JP6664516B2 - Heat pump equipment - Google Patents

Description

  The present invention relates to a heat pump utilization device having a refrigerant circuit and a heat medium circuit.

  Patent Literature 1 describes an outdoor unit of a heat pump cycle device using a flammable refrigerant. The outdoor unit includes a refrigerant circuit to which a compressor, an air heat exchanger, a throttling device, and a water heat exchanger are connected in a pipe, and a water pressure excess in a water circuit for supplying water heated by the water heat exchanger. A pressure relief valve for preventing rise. As a result, even when the partition wall that separates the refrigerant circuit and the water circuit in the water heat exchanger is destroyed and the flammable refrigerant enters the water circuit, the flammable refrigerant is discharged to the outside via the pressure relief valve. Can be.

JP 2013-167398 A

  In equipment using a heat pump such as a heat pump cycle device, a pressure relief valve of a water circuit is generally provided in an indoor unit. There are various combinations of an outdoor unit and an indoor unit in a heat pump utilization device, and not only a case where an outdoor unit and an indoor unit of the same manufacturer are combined, but also a case where an outdoor unit and an indoor unit of different manufacturers are combined. Therefore, the outdoor unit described in Patent Literature 1 may be combined with an indoor unit provided with a pressure relief valve.

  However, in this case, when the refrigerant leaks into the water circuit, the refrigerant mixed in the water in the water circuit is discharged not only from the pressure relief valve provided in the outdoor unit but also from the pressure relief valve provided in the indoor unit. In some cases. Therefore, there is a problem that the refrigerant may leak into the room through the water circuit.

  The present invention has been made to solve the above-described problem, and has as its object to provide a heat pump-using device that can prevent a refrigerant from leaking into a room.

  The heat pump utilization device according to the present invention includes a refrigerant circuit that circulates a refrigerant, a heat medium circuit that circulates a heat medium, and a heat exchanger that performs heat exchange between the refrigerant and the heat medium. The circuit has a main circuit passing through the heat exchanger, and the main circuit is provided at a downstream end of the main circuit, and a branch unit to which a plurality of branch circuits branched from the main circuit are connected. And a junction provided at an upstream end of the main circuit and connected to the plurality of branch circuits merging with the main circuit, wherein the main circuit includes a pressure protection device and a refrigerant leak detection. A pressure protection device is connected to a connection portion of the main circuit, which is located between the heat exchanger and one of the branch portion or the junction portion; In the main circuit, between the heat exchanger and the connection portion, the heat exchange A first shut-off device capable of shutting off a flow from the heat exchanger to the connection portion, wherein the heat exchange between the heat exchanger and the other of the branch portion or the junction portion in the main circuit is provided. A second blocking device capable of blocking the flow from the vessel to the other side.

  According to the present invention, even if the refrigerant leaks into the heat medium circuit, the flow of the refrigerant mixed into the heat medium can be cut off by the cutoff device. Therefore, it is possible to prevent the refrigerant from leaking into the room from the pressure protection device.

FIG. 2 is a circuit diagram showing a schematic configuration of a heat pump utilization device according to Embodiment 1 of the present invention. FIG. 4 is a circuit diagram illustrating a schematic configuration of a heat pump utilization device according to a modification of the first embodiment of the present invention. It is an explanatory view showing an example of an arrangement position of a refrigerant leak detection device 98 in a heat pump utilization device according to Embodiment 1 of the present invention. It is an explanatory view showing an example of an arrangement position of a refrigerant leak detection device 98 in a heat pump utilization device according to Embodiment 1 of the present invention. It is an explanatory view showing an example of an arrangement position of a refrigerant leak detection device 98 in a heat pump utilization device according to Embodiment 1 of the present invention. It is an explanatory view showing an example of an arrangement position of a refrigerant leak detection device 98 in a heat pump utilization device according to Embodiment 1 of the present invention. FIG. 4 is a circuit diagram illustrating a schematic configuration of a heat pump utilization device according to Embodiment 2 of the present invention.

Embodiment 1 FIG.
A heat pump utilization device according to Embodiment 1 of the present invention will be described. FIG. 1 is a circuit diagram illustrating a schematic configuration of a heat pump utilization device according to the present embodiment. In the present embodiment, a heat pump hot water supply / room heating device 1000 is illustrated as an example of a heat pump utilization device. In the following drawings including FIG. 1, the dimensional relationships, shapes, and the like of the respective components may be different from actual ones.

  As shown in FIG. 1, the heat pump hot water supply / room heating device 1000 includes a refrigerant circuit 110 for circulating a refrigerant and a water circuit 210 for circulating water. The heat pump hot water supply / room heating apparatus 1000 includes an outdoor unit 100 installed outdoors (for example, outdoors) and an indoor unit 200 installed indoors. The indoor unit 200 is installed in, for example, a storage space such as a storage room inside a building, in addition to a kitchen, a bathroom, and a laundry room.

  The refrigerant circuit 110 includes a compressor 3, a refrigerant flow switching device 4, a load side heat exchanger 2, a first decompression device 6, an intermediate pressure receiver 5, a second decompression device 7, and a heat source side heat exchanger 1 connected to a refrigerant pipe. , And are sequentially connected in a ring shape. In the refrigerant circuit 110 of the heat pump hot water supply / room heating device 1000, a normal operation for heating the water flowing through the water circuit 210 (for example, a heating / hot water supply operation) and a refrigerant flow in the reverse direction to the normal operation are performed. And a defrosting operation for performing defrosting.

  The compressor 3 is a fluid machine that compresses the sucked low-pressure refrigerant and discharges the compressed low-pressure refrigerant as high-pressure refrigerant. The compressor 3 of the present example is provided with an inverter device and the like, and can change the capacity (the amount of refrigerant to be sent out per unit time) by arbitrarily changing the drive frequency.

