JP6818865B2 - Equipment using heat pump - Google Patents

Description

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

Patent Document 1 describes an outdoor unit of a heat pump cycle device using a flammable refrigerant. This outdoor unit is a refrigerant circuit to which a compressor, an air heat exchanger, a throttle device and a water heat exchanger are connected by piping, and an excess water pressure in the water circuit for supplying water heated by the water heat exchanger. It is equipped with a pressure relief valve to prevent it from rising. As a result, even if the partition partition that separates the refrigerant circuit and the water circuit is destroyed in the water heat exchanger and the flammable refrigerant is mixed in the water circuit, the flammable refrigerant is discharged to the outside through the pressure relief valve. Can be done.

Japanese Unexamined Patent Publication No. 2013-167398

In heat pump-using equipment such as a heat pump cycle device, a pressure relief valve for a water circuit is generally provided in an indoor unit. There are various combinations of outdoor units and indoor units in heat pump-using equipment, and not only outdoor units and indoor units of the same manufacturer may be combined, but also outdoor units and indoor units of different manufacturers may be combined. Therefore, the outdoor unit described in Patent Document 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 release valve provided in the outdoor unit but also from the pressure release valve provided in the indoor unit. May occur. 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-mentioned problems, and an object of the present invention is to provide a heat pump-using device capable of suppressing leakage of a refrigerant into a room.

The device using a heat pump according to the present invention includes a refrigerant circuit that circulates a refrigerant, a heat medium circuit that circulates a heat medium, a heat exchanger that exchanges heat between the refrigerant and the heat medium, and a part of the refrigerant circuit. The outdoor unit is provided with an outdoor unit accommodating the refrigerant circuit, the other part of the refrigerant circuit, the heat medium circuit and the indoor unit accommodating the heat exchanger, and the heat medium circuit is a main circuit via the heat exchanger. The main circuit is provided at the downstream end of the main circuit, and is provided at a branch portion to which a plurality of branch circuits branching from the main circuit are connected and at the upstream end of the main circuit. It has a confluence portion to which the plurality of branch circuits merging into the main circuit are connected, and the pressure protection device and the refrigerant leakage detection device are connected to the main circuit, and the refrigerant circuit is connected. Is provided with a first breaking device and a second breaking device with the heat exchanger interposed therebetween, and the pressure protection device comprises the heat exchanger and the branching portion or the merging portion of the main circuit. The refrigerant leakage detection device is connected to a connection portion located between the one and the other, and the refrigerant leakage detection device is connected to the other of the branch portion or the confluence portion, between the other and the connection portion, or the connection portion in the main circuit. It is connected to the connection portion, and the indoor unit accommodates the first breaking device, the second breaking device, and the refrigerant leakage detecting device .

According to the present invention, even when the refrigerant leaks into the heat medium circuit, the flow of the refrigerant in the refrigerant circuit can be blocked by the first breaking device and the second breaking device. Therefore, it is possible to prevent the refrigerant from leaking into the room from the pressure protection device.

It is a circuit diagram which shows the schematic structure of the heat pump utilization apparatus which concerns on Embodiment 1 of this invention. It is a circuit diagram which shows the schematic structure of the heat pump utilization equipment which concerns on the modification of Embodiment 1 of this invention. It is explanatory drawing which shows the example of the arrangement position of the refrigerant leakage detection apparatus 98 in the heat pump utilization equipment which concerns on Embodiment 1 of this invention. It is a circuit diagram which shows the schematic structure of the heat pump utilization apparatus which concerns on Embodiment 2 of this invention.

Embodiment 1.
The heat pump utilization device according to the first embodiment of the present invention will be described. FIG. 1 is a circuit diagram showing a schematic configuration of a heat pump utilization device according to the present embodiment. In the present embodiment, the heat pump hot water supply / heating device 1000 is illustrated as a heat pump utilization device. In the following drawings including FIG. 1, the dimensional relationship and shape of each component may differ from the actual ones.

As shown in FIG. 1, the heat pump hot water supply / heating device 1000 includes a refrigerant circuit 110 for circulating a refrigerant and a water circuit 210 for circulating water. Further, the heat pump hot water supply / heating device 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 kitchen, a bathroom, a laundry room, or a storage space such as a storage room inside a building.

The refrigerant circuit 110 has a configuration in which the compressor 3, the refrigerant flow path switching device 4, the load side heat exchanger 2, the decompression device 6, and the heat source side heat exchanger 1 are sequentially connected in an annular shape via the refrigerant pipes. There is. In the refrigerant circuit 110 of the heat pump hot water supply / heating device 1000, the refrigerant is circulated in the opposite directions to the normal operation (for example, heating / hot water supply operation) for heating the water flowing through the water circuit 210 and the heat source side heat exchanger 1. It is possible to perform a defrosting operation that defrosts the water.

