JP2012107843A - Water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water heater which can be continuously used even if high-hardness water is used as supply water.SOLUTION: The water heater includes: a tank 10 for storing a heating medium; a heating means 3 for heating the heating medium; a heating circuit 40 for hot water supply which takes out the heating medium of the tank 10 and returns the heating medium to the tank 10; a heat exchanger 50 for hot water supply which is disposed on the heating circuit for hot water supply, performs the heat-exchange of supply water with the heating medium and heats the supply water to produce supply hot water; a water supply circuit 21 for supplying the supply water to the heating circuit 40 for hot water supply; hot water supply circuits 20(30) for supplying the supply hot water heated by the heat exchanger 50 for hot water supply to hot water supply terminals A(B); and a heating medium introducing circuit 80 which is branched from the water supply circuit 21 and introduces the supply water into the tank 10 as the heating medium. The heat exchanger 50 for hot water supply is connected by joints F(51a, 51b, 51c, 51d) to pipes 41, 42 of the heating circuit for hot water supply, the pipe 21 of the water supply circuit and pipes 22(31) of pre-hot water supply circuit so as to be detachable.

Description

  The present invention relates to a water heater.

  Conventionally, as a hot water storage tank type water heater, a heating means for heating water (for example, a heat pump unit, an electric heater) and a tank for storing hot water heated by the heating means, using the hot water in the tank, Various hot water heaters that perform hot water supply, bathing, and heating have been proposed (see, for example, Patent Document 1 and Patent Document 2).

  By the way, in the conventional water heaters as described above, there are those that use hot water in the tank for general hot water supply or bathtub hot water supply. In such a water heater, the hot water discharged from the tank is newly supplied from the water supply source. Since the tank is replenished, a large amount of water is replaced in the tank every day. By the way, when the component of the water supply is high in hardness, the hardness component flows into the tank every time when the hot water is supplied or the hot water is supplied to the bathtub.

This hardness component, such as calcium and magnesium, is deposited as a scale (calculated from water in the form of solids by heating) when boiling the feed water flowing into the tank. Therefore, the flow path is clogged due to deposition on the water refrigerant heat exchanger (condenser) in the heat pump unit, and the heater efficiency is reduced due to deposition from the electric water heater around the heater. For those using hot water, it was impossible to use high-hardness water. In addition, hot water in the tank is not used for general hot water supply or bathtub hot water supply, but the hot water in the tank is used as a heat medium to heat (exchange heat) the secondary water supply and use it for general hot water supply or bathtub hot water supply Have been proposed (for example, Patent Documents 3 to 8).
In such a water heater, since no new water is supplied into the tank at the time of general hot water supply or bath water supply, even if the water supply component has high hardness, it can be reduced that the hardness component flows into the tank. .

JP 2006-329581 A JP 2008-45851 A Japanese Patent No. 4064356 Japanese Patent No. 4101190 JP 2005-207672 A JP 2006-300489 A JP 2006-336937 A JP 2009-150635 A

Instead of directly using the hot water in the tank for general hot water supply or bathtub hot water supply, the hot water in the tank is used as the primary (heating side) heating medium, and the secondary side (heated side) water supply is heated to provide general hot water supply. A hot water heater used for a hot water supply for a bathtub and a bathtub (see Patent Documents 3 to 8) includes a heat exchanger for hot water supply for heating the water supply by exchanging heat with the heat medium (hot water in the tank).
Water supply from a water supply source flows into the secondary side of the heat exchanger for hot water supply during general hot water supply or bath water supply. At this time, if the water supply component has high hardness, the hardness component (calcium, magnesium, etc.) flows into the secondary side of the hot water supply heat exchanger every time hot water is supplied to the hot water or bath water, and scale is deposited in the high temperature area. There is a risk of clogging the flow path.

  Then, this invention makes it a subject to provide the water heater which can be continuously used even if it uses high hardness water as water supply.

  In order to solve such a problem, the invention according to claim 1 includes a tank for storing a heat medium, a heating unit for heating the heat medium stored in the tank, and the heat stored in the tank. A hot water supply heating circuit that takes out the medium and returns it to the tank, a hot water supply heating circuit that is provided in the hot water supply heating circuit, heats the supplied water by heat exchange with the heat medium and heats the hot water supply, and the hot water supply heating circuit A hot water supply circuit for supplying the hot water to the hot water supply terminal, a hot water supply circuit for supplying the hot water heated by the hot water heat exchanger to the hot water supply terminal, and branching from the hot water supply circuit to supply the hot water to the tank as the heat medium. The hot water supply heat exchanger is connected to a pipe of the hot water supply heating circuit, a pipe of the water supply circuit, and a pipe of the hot water supply circuit by a detachable joint. It is characterized by .

  According to the present invention, when the heat exchanger for hot water supply can be easily replaced, and the scale is deposited on the secondary side (heated side) of the heat exchanger for hot water supply, the flow path is clogged. By regularly exchanging, it is possible to provide a water heater that can be used continuously even when high-hardness water is used as water supply.

It is a whole circuit diagram of the water heater based on this embodiment. The hot water supply heat exchanger is shown alone, (a) is a perspective view, and (b) is a side view. It is sectional drawing which shows the state which connected the hot water supply heat exchanger and piping using the quick fastener. The quick fastener simple substance is shown, (a) is a perspective view, (b) is a side view, and (c) is a front view. It is a flowchart figure explaining the removal procedure of a hot water supply heat exchanger. It is a flowchart figure explaining the attachment procedure of a hot water supply heat exchanger.

≪Water heater≫
Hereinafter, the water heater 1 of this embodiment is demonstrated with reference to drawings.
As shown in FIG. 1, the water heater 1 of the present embodiment includes a heat storage tank unit 2 and a heat pump unit (heating means) 3.

  The heat storage tank unit 2 includes a heat storage tank 10, a general hot water supply circuit 20, a bathtub hot water supply circuit 30, a hot water supply heating circuit 40, a hot water supply heat exchanger (hot water supply heat exchanger) 50, a bathtub water circulation circuit 60, a reheating heat exchanger ( (Bath heat exchanger) 70, heat medium introduction circuit 80, relief valve 90, controller 100, and the like.

  Although not shown, for example, the heat pump unit 3 compresses a refrigerant (for example, carbon dioxide) to a high temperature and a high pressure, condenses the refrigerant from the compressor, and exchanges heat from water from the heat storage tank 10. A condenser (water refrigerant heat exchanger) that heats by this, an expansion valve that expands the refrigerant from the condenser, and an evaporator that absorbs heat in the atmosphere and evaporates the expanded refrigerant are configured.

  The heat pump unit 3 has a heat medium inlet connected to the lower part of the heat storage tank 10 via the heat pump forward pipe 4, and a heat medium outlet connected to the upper part of the heat storage tank 10 via the heat pump return pipe 5. Although not shown, for example, on the heat pump unit 3 side, a circulation pump that circulates the heat medium in the heat storage tank 10 between the heat storage tank 10 and the heat pump unit 3 is provided.