  The refrigerant flow switching device 4 switches the flow direction of the refrigerant in the refrigerant circuit 110 between a normal operation and a defrosting operation. As the refrigerant flow switching device 4, for example, a four-way valve is used.

  The load side heat exchanger 2 is a water-refrigerant heat exchanger that exchanges heat between the refrigerant flowing through the refrigerant circuit 110 and the water flowing through the water circuit 210. As the load-side heat exchanger 2, for example, a plate-type heat exchanger is used. The load-side heat exchanger 2 includes a refrigerant flow path through which a refrigerant flows as part of the refrigerant circuit 110, a water flow path through which water flows as part of the water circuit 210, and a thin plate that separates the refrigerant flow path and the water flow path. And a partition in the shape of a circle. The load-side heat exchanger 2 functions as a condenser (radiator) for heating water during normal operation, and functions as an evaporator (heat absorber) during defrost operation.

  The first pressure reducing device 6 adjusts the flow rate of the refrigerant, and performs, for example, pressure adjustment of the refrigerant flowing through the load-side heat exchanger 2. The medium pressure receiver 5 is located between the first pressure reducing device 6 and the second pressure reducing device 7 in the refrigerant circuit 110 and stores excess refrigerant. A suction pipe 11 connected to the suction side of the compressor 3 passes through the inside of the intermediate-pressure receiver 5. In the intermediate pressure receiver 5, heat exchange between the refrigerant passing through the suction pipe 11 and the refrigerant in the intermediate pressure receiver 5 is performed. Therefore, the intermediate-pressure receiver 5 has a function as an internal heat exchanger in the refrigerant circuit 110. The second pressure reducing device 7 adjusts the flow rate of the refrigerant to adjust the pressure. The first decompression device 6 and the second decompression device 7 of the present example are electronic expansion valves that can change the opening based on an instruction from the control device 101 described later.

  The heat source side heat exchanger 1 is an air-refrigerant heat exchanger that exchanges heat between the refrigerant flowing through the refrigerant circuit 110 and outdoor air blown by an outdoor blower (not shown) or the like. The heat source side heat exchanger 1 functions as an evaporator (heat absorber) during normal operation, and functions as a condenser (radiator) during defrost operation.

  As the refrigerant circulating in the refrigerant circuit 110, for example, a slightly flammable refrigerant such as R1234yf and R1234ze (E) or a strongly flammable refrigerant such as R290 and R1270 is used. These refrigerants may be used as a single refrigerant, or may be used as a mixed refrigerant in which two or more types are mixed. Hereinafter, a refrigerant having a flammability level equal to or higher than the slightly flammable level (for example, 2 L or higher in the ASHRAE34 classification) may be referred to as a “flammable refrigerant” or a “flammable refrigerant”. Further, as the refrigerant circulating in the refrigerant circuit 110, non-combustible refrigerants such as R407C and R410A having noncombustibility (for example, 1 in the ASHRAE34 classification) can be used. These refrigerants have a higher density than air at atmospheric pressure (for example, at room temperature (25 ° C.)). Furthermore, as the refrigerant circulating in the refrigerant circuit 110, a toxic refrigerant such as R717 (ammonia) can be used.

  The refrigerant circuit 110 including the compressor 3, the refrigerant flow switching device 4, the load side heat exchanger 2, the first pressure reducing device 6, the medium pressure receiver 5, the second pressure reducing device 7, and the heat source side heat exchanger 1 is all outdoor. Machine 100.

  The outdoor unit 100 mainly controls the operation of the refrigerant circuit 110 (for example, the compressor 3, the refrigerant flow switching device 4, the first pressure reducing device 6, the second pressure reducing device 7, an outdoor blower (not shown), and the like). A control device 101 is provided. The control device 101 has a microcomputer including a CPU, a ROM, a RAM, an I / O port, and the like. The control device 101 can communicate with a control device 201 and an operation unit 202, which will be described later, via a control line 102.

  Next, an example of the operation of the refrigerant circuit 110 will be described. In FIG. 1, the flow direction of the refrigerant during the normal operation in the refrigerant circuit 110 is indicated by solid arrows. During normal operation, the refrigerant flow path is switched by the refrigerant flow switching device 4 as shown by the solid arrow, and the refrigerant circuit 110 is configured so that the high-temperature and high-pressure refrigerant flows into the load-side heat exchanger 2.

  The high-temperature and high-pressure gas refrigerant discharged from the compressor 3 flows into the refrigerant flow path of the load-side heat exchanger 2 via the refrigerant flow switching device 4. During normal operation, the load-side heat exchanger 2 functions as a condenser. That is, in the load side heat exchanger 2, heat exchange between the refrigerant flowing through the refrigerant flow path and the water flowing through the water flow path is performed, and the heat of condensation of the refrigerant is radiated to the water. Thereby, the refrigerant flowing through the refrigerant flow path of the load-side heat exchanger 2 is condensed to become a high-pressure liquid refrigerant. Further, the water flowing through the water flow path of the load side heat exchanger 2 is heated by heat release from the refrigerant.