The compressor 3 is a fluid machine that compresses the sucked low-pressure refrigerant and discharges it as the high-pressure refrigerant. The compressor 3 of this example is provided with an inverter device or the like, and the capacity (the amount of refrigerant delivered per unit time) can be changed by arbitrarily changing the drive frequency.

The refrigerant flow path switching device 4 switches the flow direction of the refrigerant in the refrigerant circuit 110 between the normal operation and the defrosting operation. As the refrigerant flow path 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 is a thin plate that separates the refrigerant flow path through which the refrigerant flows as a part of the refrigerant circuit 110, the water flow path through which water flows as a part of the water circuit 210, and the refrigerant flow path and the water flow path. It has a shape-like partition wall. 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 defrosting operation.

The vacuum distillation device 6 adjusts the flow rate of the refrigerant, for example, adjusting the pressure of the refrigerant flowing through the load side heat exchanger 2. The pressure reducing device 6 of this example is an electronic expansion valve capable of changing the opening degree based on an instruction from the control device 101 described later. As the pressure reducing device 6, a temperature-sensitive expansion valve (for example, a temperature-sensitive expansion valve integrated with a solenoid valve) can also be used.

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 the 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 as a condenser (radiator) during defrosting operation.

A breaking device 77 is provided as a first breaking device on the upstream side of the load side heat exchanger 2 in the flow of the refrigerant during normal operation. The shutoff device 77 is provided on the downstream side of the compressor 3 and on the upstream side of the load side heat exchanger 2 in the refrigerant circuit 110 in the flow of the refrigerant during normal operation. When the refrigerant flow path switching device 4 is provided as in the present embodiment, the breaking device 77 is located on the downstream side of the refrigerant flow path switching device 4 in the refrigerant circuit 110 in the flow of the refrigerant during normal operation. Therefore, it is preferable that the heat exchanger 2 on the load side is provided on the upstream side. As the shutoff device 77, an on-off valve (for example, a solenoid valve, a flow rate adjusting valve, an electronic expansion valve, etc.) controlled by a control device 101 described later is used. The shutoff device 77 is in the open state during the operation of the refrigerant circuit 110 including the normal operation and the defrosting operation. The shutoff device 77 shuts off the flow of the refrigerant when it is closed under the control of the control device 101.

Further, a breaking device 78 is provided as a second breaking device on the downstream side of the load side heat exchanger 2 in the flow of the refrigerant during normal operation. The shutoff device 78 is provided on the downstream side of the load side heat exchanger 2 and on the upstream side of the heat source side heat exchanger 1 in the refrigerant circuit 110 in the flow of the refrigerant during normal operation. As the shutoff device 78, an on-off valve (for example, a solenoid valve, a flow rate adjusting valve, an electronic expansion valve, etc.) controlled by a control device 101 described later is used. The shutoff device 78 is in the open state during the operation of the refrigerant circuit 110 including the normal operation and the defrosting operation. When the shutoff device 78 is closed under the control of the control device 101, the shutoff device 78 shuts off the flow of the refrigerant.

Here, when the pressure reducing device 6 is an electronic expansion valve or a solenoid valve integrated temperature-sensitive expansion valve, the pressure reducing device 6 can also serve as a shutoff device 78. That is, when the pressure reducing device 6 is an electronic expansion valve or a solenoid valve integrated temperature-sensitive expansion valve, the installation of the shutoff device 78 can be omitted, and the pressure reducing device 6 can also function as the second shutoff device. In other words, when the shutoff device 78 is an electronic expansion valve or a solenoid valve integrated temperature-sensitive expansion valve, the installation of the pressure reducing device 6 can be omitted, and the shutoff device 78 can also function as the pressure reducing device.

As the refrigerant circulating in the refrigerant circuit 110, for example, a slightly flammable refrigerant such as R1234yf and R1234ze (E) or a highly 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 kinds are mixed. Hereinafter, a refrigerant having a flammability of a slight combustion level or higher (for example, 2 L or more in the classification of ASHRAE34) may be referred to as a “flammable refrigerant” or a “flammable refrigerant”. Further, as the refrigerant circulating in the refrigerant circuit 110, nonflammable refrigerants such as R407C and R410A having nonflammability (for example, 1 in the classification of ASHRAE34) can be used. These refrigerants have a higher density than air under atmospheric pressure (eg, temperature is room temperature (25 ° C.)). Further, 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 path switching device 4, the breaking device 77, the load side heat exchanger 2, the breaking device 78, the depressurizing device 6, and the heat source side heat exchanger 1 are all housed in the outdoor unit 100. ing.

