JP2006010153A - Water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water heater for guaranteeing normal operation by preventing the cross-connection. <P>SOLUTION: This water heater 100 has a hot water storage tank 2 having a heat exchanger 20 for flowing a heating medium heated by a gas engine 1, and a pipe unit 3 connected between the gas engine 1 and the hot water storage tank 2. The pipe unit 3 has a forward pipe 41 for sending out the heating medium to the heat exchanger 20 from the gas engine 1, a return pipe 42 for returning the heating medium to the gas engine 1 from the heat exchanger 20, a sealed circulating pipe 4 having an expansion tank 47 and a circulating pump 44 arranged in the middle of the return pipe 42, a water supply pipe 51 connected to the hot water storage tank 2, and a water supply pipe 52 connected to the forward pipe 41; and includes a water supply pipe 5 for arranging an isolating valve 56 in the middle of the water supply pipe 52, and a hot water outlet pipe 6 for extracting hot water in the hot water storage tank 2. The pipe unit 3 is incorporated into a case 101. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a closed-pipe hot water supply apparatus that collects exhaust heat, stores heat in a hot water storage tank, and supplies hot water obtained by heat exchange in the hot water storage tank.

  Electricity generated by a gas engine or the like is used for lighting or heating equipment, and the heat medium heated by the exhaust gas or engine cooling water is circulated by a circulation pump through a heat exchanger provided in a hot water tank. A gas cogeneration system that collects water supplied to a hot water tank as hot water obtained by heat exchange and uses it for hot water supply to a bathtub, heating, or drying clothes is becoming widespread. As the heat medium, water is often used, but an antifreeze solution such as brine (aqueous solution of calcium chloride or sodium chloride) or propylene glycol is used to prevent freezing at rest. For example, in Patent Document 1, a water replenishment tank is provided in an exhaust heat recovery circuit in which antifreeze heated by exhaust heat of a gas engine having a power generation function circulates, and a liquid disposed in the water replenishment tank by a controller of an auxiliary heat source device. Based on the output of the position detection electrode, when the amount of antifreeze liquid decreases, the water replenishing valve is opened to perform a certain amount of automatic water replenishment. It is described to notify the effect and prompt the replacement of the antifreeze. According to this hot water supply apparatus, there is an advantage that the concentration of the solution such as the antifreeze liquid can be controlled to a predetermined level or more.

  Although not directly related to the gas cogeneration system described above, it is necessary to prevent backflow from the secondary side water channel to the primary side water channel in the directly connected water supply pipe or bathtub water supply pipe. In order to prevent backflow to the water source, backflow prevention means (see Patent Documents 2 and 3) is provided in the pipe connected from the water supply source. Furthermore, in a closed piping system for heating and cooling and hot water supply in buildings and condominiums, an expansion tank is used to protect the pump. As the expansion tank, the inside of the pressure vessel is divided into a gas chamber and a liquid chamber by a diaphragm. A pressure tank (see Patent Document 4) is used.

A piping example of a conventional hot water supply apparatus provided with exhaust heat recovery means will be described with reference to FIG. In FIG. 3, the hot water supply device 110 includes a heat exchanger 81, a hot water storage tank 8 to which a water supply pipe 82 and a hot water discharge pipe 83 are connected, and a heat medium heated by exhaust heat of the gas engine 1 is supplied by a circulation pump 92. A circulation circuit 9 that circulates is provided. Inside the gas engine 1, a circulation circuit 17 including primary side pipes 17 a and 17 b connected between a heat exchanger 16 installed in the exhaust gas chamber 15 and a primary side of the heat exchanger 16 is provided. The first heat medium heated by the heat exchange with the circulation pump 18 is circulated by the circulation pump 18. On the other hand, in the circulation circuit 9, the second heat medium flowing into the heat exchanger 81 from the forward pipe 91a connected to the heat exchanger 19 is heat-exchanged with the water in the hot water storage tank 8, and the obtained hot water is The hot water pipe 83 is taken out. The second heat medium flowing out from the heat exchanger 81 passes through the return pipe 91b, flows into the secondary side of the heat exchanger 19, and rises in temperature by heat exchange with the first heat medium. When the temperature or pressure in the hot water storage tank 8 rises to an abnormal value, the relief valve 84 is activated and a part of the hot water (such as a drain) is discharged from the drain pipe 85. A reserve tank 93 is provided in the middle of the circulation circuit 9 in order to replenish the heat medium reduced by evaporation or the like. The reserve tank 93 has a structure open to the atmosphere and absorbs the thermal expansion of the second heat medium, and is installed so as to maintain a height difference from the heat exchanger 81. ing. In order to prevent the heat medium from leaking from the reserve tank 93, a check valve 94 is provided in the middle of the forward pipe 91a. Further, in order to maintain the water level in the reserve tank 93, a water level detection sensor 97 is provided, and when the water level falls below a predetermined level, the electromagnetic valve 96 is opened to supply water from the water pipe 95. ing.
JP 2002-267264 A (3rd to 4th pages, FIG. 1) JP 2003-336905 A (pages 3 to 4, FIG. 1) JP 2001-12629 A (pages 2 to 4, FIG. 1) Japanese Patent Laid-Open No. 6-159510 (pages 2 and 3, FIG. 1)