  The high-pressure liquid refrigerant condensed in the load-side heat exchanger 2 flows into the first pressure reducing device 6 and is slightly reduced in pressure to become a two-phase refrigerant. The two-phase refrigerant flows into the intermediate-pressure receiver 5 and is cooled by heat exchange with the low-pressure gas refrigerant flowing through the suction pipe 11 to become a liquid refrigerant. This liquid refrigerant flows into the second decompression device 7 and is decompressed into a low-pressure two-phase refrigerant. The low-pressure two-phase refrigerant flows into the heat source side heat exchanger 1. During normal operation, the heat source side heat exchanger 1 functions as an evaporator. That is, in the heat source side heat exchanger 1, heat exchange between the refrigerant flowing inside and the outdoor air blown by the outdoor blower is performed, and the heat of evaporation of the refrigerant is absorbed from the outdoor air. Thereby, the refrigerant flowing into the heat source side heat exchanger 1 evaporates and becomes a low-pressure gas refrigerant. The low-pressure gas refrigerant flows into the suction pipe 11 via the refrigerant flow switching device 4. The low-pressure gas refrigerant flowing into the suction pipe 11 is heated by heat exchange with the refrigerant in the medium-pressure receiver 5 and is sucked into the compressor 3. The refrigerant sucked into the compressor 3 is compressed into a high-temperature and high-pressure gas refrigerant. In normal operation, the above cycle is continuously repeated.

  Next, an example of the operation during the defrosting operation will be described. In FIG. 1, the flow direction of the refrigerant during the defrosting operation in the refrigerant circuit 110 is indicated by a broken arrow. During the defrosting operation, the refrigerant flow path is switched by the refrigerant flow switching device 4 as shown by the dashed arrow, and the refrigerant circuit 110 is configured so that the high-temperature and high-pressure refrigerant flows into the heat source side heat exchanger 1.

  The high-temperature and high-pressure gas refrigerant discharged from the compressor 3 flows into the heat source side heat exchanger 1 via the refrigerant flow switching device 4. During the defrosting operation, the heat source side heat exchanger 1 functions as a condenser. That is, in the heat source side heat exchanger 1, the heat of condensation of the refrigerant flowing inside is radiated to the frost attached to the surface of the heat source side heat exchanger 1. Thereby, the refrigerant flowing inside the heat source side heat exchanger 1 is condensed and becomes a high-pressure liquid refrigerant. Further, the frost adhering to the surface of the heat source side heat exchanger 1 is melted by heat radiation from the refrigerant.

  The high-pressure liquid refrigerant condensed in the heat-source-side heat exchanger 1 becomes a low-pressure two-phase refrigerant via the second decompression device 7, the intermediate-pressure receiver 5, and the first decompression device 6, and becomes a refrigerant in the load-side heat exchanger 2. Flow into the channel. During the defrosting operation, the load-side heat exchanger 2 functions as an evaporator. That is, in the load-side heat exchanger 2, heat exchange between the refrigerant flowing through the refrigerant flow path and the water flowing through the water flow path is performed, and the heat of evaporation of the refrigerant is absorbed from the water. Thereby, the refrigerant flowing through the refrigerant flow path of the load-side heat exchanger 2 evaporates to be a low-pressure gas refrigerant. This gas refrigerant is sucked into the compressor 3 via the refrigerant flow switching device 4 and the suction pipe 11. The refrigerant sucked into the compressor 3 is compressed into a high-temperature and high-pressure gas refrigerant. In the defrosting operation, the above cycle is continuously repeated.

  Next, the water circuit 210 will be described. Water circuit 210 of the present embodiment is a closed circuit that circulates water. In FIG. 1, the flow direction of water is indicated by a thick white arrow. The water circuit 210 is configured by connecting a water circuit on the outdoor unit 100 side and a water circuit on the indoor unit 200 side. The water circuit 210 has a main circuit 220, a branch circuit 221 forming a hot water supply circuit, and a branch circuit 222 forming a part of a heating circuit. The main circuit 220 forms a part of a closed circuit. The branch circuits 221 and 222 are branched and connected to the main circuit 220, respectively. The branch circuits 221 and 222 are provided in parallel with each other. The branch circuit 221 forms a closed circuit together with the main circuit 220. The branch circuit 222 forms a closed circuit together with the main circuit 220, the heating device 300 connected to the branch circuit 222, and the like. The heating device 300 is provided indoors separately from the indoor unit 200. As the heating device 300, a radiator or a floor heating device is used.

  In the present embodiment, water is taken as an example of the heat medium flowing through the water circuit 210, but another liquid heat medium such as brine can be used as the heat medium.

  The main circuit 220 has a configuration in which the strainer 56, the flow switch 57, the load side heat exchanger 2, the booster heater 54, the pump 53, and the like are connected via a water pipe. A drain 62 for draining water in the water circuit 210 is provided in the middle of a water pipe constituting the main circuit 220. The downstream end of the main circuit 220 is connected to the inflow port of a three-way valve 55 (an example of a branch portion) having one inflow port and two outflow ports. In the three-way valve 55, the branch circuits 221 and 222 are branched from the main circuit 220. The upstream end of the main circuit 220 is connected to the junction 230. In the merging section 230, the branch circuits 221 and 222 merge with the main circuit 220. The water circuit 210 from the junction 230 to the three-way valve 55 via the load side heat exchanger 2 and the like becomes the main circuit 220.

  The load-side heat exchanger 2 of the main circuit 220 is provided in the outdoor unit 100. Devices other than the load-side heat exchanger 2 in the main circuit 220 are provided in the indoor unit 200. That is, the main circuit 220 of the water circuit 210 is provided across the outdoor unit 100 and the indoor unit 200. Part of the main circuit 220 is provided in the outdoor unit 100, and another part of the main circuit 220 is provided in the indoor unit 200. The outdoor unit 100 and the indoor unit 200 are connected via two connection pipes 211 and 212 constituting a part of the main circuit 220.

  The pump 53 is a device that pressurizes the water in the water circuit 210 and circulates the water in the water circuit 210. The booster heater 54 is a device for further heating the water in the water circuit 210 when the heating capacity of the outdoor unit 100 is insufficient. The three-way valve 55 is a device for switching the flow of water in the water circuit 210. For example, the three-way valve 55 switches between circulating water in the main circuit 220 on the branch circuit 221 side and circulating water on the branch circuit 222 side. The strainer 56 is a device for removing scale in the water circuit 210. The flow switch 57 is a device for detecting whether or not the flow rate of water circulating in the water circuit 210 is equal to or more than a certain amount. A flow sensor can be used in place of the flow switch 57.

