping 27 and a bath return piping 28 for circulating the bath water led out from the bath 30 will be exemplified and described. The use side heat exchanger 20 is installed in the middle of a circulation path formed by the forward piping 27, the return piping 28, and the bathtub 30. Further, a bath circulation pump 29 for circulating bath water and a bath return temperature sensor 38 for detecting the temperature of bath water discharged from the bath 30 are installed in the middle of the bath return pipe 28. In the middle of the bath piping 27, a bath temperature sensor 37 for detecting the temperature of the hot water after the heat exchange from the use side heat exchanger 20 is installed.

三方弁１１は、流入口であるａポートおよびｂポートと、流出口であるｃポートとを有する流路切替手段である。四方弁１８は、流入口であるｂポートおよびｃポートと、流出口であるａポートおよびｄポートとを有する流路切替手段である。四方弁１８は、４つの経路、ａ−ｂ、ａ−ｃ、ｂ−ｄ、ｃ−ｄの間で流路切替可能に構成されている。また、タンクユニット３３は、水導出口配管１０、温水導入配管２０ａ、第１バイパス配管１６、温水導出配管２０ｂ、および第２バイパス配管１７を有している。水導出口配管１０は、貯湯タンク８の下部に設けられた水導出口８ｂと三方弁１１のａポートとを接続する。ＨＰ往き配管１４は、三方弁１１のｃポートとＨＰユニット７の入口側とを接続する。ＨＰ戻り配管１５は、ＨＰユニット７の出口側と四方弁１８のｃポートとを接続する。送湯配管１３は、四方弁１８のｄポートと、貯湯タンク８上部の温水導入出口８ｄとを接続する。第１バイパス配管１６は、四方弁１８のａポートと、貯湯タンク８の中央部から下部の間に設けられた温水導入口８ｃとを接続する。温水導入配管２０ａは、送湯配管１３の途中から分岐し、利用側熱交換器２０の１次側入口に接続される。温水導出配管２０ｂは、利用側熱交換器２０の１次側出口と三方弁１１のｂポートとを接続する。第２バイパス配管１７は、ＨＰ往き配管１４における熱源ポンプ１２とＨＰユニット７の入口側との間から分岐し、四方弁１８のｂポートに接続される。 The three-way valve 11 is a flow path switching means having an a port and a b port as inflow ports and a c port as an outflow port. The four-way valve 18 is a flow path switching means having b and c ports that are inflow ports and a and d ports that are outflow ports. The four-way valve 18 is configured to be able to switch the flow path among four paths, ab, ac, bd, and cd. The tank unit 33 includes a water outlet port pipe 10, a hot water introduction pipe 20 a, a first bypass pipe 16, a hot water outlet pipe 20 b, and a second bypass pipe 17. The water outlet port pipe 10 connects a water outlet 8 b provided at the lower part of the hot water storage tank 8 and the a port of the three-way valve 11. The HP forward piping 14 connects the c port of the three-way valve 11 and the inlet side of the HP unit 7. The HP return pipe 15 connects the outlet side of the HP unit 7 and the c port of the four-way valve 18. The hot water supply pipe 13 connects the d port of the four-way valve 18 and the hot water introduction outlet 8 d above the hot water storage tank 8. The first bypass pipe 16 connects the a port of the four-way valve 18 and a hot water inlet 8 c provided between the central part and the lower part of the hot water storage tank 8. The hot water introduction pipe 20 a branches off from the middle of the hot water supply pipe 13 and is connected to the primary side inlet of the use side heat exchanger 20. The hot water outlet pipe 20 b connects the primary side outlet of the use side heat exchanger 20 and the b port of the three-way valve 11. The second bypass pipe 17 branches from between the heat source pump 12 in the HP outgoing pipe 14 and the inlet side of the HP unit 7 and is connected to the b port of the four-way valve 18.

更に、タンクユニット３３は、第１給水配管９ａ、第２給水配管９ｂ、給湯配管２１ｃ、中温水取出し配管２１ｂ、給湯用混合弁２２、ふろ用混合弁２３、中温水混合弁４０、第１給湯配管２４、および第２給湯配管２５を有している。第１給水配管９ａの一端は水道等の水源に接続され、第１給水配管９ａの他端には減圧弁３１を介して第２給水配管９ｂおよび第３給水配管９ｃが接続され、これらによって給水管路９が構成されている。第２給水配管９ｂは、途中から分岐して、給湯用混合弁２２の二つの入口のうちの一方と、ふろ用混合弁２３の二つの入口のうちの一方とにそれぞれ接続されている。中温水取出し配管２１ｂは、その一端が貯湯タンク８の中ほどの高さに接続され、他端が中温水混合弁４０の二つの入口のうちの一方に接続されている。この中温水取出し配管２１ｂにより、貯湯タンク８の中ほどに貯留された中温水を取り出して、中温水混合弁４０に供給可能である。中温水混合弁４０の二つの入口のうちの他方は、給湯配管２１ａに接続されている。中温水混合弁４０は、貯湯タンク８の上部から給湯配管２１ａにより取り出された高温水と、貯湯タンク８の中ほどの高さから中温水取出し配管２１ｂにより取り出された中温水との混合比を可変とする機能を有する第１混合部に相当する。中温水混合弁４０の出口には、給湯配管２１ｃの一端が接続されている。給湯配管２１ｃの他端は、途中から分岐して、給湯用混合弁２２の二つの入口のうちの他方と、ふろ用混合弁２３の二つの入口のうちの他方とにそれぞれ接続されている。以下の説明では、中温水混合弁４０から給湯配管２１ｃへ供給される温水を「第１温水」と称する。給湯配管２１ａ、中温水取出し配管２１ｂおよび給湯配管２１ｃにより、給湯管路２１が構成される。 Furthermore, the tank unit 33 includes a first water supply pipe 9a, a second water supply pipe 9b, a hot water supply pipe 21c, an intermediate temperature water extraction pipe 21b, a hot water mixing valve 22, a bath mixing valve 23, an intermediate temperature water mixing valve 40, and a first hot water supply. A pipe 24 and a second hot water supply pipe 25 are provided. One end of the first water supply pipe 9a is connected to a water source such as a water supply, and the other end of the first water supply pipe 9a is connected to the second water supply pipe 9b and the third water supply pipe 9c via the pressure reducing valve 31, thereby supplying water. A conduit 9 is configured. The second water supply pipe 9 b is branched from the middle and connected to one of the two inlets of the hot water supply mixing valve 22 and one of the two inlets of the bath mixing valve 23. One end of the intermediate temperature water discharge pipe 21 b is connected to the middle height of the hot water storage tank 8, and the other end is connected to one of the two inlets of the intermediate temperature water mixing valve 40. The intermediate warm water take-out pipe 21 b can take out the intermediate warm water stored in the middle of the hot water storage tank 8 and supply it to the intermediate warm water mixing valve 40. The other of the two inlets of the intermediate temperature water mixing valve 40 is connected to the hot water supply pipe 21a. The intermediate temperature water mixing valve 40 has a mixing ratio between the high temperature water taken out from the upper part of the hot water storage tank 8 by the hot water supply pipe 21a and the intermediate temperature water taken out from the middle height of the hot water storage tank 8 by the intermediate temperature water extraction pipe 21b. This corresponds to a first mixing unit having a variable function. One end of a hot water supply pipe 21 c is connected to the outlet of the intermediate temperature water mixing valve 40. The other end of the hot water supply pipe 21 c is branched from the middle and connected to the other of the two inlets of the hot water mixing valve 22 and the other of the two inlets of the bath mixing valve 23. In the following description, the warm water supplied from the intermediate warm water mixing valve 40 to the hot water supply pipe 21c is referred to as “first warm water”. The hot water supply pipe 21a is constituted by the hot water supply pipe 21a, the intermediate hot water outlet pipe 21b, and the hot water supply pipe 21c.