Further, the outdoor unit 100 is mainly controlled to control the operation of the refrigerant circuit 110 (for example, the compressor 3, the refrigerant flow path switching device 4, the shutoff devices 77 and 78, the depressurizing device 6, the outdoor blower (not shown), etc.). The device 101 is provided. The control device 101 has a microcomputer provided with a CPU, ROM, RAM, I / O port, and the like. The control device 101 can communicate with each other with the control device 201 and the operation unit 202, which will be described later, via the 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 normal operation in the refrigerant circuit 110 is indicated by a solid arrow. During normal operation, the refrigerant flow path is switched by the refrigerant flow path switching device 4 as shown by the solid line 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 path switching device 4 and the open state shutoff device 77. During normal operation, the load side heat exchanger 2 functions as a condenser. That is, in the load side heat exchanger 2, heat exchange is performed between the refrigerant flowing in the refrigerant flow path and the water flowing in the water flow path, and the heat of condensation of the refrigerant is dissipated to the water. As a result, the refrigerant flowing through the refrigerant flow path of the load side heat exchanger 2 is condensed into 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 dissipation from the refrigerant.

The high-pressure liquid refrigerant condensed by the load-side heat exchanger 2 flows into the decompression device 6 via the shutoff device 78 in the open state, and is decompressed to become 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 is performed between the refrigerant flowing inside and the outdoor air blown by the outdoor blower, and the heat of vaporization of the refrigerant is absorbed from the outdoor air. As a result, the refrigerant that has flowed into the heat source side heat exchanger 1 evaporates to become a low-pressure gas refrigerant. The low-pressure gas refrigerant is sucked into the compressor 3 via the refrigerant flow path switching device 4. The refrigerant sucked into the compressor 3 is compressed to become a high-temperature and high-pressure gas refrigerant. In normal operation, the above cycle is continuously repeated.

Next, an example of 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 line arrow. During the defrosting operation, the refrigerant flow path is switched by the refrigerant flow path switching device 4 as shown by the broken arrow 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 path 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 adhering to the surface of the heat source side heat exchanger 1. As a result, the refrigerant flowing inside the heat source side heat exchanger 1 is condensed into a high-pressure liquid refrigerant. Further, the frost adhering to the surface of the heat source side heat exchanger 1 is melted by heat dissipation from the refrigerant.

The high-pressure liquid refrigerant condensed by the heat source side heat exchanger 1 becomes a low-pressure two-phase refrigerant via the decompression device 6, and flows into the refrigerant flow path of the load side heat exchanger 2 through the open shutoff device 78. To do. 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 is performed between the refrigerant flowing in the refrigerant flow path and the water flowing in the water flow path, and the heat of vaporization of the refrigerant is absorbed from the water. As a result, the refrigerant flowing through the refrigerant flow path of the load side heat exchanger 2 evaporates to become a low-pressure gas refrigerant. This gas refrigerant is sucked into the compressor 3 via the shutoff device 77 in the open state and the refrigerant flow path switching device 4. The refrigerant sucked into the compressor 3 is compressed to become 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. The water circuit 210 of the present embodiment is a closed circuit that circulates water. In FIG. 1, the flow direction of water is represented by a thick white arrow. The water circuit 210 is configured by connecting the water circuit on the outdoor unit 100 side and the water circuit on the indoor unit 200 side. The water circuit 210 includes a main circuit 220, a branch circuit 221 that constitutes a hot water supply circuit, and a branch circuit 222 that forms a part of the heating circuit. The main circuit 220 forms a part of the 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 and the main circuit 220 form a closed circuit. The branch circuit 222 constitutes a closed circuit together with the main circuit 220 and the heating device 300 connected to the branch circuit 222. The heating device 300 is provided indoors separately from the indoor unit 200. As the heating device 300, a radiator, a floor heating device, or the like 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 a strainer 56, a flow switch 57, a load side heat exchanger 2, a booster heater 54, a pump 53, and the like are connected via water pipes. A drain port 62 for draining the water in the water circuit 210 is provided in the middle of the water pipe forming the main circuit 220. The downstream end of the main circuit 220 is connected to the inlet of a three-way valve 55 (an example of a branch) having one inlet and two outlets. 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 confluence 230. At the merging portion 230, the branch circuits 221 and 222 join the main circuit 220. The water circuit 210 from the merging portion 230 to the three-way valve 55 via the load side heat exchanger 2 and the like serves as the main circuit 220.

The load side heat exchanger 2 of the main circuit 220 is provided in the outdoor unit 100. Equipment other than the load side heat exchanger 2 in the main circuit 220 is provided in the indoor unit 200. That is, the main circuit 220 of the water circuit 210 is provided so as to straddle the outdoor unit 100 and the indoor unit 200. A part of the main circuit 220 is provided in the outdoor unit 100, and the other 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 connecting pipes 211 and 212 that form a part of the main circuit 220.