  A pressure relief valve 70 (an example of a pressure protection device) is connected to the booster heater 54. That is, the booster heater 54 is a connection part of the pressure relief valve 70 (an example of a pressure protection device). Hereinafter, the connection part of the pressure relief valve 70 may be simply referred to as “connection part”. The pressure relief valve 70 is a protection device that prevents an excessive increase in pressure in the water circuit 210 due to a change in water temperature. The pressure relief valve 70 discharges water to the outside of the water circuit 210 based on the pressure in the water circuit 210. For example, when the pressure in the water circuit 210 rises beyond the pressure control range of the expansion tank 52 (described later), the pressure relief valve 70 is opened, and water in the water circuit 210 is released from the pressure relief valve 70 to the outside. Will be released. The pressure relief valve 70 is provided in the indoor unit 200. The reason why the pressure relief valve 70 is provided in the indoor unit 200 is to perform pressure protection in the water circuit 210 in the indoor unit 200.

  One end of a pipe 72 serving as a water flow path branched from the main circuit 220 is connected to the housing of the booster heater 54. A pressure relief valve 70 is attached to the other end of the pipe 72. That is, the pressure relief valve 70 is connected to the booster heater 54 via the pipe 72. The booster heater 54 serves as a connection part where the pressure relief valve 70 is connected to the main circuit 220. The highest water temperature in the main circuit 220 is in the booster heater 54. For this reason, the booster heater 54 is optimal as a connection portion to which the pressure relief valve 70 is connected. Further, if the pressure relief valve 70 is connected to the branch circuits 221 and 222, the pressure relief valve 70 needs to be provided for each of the branch circuits 221 and 222. In the present embodiment, since the pressure relief valve 70 is connected to the main circuit 220, the number of the pressure relief valve 70 may be one.

  A branch 72 a is provided in the middle of the pipe 72. One end of a pipe 75 is connected to the branch portion 72a. The expansion tank 52 is connected to the other end of the pipe 75. That is, the expansion tank 52 is connected to the booster heater 54 via the pipes 75 and 72. The expansion tank 52 is a device for controlling a pressure change in the water circuit 210 due to a water temperature change within a certain range.

  On the downstream side of the load side heat exchanger 2, a shutoff device 77 is provided as a first shutoff device. The shutoff device 77 is provided in the main circuit 220 between the load-side heat exchanger 2 and the booster heater 54 (that is, a connection portion to which the pressure relief valve 70 is connected). As the shutoff device 77, an on-off valve such as a solenoid valve, a flow control valve, or an electronic expansion valve is used. The shut-off device 77 is in an open state during normal operation. When the shut-off device 77 is in the closed state, the shut-off device 77 shuts off the flow from the load-side heat exchanger 2 to the booster heater 54. The shutoff device 77 is controlled by a control device 201 described later. If the connection to which the pressure relief valve 70 is connected is provided between the load-side heat exchanger 2 and the junction 230, the shutoff device 77 serves as a second shutoff device of the main circuit 220. It is provided between the load side heat exchanger 2 and the three-way valve 55 (branch).

  On the upstream side of the load-side heat exchanger 2, a shutoff device 78 is provided as a second shutoff device. The shutoff device 78 is provided between the load side heat exchanger 2 and the junction 230 in the main circuit 220. As the shutoff device 78, a check valve that allows the flow of water from the junction 230 to the load side heat exchanger 2 and blocks the flow from the load side heat exchanger 2 to the junction 230 can be used. Further, as the shutoff device 78, an on-off valve such as a solenoid valve, a flow control valve or an electronic expansion valve can be used. When an on-off valve is used as the shut-off device 78, the shut-off device 78 is controlled by the control device 201 described later or operates in conjunction with the shut-off device 77. If the connection to which the pressure relief valve 70 is connected is provided between the load-side heat exchanger 2 and the junction 230, the shut-off device 78 serves as a first shut-off device of the main circuit 220. It is provided between the load side heat exchanger 2 and the connection part.

  Downstream of the shut-off device 77, a refrigerant leak detection device 98 is provided. The refrigerant leak detection device 98 is connected between the shutoff device 77 and the booster heater 54 (connection portion) in the main circuit 220. The refrigerant leak detection device 98 is a device that detects leakage of refrigerant from the refrigerant circuit 110 to the water circuit 210. When the refrigerant leaks from the refrigerant circuit 110 to the water circuit 210, the pressure in the water circuit 210 increases. Therefore, the refrigerant leak detection device 98 can detect the leakage of the refrigerant to the water circuit 210 based on the pressure in the water circuit 210 (the value of the pressure or the time change of the pressure). As the refrigerant leak detection device 98, for example, a pressure sensor or a pressure switch (high pressure switch) for detecting the pressure in the water circuit 210 is used. For example, the pressure switch may be an electric switch or a mechanical switch using a diaphragm. The refrigerant leak detection device 98 outputs a detection signal to the control device 201.

  In this example, the shutoff devices 77 and 78 and the refrigerant leak detection device 98 are all provided in the indoor unit 200. Thus, the control device 201 can be connected to the shut-off devices 77 and 78 and the refrigerant leak detection device 98 via the control line in the indoor unit 200, so that the cost can be reduced. Both the shutoff devices 77 and 78 and the refrigerant leak detection device 98 may be provided in the outdoor unit 100. Accordingly, the control device 101 can be connected to the shut-off devices 77 and 78 and the refrigerant leakage detection device 98 via the control line in the outdoor unit 100, so that cost can be reduced.