給湯用混合弁２２は、中温水混合弁４０から給湯配管２１ｃにより供給される第１温水と、第２給水配管９ｂから供給される低温水との混合比を可変とする機能を有する第２混合部に相当する。給湯用混合弁２２の出口は、第１給湯配管２４の一端に接続されている。以下の説明では、給湯用混合弁２２から第１給湯配管２４へ供給される温水を「第２温水」と称する。第２温水は、第１給湯配管２４から給湯栓３４を経由して、使用者が使用するシャワーやカラン等の蛇口（図示省略）に供給される。本実施の形態１では、中温水混合弁４０（第１混合部）および給湯用混合弁２２（第２混合部）により、貯湯タンク８から供給される温水（高温水、中温水、第１温水）と、水源から供給される低温水とを混合して、第１給湯配管２４へ供給する混合手段が構成される。このような構成により、本実施の形態１では、貯湯タンク８内の中温水を有効に利用することができ、省エネルギー性が向上する。 The hot water supply mixing valve 22 has a function of changing the mixing ratio of the first hot water supplied from the intermediate hot water mixing valve 40 through the hot water supply pipe 21c and the low temperature water supplied from the second water supply pipe 9b. It corresponds to the part. The outlet of the hot water supply mixing valve 22 is connected to one end of the first hot water supply pipe 24. In the following description, the hot water supplied from the hot water supply mixing valve 22 to the first hot water supply pipe 24 is referred to as “second hot water”. The second hot water is supplied from the first hot water supply pipe 24 via the hot water tap 34 to a faucet (not shown) such as a shower or a currant used by the user. In the first embodiment, warm water (high temperature water, medium temperature water, first warm water) supplied from hot water storage tank 8 by medium temperature water mixing valve 40 (first mixing unit) and hot water supply mixing valve 22 (second mixing unit). ) And low-temperature water supplied from a water source, and mixing means for supplying the first hot water supply pipe 24 is configured. With such a configuration, in the first embodiment, the medium temperature water in the hot water storage tank 8 can be used effectively, and the energy saving performance is improved.

ふろ用混合弁２３は、中温水混合弁４０から給湯配管２１ｃにより供給される第１温水と、第２給水配管９ｂから供給される低温水との混合比を可変とする機能を有する。ふろ用混合弁２３の出口は、第２給湯配管２５の一端に接続されている。第２給湯配管２５の途中には、第２給湯配管２５を開閉するふろ用電磁弁２６と、第２給湯配管２５を通る湯の流量を検出するふろ用流量センサ４５とが設けられている。ふろ用混合弁２３から第２給湯配管２５へ供給された温水は、ふろ往き配管２７、ふろ戻り配管２８を経て、浴槽３０に流入する。ふろ用混合弁２３は、貯湯タンク８から供給される温水（第１温水）と、水源から供給される低温水とを混合して、第２給湯配管２５へ供給するふろ用混合部に相当する。以下の説明では、ふろ用混合弁２３から第２給湯配管２５へ供給される温水を「第３温水」と称する。リモコン装置４４が受けた使用者からの指示に基づき、浴槽３０に湯張りする場合あるいは浴槽３０に湯を追加する場合には、制御手段３６は、ふろ用電磁弁２６を開くことにより、浴槽３０へ第３温水を供給する。また、制御手段３６は、ふろ用混合弁２３による第１温水と低温水との混合比を調整することにより、第３温水の温度を、リモコン装置４４で使用者が設定した温度になるように制御する。 The bath mixing valve 23 has a function of changing the mixing ratio of the first hot water supplied from the intermediate hot water mixing valve 40 through the hot water supply pipe 21c and the low temperature water supplied from the second water supply pipe 9b. The outlet of the basin mixing valve 23 is connected to one end of the second hot water supply pipe 25. In the middle of the second hot water supply pipe 25, there are provided a solenoid valve 26 for opening and closing the second hot water supply pipe 25, and a flow sensor 45 for detecting the flow of hot water passing through the second hot water supply pipe 25. The hot water supplied from the bath mixing valve 23 to the second hot water supply pipe 25 flows into the bathtub 30 through the bath forward pipe 27 and the bath return pipe 28. The bath mixing valve 23 corresponds to a bath mixing unit that mixes hot water (first hot water) supplied from the hot water storage tank 8 and low temperature water supplied from a water source and supplies the mixed water to the second hot water supply pipe 25. . In the following description, the hot water supplied from the bath mixing valve 23 to the second hot water supply pipe 25 is referred to as “third hot water”. When filling the bathtub 30 or adding hot water to the bathtub 30 based on an instruction from the user received by the remote control device 44, the control means 36 opens the bath solenoid valve 26 to open the bathtub 30. 3rd hot water is supplied. Further, the control means 36 adjusts the mixing ratio of the first hot water and the low temperature water by the bath mixing valve 23 so that the temperature of the third hot water becomes the temperature set by the user with the remote control device 44. Control.

三方弁１１は、水導出口配管１０とＨＰ往き配管１４とが連通する形態と、温水導出配管２０ｂとＨＰ往き配管１４とが連通する形態と、の２つの流路形態で、タンクユニット３３内の温水の流路を切り替えて使用する。四方弁１８は、ＨＰ戻り配管１５と送湯配管１３とが連通する形態と、ＨＰ戻り配管１５と第１バイパス配管１６とが連通する形態と、第１バイパス配管１６と第２バイパス配管１７とが連通する形態と、送湯配管１３と第２バイパス配管１７とが連通する形態と、の４つの流路形態で、タンクユニット３３内の温水の流路を切り替えて使用する。 The three-way valve 11 has two flow path forms, a form in which the water outlet pipe 10 and the HP outgoing pipe 14 communicate with each other, and a form in which the hot water outlet pipe 20b and the HP outgoing pipe 14 communicate with each other. Switch the hot water flow path. The four-way valve 18 includes a form in which the HP return pipe 15 and the hot water supply pipe 13 communicate with each other, a form in which the HP return pipe 15 and the first bypass pipe 16 communicate with each other, a first bypass pipe 16 and a second bypass pipe 17. Are connected to the hot water supply pipe 13 and the second bypass pipe 17 are connected to each other, and the flow path of the hot water in the tank unit 33 is switched for use.

