JP2011145010A - Storage water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a storage water heater including a cleaning function to remove waste (solid matter) accumulated in a passage within a heat exchanger on a bathtub water circulation circuit during reheating. <P>SOLUTION: The storage water heater includes a hot water storage tank 22 storing hot water to be supplied to a bathtub 2, and the heat exchanger 32 exchanging heat between bathtub water made to flow in the bathtub water circulation circuit 36 and tank hot water made to flow in a tank circulation circuit 31. The storage water heater further includes an electric change-over valve 41 performing change-over between a route during normal reheating (first flow passage form) where the bathtub water is made to flow from a second water introduction port 32b side toward a second water leading-out port 32d side in the heat exchanger 32 and a route during backflow cleaning (second flow passage form) where the bathtub water is made to flow from the second water leading-out port 32d side toward the second water introduction port 32b side which is a route opposite to the route during normal reheating as the flow path mode of the bathtub water flowing through the bathtub circulation circuit 36. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hot water storage type hot water heater having a bath-chasing function.

  Conventionally, for example, Patent Literature 1 discloses an exhaust heat recovery apparatus for bathhouses that effectively uses the exhaust heat of hot wastewater discharged from a bathhouse or a bathtub. More specifically, this conventional exhaust heat recovery apparatus performs exhaust heat recovery using a plate heat exchanger.

JP-A-8-61777

  By the way, there is known a hot water storage type hot water heater having a reheating function including a heat exchanger for providing heat exchange between bathtub water flowing through the bathtub water circulation circuit and hot water stored in the hot water storage tank. It has been. When garbage such as hair enters the passage in the heat exchanger for reheating of such a hot water storage type water heater, the waste accumulates in the passage on the inlet side in the heat exchanger, and the bath water circulates during reheating. There was a problem that the flow rate of the bathtub water flowing through the circuit was reduced.

  The present invention has been made in order to solve the above-described problems, and has a cleaning function for removing dust (solid matter) that accumulates in the passage in the heat exchanger on the bathtub water circulation circuit when it is retreated. An object is to provide a hot water heater.

  A hot water storage type water heater according to the present invention has a hot water storage tank for storing hot water to be supplied to a bathtub, and a tank hot water circulation circuit that connects between an upper portion of the hot water storage tank and a lower portion of the hot water storage tank, from above the hot water storage tank. Tank hot water circulation means for circulating the hot water coming out to the lower part of the hot water storage tank, bathtub water circulation means for circulating the bathtub water in the bathtub, and bathtub water flowing in the bathtub water circulation circuit. And a heat exchanger for exchanging heat between the tank hot water flowing in the tank hot water circulation circuit and a flow path form of the bath water flowing in the bath water circulation circuit, from the bath water side first entrance / exit side of the heat exchanger to the bath water side second The 1st flow path form in which bathtub water flows toward the entrance / exit side, and the 2nd flow through which bathtub water flows toward the bathtub water side 1st entrance / exit side from the bathtub water side 2nd entrance / exit side contrary to the 1st flow path form Channel switching to switch between road types Those with a stage, a.

  According to the present invention, it is possible to provide a hot water storage type hot water heater having a cleaning function for removing dust (solid matter) accumulated in the passage in the heat exchanger on the bathtub water circulation circuit.

It is a circuit block diagram of the hot water storage type water heater in Embodiment 1 of this invention. It is a figure (A) for explaining two channel forms of bathtub water circulation circuit 36 changed by electric switching valve 41 (B).

Embodiment 1 FIG.
FIG. 1 is a circuit configuration diagram of a hot water storage type hot water heater 1 according to Embodiment 1 of the present invention. A hot water storage type water heater 1 shown in FIG. 1 includes a heat pump unit 10 and a tank unit 20. The heat pump unit 10 is configured by sequentially connecting a compressor 11, a radiator 12, an expansion valve 13, and an evaporator 14 in an annular shape, and is housed in a housing 15. The heat pump unit 10 preferably uses carbon dioxide, which is a natural refrigerant, as a refrigerant, and operates on a high pressure side in a state exceeding the critical pressure.

  The tank unit 20 includes a hot water storage tank 22 for storing hot water supplied to the bathtub 2 in the housing 21. Further, the tank unit 20 includes a hot water storage circuit 23 for boiling water in the hot water storage tank 22 by using the heat pump unit 10 as a heating means. Specifically, the hot water storage circuit 23 includes a water outlet 22 a at the lower part of the hot water storage tank 22, a first heat pump pipe 24 that connects the radiator 12, and a water inlet 22 b at the upper part of the radiator 12 and the hot water storage tank 22. The 2nd heat pump piping 25 which connects to is provided. The hot water storage circuit 23 is provided with a hot water supply water pump 26 in the middle of the first heat pump pipe 24.