  According to the conventional hot water supply apparatus, the reserve tank 93 for replenishing the heat medium is open to the atmosphere, and the circulation circuit 8 through which the heat medium circulates is an open type pipe. Even if the pressure rises (for example, 60 ° C.), the pressure in the circulation circuit 8 is maintained at a constant value (for example, 0.2 MPa). There is a case where a phenomenon called cross connection occurs in which the heat medium is mixed into the hot water in the hot water storage tank 8 due to corrosion. Moreover, according to the conventional hot water supply device, since the open-type piping is adopted, it is necessary to install the reserve tank at a position higher than the heat exchanger (for example, the rooftop of the building), which greatly increases the installation conditions of the hot water supply device. Constrained by If the installation height of the reserve tank is inappropriate, there arises a problem that the heat medium leaks from the reserve tank when the heat medium expands as the temperature rises. In addition, a check valve 94 and a solenoid valve 95 are provided for preventing leakage of the heat medium from the water level detection sensor 97 and the open-type reserve tank 93, but unless a special electronic circuit is provided, a power failure will occur. For example, these means may malfunction, and normal operation may not be guaranteed. In an extreme case, the heat medium in the reserve tank 93 may flow backward to the water pipe 95 and another cross connection may occur. In addition, it is conceivable to provide warning means (alarms, etc.) in order to quickly replenish water when the water level in the reserve tank drops, but it is not possible to monitor the hot water supply device at all times. Can't be.

  Accordingly, an object of the present invention is to provide a hot water supply apparatus that can prevent cross connection and that ensures normal operation.

  Another object of the present invention is to provide a hot water supply apparatus having a high degree of freedom in installation conditions.

  In order to achieve the above object, the first invention has a hot water storage tank having a heat exchanger through which a heat medium heated by a heat source flows, and a piping unit connected between the heat source and the hot water storage tank. The piping unit includes an outward pipe that sends the heat medium from the heat source to the heat exchanger, a return pipe that sends the heat medium from the heat exchanger to the heat source, and an intermediate part of the forward pipe or the return pipe. A sealed circulation pipe having a circulation pump and an expansion tank, a first water supply pipe connected to the hot water storage tank, a first water supply pipe, and a first pipe connected to the forward pipe or the return pipe. Main members of the members constituting each of the pipes, including a water supply pipe having a backflow prevention member provided in the middle of the second water supply pipe and a hot water discharge pipe for drawing out hot water in the hot water storage tank. Part is built into the case And it is characterized in Rukoto.

  In the first invention, it is preferable that a pressure relief valve is provided in the middle of the forward pipe or the return pipe, and a drain pipe for discharging the heat medium is connected to the pressure relief valve.

  In the first invention, the forward pipe or the return pipe preferably has a flow path switching member connected to the drain pipe in the middle thereof.

  In 1st invention, it is preferable that the mixing member which mixes the water branched from the middle of the hot water which flows out from the said hot water storage tank, and the said water supply piping in the said case is provided.