次に、本実施の形態１の貯湯式給湯機３５の動作について説明する。貯湯式給湯機３５は、第１給湯配管２４への給湯モードとして、次の２つの給湯モードを備える。一つは定温給湯モードであり、もう一つは変温給湯モードである。定温給湯モードは、通常の給湯モードであり、第１給湯配管２４へ供給する第２温水の温度を時間的に一定に制御するモードである。変温給湯モードは、第１給湯配管２４へ供給する第２温水の温度を時間的に変動させることにより、定温給湯モードに比べて全体的な出湯熱量を抑え、省エネルギー効果を発揮させるものである。一般的に、人間の温感は、一定温度状態にあると鈍感になりやすく、ある程度の温度の揺らぎを与えることで、温熱感を得られる効果があることが知られている。変温給湯モードは、この効果を利用したものである。これら各給湯モードは、リモコン装置４４の操作部（図示省略）から、使用者がモード選択することができる。以下、各モードの動作について説明する。 Next, the operation of the hot water storage type water heater 35 of the first embodiment will be described. The hot water storage type water heater 35 includes the following two hot water supply modes as hot water supply modes to the first hot water supply pipe 24. One is a constant temperature hot water supply mode, and the other is a variable temperature hot water supply mode. The constant temperature hot water supply mode is a normal hot water supply mode, in which the temperature of the second hot water supplied to the first hot water supply pipe 24 is controlled to be constant over time. In the variable temperature hot water supply mode, the temperature of the second hot water supplied to the first hot water supply pipe 24 is temporally changed to suppress the overall amount of discharged hot water compared to the constant temperature hot water supply mode, thereby exhibiting an energy saving effect. . In general, it is known that human thermal sensation tends to become insensitive when in a constant temperature state, and that there is an effect of obtaining thermal sensation by giving a certain degree of temperature fluctuation. The variable temperature hot water supply mode utilizes this effect. These hot water supply modes can be selected by the user from the operation unit (not shown) of the remote control device 44. Hereinafter, the operation in each mode will be described.

まず、定温給湯モードについて説明する。使用者がシャワーやカラン等から所望する温度の湯（第２温水）を出湯する際、制御手段３６は、給湯用混合弁２２による第１温水と低温水との混合比を調整し、第１給湯配管２４に設けられた給湯温度センサ３９で検出される第２温水の温度が、リモコン装置４４で使用者が設定した湯温である目標温度になるように、フィードバック制御する。給湯流量は、使用状況の変化（例えば、複数の蛇口を使用している状態から１つになったり、蛇口を絞るなどして流量を減らしたりした場合）により変動する。このとき、制御手段３６は、中温水混合弁４０の混合比に対してはフィードバック制御を行わずに固定し、給湯用混合弁２２の混合比をフィードバック制御することにより、第２温水の温度を目標温度に到達させる。また、制御手段３６は、中温水取出し配管２１ｂにより取り出される中温水の温度が、目標温度よりも高い場合には、中温水取出し配管２１ｂ側が全開で給湯配管２１ａ側が全閉になる、すなわち中温水の混合比が１００％で高温水の混合比が０％になるように、中温水混合弁４０の混合比を予め調整する。また、制御手段３６は、中温水取出し配管２１ｂから取り出される中温水の温度が目標温度に比べて低い場合には、第１温水の温度が目標温度よりも所定温度（例えば５℃）高くなるように、給湯配管２１ａからの高温水と中温水取出し配管２１ｂからの中温水との混合比を中温水混合弁４０により予め調整する。なお、中温水取出し配管２１ｂから取り出される中温水の温度は、貯湯タンク８への中温水取出し配管２１ｂの接続位置と同じ高さに設けられた貯湯温度センサ４２で検出される。あるいは、中温水取出し配管２１ｂに温度センサを設けても良い。また、第１温水の温度は、給湯配管２１ｃに設けられた温度センサ（図示省略）により検出される。 First, the constant temperature hot water supply mode will be described. When the user discharges hot water (second hot water) having a desired temperature from a shower, a currant, etc., the control means 36 adjusts the mixing ratio of the first hot water and the low-temperature water by the hot water supply mixing valve 22 to obtain the first temperature. Feedback control is performed so that the temperature of the second hot water detected by the hot water supply temperature sensor 39 provided in the hot water supply pipe 24 becomes a target temperature that is the hot water temperature set by the user using the remote controller 44. The hot water supply flow rate fluctuates due to changes in usage conditions (for example, when the flow rate is reduced by changing the number of taps to one from a state where a plurality of taps are used, or by reducing the taps). At this time, the control means 36 fixes the mixing ratio of the warm water mixing valve 40 without performing feedback control, and feedback controls the mixing ratio of the hot water mixing valve 22 to thereby control the temperature of the second warm water. Reach the target temperature. In addition, when the temperature of the medium-temperature water taken out by the medium-temperature water take-out pipe 21b is higher than the target temperature, the control unit 36 opens the medium-temperature water take-out pipe 21b side and fully closes the hot water supply pipe 21a side. The mixing ratio of the medium-temperature water mixing valve 40 is adjusted in advance so that the mixing ratio is 100% and the mixing ratio of the high-temperature water is 0%. In addition, when the temperature of the medium-temperature water taken out from the medium-temperature water extraction pipe 21b is lower than the target temperature, the control unit 36 causes the temperature of the first warm water to be higher than the target temperature by a predetermined temperature (for example, 5 ° C.). In addition, the mixing ratio of the high temperature water from the hot water supply pipe 21 a and the medium temperature water from the intermediate temperature water extraction pipe 21 b is adjusted in advance by the intermediate temperature water mixing valve 40. The temperature of the medium-temperature water taken out from the medium-temperature water take-out pipe 21b is detected by a hot water storage temperature sensor 42 provided at the same height as the connection position of the medium-temperature water take-out pipe 21b to the hot water storage tank 8. Alternatively, a temperature sensor may be provided in the intermediate temperature water extraction pipe 21b. Moreover, the temperature of 1st warm water is detected by the temperature sensor (illustration omitted) provided in the hot water supply piping 21c.