  A water supply pipe 27 for supplying water from a water supply source (not shown) is connected to the water outlet 22a. A water supply valve 28 is provided in the middle of the water supply pipe 27. The water supply valve 28 is configured to be opened when the high-temperature water in the hot water storage tank 22 is used for hot water supply, whereby water is supplied into the hot water storage tank 22 through the water outlet port 22a. Is done. Furthermore, a hot water supply port 29 is provided in the upper part of the hot water storage tank 22, and hot water stored in the hot water storage tank 22 is supplied to the bathtub 2 and other hot water taps (not shown). A hot water supply pipe 30 is connected. Here, detailed description and illustration of the hot water supply circuit are omitted.

  The tank unit 20 includes a tank hot water circulation circuit 31 that connects an upper part of the hot water storage tank 22 and a lower part of the hot water storage tank 22 in the housing 21. Furthermore, a reheating heat exchanger 32 is accommodated in the housing 21. The heat exchanger 32 is a plate heat exchanger in which a plurality of heat transfer plates are stacked. Here, such a plate heat exchanger is used vertically. The heat exchanger 32 is a water-water heat exchanger configured such that a fluid (water) flowing into the inside from two directions flows oppositely, and includes a first water inlet 32a and a second water inlet 32b. And a first water outlet 32c and a second water outlet 32d.

  The tank hot water circulation circuit 31 includes a first recirculation pipe 33 that connects the water outlet 22 c in the upper part of the hot water storage tank 22 and the first water inlet 32 a of the heat exchanger 32, and the first water guide of the heat exchanger 32. A second recirculation pipe 34 that connects the outlet 32 c and the water introduction port 22 d at the lower part of the hot water storage tank 22 is provided. The tank hot water circulation circuit 31 is provided with a tank hot water supply pump 35 in the middle of the second reheating pipe 34.

  The hot water storage type water heater 1 further includes a bathtub water circulation circuit 36 for circulating the bathtub water in the bathtub 2. More specifically, the bath return pipe 37 that connects the bathtub 2 and the second water inlet 32b of the heat exchanger 32, and the bath return that connects the second water outlet 32d of the heat exchanger 32 and the bathtub 2. And a pipe 38. The bathtub water circulation circuit 36 is provided with a water pump 39 and a bathtub water detection sensor 40 for detecting the presence of bathtub water in the bathtub 2 in the middle of the bath outlet pipe 37.

  Furthermore, the housing 21 of the tank unit 20 accommodates an electric switching valve (four-way valve) 41 for switching the flow path form of the bathtub water flowing in the bathtub water circulation circuit 36. More specifically, the electric switching valve 41 is interposed between a part on the second water introduction port 32 b side of the water supply pump 39 in the bath outlet pipe 37 and a part in the middle of the bath return pipe 38. .

  The electric switching valve 41 has a first flow path configuration in which bathtub water flows from the second water introduction port 32b side to the second water discharge port 32d side in the heat exchanger 32, and is opposite to the first flow channel configuration. Means for switching the second flow path form in which the bath water flows from the second water outlet 32d side toward the second water inlet 32b side.

  The hot water supply system including the hot water storage type hot water heater 1 shown in FIG. 1 includes a control unit 42 that comprehensively controls the hot water storage type hot water heater 1. Various sensors such as the bathtub water detection sensor 40 described above are electrically connected to the input of the control unit 42. In addition, various actuators such as the heat pump unit 10, the water pump 39, and the electric switching valve 41 described above are electrically connected to the output of the control unit 42. The control unit 42 is electrically connected to an operation unit (remote control device) 43 for a user using the bathtub 2 to remotely operate the hot water storage type hot water heater 1.

  Next, operation | movement of the hot water storage type water heater 1 of this embodiment provided with the structure demonstrated above is demonstrated.

  First, when the water in the hot water storage tank 22 is boiled, the operation of the heat pump unit 10 is executed. Thereby, the refrigerant in the refrigerant circuit is compressed by the compressor 11 to be high temperature and high pressure, and then cooled by the radiator 12. Thereafter, the refrigerant is decompressed by the expansion valve 13, absorbs heat from the atmosphere by the evaporator 14, evaporates, and returns to the compressor 11. On the other hand, water is supplied to the radiator 12 from the water outlet 22 a at the lower part of the hot water storage tank 22 by the hot water supply pump 26. The supplied water is heated by the radiator 12 and becomes high temperature, and then flows into the upper portion of the hot water storage tank 22 from the water inlet 22b. The hot water (hereinafter referred to as “tank hot water”) in the hot water storage tank 22 that has been boiled in this manner is sequentially supplied through the hot water supply pipe 30.