  Further, a heat pump return pipe 5 is connected in the middle of the heat pump forward pipe 4 via a pipe 6, and a three-way valve 7 is provided at a connection portion between the heat pump forward pipe 4 and the pipe 6. When the controller 100 determines that the heat pump forward pipe 4 and the heat pump return pipe 5 located outside the heat storage tank unit 2 may be frozen, the three-way valve 7 is switched and the heat pump unit 3 and the circulation pump (not shown) are switched. The refrigerant warmed by the heat pump unit 3 is circulated so as to flow through the heat pump return pipe 5, the pipe 6, and the heat pump forward pipe 4. Thereby, freezing of piping exposed to the outside air outside the heat storage tank unit 2 can be prevented.

  Note that the heat pump unit 3 has been described as an example of the heat source unit for heating the hot water in the heat storage tank 10, but the heat pump unit 3 is not limited thereto, and may be an electric heater, for example.

  The heat storage tank 10 is a sealed tank that stores hot water as a heat medium, and has a vertically long cylindrical shape. Further, the heat storage tank 10 is covered with a heat insulating material such as foamed polystyrene in order to improve heat retention performance.

  The heat storage tank 10 is provided with a plurality of tank temperature sensors 11 to 15 that detect the temperature of the heat medium (hot water) at different height positions. Specifically, the tank 10 is provided with five tank temperature sensors 11 to 15 from the upper part to the lower part. Thereby, the controller 100 can grasp the temperature distribution of the hot water in the heat storage tank 10.

  The general hot water supply circuit 20 is a flow path for supplying hot water to the general hot water supply terminal A, and includes a water supply pipe (water supply circuit) 21 and a hot water supply pipe 22.

  The water supply pipe 21 has an upstream end connected to a water supply source and a downstream end connected to a secondary water supply inlet 51a of a hot water supply heat exchanger 50 described later.

  In addition, as a water supply source to which the water supply pipe 21 is connected, it is not limited to a water supply, Well water (ground water), a hot spring, a river, etc. can be mentioned. As for the water supply source, the type of water supply when using tap water is tap water, the type of water supply when using groundwater is well water (groundwater), and the type of water supply when using hot springs is hot spring water ( The type of water supply when using a river is river water. In particular, the water heater 1 according to the present embodiment is not only applied to tap water (soft water) having a small hardness component, but can also be applied to tap water and well water (high hardness water) containing a large amount of hardness component. It is possible. That is, the water heater 1 according to the present embodiment can cope with a wide variety of water supplies regardless of whether the water is soft water or high hardness water.

  The hot water supply pipe 22 has an upstream end connected to a secondary hot water outlet 51 b of the hot water heat exchanger 50 and a downstream end connected to various general hot water terminals A. The hot water supply pipe 22 is provided with a flow rate sensor 23 and an accumulator 24 in order from the upstream side. The general hot water supply terminal A is a faucet or shower in a kitchen, a washroom, a bathroom, etc., and means a usage form in which the supplied hot water is used once and completed.

  The flow rate sensor 23 detects the flow rate of hot water flowing through the hot water supply pipe 22 (flow rate of hot water supplied to the general hot water supply terminal A), and the rotation of the motor of the hot water supply circulation pump 44 described later in accordance with the detected flow rate. Adjust the speed. For example, if the hot water supply temperature is set to 40 ° C., hot water is supplied by adjusting the rotational speed of the hot water circulation pump 44 so that the hot water supply temperature is 40 ° C.

  The accumulator 24 has a function as a buffer for discharging hot water after it has been discharged from a faucet or a shower (after the temperature of the hot water has been lowered).

  The water supply pipe 21 is provided with a water supply temperature sensor 25 upstream of the hot water supply heat exchanger 50, and the hot water supply pipe 22 is provided with a hot water supply temperature sensor 26. The feed water temperature sensor 25 detects the temperature of the feed water before being introduced into the hot water supply heat exchanger 50. The hot water temperature sensor 26 detects the temperature of the hot water discharged from the hot water heat exchanger 50.

  The water supply pipe 21 is provided with a water supply tap 99 upstream of the branch P1 and a water supply drain plug 97 on the downstream side of the water supply tap 99 and on the upstream side of the hot water supply heat exchanger 50. The hot water supply pipe 22 is provided with a hot water drain plug 98 on the downstream side of the accumulator 24.

  The water supply drain plug 97 is manually opened and closed, for example, and is opened when the hot water supply heat exchanger 50 described later is replaced, so that the secondary side of the general hot water supply circuit 20 (water supply pipe 21) and the hot water supply heat exchanger 50 is opened. Inside water (water supply) can be extracted to the outside. For this reason, it is preferable that the feed water drain plug 97 is provided at a position lower than the feed water inlet 51a on the secondary side of the hot water heat exchanger 50 and can be drained by gravity.

  The hot water drain plug 98 is manually opened and closed, for example, and is opened when the hot water heat exchanger 50 to be described later is replaced, so that the general hot water supply circuit 20 (hot water supply pipe 22) and the bathtub hot water supply circuit 30 (bath pouring pipe). The hot water (hot water supply) in 31, 32) can be extracted to the outside. For this reason, the hot water drain plug 98 is preferably provided at a position lower than the hot water outlet 51b on the secondary side of the hot water heat exchanger 50 and can be drained by gravity.

  The water tap 99 is manually opened and closed, for example, and can be closed to stop water supply from the water supply source to the water heater 1. The water tap 99 may be provided in the heat storage tank unit 2 of the water heater 1, or may be a water tap provided in a water supply source that supplies water to the water heater 1.

  The bathtub hot water supply circuit 30 is a flow path for supplying hot water to the bathtub B, and includes a water supply pipe 21, bath pouring pipes 31 to 35, and a bath return pipe 61. The water supply pipe 21 of the bathtub hot water supply circuit 30 is a common pipe with the water supply pipe 21 of the general hot water supply circuit 20. Further, the bath pouring pipe 31 is a pipe shared with a part of the hot water supply pipe 22, and extends to the general hot water supply terminal A and the bathtub B through the branch portion S. The bath return pipe 61 is a common pipe for a bathtub water circulation circuit 60 described later.

  The bath pouring pipe 31 includes, in order from the upstream side, a flow rate adjusting valve 36, a bath pouring pipe 32, an electromagnetic valve 37, a bath pouring pipe 33, a bath circulation pump 38, a bath pouring pipe 34, a circulation regulating valve (flow rate). It is connected to the bathtub B through the adjustment valve 39 and the bath pouring pipe 35. The bath pouring pipe 33 is provided with a flow rate sensor 33a.

  The flow rate adjusting valve 36 adjusts the flow rate of hot water flowing through the bath pouring pipes 31 to 35. For example, in the case of using only hot water in a bathtub (only hot water filling) without using general hot water, the flow rate adjusting valve 36 is adjusted so that the flow rate becomes maximum. The flow rate adjustment valve 36 is adjusted so that the flow rate of the pouring pipes 31 to 35 is reduced or the flow rate is zero.

  The electromagnetic valve 37 is an electromagnetically operated shut-off valve and is controlled to be opened and closed by the controller 100. By closing the solenoid valve 37, the hot water supply to the bathtub B is shut off. The solenoid valve 37 has a backflow prevention function (such as a check valve) so that the bath water does not flow back to the general hot water supply circuit 20.