  In order to achieve the above object, the second invention comprises a hot water storage tank having a heat exchanger through which a heat medium heated by a heat source flows, and a piping unit connected between the heat source and the hot water storage tank. The piping unit includes an outward pipe that sends the heat medium from the heat source to the heat exchanger, a return pipe that sends the heat medium from the heat exchanger to the heat source, and an intermediate part of the forward pipe or the return pipe. A sealed circulation pipe having a circulation pump and an expansion tank, a first water supply pipe connected to the hot water storage tank, a first water supply pipe, and a first pipe connected to the forward pipe or the return pipe. 2, a water supply pipe having a backflow prevention member provided in the middle of the second water supply pipe, and a hot water discharge pipe for drawing out hot water in the hot water storage tank. Built into the body And it is characterized in Rukoto.

  In the second invention, it is preferable that a pressure relief valve is provided in the middle of the heat exchanger, the forward pipe or the return pipe, and a drain pipe for discharging the heat medium is connected to the pressure relief valve.

  In the second invention, the forward pipe or the return pipe preferably has a flow path switching member connected to the drain pipe in the middle thereof.

  In the second invention, it is preferable that a mixing member for mixing warm water flowing out from the hot water storage tank and water branched from the middle of the water supply pipe is incorporated in the casing.

  According to the present invention, since the expansion tank that absorbs the expansion of the heat medium due to heating is provided in the middle of the circulation pipe including the heat exchanger through which the heat medium circulates, the circulation pipe is configured as a pipe cut off from the atmosphere. Therefore, the air is prevented from being mixed into the heat medium, the cross connection due to the corrosion of the piping system is prevented, and the height position where the expansion tank is installed is not restricted. In addition, by making the circulation pipe a sealed pipe, it is possible to unitize the piping system including the circulation pipe, the water supply pipe, the drain pipe, and the hot water piping for the heat medium, or to integrate this piping system with the hot water storage tank. It is also possible to make it a unit. By unitizing the piping system, even when hot water storage tanks with different sizes and capacities are required, it is possible to easily assemble a desired hot water supply device by connecting a common piping unit and a newly installed hot water storage tank. . In addition, a backflow prevention member (for example, an edge cut-off valve such as an intermediate chamber air release type backflow prevention valve) is provided in the middle of the pipe connecting the water supply pipe and the circulation pipe. Therefore, another cross connection caused by a failure of the supply pipe (water supply pipe) is prevented, and the water supply is not contaminated, so that a reliable operation can be performed.

  Further, according to the present invention, it is possible to appropriately control the pressure of the circulation pipe by providing a pressure relief valve in the middle of the circulation pipe including the heat exchanger in which the heat medium circulates. can get.

  Details of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic cross-sectional view of a hot water supply apparatus according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of a hot water supply apparatus according to another embodiment of the present invention. .

  A hot water supply apparatus 100 shown in FIG. 1 includes a gas engine 1 having a heat exchanger 10 and a heat exchanger 20 in which a heat medium flows, and is heated indirectly by exhaust heat of the gas engine 1 (for example, tap water). A hot water storage tank 2 in which water is stored, and a piping unit 3 connected between the heat exchanger 10 and the heat exchanger 20. The outlet 11 of the heat exchanger 10 is connected to the inlet 31 of the piping unit 3 via the flexible pipe 13, and the inlet 12 of the heat exchanger 10 is connected to the outlet 32 of the piping unit 3 via the flexible pipe 14. ing. The piping unit 3 includes a circulation pipe 4 including an outward pipe 41 and a return pipe 42 through which a heat medium heated by exhaust heat of the gas engine 1 flows, a water supply pipe 51 for supplying water to the hot water storage tank 2, and a circulation pipe 4 ( For example, a water supply pipe 5 including a water supply pipe 52 for supplying water to the outgoing pipe 41), a hot water discharge pipe 61 for discharging hot water from the hot water storage tank 2, a high temperature hot water discharge pipe 62 and a constant temperature hot water discharge pipe 63, Drain pipes 71, 72, 73 and 74 for draining from the circulation pipe 4 and the like and drain pipes 7 including drain pipes 77 and 76 for draining from the hot water storage tank 2 are provided. The main part of the piping member is incorporated in the case 101 indicated by a broken line, and a signal output from a control circuit (not shown) of the gas engine 1 is received in the case 101 (may be external). A control device 102 including a control circuit for controlling the operation of the circulation pipe (circulation pump described later) is installed. In FIG. 1, the temporary side of the heat exchanger 10 that performs heat exchange with the exhaust heat of the engine is omitted.