  The branch circuit 221 constituting the hot water supply circuit is provided in the indoor unit 200. The upstream end of the branch circuit 221 is connected to one outlet of the three-way valve 55. The downstream end of the branch circuit 221 is connected to the junction 230. The branch circuit 221 is provided with a coil 61. The coil 61 is built in a hot water storage tank 51 that stores water therein. The coil 61 is a heating unit that heats the water stored in the hot water storage tank 51 by heat exchange with water (hot water) circulating in the branch circuit 221 of the water circuit 210. The hot water storage tank 51 has a built-in immersion heater 60. The immersion heater 60 is heating means for further heating the water stored in the hot water storage tank 51.

  A sanitary circuit side pipe 81a (for example, a hot water supply pipe) connected to, for example, a shower or the like is connected to an upper portion in the hot water storage tank 51. A sanitary circuit side pipe 81b (for example, a makeup water pipe) is connected to a lower portion in the hot water storage tank 51. A drain port 63 for draining water in the hot water storage tank 51 is provided at a lower portion of the hot water storage tank 51. Hot water storage tank 51 is covered with a heat insulating material (not shown) in order to prevent the temperature of the internal water from lowering due to heat radiation to the outside. As the heat insulating material, for example, felt, Thinsulate (registered trademark), VIP (Vacuum Insulation Panel), or the like is used.

  The branch circuit 222 constituting a part of the heating circuit is provided in the indoor unit 200. The branch circuit 222 has a going pipe 222a and a returning pipe 222b. The upstream end of the going pipe 222a is connected to the other outlet of the three-way valve 55. The downstream end of the going pipe 222a and the upstream end of the return pipe 222b are connected to heating circuit side pipes 82a and 82b, respectively. The downstream end of the return pipe 222b is connected to the junction 230. Thereby, the going pipe 222a and the return pipe 222b are connected to the heating device 300 via the heating circuit side pipes 82a and 82b, respectively. The heating circuit side pipes 82a, 82b and the heating device 300 are provided inside the room but outside the indoor unit 200. The branch circuit 222 forms a heating circuit together with the heating circuit side pipes 82a and 82b and the heating device 300.

  A pressure relief valve 301 is connected to the heating circuit side pipe 82a. The pressure relief valve 301 is a protection device for preventing an excessive rise in the pressure in the water circuit 210, and has, for example, a structure similar to that of the pressure relief valve 70. For example, when the pressure in the heating circuit side pipe 82a becomes higher than the set pressure, the pressure relief valve 301 is opened, and the water in the heating circuit side pipe 82a is discharged from the pressure relief valve 301 to the outside. The pressure relief valve 301 is provided inside the room but outside the indoor unit 200.

  The heating equipment 300, the heating circuit side pipes 82a and 82b, and the pressure relief valve 301 in the present embodiment are not part of the heat pump hot water supply / room heating device 1000, but are facilities installed by a local contractor according to the circumstances of each property. is there. For example, in existing equipment in which a boiler is used as a heat source device of the heating device 300, the heat source device may be updated to the heat pump hot water supply / room heating device 1000. In such a case, unless particularly inconvenient, the heating device 300, the heating circuit side pipes 82a and 82b, and the pressure relief valve 301 are used as they are. Therefore, it is desirable that the heat pump hot water supply / room heating apparatus 1000 can be connected to various facilities regardless of the presence or absence of the pressure relief valve 301.

  The indoor unit 200 is provided with a control device 201 that mainly controls the operation of the water circuit 210 (for example, the pump 53, the booster heater 54, the three-way valve 55, the shutoff device 77, and the like). The control device 201 includes a microcomputer including a CPU, a ROM, a RAM, an I / O port, and the like. The control device 201 can communicate with the control device 101 and the operation unit 202 mutually. The controller 201 sets the shut-off device 77 to a closed state when detecting leakage of the refrigerant to the water circuit 210 based on a detection signal from the refrigerant leakage detection device 98, for example. When the refrigerant leak detection device 98 outputs a contact signal at the time of refrigerant leakage, the refrigerant leak detection device 98 and the shutoff device 77 may be directly connected without the control device 201.

  The operation unit 202 allows the user to operate the heat pump hot water supply / room heating apparatus 1000 and perform various settings. The operation unit 202 of the present example includes a display unit 203. The display unit 203 can display various information such as the state of the heat pump hot water supply / room heating device 1000 and the like. The operation unit 202 is provided, for example, on the housing surface of the indoor unit 200.

  Next, an operation in the case where the partition wall that separates the refrigerant flow path and the water flow path in the load-side heat exchanger 2 is broken will be described. The load side heat exchanger 2 functions as an evaporator during the defrosting operation. For this reason, the partition wall of the load side heat exchanger 2 may be damaged due to freezing of water, especially during the defrosting operation. Generally, the pressure of the refrigerant flowing through the refrigerant flow path of the load-side heat exchanger 2 is higher than the pressure of water flowing through the water flow path of the load-side heat exchanger 2 during both the normal operation and the defrosting operation. Therefore, when the partition wall of the load-side heat exchanger 2 is damaged, the refrigerant in the refrigerant flow path flows out into the water flow path and mixes with the water in the water flow path in both the normal operation and the defrosting operation. At this time, the refrigerant mixed in the water gasifies due to a decrease in pressure. Further, the pressure in the water circuit 210 increases when the refrigerant having a higher pressure than the water is mixed into the water.