次に、変温給湯モードについて説明する。変温給湯モードでは、給湯実行中に中温水混合弁４０の混合比を変動させるように動作させることで、第２温水の温度を変動させる。すなわち、変温給湯モードにおいては、制御手段３６は、給湯実行中に、給湯用混合弁２２の混合比に対してはフィードバック制御を行わずに固定し、中温水混合弁４０での高温水と中温水との混合比を変動させることで、第１温水の温度を変動させる。このため、給湯用混合弁２２が動作を停止していても、給湯用混合弁２２に供給される第１温水の温度が変動することで、給湯用混合弁２２から流出する第２温水の温度が変動する。変温給湯モードでは、第２温水の温度を、定温給湯モードでの目標温度に等しい状態から、この目標温度より数℃低い温度へ低下させた後、また目標温度へ上昇させる、というサイクルを、例えば１０秒程度の周期で繰り返すように、中温水混合弁４０を繰り返し動作させる。変温給湯モードにおける給湯温度の変動幅は、数℃程度であるので、シャワー等の使用者に不快感を与えることはない。一方、給湯温度すなわち第２温水の温度を、目標温度に比べて周期的に低下させるので、使用するエネルギー（貯湯タンク８に貯えた湯の量または蓄熱量）が少なくて済む。このため、定温給湯モードに比べて、省エネルギー効果が発揮される。また、第２温水を例えばシャワー等へ供給する場合、給湯温度が周期的に変動しても、すすぎ性能には影響ないため、シャワー等の使いやすさを維持しつつ、上記の省エネルギー効果が得られる。 Next, the variable temperature hot water supply mode will be described. In the variable temperature hot water supply mode, the temperature of the second hot water is changed by operating the hot water supply valve 40 so as to change the mixing ratio of the intermediate temperature water mixing valve 40 during the hot water supply. That is, in the variable temperature hot water supply mode, the control unit 36 fixes the mixing ratio of the hot water supply mixing valve 22 without performing feedback control during the hot water supply, and the high temperature water in the intermediate hot water mixing valve 40 is fixed. The temperature of the first warm water is varied by varying the mixing ratio with the medium temperature water. For this reason, even if the hot water mixing valve 22 stops operating, the temperature of the first hot water supplied to the hot water mixing valve 22 fluctuates, so that the temperature of the second hot water flowing out of the hot water mixing valve 22 is changed. Fluctuates. In the variable temperature hot water supply mode, a cycle in which the temperature of the second hot water is decreased from a state equal to the target temperature in the constant temperature hot water supply mode to a temperature several degrees lower than the target temperature and then increased to the target temperature. For example, the intermediate temperature water mixing valve 40 is repeatedly operated so as to repeat at a cycle of about 10 seconds. Since the fluctuation range of the hot water supply temperature in the variable temperature hot water supply mode is about several degrees Celsius, it does not give an unpleasant feeling to a user such as a shower. On the other hand, since the hot water supply temperature, that is, the temperature of the second hot water is periodically lowered as compared with the target temperature, less energy is used (the amount of hot water stored in the hot water storage tank 8 or the amount of stored heat). For this reason, an energy saving effect is exhibited compared with the constant temperature hot water supply mode. In addition, when the second hot water is supplied to, for example, a shower, the rinsing performance is not affected even if the hot water temperature fluctuates periodically. Therefore, the above energy saving effect is obtained while maintaining the ease of use of the shower. It is done.

なお、変温給湯モードにおいて、目標温度から低温側への変動させる温度幅、サイクルの周期などの値を、使用者がリモコン装置４４で任意に設定可能に構成してもよい。また、上述の例では、変温給湯モードにおける温度変動を、定温給湯モードの目標温度を基準として低温側に変動させるものとして説明したが、例えば、温度変動の基準を定温給湯モードの目標温度よりも例えば３℃程度低い温度とし、その基準温度から上下に例えば２〜３℃の幅で変動させるように構成してもよい。このような構成によれば、使用者は出湯温度の揺らぎをより一層感じることにはなるが、それが直ちに不快感となることはなく、更なる省エネルギー効果が発揮される。 In the variable temperature hot water supply mode, the user may arbitrarily set values such as a temperature range to be changed from the target temperature to the low temperature side and a cycle period by the remote control device 44. In the above-described example, the temperature fluctuation in the variable temperature hot water supply mode has been described as changing to the low temperature side with respect to the target temperature of the constant temperature hot water supply mode. For example, the reference of the temperature fluctuation is based on the target temperature of the constant temperature hot water supply mode. For example, the temperature may be lower by about 3 ° C., and may be configured to fluctuate in a range of, for example, 2 to 3 ° C. above and below the reference temperature. According to such a structure, although a user will feel the fluctuation of the tapping temperature more, it does not immediately become uncomfortable and a further energy saving effect is exhibited.

上述したように、定温給湯モードでは、中温水混合弁４０の混合比に対してはフィードバック制御を行わずに固定し、給湯用混合弁２２の混合比をフィードバック制御する。このため、定温給湯モードでは、中温水混合弁４０の動作頻度に比べて、給湯用混合弁２２の動作頻度が高くなる。これに対し、変温給湯モードでは、給湯用混合弁２２の混合比は繰り返し変動させることなく固定し、中温水混合弁４０の混合比を繰り返し変動させることで、第２温水の温度を変動させる。このため、変温給湯モードでは、給湯用混合弁２２の動作頻度に比べて、中温水混合弁４０の動作頻度が高くなる。このようなことから、本実施の形態１によれば、中温水混合弁４０および給湯用混合弁２２の稼動時間や稼動量が何れか一方に偏ることがないので、中温水混合弁４０および給湯用混合弁２２の双方の長寿命化を図ることができる。よって、信頼性の高い貯湯式給湯機３５を提供することが可能となる。 As described above, in the constant temperature hot water supply mode, the mixing ratio of the medium temperature water mixing valve 40 is fixed without performing feedback control, and the mixing ratio of the hot water mixing valve 22 is feedback controlled. For this reason, in the constant temperature hot water supply mode, the operation frequency of the hot water mixing valve 22 is higher than the operation frequency of the medium temperature water mixing valve 40. On the other hand, in the variable temperature hot water supply mode, the mixing ratio of the hot water mixing valve 22 is fixed without being repeatedly changed, and the temperature of the second hot water is changed by repeatedly changing the mixing ratio of the intermediate temperature water mixing valve 40. . For this reason, in the variable temperature hot water supply mode, the operation frequency of the intermediate temperature water mixing valve 40 is higher than the operation frequency of the hot water supply mixing valve 22. For this reason, according to the first embodiment, the operation time and the operation amount of the intermediate warm water mixing valve 40 and the hot water supply mixing valve 22 are not biased to either one. The service life of both the mixing valve 22 can be extended. Therefore, it is possible to provide a highly reliable hot water storage type water heater 35.

以下の説明では、第２給湯配管２５へ第３温水を供給せずに第１給湯配管２４へ第２温水を供給している状態を「単独給湯状態」と称する。単独給湯状態は、浴槽３０へ第３温水を供給せず、シャワーやカラン等の蛇口へ第２温水を供給している状態である。また、第１給湯配管２４へ第２温水を供給すると同時に、第２給湯配管２５へ第３温水を供給している状態を「同時給湯状態」と称する。同時給湯状態は、シャワーやカラン等の蛇口への第２温水と、浴槽３０への第３温水とを同時に供給している状態である。 In the following description, a state in which the second hot water is supplied to the first hot water supply pipe 24 without supplying the third hot water to the second hot water supply pipe 25 is referred to as a “single hot water supply state”. The single hot water supply state is a state in which the third hot water is not supplied to the bathtub 30 and the second hot water is supplied to a faucet such as a shower or a currant. The state in which the second hot water is supplied to the first hot water supply pipe 24 and the third hot water is supplied to the second hot water supply pipe 25 is referred to as a “simultaneous hot water supply state”. The simultaneous hot water supply state is a state in which the second hot water to the faucet such as a shower or currant and the third hot water to the bathtub 30 are simultaneously supplied.