  The forward pipe 41 constituting the circulation pipe 4 is connected between the inlet 31 of the pipe unit 3 and the heat exchanger 20, and the return pipe 42 is connected between the outlet 32 of the pipe unit 3 and the heat exchanger 20. Thus, the circulation pipe 4 is configured as a sealed pipe. A three-way valve 43, a circulation pump 44, and an insulating union 45a are installed in the middle of the forward pipe 41 from upstream to downstream. In the middle of the return pipe 32, an insulating union 45b, a pressure relief valve 46, an expansion tank 47, and an air vent valve 48 are provided from upstream to downstream. The three-way valve 43 and the circulation pump 44 may be provided in the middle of the return pipe 32, and the pressure relief valve 46, the expansion tank 47, and the air vent valve 48 may be provided in the middle of the forward pipe 41, without being limited to the arrangement shown in FIG. The distance between the three-way valve 43 and the circulation pump 44 is preferably set short in order to reduce the air remaining in the circulation pipe.

  A water supply pipe 51 constituting the water supply pipe 5 is connected between the water supply port 33 and the lower part of the hot water storage tank 2, and a pressure reducing valve 53 and a union 54 are provided in the middle of the water supply pipe 51. The water supply pipe 52 branched from is connected to a heat medium inlet 49 provided in the forward pipe 41. In the middle of the water supply pipe 52, a pressure reducing valve 55 and an edge cut valve 56 for preventing a backflow are provided in order from the upstream side. However, when a liquid other than water (for example, antifreeze) is used as the heat medium, the water supply pipe 52 is omitted, and a heat medium supply pipe (both not shown) provided with a pressure reducing valve is connected to the inlet 49. Good.

The drain pipes constituting the drain pipe 7 are connected as follows. Branches from a drain pipe 71 branched from a pressure relief valve 46 provided upstream of the expansion tank 47, a drain pipe 72 branched from an edge cut valve 56, and a three-way valve 43 provided upstream of the circulation pump 44. The drainage pipe 73 thus connected is connected to a four-way joint (hereinafter referred to as a cross joint) 75, and the cross joint 75 is connected to the drainage port 34 via the drainage pipe 74, and drainage or the like is discharged from the drainage port 34. Here, the three-way valve 43, the heating medium inlet 49 and the circulation pump 44 are preferably arranged in this order along the flow direction of the heating medium, and the inlet 49 is preferably provided near the circulation pump 44.
In order to allow drainage from the hot water storage tank 2, a drain pipe 77 provided with a drain valve 79 is connected between the lower portion of the hot water storage tank 2 and the drain outlet 37. A drain pipe 76 that joins the drain pipe 77 is connected to the upper part of the hot water storage tank 2 via a relief valve 78.

  One end of a hot water pipe 61 constituting the hot water piping 6 is connected to the upper part of the hot water storage tank 2, and an air vent valve 64 and a union 65 are provided in the middle. The hot water outlet 61 is connected to a high temperature hot water outlet 62 having a hot water outlet 35, and this hot water outlet 62 is connected to a mixing valve 66, and this mixing valve 66 supplies hot (for example, 70 ° C.) hot water to the water supply pipe. The hot water adjusted to a predetermined temperature (for example, 45 ° C.) is discharged from the hot water outlet 36 through the constant temperature hot water outlet pipe 63 after mixing with the water diverted from 51. The temperature of the hot water discharged from the mixing valve 66 is preferably set in the range of 30 to 70 ° C., for example.