The pump 53 is a device that pressurizes the water in the water circuit 210 and circulates it in the water circuit 210. The booster heater 54 is a device that further heats 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 whether the water in the main circuit 220 is circulated on the branch circuit 221 side or the branch circuit 222 side. The strainer 56 is a device for removing the 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 higher than a certain amount. A flow rate sensor can be used instead 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 serves as a connection portion of the pressure release valve 70 to the water circuit 210. Hereinafter, the connection portion of the pressure release valve 70 may be simply referred to as a “connection portion”. The pressure release valve 70 is a protective device that prevents an excessive rise in pressure in the water circuit 210 due to a change in water temperature. The pressure release valve 70 discharges water to the outside of the water circuit 210 based on the pressure inside the water circuit 210. For example, when the pressure in the water circuit 210 becomes higher than the pressure control range of the expansion tank 52 (described later), the pressure relief valve 70 is opened, and the water in the water circuit 210 is discharged from the pressure relief valve 70. Is released to. The pressure release valve 70 is provided in the indoor unit 200. The pressure release valve 70 is provided in the indoor unit 200 in order to protect the pressure in the water circuit 210 in the indoor unit 200.

One end of a pipe 72 that serves 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 release valve 70 is connected to the booster heater 54 via the pipe 72. The water temperature is highest in the main circuit 220 in the booster heater 54. Therefore, the booster heater 54 is optimal as a connecting portion to which the pressure release valve 70 is connected. Further, if the pressure release valve 70 is connected to the branch circuits 221 and 222, the pressure release 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 pressure relief valves 70 may be one.

A branch portion 72a is provided in the middle of the pipe 72. One end of the pipe 75 is connected to the branch portion 72a. An 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 the pressure change in the water circuit 210 due to the temperature change of water within a certain range.

The main circuit 220 is provided with a refrigerant leakage detection device 98. The refrigerant leakage detection device 98 is connected between the load side heat exchanger 2 and the booster heater 54 (connection portion) in the main circuit 220. The refrigerant leak detection device 98 is a device that detects the leakage of the 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 rises. Therefore, the refrigerant leakage detection device 98 can detect the leakage of the refrigerant to the water circuit 210 based on the pressure (pressure value or time change of pressure) in the water circuit 210. As the refrigerant leakage 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 type or a mechanical type using a diaphragm. The refrigerant leakage detection device 98 outputs a detection signal to the control device 101.

In this example, the shutoff devices 77 and 78 and the refrigerant leak detection device 98 are both provided in the outdoor unit 100. As a result, the control device 101, the shutoff devices 77, 78, and the refrigerant leak detection device 98 can be connected to each other in the outdoor unit 100 via the control line, so that the cost can be reduced. Further, since the control (described later) of the shutoff devices 77 and 78 based on the detection signal from the refrigerant leakage detection device 98 is completed in the outdoor unit 100, the versatility of the outdoor unit 100 is enhanced, and the outdoor unit 100 and various indoor units are enhanced. The degree of freedom of combination with is improved. When the refrigerant leakage detection device 98 outputs a contact signal at the time of refrigerant leakage, the refrigerant leakage detection device 98 and the breaking devices 77 and 78 may be directly connected without the control device 101.

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 confluence 230. A coil 61 is provided in the branch circuit 221. The coil 61 is built in a hot water storage tank 51 that stores water inside. The coil 61 is a heating means for heating the water stored inside the hot water storage tank 51 by exchanging heat with the water (hot water) circulating in the branch circuit 221 of the water circuit 210. Further, the hot water storage tank 51 has a built-in flood heater 60. The flood heater 60 is a heating means for further heating the water stored inside 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 the upper part of the hot water storage tank 51. A sanitary circuit side pipe 81b (for example, a make-up water pipe) is connected to the lower part of the hot water storage tank 51. At the lower part of the hot water storage tank 51, a drain port 63 for draining the water in the hot water storage tank 51 is provided. The hot water storage tank 51 is covered with a heat insulating material (not shown) in order to prevent the temperature of the water inside from dropping due to heat dissipation to the outside. As the heat insulating material, for example, felt, Thinsulate (registered trademark), VIP (Vacuum Insulation Panel) and the like are used.

The branch circuit 222 that forms a part of the heating circuit is provided in the indoor unit 200. The branch circuit 222 has an forward pipe 222a and a return pipe 222b. The upstream end of the outgoing pipe 222a is connected to the other outlet of the three-way valve 55. The downstream end of the outgoing pipe 222a and the upstream end of the return pipe 222b are connected to the heating circuit side pipes 82a and 82b, respectively. The downstream end of the return pipe 222b is connected to the merging portion 230. As a result, the forward 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 and 82b and the heating device 300 are provided indoors but outside the indoor unit 200. The branch circuit 222 constitutes 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 release valve 301 is a protective device for preventing an excessive rise in pressure in the water circuit 210, and has a structure similar to that of the pressure release valve 70, for example. 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 release valve 301 is provided indoors but outside the indoor unit 200.