  The refrigerant mixed in the water of the water circuit 210 in the load-side heat exchanger 2 flows not only in the direction along the normal flow of water (that is, in the direction from the load-side heat exchanger 2 to the booster heater 54) but also in the pressure direction. Due to the difference, the water also flows in the opposite direction to the normal flow of the water (that is, in the direction from the load-side heat exchanger 2 to the junction 230). When the pressure relief valve 70 is provided in the main circuit 220 of the water circuit 210 as in this example, the refrigerant mixed in the water can be discharged from the pressure relief valve 70 into the room together with the water. Further, when the pressure relief valve 301 is provided in the heating circuit side pipe 82a or the heating circuit side pipe 82b as in this example, the refrigerant mixed in the water can be discharged together with the water from the pressure relief valve 301 into the room. . That is, each of the pressure relief valves 70 and 301 functions as a valve that discharges the refrigerant mixed into the water in the water circuit 210 to the outside of the water circuit 210. When the refrigerant has flammability, when the refrigerant is discharged into the room, a flammable concentration region may be generated in the room.

  However, in the present embodiment, since the shutoff device 77 is provided between the load-side heat exchanger 2 and the booster heater 54, the flow of the refrigerant from the load-side heat exchanger 2 to the booster heater 54 is interrupted. be able to. Therefore, it is possible to prevent the refrigerant from leaking into the room from the pressure relief valve 70. Further, in the present embodiment, since the shutoff device 78 is provided between the load-side heat exchanger 2 and the junction 230, the flow of the refrigerant from the load-side heat exchanger 2 to the junction 230 is interrupted. be able to. Therefore, it is possible to prevent the refrigerant from leaking into the room from the pressure relief valve 301.

  FIG. 2 is a circuit diagram showing a schematic configuration of a heat pump utilization device according to a modification of the present embodiment. As shown in FIG. 2, the present modified example is different from the configuration shown in FIG. 1 in that the load side heat exchanger 2 is housed in the indoor unit 200. The refrigerant circuit 110 is provided across the outdoor unit 100 and the indoor unit 200. A part of the refrigerant circuit 110 is provided in the outdoor unit 100, and another part of the refrigerant circuit 110 is provided in the indoor unit 200. The outdoor unit 100 and the indoor unit 200 are connected via two connection pipes 111 and 112 constituting a part of the refrigerant circuit 110. According to this modification, the same effect as the configuration shown in FIG. 1 can be obtained. Further, in the present modification, both the shutoff devices 77 and 78 and the refrigerant leak detection device 98 are provided in the indoor unit 200. Thus, the control device 201 can be connected to the shut-off devices 77 and 78 and the refrigerant leak detection device 98 via the control line in the indoor unit 200, so that the cost can be reduced.

  Next, the arrangement position of the refrigerant leak detection device 98 will be described. FIGS. 3 to 6 are explanatory diagrams showing examples of the arrangement position of the refrigerant leak detection device 98 in the heat pump utilization device according to the present embodiment. FIG. 3 shows four arrangement positions A to D as examples of arrangement positions of the refrigerant leak detection device 98. In the case of the arrangement positions A and B, the refrigerant leak detection device 98 is connected to the pipe 72. That is, the refrigerant leak detection device 98 is connected to the main circuit 220 by the booster heater 54 (connection portion), similarly to the pressure relief valve 70. In such a case, before the refrigerant leaking to the water circuit 210 in the load side heat exchanger 2 is released from the pressure relief valve 70, the refrigerant leakage detecting device 98 can reliably detect the refrigerant leakage. A similar effect is obtained when the refrigerant leak detection device 98 is connected to the load-side heat exchanger 2, between the load-side heat exchanger 2 and the booster heater 54, or to the booster heater 54 in the main circuit 220. Is also obtained.

  Further, the refrigerant gasifies when it leaks into the water circuit 210. For this reason, due to the difference in the specific volumes of the gas and the liquid, the mass velocity at the time when the refrigerant leaks from the pressure relief valve 70 is reduced to about 1/1000 of the case where the liquid refrigerant leaks. Therefore, the amount of the refrigerant that can be released from the pressure relief valve 70 in the time from when the leakage of the refrigerant is detected to when the flow is shut off by the shut-off device 77 does not reach such an amount that a combustible concentration region is generated indoors. Absent.

  On the other hand, in the case of the arrangement positions C and D, the refrigerant leak detection device 98 is connected between the booster heater 54 (connection part) and the three-way valve 55 in the main circuit 220. In this case, the refrigerant may be released from the pressure relief valve 70 before the refrigerant leakage detection device 98 detects the leakage of the refrigerant. However, due to the difference in the specific volumes of the gas and the liquid as described above, the amount of the refrigerant that can be released from the pressure relief valve 70 does not reach such an amount that a combustible concentration region is generated indoors.

  Further, as shown in FIG. 4, if the refrigerant leak detection device 98 is provided between the load side heat exchanger 2 and the shut-off device 77, the shut-off device 77 is closed immediately after the refrigerant leak is detected. By doing so, the amount of refrigerant discharged from the pressure relief valve 70 can be made substantially zero. Similarly, as shown in FIG. 5, if the refrigerant leak detection device 98 is provided between the load side heat exchanger 2 and the shutoff device 78, the amount of refrigerant released from the pressure relief valve 301 is reduced to almost zero. can do. That is, in order to make the amount of refrigerant discharged into the room almost zero, it is desirable that the refrigerant leak detection device 98 be connected between the shutoff device 77 and the shutoff device 78 in the main circuit 220.

  As shown in FIG. 6, when the shutoff device 78 is an open / close valve instead of a check valve, the refrigerant leak detection device 98 is connected between the shutoff device 78 and the junction 230 in the main circuit 220. It may be.