  The hot water supply operation by the hot water supply apparatus 100 shown in FIG. 1 will be described. First, the hot water outlet 35 to which the high temperature hot water outlet pipe 62 is connected and the hot water outlet 36 to which the constant temperature hot water outlet pipe 63 is connected are opened, and then a water supply main plug (not shown) is opened. Fill with water. Next, both the outlets 35 and 36 are closed, the three-way valve 43 is opened, and the drainage connected to the three-way valve 43 while supplying water as a heat medium to the circulation pipe 4 including the heat exchangers 10 and 20. The air is vented by the pipe 73, and after the water is filled, the three-way valve 43 is closed to stop the supply of water. In this case, as the heat medium, other liquid (for example, antifreeze liquid) may be injected from the injection port 49 in addition to water. Thereafter, the operation of the gas engine 1 is started and the circulation pump 44 is operated, so that the water (about 20 ° C.) in the circulation pipe 4 flows in the circulation pipe 4 by the heat exchanger 10. Heat exchange with 1 exhaust heat (for example, about 75 ° C.) heats to, for example, about 70 ° C. This heat medium is heat-exchanged with the water in the hot water storage tank 2 by the heat exchanger 20, so that the water in the hot water storage tank 2 having a capacity of about 50 to 500 l in about 60 minutes of operation is, for example, hot water of about 60 ° C. It becomes.

  The hot water may be discharged from the hot water outlet pipe 62 as it is, or may be mixed with water by the mixing valve 66 and discharged from the constant temperature hot water pipe 63. According to the hot water supply apparatus 100, since the heat medium circulates in the sealed pipe and is cut off from the atmosphere, air is prevented from being mixed into the pipe, thereby preventing the pipe from being corroded. Moreover, since the air in the circulation pipe 4 is vented by the drain pipe 73 provided at the lower part of the apparatus, it is possible to reliably prevent the air from entering the circulation pipe 4. By detecting the water temperature in the hot water storage tank 2 with a temperature sensor or the like provided therein, when the water temperature reaches a predetermined temperature set by, for example, a thermostat, the circulation pump 44 is stopped, and the hot water storage tank 2 When the water temperature decreases, it is desirable to drive the circulation pump 44 again.

  In the above hot water supply operation, water (heat medium) filled in the piping expands due to heating, but the expansion is absorbed by the expansion tank 47 provided in the middle of the return pipe 42, so that safe operation is possible. Done. That is, the pressure of the heating medium (5 ° C.) when tap water is supplied from the water supply pipe 51 into the hot water storage tank 2 is 0.20 Pa, but when the temperature of the heating medium rises, for example, the pressure is 40 ° C. Is 0.29 Pa, 60 ° C., and the pressure is 0.39 Pa. Thus, since the expanded heat medium compresses the sealed air and is sucked into the expansion tank 47, the expansion of the heat medium due to this pressure increase can be absorbed. Further, since the pressure relief valve 46 communicating with the drain pipe 71 is provided on the upstream side of the expansion tank 47, safe operation can be ensured even if the expansion tank 47 has a failure. Since the water supply pipe 51 is connected to the forward pipe 41 via the water supply pipe 52, water can be automatically supplied (supplemented water) into the circulation pipe 4 without providing a reserve tank. Further, since the pressure reducing prevention valve 55 is provided in the middle of the water supply pipe 52 and the edge cut-off valve 56 is provided downstream thereof, when the heat medium flows backward from the forward pipe 41, the edge cut-off valve 56 is activated to generate heat. The medium is discharged out of the unit from the drain port 34 through the drain pipe 72 and the drain pipe 74. Therefore, according to the piping configuration of FIG. 1, it is reliably prevented that the heat medium flows back into the water supply pipe 51 and eventually enters the water in the water pipe (cross connection). According to the present invention, the sealed circulation pipe 4 and the water supply pipe 51 need only be electrically connected only when water is supplied to the circulation pipe 4, and the water supply port 49 and the end of the water supply pipe connected thereto are connected to the pipe. The end can be connected using a detachable joint. Except when supplying water, the circulation pipe 4 can be a completely independent piping system. The By doing so, even when the pressure reducing valve 55 and the edge cut valve 56 malfunction due to some cause, it is possible to completely prevent the heat medium from being mixed into the clean water.

  In the hot water supply apparatus 100 described above, when the heat medium flowing out from the heat exchanger 20 expands and the pressure exceeds 0.49 MPa, the pressure relief valve 46 operates to drain the heat medium. It is preferable. The set pressure of the pressure reducing valve 55 is, for example, 0.08 to 0.15 MPa, and is preferably lower than the set pressure of the pressure relief valve 46 (for example, 0.4 to 0.5 MPa).