The heating device 300, the heating circuit side pipes 82a and 82b, and the pressure relief valve 301 in the present embodiment are not a part of the heat pump hot water supply / heating device 1000, but are facilities constructed by a local contractor according to the circumstances of each property. is there. For example, in an existing facility in which a boiler is used as a heat source machine for the heating device 300, the heat source machine may be updated to the heat pump hot water supply / heating device 1000. In such a case, if there is no particular inconvenience, 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 / heating device 1000 can be connected to various facilities regardless of the presence / 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, etc.). The control device 201 has a microcomputer provided with a CPU, ROM, RAM, I / O port, and the like. The control device 201 can communicate with the control device 101 and the operation unit 202.

The operation unit 202 is configured so that the user can operate the heat pump hot water supply / heating device 1000 and perform various settings. The operation unit 202 of this example includes a display unit 203 as a notification unit for notifying information. The display unit 203 can display various information such as the state of the heat pump hot water supply / heating device 1000. The operation unit 202 is provided, for example, on the surface of the housing of the indoor unit 200.

Next, in the load side heat exchanger 2, the operation when the partition wall that separates the refrigerant flow path and the water flow path is damaged will be described. The load side heat exchanger 2 functions as an evaporator during the defrosting operation. Therefore, the partition wall of the load side heat exchanger 2 may be damaged due to freezing of water or the like, especially during the defrosting operation. In general, 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 in 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 to the water flow path during both the normal operation and the defrosting operation, and the refrigerant is mixed in the water in the water flow path. At this time, the refrigerant mixed in the water is gasified by the decrease in pressure. Further, the pressure in the water circuit 210 rises due to the mixing of the refrigerant having a pressure higher than that of water into the water.

The refrigerant mixed in the water of the water circuit 210 in the load side heat exchanger 2 not only flows in the direction along the normal water flow (that is, in the direction from the load side heat exchanger 2 toward the booster heater 54), but also in the pressure. Due to the difference, the water flows in the direction opposite to the normal flow of water (that is, the direction from the load side heat exchanger 2 toward the confluence 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 from the pressure relief valve 301 into the room together with the water. .. That is, both the pressure release valves 70 and 301 function as valves that discharge the refrigerant mixed in the water in the water circuit 210 to the outside of the water circuit 210. When the refrigerant is flammable, if the refrigerant is released into the room, a flammable concentration range may be generated in the room.

In the present embodiment, when the control device 101 detects the leakage of the refrigerant to the water circuit 210 based on the detection signal from the refrigerant leakage detection device 98, the compressor 3 is stopped and the shutoff devices 77 and 78 are closed. To. As a result, the flow of the refrigerant in the refrigerant circuit 110 is cut off at two locations before and after the load side heat exchanger 2 by the breaking devices 77 and 78. That is, the load side heat exchanger 2 is in a state of being disconnected from the refrigerant circuit 110 in the flow of the refrigerant. Therefore, the amount of refrigerant leaking to the water circuit 210 in the load-side heat exchanger 2 can be suppressed to be equal to or less than the amount of refrigerant existing in the load-side heat exchanger 2. Therefore, according to the present embodiment, it is possible to prevent the refrigerant from leaking into the room from the pressure release valves 70 and 301.

FIG. 2 is a circuit diagram showing a schematic configuration of a heat pump-using device according to a modified example of the present embodiment. As shown in FIG. 2, the present modification 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 so as to straddle the outdoor unit 100 and the indoor unit 200. A part of the refrigerant circuit 110 is provided in the outdoor unit 100, and the other part of the refrigerant circuit 110 is provided in the indoor unit 200. The outdoor unit 100 and the indoor unit 200 are connected to each other via two connecting pipes 111 and 112 that form a part of the refrigerant circuit 110. The same effect as that of the configuration shown in FIG. 1 can be obtained also by this modification. Further, in this modification, the shutoff devices 77 and 78 and the refrigerant leak detection device 98 are both provided in the indoor unit 200. The refrigerant leakage detection device 98 outputs a detection signal to the control device 201, and the blocking devices 77 and 78 are controlled by the control device 201. As a result, the control device 201, the shutoff devices 77, 78, and the refrigerant leak detection device 98 can be connected to each other in the indoor unit 200 via the control line, so that the cost can be reduced. Further, since the control of the shutoff devices 77 and 78 based on the detection signal from the refrigerant leakage detection device 98 is completed in the indoor unit 200, the versatility of the indoor unit 200 is enhanced, and the combination of the indoor unit 200 and various outdoor units is enhanced. The degree of freedom is improved.