単独給湯状態から同時給湯状態へ移行した場合、すなわち、シャワーやカラン等の蛇口のみへ第２温水を供給している状態から、ふろ用電磁弁２６が開いて浴槽３０への第３温水の供給が開始した場合には、給湯管路２１および給水管路９の湯水の流量が急激に変化する。その結果、過渡的な変化に対して給湯用混合弁２２あるいは中温水混合弁４０の動作が正確に追従することが困難になり、シャワーやカラン等の蛇口へ供給する第２温水の温度が変動する場合がある。特に、変温給湯モードで第２温水を供給している場合には、中温水混合弁４０が混合比を周期的に変動させるように繰り返し動作をしていることから、流量の急激な変化に伴って第１温水の温度がより大きく変動し、第２温水の温度変動もより大きくなりやすい。そのため、変温給湯モードによる単独給湯状態から、ふろ用電磁弁２６が開いて、同時給湯状態へ移行した場合には、第２温水の温度変動が過大になり、シャワーやカラン等の蛇口の使用者に不快感を与える可能性がある。 When shifting from the single hot water supply state to the simultaneous hot water supply state, that is, from the state in which the second hot water is supplied only to the faucet such as a shower or currant, the bath solenoid valve 26 is opened and the third hot water is supplied to the bathtub 30 When is started, the flow rates of hot water in the hot water supply pipe line 21 and the hot water supply pipe line 9 change abruptly. As a result, it becomes difficult for the operation of the hot water mixing valve 22 or the intermediate hot water mixing valve 40 to accurately follow the transient change, and the temperature of the second hot water supplied to the faucet such as a shower or currant fluctuates. There is a case. In particular, when the second hot water is supplied in the variable temperature hot water supply mode, the intermediate hot water mixing valve 40 repeatedly operates so as to periodically change the mixing ratio. Along with this, the temperature of the first hot water fluctuates more and the temperature fluctuation of the second hot water tends to become larger. Therefore, when the bath solenoid valve 26 is opened from the single hot water supply state in the variable temperature hot water supply mode and the state is shifted to the simultaneous hot water supply state, the temperature variation of the second hot water becomes excessive, and the use of a faucet such as a shower or currant is used. May cause discomfort to the person.

上記のような問題を解決するため、本実施の形態１では、変温給湯モードによる単独給湯状態から同時給湯状態へ移行する要求が生じた場合には、制御手段３６は、第２給湯配管２５への第３温水の供給を開始する前、すなわちふろ用電磁弁２６を開く前に、変温給湯モードから定温給湯モードへ切り替えるように制御する。そして、制御手段３６は、定温給湯モードへ切り替えた後、ふろ用電磁弁２６を開いて、第２給湯配管２５への第３温水の供給を開始する。定温給湯モードの場合には、給湯管路２１および給水管路９の湯水の流量が急変しても、第２温水の温度変動は比較的小さい。このため、本実施の形態１によれば、単独給湯状態から同時給湯状態へ移行した際の第２温水の温度変動が過大になることを確実に抑制することができる。このため、シャワーやカラン等の蛇口の使用者に不快感を与えることを確実に抑制することができ、使いやすさを維持することができる。 In order to solve the problems as described above, in the first embodiment, when a request to shift from the single hot water supply state to the simultaneous hot water supply state in the variable temperature hot water supply mode is generated, the control means 36 causes the second hot water supply pipe 25 to Control is performed so as to switch from the variable temperature hot water supply mode to the constant temperature hot water supply mode before starting the supply of the third hot water to the water heater, that is, before opening the bath solenoid valve 26. Then, after switching to the constant temperature hot water supply mode, the control means 36 opens the bath solenoid valve 26 and starts supplying the third hot water to the second hot water supply pipe 25. In the constant temperature hot water supply mode, even if the hot water flow rates in the hot water supply pipe 21 and the water supply pipe 9 change suddenly, the temperature fluctuation of the second hot water is relatively small. For this reason, according to this Embodiment 1, it can suppress reliably that the temperature fluctuation of 2nd warm water at the time of transfering from a single hot water supply state to a simultaneous hot water supply state becomes excessive. For this reason, it can suppress reliably giving a user discomfort to faucets, such as a shower and a currant, and can maintain usability.

上述したようにして、単独給湯状態から同時給湯状態へ移行した後、第２給湯配管２５への第３温水の供給が終了した場合、すなわち同時給湯状態から単独給湯状態へ戻った場合には、制御手段３６は、定温給湯モードから変温給湯モードへ戻すように制御する。その際、制御手段３６は、第２給湯配管２５への第３温水の供給が終了した時点、すなわちふろ用電磁弁２６を閉じた時点から、予め設定された時間（例えば１０秒）が経過した後に、定温給湯モードから変温給湯モードへ切り替えることが望ましい。このような制御により、変温給湯モードへ切り替えた後に第２温水の温度変動が過大になることを確実に抑制することができ、使用者に不快感を与えることを確実に抑制しつつ、変温給湯モードの省エネルギー効果を発揮させることができる。 As described above, after the transition from the single hot water supply state to the simultaneous hot water supply state, when the supply of the third hot water to the second hot water supply pipe 25 is completed, that is, when the simultaneous hot water supply state returns to the single hot water supply state, The control means 36 controls to return from the constant temperature hot water supply mode to the variable temperature hot water supply mode. At that time, the control means 36 has passed a preset time (for example, 10 seconds) from the time when the supply of the third hot water to the second hot water supply pipe 25 is completed, that is, the time when the bath solenoid valve 26 is closed. It is desirable to switch from the constant temperature hot water supply mode to the variable temperature hot water supply mode later. By such control, it is possible to reliably suppress the temperature fluctuation of the second hot water after switching to the variable temperature hot water supply mode, and to reliably prevent the user from feeling uncomfortable while changing the temperature. The energy saving effect of the hot water supply mode can be exhibited.