  The bath circulation pump 38 is driven in the reheating mode, and has a function of circulating the bath water stretched on the bathtub B with the reheating heat exchanger 70 described later.

  The circulation adjusting valve 39 can adjust the flow rate from the bath pouring pipe 34 to the bath pouring pipe 35 and the flow rate from the bath pouring pipe 34 to the reheating heat exchanger forward pipe 62 of the bathtub water circulation circuit 60 described later. This is a flow regulating valve having a function that can be performed.

  The flow rate sensor 33a detects the flow rate of hot water flowing through the bath pouring pipe 33 (flow rate of hot water supplied to the bathtub B), and the rotation of the motor of the hot water supply circulation pump 44 described later according to the detected flow rate. Adjust the speed.

  The hot water supply temperature sensor 26 is located on the upstream side of the branch section S, and is a shared temperature sensor that detects the hot water supply temperatures in the general hot water supply mode and the bathtub hot water supply mode.

  The hot water supply heating circuit 40 takes out the heat medium (hot water) stored in the heat storage tank 10 and returns it to the heat storage tank 10. The hot water supply heat exchanger forward pipe 41, the hot water supply heat exchanger return pipes 42 and 43, And a hot water supply circulation pump 44.

  The hot water supply heat exchanger forward pipe 41 is a flow path for supplying the heat medium (hot water) in the heat storage tank 10 to the hot water supply heat exchanger 50, the upstream end is connected to the upper part of the heat storage tank 10, and the downstream end is hot water supply heat. It is connected to the inlet 51c on the primary side of the exchanger 50.

  The hot water supply heat exchanger return pipe 42 has an upstream end connected to the outlet 51 d on the primary side of the hot water supply heat exchanger 50 and a downstream end connected to the inlet of the hot water supply circulation pump 44.

  The hot water supply heat exchanger return pipe 43 has an upstream end connected to the outlet (discharge port) of the hot water supply circulation pump 44 and a downstream end connected to the lower part of the heat storage tank 10. The hot water supply heat exchanger return pipe 43 is provided with a check valve 43 b for preventing a back flow of the hot water supply circulation pump 44.

  The hot water supply circulation pump 44 is driven by the controller 100 to take out the heat medium (hot water, high temperature water) from the upper part in the heat storage tank 10 and return it to the lower part of the heat storage tank 10 for circulation. .

  Further, the hot water circulation pump 44 changes the heat transfer rate to the secondary side water supply in the hot water supply heat exchanger 50 by controlling the rotation speed of a motor (not shown) by the controller 100, so that the hot water supply circulation pump 44 is in the general hot water supply mode. The hot water supply temperature and the hot water supply temperature in the bathtub hot water supply mode are adjusted. In other words, in this embodiment, the hot water supply (hot water) after heat exchange by the hot water supply heat exchanger 50 is not provided with a mixing valve that is mixed with the supply water to obtain a desired hot water supply temperature (hot water). The hot water discharged from the heat storage tank 10 is returned to the heat storage tank 10 in its entirety.

  The hot water supply heat exchanger return pipe 43 is provided with a pump air vent plug 43 a for extracting gas (air) of the hot water supply circulation pump 44. The hot water supply circulation pump 44 is provided with a pump drain plug 44a for extracting liquid (heat medium, hot water) in the hot water supply circulation pump 44 to the outside.

  The pump air vent plug 43a is, for example, manually opened and closed, and is opened when water is poured from a state in which the heat storage tank 10 is not full or when water is poured after the hot water supply heat exchanger 50 described later is attached. The air in the pump 44 (air) can be extracted to the outside together with water.

The pump drain plug 44a is manually opened and closed, for example, so that the liquid (heat medium, hot water) in the hot water supply circulation pump 44 can be extracted to the outside.
Moreover, the pump air vent plug 43a and the pump water drain plug 44a are also used when the hot water supply heat exchanger 50, which will be described later, is opened to extract the heat medium (hot water) of the hot water supply heating circuit 40 to the outside.

  The hot water supply heat exchanger 50 heats water by exchanging heat supplied from the water supply pipe 21 with a heat medium (hot water) taken out from the upper part of the heat storage tank 10. The generated hot water supply is used for general hot water supply via the hot water supply pipe 22, and is used for bath hot water supply via the bath pouring pipes 31 to 35 and the bath return pipe 61.

  The hot water supply heat exchanger 50 is configured to be detachable between the water supply pipe 21, the hot water supply pipe 22 (bath pouring pipe 31), the hot water supply heat exchanger forward pipe 41 and the hot water supply heat exchanger return pipe 42. . That is, if the hot water supply heat exchanger 50 needs to be replaced, only the hot water supply heat exchanger 50 can be removed from the heat storage tank unit 2. The attachment / detachment mechanism of the hot water supply heat exchanger 50 will be described later.

  Thus, in this embodiment, since the hot water supply heating circuit 40 is constituted by a closed circuit, the hot water in the heat storage tank 10 is not discharged to the general hot water supply terminal A and the bathtub B. In other words, the hot water (heat medium) in the heat storage tank 10 is used only as a heat medium for heating the secondary-side water supply during general hot water supply or bathtub hot water supply.

  The bathtub water circulation circuit 60 takes out the bathtub water stored in the bathtub B and returns it to the bathtub B. The bath return pipe 61, the bath pouring pipes 33 and 34, the reheating heat exchanger outgoing pipe 62, A bath outlet pipe 63 and a bath pouring pipe 35 are configured. Thus, the bathtub water circulation circuit 60 is a pipe shared with a part of the bathtub hot water supply circuit 30, that is, a part of the bath pouring pipe 33, a part of the bath pouring pipe 34, and a part of the bath pouring pipe 35.

  The bath return pipe 61 is a flow path for taking out bathtub water from the bathtub B, and has an upstream end connected to the bathtub B and a downstream end connected to the bath pouring pipe 33.

  The reheating heat exchanger forward pipe 62 has an upstream end connected to the circulation regulating valve 39 and a downstream end connected to the inlet of the reheating heat exchanger 70 to send the bath water to the reheating heat exchanger 70. It has become.

  The bath outlet pipe 63 has an upstream end connected to the outlet of the reheating heat exchanger 70, a downstream end connected to the middle of the bath pouring pipe 35, and bath water that has been heat-exchanged by the reheating heat exchanger 70. A flow path is provided to the bath pouring pipe 35.

  The bath return pipe 61 is provided with a water level sensor 64, a water flow switch 65, and a bath temperature sensor 66.

  The water level sensor 64 detects the water level of the bathtub water stored in the bathtub B. For example, when the controller 100 detects that a water level set in advance by the water level sensor 64 has been reached in the bathtub hot water supply mode, the hot water supply to the bathtub is stopped.

  The water flow switch 65 is a sensor that detects whether or not bathtub water is flowing in the chasing mode, and whether or not the bathtub water stored in the bathtub B is flowing through the bath return pipe 61 in the direction of the arrow (upper side in the drawing). Is detected.