Next, the arrangement position of the refrigerant leakage detection device 98 will be described. FIG. 3 is an explanatory diagram showing an example of the arrangement position of the refrigerant leakage detection device 98 in the heat pump utilization device according to the present embodiment. In FIG. 3, five arrangement positions A to E are shown as an example of the arrangement positions of the refrigerant leakage detection device 98. In the case of the arrangement positions A and B, the refrigerant leakage detection device 98 is connected to the pipe 72. That is, the refrigerant leakage detection device 98 is connected to the main circuit 220 by the booster heater 54 (connection portion) like the pressure relief valve 70. In such a case, the refrigerant leakage detection device 98 can reliably detect the leakage of the refrigerant before the refrigerant leaked to the water circuit 210 in the load side heat exchanger 2 is released from the pressure relief valve 70. When the leakage of the refrigerant to the water circuit 210 is detected by the refrigerant leakage detection device 98, the flow of the refrigerant in the refrigerant circuit 110 is immediately cut off by the breaking devices 77 and 78 at two locations before and after the load side heat exchanger 2. .. Therefore, the amount of refrigerant leaked from the pressure release valve 70 into the room can be minimized. The same effect can be obtained when the refrigerant leakage detection device 98 is connected to the load side heat exchanger 2 or between the load side heat exchanger 2 and the booster heater 54 in the main circuit 220. Be done.

On the other hand, in the case of the arrangement positions C and D, the refrigerant leakage detection device 98 is connected between the booster heater 54 (connection portion) and the three-way valve 55 in the main circuit 220. In this case, the refrigerant may be released from the pressure release valve 70 before the refrigerant leakage detection device 98 detects the leakage of the refrigerant. However, as described above, when the leakage of the refrigerant to the water circuit 210 is detected, the flow of the refrigerant in the refrigerant circuit 110 is immediately cut off at two locations before and after the load side heat exchanger 2. Therefore, the amount of refrigerant leaked from the pressure release valve 70 into the room can be minimized.

In the case of the arrangement position E, the refrigerant leakage detection device 98 is connected between the load side heat exchanger 2 and the merging portion 230 in the main circuit 220. In this case, the refrigerant leakage detection device 98 can reliably detect the leakage of the refrigerant before the refrigerant leaked to the water circuit 210 is released from the pressure release valve 301. When the leakage of the refrigerant to the water circuit 210 is detected by the refrigerant leakage detection device 98, the flow of the refrigerant in the refrigerant circuit 110 is immediately cut off by the breaking devices 77 and 78 at two locations before and after the load side heat exchanger 2. .. Therefore, the amount of refrigerant leaking from the pressure release valve 301 into the room can be minimized.

In all the configurations shown in FIGS. 1 to 3, the refrigerant leakage detection device 98 is not a branch circuit (for example, heating circuit side pipes 82a and 82b and a heating device 300) constructed by a local contractor, but a main circuit 220. It is connected to the. Therefore, the manufacturer of the indoor unit 200 can install the refrigerant leakage detection device 98 and connect the refrigerant leakage detection device 98 and the control device 201. Therefore, human errors such as forgetting to install the refrigerant leakage detection device 98 and forgetting to connect the refrigerant leakage detection device 98 can be avoided.

Next, the arrangement positions of the breaking devices 77 and 78 will be described. The breaking devices 77 and 78 are arranged on both sides of the refrigerant circuit 110 with the load side heat exchanger 2 interposed therebetween. In the refrigerant circuit 110, the smaller the volume of the section from the breaking device 77 to the breaking device 78 via the load side heat exchanger 2, the smaller the amount of refrigerant leaking from the pressure relief valve 70 or the pressure relief valve 301. Can be done. Therefore, it is desirable that devices having a large volume such as the compressor 3 and the heat source side heat exchanger 1 are not included in the above section. That is, it is desirable that the shutoff device 77 is provided on the upstream side of the load side heat exchanger 2 and on the downstream side of the compressor 3 in the flow of the refrigerant during normal operation. When the refrigerant flow path switching device 4 is provided in the refrigerant circuit 110 as in the present embodiment, the breaking device 77 is on the upstream side of the load side heat exchanger 2 in the flow of the refrigerant during normal operation. It is desirable that the refrigerant flow path switching device 4 is provided on the downstream side. Further, it is desirable that the shutoff device 78 is provided on the downstream side of the load side heat exchanger 2 and on the upstream side of the heat source side heat exchanger 1 in the flow of the refrigerant during normal operation.

As described above, the heat pump hot water supply / heating device 1000 (an example of a device using a heat pump) according to the present embodiment has a refrigerant circuit 110 for circulating a refrigerant and a water circuit 210 (an example of a heat medium) for circulating 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 exchanges heat between the refrigerant and water are provided. The water circuit 210 has a main circuit 220 that passes through the load side heat exchanger 2. The main circuit 220 is provided at the downstream end of the main circuit 220, and is connected to a three-way valve 55 (an example of a branch portion) to which a plurality of branch circuits 221 and 222 branching from the main circuit 220 are connected, and at the upstream end of the main circuit 220. It has a merging portion 230, which is provided and is connected to a plurality of branch circuits 221 and 222 that join the main circuit 220. 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 the refrigerant from the refrigerant circuit 110 to the water circuit 210. Is connected to the refrigerant leakage detection device 98 that detects the above. The refrigerant circuit 110 is provided with a breaking device 77 (an example of a first breaking device) and a breaking device 78 (an example of a second breaking device) with the load side heat exchanger 2 interposed therebetween.