また、貯湯式給湯機３５は、第１給湯配管２４へ第２温水を供給したタイミング、すなわちシャワーやカラン等の蛇口へ給湯したタイミングを記憶する給湯タイミング記憶手段と、給湯用混合弁２２、ふろ用混合弁２３および中温水混合弁４０の故障の有無を自動的に診断する診断手段とを備えていることが望ましい。本実施の形態１では、制御手段３６が、過去の一定日数（例えば２週間）において、第１給湯配管２４への給湯要求があった場合、その給湯要求があった時刻および給湯時間を記憶する。制御手段３６は、定温給湯モードであるか変温給湯モードであるかにかかわらず、第１給湯配管２４へ第２温水を供給したタイミングを記憶する。制御手段３６は、その記憶した給湯要求の時刻および給湯時間に基づいて、給湯要求が発生する可能性の低いタイミング（例えば、深夜２時頃）を選択し、給湯用混合弁２２、ふろ用混合弁２３および中温水混合弁４０の自動故障診断モードを実施する。本実施の形態１では、給湯用混合弁２２、ふろ用混合弁２３および中温水混合弁４０の動力にはステッピングモータが使用されており、制御手段３６は、給湯用混合弁２２、ふろ用混合弁２３および中温水混合弁４０の各々について、任意の開度をフィードバック信号により検出することができる。制御手段３６は、自動故障診断モードにおいて、このフィードバック信号に基づき、給湯用混合弁２２、ふろ用混合弁２３および中温水混合弁４０の各々の動作が正常であるか否かを判定することができる。制御手段３６は、給湯用混合弁２２、ふろ用混合弁２３、中温水混合弁４０の何れかが故障していると判断した場合は、その旨をリモコン装置４４に表示し、速やかな対応を使用者に求めるよう報知することが望ましい。 The hot water storage type water heater 35 includes a hot water supply timing storage means for storing the timing at which the second hot water is supplied to the first hot water supply pipe 24, that is, the timing at which hot water is supplied to a faucet such as a shower or currant, the hot water mixing valve 22, the bath It is desirable to provide diagnostic means for automatically diagnosing the presence or absence of failure of the mixing valve 23 and the warm water mixing valve 40. In the first embodiment, when there is a hot water supply request to the first hot water supply pipe 24 in the past certain number of days (for example, two weeks), the control means 36 stores the time and hot water supply time when the hot water supply request is made. . The control means 36 stores the timing at which the second hot water is supplied to the first hot water supply pipe 24 regardless of the constant temperature hot water supply mode or the variable temperature hot water supply mode. Based on the stored hot water supply request time and hot water supply time, the control means 36 selects a timing at which the hot water supply request is unlikely to occur (for example, around midnight), and mixes the hot water mixing valve 22 and the bath. The automatic failure diagnosis mode of the valve 23 and the medium hot water mixing valve 40 is performed. In the first embodiment, a stepping motor is used as the power for the hot water mixing valve 22, the bath mixing valve 23, and the intermediate temperature water mixing valve 40, and the control means 36 uses the hot water mixing valve 22, the bath mixing. For each of the valve 23 and the intermediate warm water mixing valve 40, an arbitrary opening degree can be detected by a feedback signal. In the automatic failure diagnosis mode, the control means 36 determines whether or not the operation of each of the hot water mixing valve 22, the bath mixing valve 23, and the intermediate hot water mixing valve 40 is normal based on this feedback signal. it can. When the control means 36 determines that any one of the hot water mixing valve 22, the bath mixing valve 23, and the medium hot water mixing valve 40 is out of order, the control means 36 displays that fact on the remote control device 44 and promptly responds. It is desirable to notify the user to ask.

制御手段３６は、以下のような制御を更に行っても良い。変温給湯モードの動作時に、第１給湯配管２４に設けられた給湯温度センサ３９により検出される第２温水の温度の変動幅が、予め設定された温度幅（例えば３℃）にならないような場合には、中温水混合弁４０が正常に動作していないと考えられる。そこで、制御手段３６は、変温給湯モードによる給湯開始後、給湯温度センサ３９により検出される第２温水の温度の変動幅が、予め設定された制限時間内に、予め設定された温度幅にならないような場合には、中温水混合弁４０が故障したと判断して、中温水混合弁４０に代えて、給湯用混合弁２２の混合比を繰り返し変動させるように制御しても良い。このような制御によれば、中温水混合弁４０が万一故障した場合であっても、変温給湯モードにおいて第２温水の温度を変動させることが可能となる。なお、制御手段３６は、中温水混合弁４０が故障したと判断した場合には、リモコン装置４４に、中温水混合弁４０が故障している旨を表示し、速やかな対応を使用者に求めるよう報知することが望ましい。 The control means 36 may further perform the following control. During the operation in the variable temperature hot water supply mode, the fluctuation range of the temperature of the second hot water detected by the hot water supply temperature sensor 39 provided in the first hot water supply pipe 24 does not become a preset temperature range (for example, 3 ° C.). In this case, it is considered that the intermediate warm water mixing valve 40 is not operating normally. Therefore, after starting the hot water supply in the variable temperature hot water supply mode, the control means 36 sets the temperature fluctuation range of the second hot water detected by the hot water temperature sensor 39 to a preset temperature range within a preset time limit. If this is not the case, it may be determined that the intermediate temperature water mixing valve 40 has failed, and instead of the intermediate temperature water mixing valve 40, the mixing ratio of the hot water supply mixing valve 22 may be controlled to be repeatedly varied. According to such control, even if the intermediate warm water mixing valve 40 is broken, the temperature of the second warm water can be changed in the variable temperature hot water supply mode. When the control unit 36 determines that the intermediate temperature water mixing valve 40 has failed, the control unit 36 displays on the remote control device 44 that the intermediate temperature water mixing valve 40 has failed, and prompts the user for prompt action. It is desirable to notify such.

また、制御手段３６は、定温給湯モードによる給湯開始後、給湯温度センサ３９により検出される第２温水の温度が、予め設定された制限時間内に目標温度に到達しない場合には、給湯用混合弁２２が故障したと判断して、給湯用混合弁２２に代えて中温水混合弁４０の混合比をフィードバック制御等で調整することにより、第２温水の温度を目標温度に到達させるように制御しても良い。このような制御によれば、給湯用混合弁２２が万一故障した場合であっても、第２温水の温度を目標温度に到達させることが可能となる。なお、制御手段３６は、給湯用混合弁２２が故障したと判断した場合には、リモコン装置４４に、給湯用混合弁２２が故障している旨を表示し、速やかな対応を使用者に求めるよう報知することが望ましい。 In addition, after the start of hot water supply in the constant temperature hot water supply mode, the control means 36 mixes for hot water supply when the temperature of the second hot water detected by the hot water supply temperature sensor 39 does not reach the target temperature within a preset time limit. Control that the temperature of the second hot water reaches the target temperature by determining that the valve 22 has failed and adjusting the mixing ratio of the intermediate temperature water mixing valve 40 instead of the hot water mixing valve 22 by feedback control or the like. You may do it. According to such control, even if the hot water supply mixing valve 22 breaks down, the temperature of the second hot water can be made to reach the target temperature. When the control unit 36 determines that the hot water supply mixing valve 22 has failed, the control unit 36 displays on the remote control device 44 that the hot water supply mixing valve 22 has failed, and prompts the user for prompt action. It is desirable to notify such.

実施の形態２．
次に、本発明の実施の形態２について説明するが、上述した実施の形態１との相違点を中心に説明し、同一部分または相当部分は同一符号を付し説明を省略する。本実施の形態２の貯湯式給湯機３５の構成図は、実施の形態１と同様であるので、省略する。 Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described, focusing on the differences from the first embodiment described above, and the same or corresponding parts will be denoted by the same reference numerals and description thereof will be omitted. Since the block diagram of the hot water storage type hot water supply apparatus 35 of this Embodiment 2 is the same as that of Embodiment 1, it abbreviate | omits.

前述した実施の形態１では、変温給湯モードによる単独給湯状態から同時給湯状態へ移行する要求が生じた場合に、制御手段３６は、第２給湯配管２５への第３温水の供給を開始する前、すなわちふろ用電磁弁２６を開く前に、変温給湯モードから定温給湯モードへ切り替えるように制御する。 In the first embodiment described above, the control means 36 starts supplying the third hot water to the second hot water supply pipe 25 when a request for shifting from the single hot water supply state to the simultaneous hot water supply state in the variable temperature hot water supply mode occurs. Control is performed so as to switch from the variable temperature hot water supply mode to the constant temperature hot water supply mode before the opening electromagnetic valve 26 is opened.