  The bath temperature sensor 66 detects the temperature of the bathtub water in the bathtub hot water supply mode and the temperature of the bathtub water in the chasing mode.

  In addition, the bath outlet pipe 63 is provided with a reheating temperature sensor 67 that detects the temperature of the bath water after the heat is exchanged by the reheating heat exchanger 70.

  The reheating heat exchanger 70 is disposed in the upper part of the heat storage tank 10, and bath water (hot water or water) introduced from the reheating heat exchanger forward pipe 62 and a heat medium (hot water, high temperature) in the heat storage tank 10. The water is exchanged with the hot water and supplied to the bath outlet pipe 63.

  The heat medium introduction circuit 80 is composed of water supply tank containing pipes 81 and 82 and a pressure reducing valve 83, and constitutes a flow path for introducing water supply supplied from a water supply source into the heat storage tank 10. That is, the heat medium introduction circuit 80 is a heat medium replenishment circuit that performs replenishment when the heat medium in the heat storage tank 10 decreases with time.

  The water supply tank containing pipe 81 has an upstream end connected to the branch P <b> 1 in the middle of the water supply pipe 21 and a downstream end connected to the primary side of the pressure reducing valve 83.

  The water supply tank containing pipe 82 has an upstream end connected to the secondary side of the pressure reducing valve 83 and a downstream end connected to join the hot water supply heat exchanger return pipe 43. The water supply tank containing pipe 82 is provided with a check valve 82b for preventing a back flow from the heat storage tank 10 to the water supply pipe (water supply circuit) 21.

  The pressure reducing valve 83 protects the heat storage tank 10 by reducing the pressure of the water supply (primary pressure) to a predetermined pressure (secondary pressure). The predetermined pressure set in the pressure reducing valve 83 can be appropriately changed according to the strength of the heat storage tank 10.

The relief valve 90 is opened when a predetermined pressure not exceeding the pressure resistance of the heat storage tank 10 is reached, is not electrically controlled by the controller 100, and is mechanical when the predetermined pressure is reached. It is configured to open the valve. Therefore, the valve is automatically closed when the pressure in the heat storage tank 10 falls below a predetermined pressure after the valve is opened.
Further, the relief valve 90 can be manually opened when the heat medium (hot water) in the heat storage tank 10 and the hot water supply heating circuit 40 is extracted to the outside.

  The relief valve 90 is provided in the relief pipe 91. One end of the escape pipe 91 is connected so as to branch from the hot water supply heat exchanger forward pipe 41, and the other end is open to the atmosphere (outside air). Note that the relief valve 90 is not limited to a mechanically operated valve, and is provided with a pressure sensor that detects the pressure in the heat storage tank 10, and based on the detected value of the pressure sensor (the same pressure as described above is obtained). Sometimes, the relief valve 90 may be opened electrically. Further, the relief valve 90 is not limited to one that can be manually opened, and may be one that opens electrically based on a command from the controller 100.

  A discharge pipe 96 having a tank drain plug 95 is connected to the heat pump forward pipe 4 between the heat storage tank 10 and the three-way valve 7. The tank drain plug 95 is manually opened and closed, for example, and is opened when dirt accumulates in the heat storage tank 10 or when the water heater 1 is not used for a long period of time. The heat medium (hot water) can be extracted outside.

  The controller 100 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc., and the rotational speeds of the motors of the bath circulation pump 38 and the hot water supply circulation pump 44 and the three-way valve 7. The flow path switching, the flow rate of the flow rate adjustment valve 36 and the circulation adjustment valve 39, and the opening and closing of the electromagnetic valve 37 are controlled, the flow of bathtub water by the water flow switch 65, the water level of the bathtub water stored in the bathtub B by the water level sensor 64, The temperature by various temperature sensors 11-15, 25, 26, 66, 67 is acquired.

  Note that a bath remote controller or kitchen remote controller (not shown) is connected to the controller 100 by wire or wirelessly, and a hot water supply circulation pump 44, a bath circulation pump 38, and a three-way valve are operated in accordance with an operation of an operation unit provided in the bath remote controller or kitchen remote controller. 7. The flow rate adjustment valve 36, the electromagnetic valve 37, and the circulation adjustment valve 39 are appropriately controlled.

  Next, the boiling mode, the general hot water supply mode, the bathtub hot water supply mode, and the reheating mode in the water heater 1 of the present embodiment will be described with reference to FIG.

<Boiling mode>
In the case of the boiling mode, the heat medium (water) in the heat storage tank 10 is boiled by the heat pump unit 3. That is, a heat medium (water) is sent from the lower part of the heat storage tank 10 to the heat pump unit 3 through the heat pump forward pipe 4, and the heat medium (hot water) heated by the heat pump unit 3 is supplied to the heat storage tank through the heat pump return pipe 5. By returning to the upper part of 10, for example, low temperature water is stored in the lower part, intermediate temperature water is stored in the middle part, and high temperature water is stored in the upper part in the heat storage tank 10.

<General hot water supply mode>
In the case of the general hot water supply mode, the operation is started when the flow rate sensor 23 detects the flow in the general hot water supply circuit 20. At this time, the electromagnetic valve 37 is closed. That is, when the general hot water supply terminal A (such as a faucet) is opened by the control of the controller 100, the flow of the general hot water supply circuit 20 is detected by the flow rate sensor 23, and the hot water at the hot water temperature set in the operation unit of the kitchen remote controller is detected. Is supplied from the general hot water supply terminal A, the hot water supply circulation pump 44 is driven.

  More specifically, based on the feed water temperature detected by the feed water temperature sensor 25 and the flow rate detected by the flow sensor 23, the temperature of the motor of the hot water circulation pump 44 is adjusted so that the temperature detected by the hot water temperature sensor 26 becomes the target temperature. Adjust the rotation speed. At this time, the secondary side feed water is heated by heat exchange by the heat medium flowing through the primary side of the hot water supply heat exchanger 50. The hot water supply circulation pump 44 stops when the flow rate sensor 23 detects that the general hot water supply terminal A is closed.

  Note that the target temperature in hot water supply temperature sensor 26 is set higher than the set temperature in consideration of a temperature drop or the like until hot water reaches general hot water supply terminal A from hot water supply temperature sensor 26. However, the present invention is not limited to such control, and the target temperature may be the same as the set temperature.

  Thus, in this embodiment, since the temperature of the hot water supplied from the general hot water supply terminal A is adjusted by controlling the rotation speed of the motor of the hot water supply circulation pump 44, the hot water supply heat exchanger 50 is provided downstream. It is not essential to provide a mixing valve that mixes the hot water (hot water) generated by the hot water heat exchanger 50 and the hot water provided by bypassing the hot water heat exchanger 50 and supplies it from the general hot water terminal A. . However, a mixing valve may be provided for the purpose of adjusting the temperature of hot water with higher accuracy.

<Bath water supply mode>
In the bathtub hot water supply mode, for example, the operation is started by operating a hot water filling start operation switch provided in the operation unit of the bath remote controller. At this time, the solenoid valve 37 is opened and the circulation adjusting valve 39 is set so that the bath pouring pipe 34 and the bath pouring pipe 35 communicate with each other. The flow rate adjusting valve 36 is controlled so that the opening degree is small at the initial stage of operation and gradually increases.