  Next, with reference to FIG. 2, the reheating operation and the backwashing operation performed immediately after the reheating operation will be described. FIG. 2 is a view for explaining two flow path configurations of the bathtub water circulation circuit 36 switched by the electric switching valve 41, and FIG. 2 (A) is a normal reheating path (the first flow channel configuration). FIG. 2 (B) shows the backflow cleaning path (the second flow path configuration).

  When the reheating operation is performed, the normal reheating route (first flow path configuration) shown in FIG. 2A is selected. And in order to make the tank hot water in the hot water storage tank 22 circulate through the tank hot water circulation circuit 31, the tank hot water use water supply pump 35 is driven, and the bathtub water in the bathtub 2 circulates in the bathtub water circulation circuit 36. In order to do so, the water pump 39 is driven.

  By performing the reheating operation, the bath water that has flowed out of the bathtub 2 through the bath outlet pipe 37 flows into the heat exchanger 32 from the second water inlet 32b. At this time, the bath water flowing into the heat exchanger 32 is heated by heat exchange with the tank hot water flowing in the tank hot water circulation circuit 31 and then returned to the bathtub 2 through the bath return pipe 38. It is. Thereby, bath water can be reheated.

  When the reheating operation is performed, in the tank hot water circulation circuit 31, high-temperature tank hot water existing above the hot water storage tank 22 flows out from the water outlet 22 c and passes through the first reheating pipe 33. It flows into the heat exchanger 32 from the first water inlet 32a. The tank hot water that has flowed into the heat exchanger 32 is cooled by heat exchange with the bathtub water flowing in the bathtub water circulation circuit 36, and then stored in the hot water storage port 22d through the second reheating pipe 34. It is returned to the lower part of the tank 22. According to such a chasing operation, compared with the case where the cold bathtub water in the bathtub 2 is once discharged and heated again, the amount of tank hot water used for hot water supply is small, and the hot water storage tank 22 Little water needs to be supplied from the bottom. Furthermore, in the present embodiment, a plate heat exchanger having a high heat exchange capability is used as the heat exchanger 32. For this reason, even when the reheating operation is performed in a state where a considerable amount of heat is accumulated in the hot water storage tank 22, it is possible to sufficiently perform heat exchange to keep the lower portion of the hot water storage tank 22 at a low temperature. On the other hand, even when the total amount of heat accumulated in the hot water storage tank 22 is relatively small, it is possible to reheat the bath water at a low temperature (for example, 10 ° C.) and heat it to a hot water temperature capable of bathing. It is. In addition, since the heat exchange capability is high, it is possible to realize a heat exchanger having a constant capability in a small size, and to realize space saving.

  Next, the backwashing operation in this embodiment will be described. This back-flow cleaning operation is performed by rotating the electric switching valve 41 90 degrees to the right from the state shown in FIG. 2A when the time periodically set in the control unit 42 is reached. This is executed by driving the water pump 39 in a state where the backflow cleaning path shown in FIG.

  When the water pump 39 is driven in a state where the backwashing path (second flow path configuration) shown in FIG. 2B is selected, the bath water discharged from the bathtub 2 through the bath outlet pipe 37 is electrically driven. After being guided to the bath return pipe 38 before entering the heat exchanger 32 by the type switching valve 41, it flows into the heat exchanger 32 from the second water outlet 32d side. Then, the bathtub water that has flowed into the heat exchanger 32 flows out from the second water introduction port 32 b to the bath outlet pipe 37, is then led to the bath return pipe 38 by the electric switching valve 41, and then returned to the bathtub 2. . Thus, when the backflow cleaning route is selected, the direction of the bath water flowing into the heat exchanger 32 is opposite to that when the normal reheating route is selected.

  Whether the bathtub water is present in the bathtub 2 is always detected by the bathtub water detection sensor 40, and the backflow cleaning operation is executed only when the bathtub water is present in the bathtub 2. More specifically, the above-mentioned regularly set time, which is the timing for performing the backwashing operation, is more specifically, for example, every day or every few days, and immediately after the reheating operation of the bath water is performed. Is preferable.

  As described above, the hot water storage type water heater 1 of the present embodiment includes the electric switching valve 41 that can switch the flow path of the bathtub water circulation circuit 36 between the normal reheating path and the backflow cleaning path. ing. Then, by selecting a backwashing path at a regularly set time and flowing bath water in a direction opposite to that in the reheating operation to the heat exchanger 32, the heat in the heat exchanger 32 is replenished in the reheating operation. Garbage such as hair accumulated in the passage on the inlet side (second water inlet 32b side) can be removed outside the heat exchanger 32. Thereby, the inside of the heat exchanger 32 can be kept clean.