  In all the configurations shown in FIGS. 1 to 6, the refrigerant leak detection device 98 is not a branch circuit (for example, the heating circuit side pipes 82 a and 82 b and the heating device 300) installed by the local contractor, but a main circuit 220. It is connected to the. Therefore, the manufacturer of the indoor unit 200 can attach the refrigerant leakage detection device 98 and connect the refrigerant leakage detection device 98 to the control device 201. Therefore, human errors such as forgetting to attach the refrigerant leak detecting device 98 and forgetting to connect the refrigerant leak detecting device 98 can be avoided.

  As described above, heat pump hot-water supply / room heating device 1000 (an example of a heat pump-using device) according to the present embodiment includes a refrigerant circuit 110 that circulates a refrigerant and a water circuit 210 (an example of a heat medium) that circulates water (an example of a heat medium). An example of a medium circuit) and a load-side heat exchanger 2 (an example of a heat exchanger) that performs heat exchange between refrigerant and water. The water circuit 210 has a main circuit 220 passing through the load-side heat exchanger 2. The main circuit 220 is provided at a downstream end of the main circuit 220 and is connected to a plurality of branch circuits 221 and 222 branching from the main circuit 220 and is connected to the three-way valve 55 (an example of a branch portion). And a merging section 230 to which a plurality of branch circuits 221 and 222 merging with the main circuit 220 are connected. The main circuit 220 includes a pressure relief valve 70 (an example of a pressure protection device) that discharges water to the outside of the water circuit 210 based on the pressure in the water circuit 210, and leakage of refrigerant from the refrigerant circuit 110 to the water circuit 210. And a refrigerant leak detection device 98 for detecting the pressure. The pressure relief valve 70 is connected to the booster heater 54 (an example of a connection part) located between the load side heat exchanger 2 and one of the three-way valve 55 or the junction 230 in the main circuit 220. Between the load-side heat exchanger 2 and the booster heater 54 in the main circuit 220, a shut-off device 77 (an example of a first shut-off device) that can shut off the flow from the load-side heat exchanger 2 to the booster heater 54 is provided. Is provided. Between the load-side heat exchanger 2 and the other of the three-way valve 55 or the junction 230 in the main circuit 220, a shut-off device 78 (second shut-off) capable of cutting off the flow from the load-side heat exchanger 2 to the other end. An example of the device) is provided.

  According to this configuration, even if the refrigerant leaks to the water circuit 210 in the load-side heat exchanger 2, the flow of the refrigerant mixed in the water can be shut off by the shut-off devices 77 and 78. Therefore, it is possible to prevent the refrigerant from leaking from the pressure relief valve 70 into the room. Further, it is possible to prevent the refrigerant from leaking into the room from the pressure relief valve 301 that may be provided in a circuit (for example, the heating circuit side pipes 82a and 82b) before the branch portion.

  In heat pump hot-water supply / room heating device 1000 according to the present embodiment, shutoff devices 77 and 78 are on-off valves that close when leakage of refrigerant to water circuit 210 is detected. According to this configuration, when the refrigerant leaks into the water circuit 210, the flow of the refrigerant mixed into the water can be more reliably shut off.

  In heat pump hot water supply / room heating device 1000 according to the present embodiment, refrigerant leak detection device 98 is connected to junction portion 230, between junction portion 230 and booster heater 54, or to booster heater 54 in main circuit 220. . According to this configuration, it is possible to reliably detect the leakage of the refrigerant before the refrigerant leaking to the water circuit 210 is discharged into the room.

  In heat pump hot-water supply / room heating device 1000 according to the present embodiment, shut-off device 78 provided between load-side heat exchanger 2 and junction 230 among shut-off devices 77 and 78 is a check valve. The refrigerant leak detection device 98 is connected between the check valve and the booster heater 54 of the main circuit 220 or connected to the booster heater 54. According to this configuration, it is possible to reliably detect the leakage of the refrigerant before the refrigerant leaking to the water circuit 210 is discharged into the room.

  In heat pump hot water supply / room heating device 1000 according to the present embodiment, refrigerant leak detection device 98 is connected between shutoff device 77 and shutoff device 78 in main circuit 220. According to this configuration, the amount of refrigerant discharged from the pressure relief valve can be made substantially zero.

  In heat pump hot-water supply / room heating device 1000 according to the present embodiment, refrigerant leakage detection device 98 detects refrigerant leakage to water circuit 210 based on the pressure in water circuit 210. According to this configuration, it is possible to reliably detect leakage of the refrigerant.

  The heat pump hot water supply / room heating apparatus 1000 according to the present embodiment includes an outdoor unit 100 that houses the refrigerant circuit 110, a part of the water circuit 210 and the load side heat exchanger 2, and an indoor unit 200 that houses the other part of the water circuit 210. And further comprising. One of the outdoor unit 100 and the indoor unit 200 accommodates the shutoff devices 77 and 78 and the refrigerant leak detection device 98. According to this configuration, since the control device 101 or the control device 201 and each of the shutoff devices 77 and 78 and the refrigerant leak detection device 98 can be connected in the outdoor unit 100 or the indoor unit 200, the cost can be reduced. Become.

  The heat pump hot water supply / room heating apparatus 1000 according to the present embodiment includes an outdoor unit 100 that accommodates a part of the refrigerant circuit 110 and an indoor unit 200 that accommodates the other part of the refrigerant circuit 110, the water circuit 210, and the load-side heat exchanger 2. And further comprising. The indoor unit 200 accommodates shutoff devices 77 and 78 and a refrigerant leak detection device 98. According to this configuration, the control device 201, the shutoff devices 77 and 78, and the refrigerant leak detection device 98 can be connected in the indoor unit 200, so that the cost can be reduced.

  In heat pump hot water supply / room heating device 1000 according to the present embodiment, the refrigerant may be a flammable refrigerant or a toxic refrigerant.