  When the operation is started, the hot water supply circulation pump 44 is driven so that hot water having a set hot water temperature is supplied to the bathtub B. More specifically, the hot water supply circulation pump 44 is controlled based on the feed water temperature detected by the feed water temperature sensor 25 and the flow rate detected by the flow rate sensor 33a so that the temperature detected by the hot water supply temperature sensor 26 becomes the target temperature. To do.

  Thus, hot water generated from the water supply pipe 21 via the hot water supply heat exchanger 50 is supplied mainly to the bath B through the bath pouring pipes 31 to 33 and the bath return pipe 61, and a part of the bath It is supplied to the bathtub B through the hot water pipes 33 to 35. Thus, in the bathtub hot water supply mode, hot water flows through the bath return pipe 61 in the reverse direction. Then, when the water level sensor 64 detects that a predetermined amount of hot water has been stored in the bathtub B, the hot water supply circulation pump 44 is stopped and hot water filling is completed.

  In addition to hot water filling, the bathtub hot water supply mode is from a water supply source such as additional hot water that adds hot water equivalent to the set temperature, hot water that adds hot water higher than the set temperature to raise the temperature of bathtub B, etc. Various hot water supply modes in which the hot water is heated and supplied to the bathtub B are also included. In addition to this, there is a hot water supply mode in which water is supplied to the bathtub B without being heated by the hot water supply heat exchanger 50.

  Further, when the general hot water supply terminal A is opened in the bathtub hot water supply mode, the flow rate adjustment valve 36 of the bathtub hot water supply circuit 30 is throttled (controlled in the closing direction). Thereby, about the hot water supply produced | generated with the hot water supply heat exchanger 50, the flow volume supplied to the bathtub hot-water supply circuit 30 reduces, and hot water supply to the general hot-water supply circuit 20 is started. Thus, when both general hot water supply and bathtub hot water supply are necessary at the same time, priority is given to general hot water supply terminal A, that is, priority is given to general hot water supply terminal A, and the hot water filling of bathtub B is narrowed down. Is preferred. In such a case, the flow rate adjustment valve 36 may be fully closed to completely stop the flow rate of hot water to the bathtub hot water supply circuit 30. Further, as a method for completely stopping the flow rate of hot water to the bathtub hot water supply circuit 30, the electromagnetic valve 37 may be closed.

  As described above, the hot water supply capacity of the water heater 1 (the capacity of the heat storage tank 10, the hot water pressure, the hot water supply heat exchange) is adjusted for the hot water supply of the bathtub when the hot water supply request is made from the general hot water supply terminal A in the bathtub hot water supply mode. The heat exchange capacity of the vessel 50 can be changed as appropriate. For example, in the case of a water heater having a low hot water supply capacity, the hot water supply to the bathtub can be stopped until the hot water supply request from the general hot water supply terminal A stops.

<Remembrance mode>
In the case of the chasing mode, for example, the operation is started by operating a chasing switch provided in the operation unit of the bath remote controller. First, in a state where the electromagnetic valve 37 is closed, the opening degree of the circulation adjusting valve 39 is set so as to be fully opened from the bath pouring pipe 34 to the bath pouring pipe 35 side, and the bath circulation pump 38 is driven. Thereby, the bathtub water stored in the bathtub B circulates through the bath return pipe 61 and the bath pouring pipes 33, 34, and 35.

  Then, the circulation control valve 39 is controlled to gradually open toward the reheating heat exchanger forward pipe 62, and the bath temperature sensor is set so that the temperature in the bath pouring pipe 35 becomes a predetermined temperature (for example, 60 ° C.). 66 and the opening degree of the circulation regulating valve 39 is controlled while predicting from the temperature detected by the tracking temperature sensor 67. When the temperature detected by the bath temperature sensor 66 (the temperature of the bath water) reaches the set temperature, the bath circulation pump 38 is stopped and the reheating mode is ended.

  In the bathtub hot water supply mode and the reheating mode, as in the general hot water supply mode, the difference between the temperature detected by the reheating temperature sensor 67 and the temperature of the bathtub water in the bathtub B is taken into consideration. Set high. However, the present invention is not limited to this, and the target temperature may be the same as the set temperature.

  Further, when the general hot water supply terminal A is opened during the reheating mode, the temperature of the hot water supply temperature sensor 26 is determined based on the temperature of the water supply temperature sensor 25 and the flow rate of the flow sensor 23 as in the control of the general hot water supply mode. The hot water supply circulation pump 44 is controlled so that becomes the target temperature.

  By the way, in the boiling mode, the pressure in the heat storage tank 10 increases as the temperature of the water in the heat storage tank 10 increases. The relief valve 90 provided in the upper part of the heat storage tank 10 is a relief valve when the pressure of the heat storage tank 10 approaches the pressure exceeding the pressure resistance (when the pressure is set in advance so as not to exceed the pressure resistance of the heat storage tank 10). 90 opens automatically. Thereby, the heat medium (hot water for volume expansion) in the heat storage tank 10 is discharged outside.

  Further, in the general hot water supply mode and the bath hot water supply mode, the heat medium (high temperature water) is circulated by the hot water supply circulation pump 44, and heat is exchanged with the secondary side water supply in the hot water supply heat exchanger 50 to heat the secondary side water supply. It is used for general hot water supply and bathtub hot water supply. At this time, since the heat medium (water) returning from the hot water supply heat exchanger 50 through the hot water supply heat exchanger return pipes 42 and 43 to the heat storage tank 10 has substantially the same temperature as the water supply, the temperature in the heat storage tank 10 And the pressure drops. In this way, when the pressure in the heat storage tank 10 is lowered, the same amount of water as the heat medium discharged from the relief valve 90 (the water supply corresponding to the volume expansion) is replenished from the water supply tank containing pipes 81 and 82. It will be. Therefore, the heat medium for the amount discharged from the relief valve 90 is automatically supplied into the heat storage tank 10.

≪Replacement of hot water heat exchanger≫
By the way, in the general hot water supply mode and the bathtub hot water supply mode, the water supply from the water supply source flows into the secondary side of the hot water supply heat exchanger 50 (the flow path from the inlet 51a to the outlet 51b). At this time, when the component of the water supply is high in hardness, the hardness component (calcium, magnesium, etc.) flows into the secondary side of the hot water supply heat exchanger 50 every time in the general hot water supply mode or the bathtub hot water supply mode, and the hot water supply heat exchanger 50 There is a possibility that the scale deposits in the high temperature part (near the secondary side outlet side in the hot water supply heat exchanger 50) and the flow path is clogged. For this reason, the hot water heater 1 according to the present embodiment is configured such that the hot water supply heat exchanger 50 is detachable.