  In the present invention, the hot water supply apparatus can have the structure shown in FIG. 2, the same parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. That is, the hot water supply apparatus 100 includes a second heat exchanger 20 in which a heat medium flows, and a hot water storage tank 2 in which water heated by the exhaust heat of the gas engine 1 having the first heat exchanger 10 is stored. As a hot water storage unit in which a pipe member including a circulation pipe 4 through which a heat medium heated by exhaust heat of the gas engine 1 circulates, a water supply pipe 5, a hot water discharge pipe 6, and a drain pipe 7 is incorporated in the housing 103 It is configured. The hot water outlet 36 connected to the constant temperature hot water outlet pipe 63 is connected to a switching valve 68 via a supply pipe 69, and the switching valve 68 is connected to the hot water pipe 67 b of the instantaneous water heater 67 connected to the water supply pipe 67 a and the hot water supply. It is connected to the pipe 67c. In FIG. 2, the primary side of the heat exchanger 10 that performs heat exchange with the exhaust heat of the engine is omitted.

  Since the piping system of the hot water supply apparatus 100 shown in FIG. 2 is the same as that shown in FIG. 1, the hot water supply operation can be performed in the same procedure as in FIG. That is, after the hot water outlet 35 of the high temperature hot water outlet 62 and the hot water outlet 36 of the constant temperature hot water outlet pipe 63 are opened, the water supply main plug (not shown) is opened, and the hot water storage tank 2 is filled with water from the water supply pipe 22. Next, both the outlets 35 and 36 are closed, and the three-way valve 43 is opened to supply water as a heat medium to the circulation pipe 4 including the heat exchangers 10 and 20, and after the water is filled, the three-way valve 43 is closed to stop water supply. Thereafter, by starting the operation of the gas engine 1 and starting the operation of the circulation pump 44, the circulating water exchanges heat with the exhaust heat of the gas engine 1 in the heat exchanger 10 while flowing through the circulation pipe 4. Is heated by. This heat medium is heat-exchanged with the water in the hot water storage tank 2 by the heat exchanger 20, whereby the water in the hot water storage tank 2 becomes warm water. This hot water may be discharged as it is from the high temperature hot water outlet pipe 62 and supplied to, for example, a washing device (not shown). Alternatively, the hot water discharged from the high-temperature hot water discharge pipe 62 can be mixed with water by the mixing valve 66 and can flow out from the constant temperature hot water discharge pipe 63. Further, the hot water flowing out from the constant temperature hot water outlet pipe 63 is supplied to the switching valve 68 through the supply pipe 69, where it is mixed with the hot water from the instantaneous water heater 67, and then hot water supply curan (not shown) through the hot water supply pipe 67c. May be supplied. According to this hot water supply apparatus 100, the heat medium circulates in the sealed pipe and is cut off from the atmosphere, so that the air is prevented from being mixed into the pipe, thereby preventing the pipe from being corroded.

In the present invention, for example, members having the following structure can be used as the members constituting the hot water supply apparatus.
The heat exchanger provided in the hot water storage tank preferably has a structure in which copper fins are provided to increase the surface area from the viewpoint of thermal efficiency.
As an edge cut-off valve that performs a backflow prevention function, for example, a pair of check valves are connected to a main body having a relief valve, and each check valve has a structure that is biased by a spring in a direction opposite to the fluid flow direction. A valve can be used. According to this edge cut-off valve, when a fluid passes through a pair of check valves, a pressure reducing action occurs due to a pressure loss of the check valves, and a pressure is applied between the primary check valve, the intermediate chamber, and the secondary check valve. A difference occurs and backflow is prevented. That is, when the fluid flows in a predetermined direction (from the primary side to the secondary side), each check valve is opened by the pressure of the fluid with the relief valve closed. On the other hand, if the amount of water supply decreases due to the reverse siphon state or back flow occurs due to back pressure, the pressure in the intermediate chamber becomes higher than that on the primary side, which is detected by the diaphragm, and the relief valve is opened to the atmosphere. Since the drainage from the intermediate chamber is performed by being opened, it is prevented from flowing back to the primary side.