これに対し、本実施の形態２では、変温給湯モードによる単独給湯状態から同時給湯状態へ移行する要求が生じた場合に、制御手段３６は、第２給湯配管２５への第３温水の供給を開始する前、すなわちふろ用電磁弁２６を開く前に、変温給湯モードのまま、第２温水の温度変動の周期を、通常の周期より短い周期に切り替える。例えば、制御手段３６は、変温給湯モードによる第２温水の温度変動の通常の周期が１０秒である場合には、５秒の周期で第２温水の温度が変動するように制御する。制御手段３６は、そのようにして変温給湯モードのまま第２温水の温度変動の周期を短くした後、ふろ用電磁弁２６を開いて、第２給湯配管２５への第３温水の供給を開始する。変温給湯モードの第２温水の温度変動の周期を短くした場合には、配管内で第２温水の高温部分と低温部分とが短い長さで交互に並ぶ。このため、第２温水が、第１給湯配管２４と、給湯栓３４と、給湯栓３４に接続された外部配管（図示省略）とを通って、シャワーやカラン等の蛇口に到達するまでの間に、第２温水の高温部分と低温部分とが配管内で十分に混合される。そのため、給湯用混合弁２２から流出する第２温水の温度変動に比べて、シャワーやカラン等の蛇口から流出する第２温水の温度変動は小さくなる。このようなことから、本実施の形態２では、同時給湯状態へ移行する前に変温給湯モードの第２温水の温度変動の周期を短くすることにより、同時給湯状態への移行後、シャワーやカラン等の蛇口から流出する第２温水の温度変動が過大になることを確実に抑制することができる。よって、シャワーやカラン等の蛇口の使用者に不快感を与えることを確実に抑制することができ、使いやすさを維持することができる。また、本実施の形態２では、同時給湯状態においても変温給湯モードを維持することができるので、実施の形態１に比べて更に省エネルギー性が向上する。なお、変温給湯モードの第２温水の温度変動の周期を短くするときの周期の値は、シャワーやカラン等の蛇口から流出する第２温水の温度変動の大きさを十分に抑制することができるように、実験に基づいて最適な時間を設定することが好ましい。 On the other hand, in this Embodiment 2, when the request | requirement which transfers to the simultaneous hot water supply state from the single hot water supply state by variable temperature hot water supply mode arises, the control means 36 supplies the 3rd hot water to the 2nd hot water supply piping 25. Is started, that is, before the bathing solenoid valve 26 is opened, the temperature variation cycle of the second hot water is switched to a cycle shorter than the normal cycle in the variable temperature hot water supply mode. For example, when the normal cycle of the temperature variation of the second hot water in the variable temperature hot water supply mode is 10 seconds, the control unit 36 performs control so that the temperature of the second hot water varies at a cycle of 5 seconds. The control means 36 shortens the temperature fluctuation cycle of the second hot water in the variable temperature hot water supply mode as described above, and then opens the bath solenoid valve 26 to supply the third hot water to the second hot water supply pipe 25. Start. When the temperature fluctuation cycle of the second hot water in the variable temperature hot water supply mode is shortened, the high temperature portion and the low temperature portion of the second hot water are alternately arranged in a short length in the pipe. For this reason, the second hot water passes through the first hot water supply pipe 24, the hot water tap 34, and an external pipe (not shown) connected to the hot water tap 34 until it reaches a faucet such as a shower or currant. In addition, the high temperature portion and the low temperature portion of the second warm water are sufficiently mixed in the pipe. Therefore, the temperature fluctuation of the second hot water flowing out from the faucet such as a shower or currant is smaller than the temperature fluctuation of the second hot water flowing out from the hot water mixing valve 22. For this reason, in the present second embodiment, the period of the temperature variation of the second hot water in the variable temperature hot water supply mode is shortened before the transition to the simultaneous hot water supply state. It is possible to reliably suppress the temperature fluctuation of the second hot water flowing out from the faucet such as a curan. Therefore, it is possible to reliably suppress discomfort for a user of a faucet such as a shower or a currant, and maintain ease of use. Further, in the second embodiment, since the variable temperature hot water supply mode can be maintained even in the simultaneous hot water supply state, the energy saving performance is further improved as compared with the first embodiment. In addition, the value of the period when shortening the period of the temperature fluctuation of the second hot water in the variable temperature hot water supply mode can sufficiently suppress the magnitude of the temperature fluctuation of the second hot water flowing out from the faucet such as a shower or currant. It is preferable to set an optimal time based on experiments so that it can be performed.

本実施の形態２では、単独給湯状態から同時給湯状態へ移行した後、第２給湯配管２５への第３温水の供給が終了した場合、すなわち同時給湯状態から単独給湯状態へ戻った場合には、制御手段３６は、変温給湯モードの第２温水の温度変動の周期を、同時給湯状態へ移行する前に短くした周期から、元の通常の周期へ戻すように制御する。その際、制御手段３６は、第２給湯配管２５への第３温水の供給が終了した時点、すなわちふろ用電磁弁２６を閉じた時点から、予め設定された時間（例えば１０秒）が経過した後に、変温給湯モードの第２温水の温度変動の周期を、短くした周期から元の通常の周期へ切り替えることが望ましい。このような制御によれば、変温給湯モードの第２温水の温度変動の周期を元の通常の周期へ戻した後に、第２温水の温度変動が過大になることを確実に抑制することができる。よって、使用者に不快感を与えることを確実に抑制しつつ、変温給湯モードの省エネルギー効果を十分に発揮させることができる。 In the second embodiment, after the transition from the single hot water supply state to the simultaneous hot water supply state, when the supply of the third hot water to the second hot water supply pipe 25 is completed, that is, when the simultaneous hot water supply state returns to the single hot water supply state. The control means 36 performs control so that the cycle of the temperature variation of the second hot water in the variable temperature hot water supply mode is restored from the cycle shortened before shifting to the simultaneous hot water supply state to the original normal cycle. At that time, the control means 36 has passed a preset time (for example, 10 seconds) from the time when the supply of the third hot water to the second hot water supply pipe 25 is completed, that is, the time when the bath solenoid valve 26 is closed. It is desirable to switch the period of temperature fluctuation of the second hot water in the variable temperature hot water supply mode from the shortened period to the original normal period later. According to such control, it is possible to reliably suppress the temperature fluctuation of the second hot water from becoming excessive after returning the temperature fluctuation period of the second hot water in the variable temperature hot water supply mode to the original normal period. it can. Therefore, it is possible to sufficiently exhibit the energy saving effect of the variable temperature hot water supply mode while reliably suppressing discomfort to the user.