According to this configuration, even if the refrigerant leaks to the water circuit 210, the flow of the refrigerant in the refrigerant circuit 110 can be blocked by the shutoff devices 77 and 78 at two locations before and after the load side heat exchanger 2. .. Therefore, it is possible to prevent the refrigerant from leaking into the room from the pressure release valve 70. Further, the pressure is released to the on-site construction circuit (for example, the heating circuit side pipes 82a and 82b) connected to the water circuit 210 of the indoor unit 200 before the three-way valve 55 or the merging portion 230 when viewed from the main circuit 220 side. The valve 301 may be provided. According to the above configuration, even if the pressure relief valve 301 is provided in the on-site construction circuit, it is possible to prevent the refrigerant from leaking into the room from the pressure relief valve 301.

In the heat pump hot water supply / heating device 1000 according to the present embodiment, the shutoff devices 77 and 78 are on-off valves that are closed when the leakage of the refrigerant to the water circuit 210 is detected. According to this configuration, when the refrigerant leaks into the water circuit 210, the flow of the refrigerant in the refrigerant circuit 110 can be immediately cut off.

In the heat pump hot water supply / heating device 1000 according to the present embodiment, the pressure release valve 70 is one of the load side heat exchanger 2 and the three-way valve 55 or the merging portion 230 (in this example, the three-way valve 55) in the main circuit 220. It is connected to a booster heater 54 (an example of a connection portion) located between and. The refrigerant leakage detection device 98 includes the other of the three-way valve 55 or the merging portion 230 (the merging portion 230 in this example), the other (the merging portion 230 in this example), and the booster heater 54 (connection portion) of the main circuit 220. It is connected to (an example) or a booster heater 54 (an example of a connection portion). According to this configuration, it is possible to reliably detect the leakage of the refrigerant before the refrigerant leaked to the water circuit 210 is discharged into the room.

In the heat pump hot water supply / heating device 1000 according to the present embodiment, the refrigerant leakage detection device 98 detects the leakage of the refrigerant to the water circuit 210 based on the pressure in the water circuit 210. According to this configuration, the leakage of the refrigerant can be reliably detected.

In the heat pump hot water supply / heating device 1000 according to the present embodiment, the cutoff device 77 is provided between the compressor 3 and the load side heat exchanger 2 in the refrigerant circuit 110, and the cutoff device 78 is the refrigerant circuit 110. Of these, it is provided between the load side heat exchanger 2 and the heat source side heat exchanger 1. That is, in the flow of the refrigerant in the refrigerant circuit 110 during the heating operation (normal operation in this example), the breaking device 77 is provided on the downstream side of the compressor 3 and on the upstream side of the load side heat exchanger 2. The breaking device 78 is provided on the downstream side of the load side heat exchanger 2 and on the upstream side of the heat source side heat exchanger 1. According to this configuration, the section from the breaking device 77 to the breaking device 78 via the load side heat exchanger 2 does not include a large volume device such as the compressor 3 and the heat source side heat exchanger 1. Can be done. Therefore, the amount of refrigerant leaked from the pressure release valve 70 or the pressure release valve 301 can be reduced.

In the heat pump hot water supply / heating device 1000 according to the present embodiment, the cutoff device 78 functions as a vacuum distillation device for the refrigerant circuit 110. According to this configuration, the number of parts of the heat pump hot water supply / heating device 1000 can be reduced.

The heat pump hot water supply / heating device 1000 according to the present embodiment includes an outdoor unit 100 accommodating a refrigerant circuit 110, a part of a water circuit 210, and a load side heat exchanger 2, and an indoor unit accommodating another part of the water circuit 210. It is further equipped with a machine 200. The outdoor unit 100 houses the shutoff devices 77 and 78 and the refrigerant leak detection device 98. According to this configuration, the control device 101, the shutoff devices 77 and 78, and the refrigerant leak detection device 98 can be connected to each other in the outdoor unit 100, so that the cost can be reduced. Further, according to this configuration, the versatility of the outdoor unit 100 can be enhanced, and the degree of freedom in combining the outdoor unit 100 with various indoor units can be improved.