Embodiment 2 FIG.
A device using a heat pump according to Embodiment 2 of the present invention will be described. FIG. 7 is a circuit diagram showing a schematic configuration of the heat pump utilization device according to the present embodiment. FIG. 7 mainly shows the configuration of the indoor unit 200. Note that components having the same functions and functions as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted. As shown in FIG. 7, in the present embodiment, a boiling circuit 240 for heating water stored in hot water storage tank 51 is provided outside hot water storage tank 51. Boiling circuit 240 has a water flow path connecting the lower part and the upper part of hot water storage tank 51. The boiling circuit 240 is provided with a boiling pump 241 and a boiling heat exchanger 242 for exchanging heat between water flowing through the boiling circuit 240 and water flowing through the branch circuit 221. When the boiling pump 241 operates, the water at the lower part of the hot water storage tank 51 flows into the boiling circuit 240. The water that has flowed into the boiling circuit 240 is heated by heat exchange in the boiling heat exchanger 242 and returns to the upper part of the hot water storage tank 51. According to the present embodiment, the same effect as in the first embodiment can be obtained.

The present invention is not limited to the above embodiment, and various modifications are possible.
For example, in the above-described embodiment, a plate-type heat exchanger has been described as an example of the load-side heat exchanger 2. However, the load-side heat exchanger 2 may be any type that performs heat exchange between a refrigerant and a heat medium. It may be other than a plate heat exchanger, such as a double tube heat exchanger.

  Further, in the above-described embodiment, the heat pump hot water supply / room heating device 1000 has been described as an example of a heat pump utilizing device, but the present invention is also applicable to other heat pump utilizing devices such as a chiller.

  Further, in the above-described embodiment, the indoor unit 200 including the hot water storage tank 51 is described as an example, but the hot water storage tank may be provided separately from the indoor unit 200.

  The above-described embodiments and modifications can be implemented in combination with each other.

  Reference Signs List 1 heat source side heat exchanger, 2 load side heat exchanger, 3 compressor, 4 refrigerant flow switching device, 5 medium pressure receiver, 6 first pressure reducing device, 7 second pressure reducing device, 11 suction pipe, 51 hot water storage tank, 52 expansion tank, 53 pump, 54 booster heater, 55 three-way valve, 56 strainer, 57 flow switch, 60 immersion heater, 61 coil, 62, 63 drain port, 70 pressure relief valve, 72 pipe, 72a branch, 75 pipe, 77, 78 shut-off device, 81a, 81b sanitary circuit side piping, 82a, 82b heating circuit side piping, 98 refrigerant leak detection device, 100 outdoor unit, 101 control device, 102 control line, 110 refrigerant circuit, 111, 112 connection piping, 200 indoor unit, 201 control device, 202 operation unit, 203 display unit, 210 water circuit, 211, 212 Connection piping, 220 main circuit, 221 and 222 branch circuit, 222a going pipe, 222b return pipe, 230 merging section, 240 boiling circuit, 241 boiling pump, 242 boiling heat exchanger, 300 heating equipment, 301 pressure relief valve , 1000 heat pump hot water supply and heating system.

Claims (9)

A refrigerant circuit for circulating the refrigerant,
A heat medium circuit for flowing a heat medium,
A heat exchanger that performs heat exchange between the refrigerant and the heat medium,
The heat medium circuit has a main circuit that passes through the heat exchanger,
The main circuit includes:
A branch unit provided at a downstream end of the main circuit and connected to a plurality of branch circuits branching from the main circuit;
A junction provided at an upstream end of the main circuit and connected to the plurality of branch circuits merging with the main circuit;
A pressure protection device and a refrigerant leak detection device are connected to the main circuit,
The pressure protection device is connected to a connection portion located between the heat exchanger and one of the branch portion or the junction portion in the main circuit,
Between the heat exchanger and the connecting portion of the main circuit, a first shut-off device capable of blocking a flow from the heat exchanger toward the connecting portion is provided,
A heat pump is provided between the heat exchanger and the other of the branch portion or the junction in the main circuit, wherein a second cutoff device capable of blocking a flow from the heat exchanger toward the other is provided. machine.   The heat pump utilization device according to claim 1, wherein the first shutoff device and the second shutoff device are on / off valves that close when leakage of the refrigerant to the heat medium circuit is detected. The said refrigerant leak detection apparatus is connected to the said other of the said branch part or the said merging part , the other of the said main circuits, and the said connection part, or the said connection part. A heat pump utilizing device according to item 1. Among the first shutoff device and the second shutoff device, the shutoff device provided between the heat exchanger and the junction is a check valve,
The heat pump utilization device according to claim 1, wherein the refrigerant leak detection device is connected between the check valve and the connection portion or the connection portion in the main circuit.   The heat pump utilization device according to any one of claims 1 to 4, wherein the refrigerant leak detection device is connected between the first shutoff device and the second shutoff device in the main circuit. .   The heat pump utilization device according to any one of claims 1 to 5, wherein the refrigerant leak detection device detects leakage of the refrigerant to the heat medium circuit based on pressure in the heat medium circuit. An outdoor unit that houses the refrigerant circuit, a part of the heat medium circuit, and the heat exchanger,
An indoor unit that houses the other part of the heat medium circuit,
The use of the heat pump according to any one of claims 1 to 6, wherein one of the outdoor unit and the indoor unit houses the first shutoff device, the second shutoff device, and the refrigerant leak detection device. machine. An outdoor unit that accommodates a part of the refrigerant circuit,
An indoor unit that houses the other part of the refrigerant circuit, the heat medium circuit and the heat exchanger,
The heat pump utilization device according to any one of claims 1 to 6, wherein the indoor unit houses the first shutoff device, the second shutoff device, and the refrigerant leak detection device.   The heat pump utilization device according to any one of claims 1 to 8, wherein the refrigerant is a flammable refrigerant or a toxic refrigerant.

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