  As an expansion tank, a diaphragm that partitions a gas chamber filled with compressed gas (for example, nitrogen gas) and a liquid chamber into which a heat medium flows and is connected to a pressure reducing backflow preventer is provided inside the pressure tank. In a state where the circulation pump is stopped, the diaphragm can be deformed by the expansion pressure of the compressed gas and operate so as to discharge the heat medium.

It is a piping system diagram of a hot water supply apparatus according to an embodiment of the present invention. It is a piping system diagram of the hot water supply apparatus according to another embodiment of the present invention. It is a piping system diagram of the conventional hot water supply apparatus.

Explanation of symbols

1: gas engine, 10: heat exchanger, 11: outlet, 12: inlet, 13, 14: flexible pipe,
2: hot water storage tank, 20: heat exchanger,
3: piping unit, 31: outlet, 32: inlet, 33: water inlet, 34, 37: drain outlet, 35, 36: outlet
4: circulation pipe, 41: forward pipe, 42: return pipe, 43: three-way valve, 44: circulation pump, 45a, 45b: insulation union, 46: pressure relief valve, 47: expansion tank, 48: air vent valve, 49: Inlet,
5: Water supply pipe, 51, 52: Water supply pipe, 53: Pressure reducing valve, 54: Union, 55: Pressure reducing valve, 56: Edge cut valve,
6: tapping pipe, 61: tapping pipe, 62: tapping pipe for high temperature, 63: tapping pipe for constant temperature, 64: air vent valve, 65: union, 66: mixing valve, 67: instantaneous water heater, 67a: feed pipe, 67b: Hot water outlet pipe, 67c: Hot water supply pipe, 68: Switching valve, 69: Supply pipe,
7: Drain piping, 71, 72, 73, 74, 76, 77: Drain pipe, 75: Cross joint, 78: Relief valve, 79: Drain valve,
100: Hot water supply device, 101: Case, 102: Control device, 103: Housing

Claims (8)

A hot water storage tank having a heat exchanger through which a heat medium heated by a heat source flows, and a piping unit connected between the heat source and the hot water storage tank, the piping unit exchanging heat from the heat source A closed pipe having a forward pipe for sending the heat medium to a container, a return pipe for sending the heat medium from the heat exchanger to the heat source, a circulation pump provided in the middle of the forward pipe or the return pipe, and an expansion tank The second water supply pipe, the first water supply pipe connected to the hot water storage tank, the first water supply pipe, and the second water supply pipe connected to the forward pipe or the return pipe. Including a water supply pipe having a backflow prevention member provided in the middle of the hot water supply and a hot water supply pipe for drawing out hot water in the hot water storage tank, and a main part of the members constituting each pipe is incorporated in the case. Hot water supply device. 2. The hot water supply apparatus according to claim 1, wherein a pressure relief valve is provided in the middle of the forward pipe or the return pipe, and a drain pipe for discharging the heat medium is connected to the pressure relief valve. The hot water supply apparatus according to claim 2, wherein the forward pipe or the return pipe has a flow path switching member connected to the drain pipe in the middle thereof. The hot water supply according to any one of claims 1 to 3, wherein a mixing member is provided in the case for mixing hot water flowing out of the hot water storage tank and water branched from the middle of the water supply pipe. apparatus. A hot water storage tank having a heat exchanger through which a heat medium heated by a heat source flows, and a piping unit connected between the heat source and the hot water storage tank, the piping unit exchanging heat from the heat source A closed pipe having a forward pipe for sending the heat medium to a container, a return pipe for sending the heat medium from the heat exchanger to the heat source, a circulation pump provided in the middle of the forward pipe or the return pipe, and an expansion tank A hot water supply apparatus, wherein the hot water storage tank and the piping unit are incorporated in a housing. 6. A pressure relief valve is provided in the middle of the heat exchanger, the forward pipe or the return pipe, and a drain pipe for discharging the heat medium is connected to the pressure relief valve. Water heater. The hot water supply apparatus according to claim 6, wherein the forward pipe or the return pipe has a flow path switching member connected to the drain pipe in the middle thereof. The hot water supply according to any one of claims 5 to 7, wherein a mixing member for mixing hot water flowing out from the hot water storage tank and water branched from the middle of the water supply pipe is incorporated in the casing. apparatus.

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