<Configuration of hot water heat exchanger>
First, the structure of the hot water supply heat exchanger 50 will be described. FIG. 2 shows a single hot water supply heat exchanger 50, (a) is a perspective view, and (b) is a side view.
As shown in FIG. 2 (a), the hot water supply heat exchanger 50 is a plate heat exchanger in which a plurality of heat transfer plates are stacked, and includes a secondary side inlet 51a, a secondary side outlet 51b, It has a primary-side inlet 51c and a primary-side outlet 51d.
Inside the hot water supply heat exchanger 50, a flow path is formed between the heat transfer plates, a secondary flow path communicating from the inlet 51a to the outlet 51b is formed, and a primary communicating from the inlet 51c to the outlet 51d. A side flow path is formed. The fluid flowing in the primary channel (heat medium from the heat storage tank 10) and the fluid flowing in the secondary channel (water supply supplied from the water supply source) can exchange heat via the heat transfer plate. It is configured.

  And, as shown in FIG. 2 (a), the hot water supply heat exchanger 50 has an odd number of passes, and a secondary side outlet 51b and a primary side inlet 51c are arranged on the upper side of the one surface side, A secondary-side inlet 51a and a primary-side outlet 51d are arranged in the lower part on the other surface side. Note that the pass represents the number of fluid folds, and the case of no wrapping is expressed as one pass, and one reciprocation (the number of folds is one) is expressed as two passes. The number of passes increases by one.

  Temporarily, in the case of a hot water supply heat exchanger having an even number of passes, a secondary-side outlet 51b and a primary-side inlet 51c are arranged at the lower part on one side, and a secondary-side inlet 51a and a primary are provided at the upper side on the other side. The side outlet 51d is arranged. In this case, the pipes connected to each inlet and outlet sandwich the even-numbered hot water supply heat exchanger from both sides, making it difficult to remove and attach the hot water heat exchanger.

On the other hand, as shown in FIG. 2B, the hot water supply heat exchanger 50 has a secondary-side outlet 51b and a primary-side inlet 51c arranged at the upper part on one side, and an inlet at the upper part on the other side. / Joint F (see FIG. 3) serving as an outlet is not arranged. Similarly, a secondary-side inlet 51a and a primary-side outlet 51d are disposed in the lower part on the other surface side, and a joint F (see FIG. 3) serving as an inlet / outlet is not disposed in the lower part on the one-surface side.
For this reason, as shown in FIG. 2 (b), the hot water supply heat exchanger 50 can be removed from the pipe by rotating the hot water supply heat exchanger 50 counterclockwise as viewed from the side. The vessel 50 can be connected to the pipe so as to rotate clockwise.

The hot water supply heat exchanger 50 is desirably compact and lightweight. Further, it may be supported only by connected pipes (water supply pipe 21, hot water supply pipe 22 (bath pouring pipe 31), hot water supply heat exchanger forward pipe 41 and hot water supply heat exchanger return pipe 42), It may be placed on a support base (not shown).
The pipes connected to the hot water supply heat exchanger 50 (the water supply pipe 21, the hot water supply pipe 22 (bath pouring pipe 31), the hot water supply heat exchanger forward pipe 41 and the hot water supply heat exchanger return pipe 42) are stainless steel pipes. It is desirable. The stainless steel pipe is not easily bent, and the posture of the hot water supply heat exchanger 50 is easily determined at the time of replacement work. Therefore, the replacement work becomes easy.

<Hot-water heat exchanger attachment / detachment mechanism>
Next, a mechanism for attaching and detaching hot water supply heat exchanger 50 and piping will be described with reference to FIGS. 3 and 4. FIG. 3 is a cross-sectional view showing a state where a hot water supply heat exchanger and a pipe are connected using a quick fastener. FIG. 4 shows a single quick fastener, where (a) is a perspective view, (b) is a side view, and (c) is a front view.

  As shown in FIG. 3, the water supply pipe 21, the hot water supply pipe 22 (bath pouring pipe 31), the hot water supply heat exchanger forward pipe 41 and the hot water supply heat exchanger return pipe 42 (hereinafter collectively referred to as a pipe H). A similar joint E is formed at the tip. That is, the joint portion E is formed with two flange portions e1 and e2 on the outer peripheral surface of the tip of the pipe H with a predetermined interval in the axial direction, and an O-ring R in the concave portion between the flange portion e1 and the flange portion e2. Is arranged.

  On the other hand, in the hot water supply heat exchanger 50, a substantially cylindrical joint F is fixed to a portion to which the pipe H is connected by welding or the like. The joint F is formed such that the cylindrical portion f1 protrudes from the surface of the hot water supply heat exchanger 50, and the flange portion f2 protrudes outward over the entire circumference at the tip of the cylindrical portion f1 on the side where the pipe H is inserted. Has been. Note that the internal structure of the hot water supply heat exchanger 50 is omitted.

  When the joint portion E is inserted into the insertion hole f3 of the joint F configured as described above, the O-ring R comes into contact with the insertion hole f3 and is elastically deformed, thereby closely contacting the inner wall surface of the insertion hole f3. It is designed not to leak water from the part.

  As shown in FIGS. 4A to 4C, the quick fastener 52 of FIG. 3 is formed by press working using, for example, a stainless steel plate, and a pair of bow-shaped pipes that grip the pipe H by elastic force. Gripping portions 52a, 52a, a pair of bow-shaped joint gripping portions 52b, 52b for gripping the joint F by elastic force, and a flange insertion hole 52c into which the flange portion f2 formed on the joint F is inserted and engaged. 52c, at one end (upper side in the figure), between the pipe gripping parts 52a, between the joint gripping parts 52b, at the connecting part 52d that connects the pipe gripping part 52a and the joint gripping part 52b, and at the other end (lower side in the figure) The pipe gripping portion 52a and the joint gripping portion 52b are connected to each other, and mounting guides 52e and 52e extending outward are provided.

After inserting the joint E into the joint F, the quick fastener 52 is pressed from the mounting guide 52e side so that the pipe gripping part 52a faces the pipe H and the joint gripping part 52b faces the joint F. Thus, the pipe gripping portion 52a and the joint gripping portion 52b are respectively spread by the pressing force, and the pipe H and the joint F are gripped by elastically returning by overcoming the pipe gripping portion 52a and the joint gripping portion 52b. Connected. At this time, when the flange portion f2 of the joint F enters the flange portion insertion hole 52c, the pipe H and the joint F are connected, and the pipe H does not come out of the hot water supply heat exchanger 50.

  The attaching / detaching mechanism is not limited to the quick fastener 52 that connects the pipe fixing member (joint F) and the pipe H by an elastic force, and can be fixed so that the pipe H does not come off the pipe fixing member. Anything may be used. Further, regarding the number of installed O-rings R, a plurality of O-rings R may be provided in the axial direction by increasing the flange portion.

<Removal procedure of hot water heat exchanger>
As shown in FIG. 1, the hot water supply heat exchanger 50 is connected to a general hot water supply circuit 20, a bathtub hot water supply circuit 30, and a hot water supply heating circuit 40. For this reason, before removing the hot water supply heat exchanger 50 from the water heater 1, it is necessary to discharge the hot water in each circuit.
The removal procedure of the hot water supply heat exchanger 50 will be described with reference to FIG. FIG. 5 is a flowchart illustrating a procedure for removing the hot water supply heat exchanger 50.
In the following description, a state where the relief valve 90 automatically opens / closes based on the pressure in the heat storage tank 10 is referred to as an operation state, and a state where the relief valve 90 is manually opened is referred to as an open state. .
At the start of the detaching operation, the water tap 99 is opened, and the pump air vent plug 43a, the pump water drain plug 44a, the tank drain plug 95, the feed water drain plug 97, and the hot water tap drain 98 are closed. The relief valve 90 is in an operating state. The electromagnetic valve 37 is also closed.