The heat pump hot water supply / heating device 1000 according to the present embodiment has an outdoor unit 100 that houses a part of the refrigerant circuit 110, and an indoor unit that houses the other part of the refrigerant circuit 110, the water circuit 210, and the load side heat exchanger 2. It is further equipped with a machine 200. The indoor unit 200 houses the shutoff devices 77 and 78 and the refrigerant leak detection device 98. According to this configuration, the control device 201, the shutoff devices 77, 78, and the refrigerant leak detection device 98 can be connected in the indoor unit 200, so that the cost can be reduced. Further, according to this configuration, the versatility of the indoor unit 200 can be enhanced, and the degree of freedom in combining the indoor unit 200 with various outdoor units can be improved.

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

Embodiment 2.
The heat pump utilization device according to the second embodiment of the present invention will be described. FIG. 4 is a circuit diagram showing a schematic configuration of a heat pump utilization device according to the present embodiment. FIG. 4 mainly shows the configuration of the indoor unit 200. The components having the same functions and functions as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. As shown in FIG. 4, in the present embodiment, a boiling circuit 240 for heating the water stored inside the hot water storage tank 51 is provided outside the hot water storage tank 51. The boiling circuit 240 has a water flow path connecting the lower part and the upper part of the 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 the water flowing through the boiling circuit 240 and the water flowing through the branch circuit 221. When the boiling pump 241 operates, the water in the lower part of the hot water storage tank 51 flows into the boiling circuit 240. The water flowing 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. The same effect as that of the first embodiment can be obtained also by the present embodiment.

The present invention is not limited to the above embodiment and can be modified in various ways.
For example, in the above embodiment, a plate heat exchanger is given as an example as the load side heat exchanger 2, but if the load side heat exchanger 2 exchanges heat between the refrigerant and the heat medium, It may be something other than a plate heat exchanger, such as a double tube heat exchanger.

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

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

Each of the above embodiments and modifications can be implemented in combination with each other.

1 Heat source side heat exchanger, 2 Load side heat exchanger, 3 Compressor, 4 Refrigerant flow path switching device, 6 Decompression device, 51 Hot water storage tank, 52 Expansion tank, 53 Pump, 54 Booster heater, 55 Three-way valve, 56 Strainer , 57 Flow switch, 60 Flood heater, 61 Coil, 62, 63 Drain port, 70 Pressure relief valve, 72 Piping, 72a branch, 75
Piping, 77, 78 shutoff 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 Plumbing, 200 indoor unit, 201
Control device, 202 operation unit, 203 display unit, 210 water circuit, 211, 212 connection piping, 220 main circuit, 221 222 branch circuit, 222a forward pipe, 222b return pipe, 230 confluence, 240 boiling circuit, 241 boiling Lifting pump, 242 heating heat exchanger, 300 heating equipment, 301 pressure relief valve, 1000 heat pump hot water supply and heating equipment.

Claims (6)

A refrigerant circuit that circulates the refrigerant and
A heat medium circuit that distributes the heat medium and
A heat exchanger that exchanges heat between the refrigerant and the heat medium,
An outdoor unit that houses a part of the refrigerant circuit and
The other part of the refrigerant circuit, the heat medium circuit, and the indoor unit accommodating the heat exchanger are provided.
The heat medium circuit has a main circuit that passes through the heat exchanger.
The main circuit
A branching portion provided at the downstream end of the main circuit and to which a plurality of branch circuits branching from the main circuit are connected.
It has a merging portion provided at the upstream end of the main circuit and to which the plurality of branch circuits merging into the main circuit are connected.
A pressure protection device and a refrigerant leakage detection device are connected to the main circuit.
The refrigerant circuit is provided with a first breaking device and a second breaking device with the heat exchanger interposed therebetween.
The pressure protection device is connected to a connection portion of the main circuit located between the heat exchanger and the branch portion or one of the confluence portions.
The refrigerant leakage detection device is connected to the other of the branching portion or the merging portion, between the other and the connecting portion, or to the connecting portion in the main circuit .
The indoor unit is a heat pump utilization device that houses the first shutoff device, the second shutoff device, and the refrigerant leak detection device . The heat pump utilization device according to claim 1, wherein the first shutoff device and the second shutoff device are on-off valves that are closed when the leakage of the refrigerant to the heat medium circuit is detected. The heat pump utilization device according to claim 1 or 2, wherein the refrigerant leakage detection device detects leakage of the refrigerant into the heat medium circuit based on the pressure in the heat medium circuit. The first breaking device is provided between the compressor of the refrigerant circuit and the heat exchanger.
The heat pump utilization device according to any one of claims 1 to 3, wherein the second shutoff device is provided between the heat exchanger and the heat source side heat exchanger of the refrigerant circuit. The heat pump utilization device according to claim 4, wherein the second shutoff device functions as a vacuum distillation device for the refrigerant circuit. The device using a heat pump according to any one of claims 1 to 5 , wherein the refrigerant is a flammable refrigerant or a toxic refrigerant.

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