以上、本発明の実施の形態について説明したが、本発明は、上述した実施の形態１，２に限定されるものではない。例えば、本発明では、中温水混合弁４０が無くても良い。その場合には、変温給湯モードにおいて、給湯用混合弁２２の混合比を繰り返し変動させることにより、第２温水の温度を周期的に変動させることができる。また、上述した実施の形態１，２では、第２給湯配管２５へ供給された温水が浴槽３０に供給されるものとして説明したが、本発明は、第２給湯配管２５へ供給された温水が浴槽３０以外の需要側へ供給される場合にも同様に適用可能である。 As mentioned above, although embodiment of this invention was described, this invention is not limited to Embodiment 1, 2 mentioned above. For example, in the present invention, the intermediate temperature water mixing valve 40 may be omitted. In that case, in the variable temperature hot water supply mode, the temperature of the second hot water can be periodically changed by repeatedly changing the mixing ratio of the hot water mixing valve 22. In the first and second embodiments described above, the hot water supplied to the second hot water supply pipe 25 has been described as being supplied to the bathtub 30, but in the present invention, the hot water supplied to the second hot water supply pipe 25 is The same applies to the case of supplying to the demand side other than the bathtub 30.

また、本発明では、変温給湯モードにおいて、第２温水の流量を周期的に変動させてもよい。その場合、第２温水の流量の変動周期と、第２温水の温度の変動周期とが、異なっていても良いし、同じでも良い。 Moreover, in this invention, you may change the flow volume of 2nd warm water periodically in variable temperature hot water supply mode. In that case, the fluctuation cycle of the flow rate of the second hot water and the fluctuation cycle of the temperature of the second hot water may be different or the same.

１圧縮機、３水冷媒熱交換器、４膨張弁、５冷媒配管、６空気熱交換器、７ＨＰユニット、８貯湯タンク、８ａ水導入口、８ｂ水導出口、８ｃ温水導入口、８ｄ温水導入出口、９給水管路、９ａ第１給水配管、９ｂ第２給水配管、９ｃ第３給水配管、１０水導出口配管、１１三方弁、１２熱源ポンプ、１３送湯配管、１４ＨＰ往き配管、１５ＨＰ戻り配管、１６第１バイパス配管、１７第２バイパス配管、１８四方弁、２０利用側熱交換器、２０ａ温水導入配管、２０ｂ温水導出配管、２１給湯管路、２１ａ給湯配管、２１ｂ中温水取出し配管、２１ｃ給湯配管、２２給湯用混合弁、２３ふろ用混合弁、２４第１給湯配管、２５第２給湯配管、２６ふろ用電磁弁、２７ふろ往き配管、２８ふろ戻り配管、２９ふろ循環ポンプ、３０浴槽、３１減圧弁、３３タンクユニット、３４給湯栓、３５貯湯式給湯機、３６制御手段、３７ふろ往き温度センサ、３８ふろ戻り温度センサ、３９給湯温度センサ、４０中温水混合弁、４１，４２，４３貯湯温度センサ、４４リモコン装置、４５ふろ用流量センサ DESCRIPTION OF SYMBOLS 1 Compressor, 3 Water refrigerant | coolant heat exchanger, 4 Expansion valve, 5 Refrigerant piping, 6 Air heat exchanger, 7 HP unit, 8 Hot water storage tank, 8a Water inlet, 8b Water outlet, 8c Hot water inlet, 8d Hot water Inlet / outlet, 9 water supply pipe, 9a 1st water supply pipe, 9b 2nd water supply pipe, 9c 3rd water supply pipe, 10 water outlet pipe, 11 three-way valve, 12 heat source pump, 13 hot water supply pipe, 14 HP outgoing pipe, 15 HP return pipe, 16 1st bypass pipe, 17 2nd bypass pipe, 18 four-way valve, 20 utilization side heat exchanger, 20a hot water introduction pipe, 20b hot water outlet pipe, 21 hot water supply pipe, 21a hot water supply pipe, 21b medium hot water Extraction piping, 21c hot water supply piping, 22 hot water mixing valve, 23 bath mixing valve, 24 first hot water piping, 25 second hot water piping, 26 bath solenoid valve, 27 bath piping, 2 Bath return pipe, 29 bath circulation pump, 30 bathtub, 31 pressure reducing valve, 33 tank unit, 34 hot water tap, 35 hot water storage type hot water heater, 36 control means, 37 bath trip temperature sensor, 38 bath return temperature sensor, 39 hot water temperature sensor , 40 Medium hot water mixing valve, 41, 42, 43 Hot water storage temperature sensor, 44 Remote control device, 45 Flow sensor for bath

Claims

A hot water storage tank for storing hot water,
Mixing means for mixing hot water supplied from the hot water storage tank and low temperature water supplied from a water source, and supplying the mixed water to the first hot water supply pipe;
A second hot water supply pipe for sending hot water supplied from the hot water storage tank to the demand side;
The constant temperature hot water supply mode for controlling the mixing means so that the temperature of the hot water supplied to the first hot water supply pipe is constant, and the temperature of the hot water supplied to the first hot water supply pipe is periodically changed. Control means for switching between the variable temperature hot water supply mode for controlling the mixing means;
With
The control means supplies hot water to the second hot water supply pipe from a state in which hot water is supplied to the first hot water supply pipe in the variable temperature hot water supply mode without supplying hot water to the second hot water supply pipe. When starting, a hot water storage system that switches from the variable temperature hot water supply mode to the constant temperature hot water supply mode prior to the start, or shortens the period of the periodic fluctuation of the variable temperature hot water supply mode from the original cycle Water heater.

The control means switches from the variable temperature hot water supply mode to the constant temperature hot water supply mode, or shortens the temperature fluctuation cycle of the hot water in the variable temperature hot water supply mode, and then supplies hot water to the second hot water supply pipe. In the case where the hot water supply to the second hot water supply pipe is completed in the case of the start, after a preset time has elapsed since the end, the constant temperature hot water supply mode is returned to the variable temperature hot water supply mode, Alternatively, the hot water storage type hot water heater according to claim 1, wherein the period of the periodic fluctuation in the temperature-variable hot water supply mode is returned to the original period.

Hot water supply timing storage means for storing the timing of supplying hot water to the first hot water supply pipe;
Based on the timing stored in the hot water supply timing storage means, a diagnostic means for diagnosing the presence or absence of a failure of the mixing means at a timing with a low possibility of supplying hot water to the first hot water supply pipe;
A hot water storage type water heater according to claim 1 or 2.

The mixing means includes
A first mixing unit that varies a mixing ratio of high-temperature water taken out from the upper part of the hot water storage tank and medium hot water taken out from an intermediate part between the upper part and the lower part in the vertical direction of the hot water storage tank;
A second mixing unit for changing a mixing ratio between the first hot water supplied from the first mixing unit and the low-temperature water supplied from the water source;
The hot water storage type water heater according to any one of claims 1 to 3.

The second hot water supply pipe is a pipe that sends hot water to the bathtub side,
The hot water storage according to any one of claims 1 to 4, further comprising a bath mixing unit that mixes hot water supplied from the hot water storage tank and low temperature water supplied from a water source and supplies the mixed water to the second hot water supply pipe. Type water heater.