  In step S101, the replacement operator closes the water tap 99. Thereby, the water supply to the water heater 1 is stopped.

In step S102, the replacement operator opens the pump air vent plug 43a.
In step S103, the replacement worker opens the relief valve 90. Thereby, air flows in from the relief valve 90, and the primary circuit of the hot water supply heating circuit 40 (the hot water supply heat exchanger forward pipe 41, the hot water supply heat exchanger return pipes 42, 43) and the hot water supply heat exchanger 50 from the pump air vent plug 43 a. Draining of the side heat medium (hot water) is started.
In step S104, the replacement operator opens the pump drain plug 44a. Thereby, the heating medium 40 for the hot water supply (hot water supply heat exchanger forward pipe 41, the hot water supply heat exchanger return pipes 42 and 43) and the heat medium (hot water) on the primary side of the hot water supply heat exchanger 50 also from the pump drain plug 44a. Is drained.

  In step S105, the replacement operator opens the tank drain plug 95. Thereby, the heat medium (hot water) in the heat storage tank 10 is drained, and the water level in the heat storage tank 10 falls.

  In step S106, the replacement operator opens the feed water drain plug 97 and the hot water drain plug 98.

  In step S107, the replacement operator determines whether or not the drainage from the pump air vent plug 43a and the pump water drain plug 44a has been completed. If drainage has not ended (S107, No), step S107 is repeated until drainage ends. When the drainage is completed (S107 / Yes), the process proceeds to step S108. In the state where drainage from the pump air vent plug 43a and the pump water drain plug 44a has been completed, the hot water supply heat exchanger forward pipe 41 and the hot water supply heat exchanger 50 are disposed in the flow paths on the primary side (from the inlet 51c to the outlet 51d). Is drained, and the primary side pipes (the hot water supply heat exchanger forward pipe 41 and the hot water supply heat exchanger return pipe 42) can be removed. In this state, the water level in the heat storage tank 10 is lowered (see S105), and the heat medium (hot water) in the heat storage tank 10 does not flow out of the hot water supply heating circuit 40.

  In step S108, the replacement worker closes the tank drain plug 95. Thus, instead of draining all of the heat medium (hot water) in the heat storage tank 10, the piping hot water supply heat exchanger forward pipe 41 and the hot water heat exchanger return pipe 42) on the primary side of the hot water supply heat exchanger 50 are removed. After draining a part of the heat medium (hot water) in the heat storage tank 10 until a possible water level is reached (water level in which the heat medium (hot water) in the heat storage tank 10 does not flow out to the heating circuit 40 for hot water supply), the tank drain plug 95 Close the plug. For this reason, although the heat medium (hot water) remains in the heat storage tank 10, it is prevented from flowing back by the check valves 43b and 82b.

In step S109, the replacement operator removes the quick fastener 52 (see FIG. 3) at the primary side inlet 51c of the hot water heat exchanger 50, and removes the hot water heat exchanger forward pipe 41 from the hot water heat exchanger 50 (inlet 51c). .
In step S110, the replacement operator removes the quick fastener 52 (see FIG. 3) at the secondary side outlet 51b of the hot water heat exchanger 50, and connects the hot water pipe 22 (bath pouring pipe 31) to the hot water heat exchanger 50 (outlet). 51b). Here, air flows from the secondary outlet 51b of the removed hot water supply heat exchanger 50 and the hot water supply pipe 22 (bath pouring pipe 31), and the secondary hot water supply circuit 20 and the hot water supply heat exchanger 50 receive secondary water. The water is drained from the feed water drain plug 97 and the hot water drain plug 98. When drainage stops, the process proceeds to step S111. In the state where the drainage from the feed water drain plug 97 and the hot water drain plug 98 has been completed, in the flow path on the secondary side of the general hot water supply circuit 20 and the hot water heat exchanger 50 (between the inlet 51a and the outlet 51b). ) Is drained, and the secondary side pipe (water supply pipe 21) of the hot water supply heat exchanger 50 is removable.

In step S111, the replacement operator removes the quick fastener 52 (see FIG. 3) at the primary outlet 51d of the hot water heat exchanger 50, and removes the hot water heat exchanger return pipe 42 from the hot water heat exchanger 50 (exit 51d). .
In step S112, the replacement operator removes the quick fastener 52 (see FIG. 3) of the secondary side inlet 51a of the hot water supply heat exchanger 50, and removes the water supply pipe 21 from the hot water supply heat exchanger 50 (inlet 51a).
As described above, the hot water supply heat exchanger 50 can be detached from the hot water heater 1.

<Installation of hot water heat exchanger>
Next, the installation procedure of the hot water supply heat exchanger 50 will be described with reference to FIG. FIG. 6 is a flowchart for explaining the installation procedure of the hot water supply heat exchanger 50.
At the start of installation, the tank drain plug 95 and the water tap 99 are closed, and the pump air drain plug 43a, the pump water drain plug 44a, the feed water drain plug 97, and the hot water drain plug 98 are opened and released. The valve 90 is open.

  In step S201, the replacement operator attaches the pipe to the new hot water supply heat exchanger 50 and fixes it with the quick fastener 52 (see FIG. 3). That is, the hot water supply pipe 21 is inserted into the secondary side inlet 51a of the hot water supply heat exchanger 50, the hot water supply pipe 22 (bath pouring pipe 31) is inserted into the secondary side outlet 51b of the hot water supply heat exchanger 50, and hot water supply heat exchange is performed. The hot water supply heat exchanger forward pipe 41 is inserted into the primary side inlet 51c of the water heater 50, and the hot water supply heat exchanger return pipe 42 is inserted into the primary side outlet 51d of the hot water supply heat exchanger 50, and each is connected to the quick fastener 52 (see FIG. 3). ).

In step S202, the replacement operator closes the pump drain plug 44a, the feed water drain plug 97, and the hot water drain plug 98. The pump air vent plug 43a is left open.
In step S203, the replacement operator opens the water tap 99. Thereby, the water supply from a water supply source is poured into the heat storage tank 10. The air in the heat storage tank 10 is pushed up and discharged from the relief valve 90 to the outside.
In step S204, the replacement worker determines whether or not water has flowed out of the pump air vent plug 43a. When the water has not been discharged (S204 / No), step S204 is repeated until the water is discharged. When the water is discharged (S204 / Yes), the process proceeds to step S205. In the state where water is discharged from the pump air vent plug 43a, the inside of the heat storage tank 10 is full.
In step S205, the replacement operator changes the relief valve 90 from the open state to the operating state.