  In the present embodiment, the timing for performing the backwash operation is set at a relatively short period of time such as every day or every few days and immediately after the chasing operation is performed. If the backwashing operation is executed at such a timing, hot water always exists in the bathtub 2 immediately after the reheating operation while the amount of dust caught on the heat exchanger 32 is very small. Therefore, it is possible to carry out backwashing at a timing at which an operational opportunity can be ensured. In addition, since the amount of dust is small at such timing, it can be said that there is no problem if the bathtub water after backwashing is returned to the bathtub 2 from the volume of the bathtub 2 as a whole.

  By the way, in Embodiment 1 mentioned above, when the said backflow washing | cleaning path | route is selected, the bathtub water after wash | cleaning the heat exchanger 32 is returned to the bathtub 2 through the bath return piping 38. FIG. However, the 2nd flow path form used as the object of the present invention is not limited to the above-mentioned backwashing course. That is, for example, in the housing 21, in the middle of the pipe 37 or 38 between the bathtub water outlet (second water inlet 32 b in FIGS. 1 and 2) of the heat exchanger 32 and the bathtub 2 during backflow cleaning. A discharge flow path for discharging bathtub water to the outside and a switching valve that can be switched to flow bathtub water through the discharge flow path are provided. The bath water after the backflow cleaning is discharged to the outside of the hot water storage hot water heater 1 through the discharge channel at the time of the backflow cleaning, and the bathtub water after the backflow cleaning is not discharged to the bathtub 2. Good. In addition, a backflow cleaning mode performed using such a drainage flow path is set in advance, and is executed when a command for executing such a backflow cleaning mode is issued by the operation unit (remote control device) 43. It may be.

  The hot water storage type hot water heater 1 using the heat pump according to the present invention is useful as a hot water heater with a bath replenishment function for supplying hot water to a bathtub 2 in a general household, and can provide a device with little influence of foreign matters.

DESCRIPTION OF SYMBOLS 1 Hot water storage type water heater 2 Bathtub 10 Heat pump unit 20 Tank unit 21 Housing 22 Hot water storage tank 31 Tank hot water circulation circuit 32 Heat exchanger 32a The 1st water inlet 32b of the heat exchanger 32 The 2nd water inlet 32c of the heat exchanger 32 The first water outlet 32d of the heat exchanger 32 The second water outlet 33 of the heat exchanger 32 The first reheating pipe 34 The second reheating pipe 35 The tank hot water supply pump 36 The bath water circulation circuit 37 The bath return pipe 38 The bath return Pipe 39 Water supply pump 40 Bath water detection sensor 41 Electric switching valve 42 Control unit 43 Operation unit (remote control device)

Claims (4)

A hot water storage tank for storing hot water supplied to the bathtub,
A tank hot water circulation circuit that connects between an upper part of the hot water storage tank and a lower part of the hot water storage tank, and circulates the hot water from the upper part of the hot water storage tank to the lower part of the hot water storage tank;
A bathtub water circulation circuit having a bathtub water circulation circuit connected to the bathtub, and circulating the bathtub water in the bathtub;
A heat exchanger for exchanging heat between the bathtub water flowing in the bathtub water circulation circuit and the tank hot water flowing in the tank hot water circulation circuit;
As the flow path form of the bathtub water flowing through the bathtub water circulation circuit, the first flow path form in which the bathtub water flows from the bathtub water side first inlet / outlet side to the bathtub water side second inlet / outlet side in the heat exchanger, Contrary to the 1 flow path form, the flow path switching means for switching the second flow path form in which the bath water flows from the bathtub water side second entrance / exit side toward the bath water side first entrance / exit side,
A hot water storage type water heater characterized by comprising: A bathtub water determination means for determining whether there is bathtub water in the bathtub,
The hot water storage system according to claim 1, wherein the flow path is switched from the first flow path configuration to the second flow path configuration only when it is determined that there is bathtub water in the bathtub. Water heater.   The flow from the first flow path configuration to the second flow path configuration immediately after the bath water replenishment operation is performed by flowing the bathtub water to the bathtub water circulation circuit in a state where the first flow channel configuration is selected. The hot water storage type hot water supply device according to claim 2, wherein the path is switched. The flow path switching means is an electric switching valve that switches between the first flow path form and the second flow path form,
The hot water storage type hot water supply apparatus according to claim 1 or 2, wherein the switching valve is installed in a tank unit that houses the hot water storage tank.

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