In step S206, the replacement operator determines whether or not the discharge of air (air) from the pump air vent plug 43a has been completed. If the air discharge has not ended (No at S206), step S206 is repeated until the air discharge ends. When the discharge of air is completed (S206, Yes), the process proceeds to step S207. In addition, in the state where the discharge of air from the pump air vent plug 43a has been completed, the air venting in the hot water supply heating circuit 40, the hot water supply heat exchanger 50, and the hot water supply circulation pump 44 has been completed.
In step S207, the replacement operator closes the pump air vent plug 43a.
As described above, the hot water supply heat exchanger 50 can be attached to the water heater 1.
In addition, although the air in the general hot water supply circuit 20 (tub hot water supply circuit 30) is not discharged | emitted, when the general hot water supply terminal A (solenoid valve 37) is opened, it is pushed out with hot water supply.

<Summary>
As described above, according to the water heater 1 of the present embodiment, the hot water in the heat storage tank 10 is not used for general hot water supply or bathtub hot water supply, that is, the hot water in the heat storage tank 10 returns to the total amount of heat storage tank 10. Since it is comprised in this way, it becomes possible to use water with high hardness, such as tap water with high hardness, well water, and groundwater. Moreover, even when such high-hardness water is used, it is possible to prevent clogging of piping due to the scale in the high-temperature portion of the water channel in the water heater 1 (such as the primary side of the heat pump unit 3 and the hot water heat exchanger 50). can do. As a result, the heat medium in the heat storage tank 10 is not a special liquid but water similar to that used for general hot water supply or bathtub hot water supply is used. Handling becomes easier. In particular, since the condenser (water refrigerant heat exchanger) of the heat pump unit 3 is configured such that a high-pressure refrigerant flows on the primary side, only the condenser (water refrigerant heat exchanger) cannot be removed. For this reason, the hot water in the heat storage tank 10 is not used for general hot water supply or bathtub hot water supply, but is used as a heat medium to prevent clogging of piping due to the scale, thereby making the entire hot water heater 1 (or the entire heat pump unit 3). It is possible to eliminate waste such as replacement.

  Moreover, in the water heater 1 of this embodiment, as demonstrated in FIGS. 2-4, the hot water supply heat exchanger 50 is comprised so that replacement | exchange is possible. Thereby, even if the flow path of the hot water supply heat exchanger 50 is clogged due to a scale or the like, the hot water supply heat exchanger 50 is removed from the joint F after the quick fastener 52 is removed, so that the hot water supply heat exchanger 50 is removed from the heat storage tank unit 2. It can be easily removed from. In addition, it becomes easy to attach a new hot water supply heat exchanger 50 to the heat storage tank unit 2. Therefore, since only the hot water supply heat exchanger 50 needs to be replaced, it is possible to eliminate waste such as replacement of the entire hot water heater 1 (or the entire heat storage tank unit 2). In particular, when high-hardness water is supplied to the hot water heater 1, the hardness component (calcium, magnesium, etc.) flows into the secondary side of the hot water heat exchanger 50 every time in the general hot water supply mode or the bathtub hot water supply mode. There is a possibility that scale deposits on the high temperature portion of the heat exchanger 50 (near the secondary side outlet side in the hot water supply heat exchanger 50) and the flow path is clogged. In contrast, the water heater 1 of the present embodiment can easily replace only the hot water supply heat exchanger 50. For this reason, even if it is a case where high-hardness water is supplied and used for the hot water heater 1, the hot water heater 1 can be used continuously, for example by replacing | exchanging the hot water heat exchanger 50 regularly.

  In the present embodiment, the sealed heat storage tank 10 is described as an example. However, the sealed heat storage tank 10 is not limited to the sealed tank, and an open heat storage tank may be used. In the case of an open type heat storage tank, a situation occurs in which the heat medium in the heat storage tank 10 decreases mainly due to evaporation. By using an open tank, accompanying equipment is required, but the heat storage tank 10 can be made into a square cylinder instead of a cylinder, and dead space can be eliminated. As a result, the entire water heater can be reduced in size. In addition, high strength is not required, and the plate thickness can be reduced. In the case of an open-type heat storage tank, a configuration in which an electromagnetic valve that is open-controlled to replenish water supply to the heat storage tank 10 is conceivable.

  Moreover, you may have a function which alert | reports the replacement | exchange time of the hot water supply heat exchanger 50 to a user. For example, the controller 100 uses the hot water supply heat exchanger 50 (e.g., calculated from the operating time of the hot water supply circulation pump 44) or the flow rate of the hot water supply heat exchanger 50 (for example, if it is the primary side, the hot water supply circulation pump). Based on the operation time and the rotation speed of 44, and on the secondary side, the sum of the flow sensors 23 and 33a) and the hardness of the water supply source (for example, input by a remote controller), the hot water supply heat exchanger 50 is replaced. It is also possible to calculate the time, and when the time for replacement is reached (when the time for replacement approaches), the remote control or the like (not shown) displays that it is time for replacement and prompts the user to replace the hot water heat exchanger 50. Good.

1 Water heater 2 Heat storage tank unit 3 Heat pump unit (heating means)
10 Heat storage tank (tank)
20 General hot water supply circuit (hot water supply circuit)
21 Water supply pipe (water supply circuit, water supply circuit piping)
22 Hot water supply pipe (Pipe for hot water supply circuit)
30 Bathtub hot water supply circuit (hot water supply circuit)
31 Bath pouring pipe (pipe for hot water supply circuit)
40 Hot Water Supply Heating Circuit 41 Hot Water Heat Exchanger Outgoing Pipe (Pipe for Hot Water Heating Circuit)
42 Hot water supply heat exchanger return pipe (pipe for heating circuit for hot water supply)
50 Hot water supply heat exchanger (heat exchanger for hot water supply)
51a Inlet (secondary side inlet, joint)
51b outlet (secondary outlet, fitting)
51c inlet (primary side inlet, joint)
51d outlet (primary side outlet, joint)
80 Heat carrier introduction circuit A General hot water supply terminal (hot water supply terminal)
B Bathtub (hot water supply terminal)
F Fitting H Piping

Claims (2)

A tank for storing a heat medium;
Heating means for heating the heat medium stored in the tank;
A heating circuit for hot water supply that takes out the heat medium stored in the tank and returns it to the tank;
A heat exchanger for hot water supply provided in the heating circuit for hot water supply, and heating the hot water by exchanging heat with the heat medium to supply hot water;
A water supply circuit for supplying the water supply to the hot water supply heating circuit;
A hot water supply circuit for supplying the hot water heated by the heat exchanger for hot water supply to a hot water supply terminal;
A heat medium introduction circuit that branches from the water supply circuit and introduces the water supply into the tank as the heat medium;
The heat exchanger for hot water supply is
A water heater connected to a pipe of the heating circuit for hot water supply, a pipe of the water supply circuit, and a pipe of the hot water supply circuit by a detachable joint. The heat exchanger for hot water supply is
A first flow path through which the heat medium of the heating circuit for hot water supply flows;
A second flow path for flowing in the feed water supplied from the feed water circuit, exchanging heat with the heat medium flowing through the first flow path and heating it as the hot water supply;
The hot water heater according to claim 1, wherein the number of passes of the first flow path and the second flow path is an odd number of paths.

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