WO2024252469A1 - Refrigeration cycle device - Google Patents

Abstract

This refrigeration cycle device comprises: a first heat medium circuit through which circulates a first heat medium having heat derived from renewable energy; a refrigerant circuit that has a compressor that compresses a first refrigerant, a first heat exchanger for performing heat exchange between the first heat medium and the first refrigerant, and a refrigerant flow path through which flows the first refrigerant of a second heat exchanger for performing heat exchange between a second heat medium and the first refrigerant; and a second heat medium circuit that is independent of the first heat medium circuit and that has a load-side heat exchanger for performing heat exchange between the second heat medium and a fluid to be heated or to be cooled, and a heat medium flow path through which the second heat medium of the second heat exchanger flows.

Description

Refrigeration Cycle Equipment

This disclosure relates to a refrigeration cycle device.

　Conventionally, it has been proposed to utilize so-called renewable energy sources such as geothermal energy in refrigeration cycle devices such as air conditioners (for example, Patent Document 1).

JP 2017-203573 A

In the field of refrigeration cycle devices, regulations have been implemented worldwide in recent years to reduce the amount of refrigerant charged. For this reason, even in refrigeration cycle devices that use unused heat, such as that in Patent Document 1, it is conceivable to reduce the amount of refrigerant charged by configuring the device so that the refrigerant circulates only inside the heat source device and a heat medium such as water circulates outside the heat source device. However, when recovering heat derived from renewable energy via a heat medium, depending on the circuit configuration, the recovered heat may be lost, and the effect of improving energy saving performance by using renewable energy may not be fully achieved.

This disclosure has been made to solve the problems described above, and aims to provide a refrigeration cycle device that suppresses the decline in energy-saving performance.

The refrigeration cycle device according to the present disclosure includes a refrigerant circuit having a first heat medium circuit in which a first heat medium having heat derived from renewable energy circulates, a compressor for compressing the first refrigerant, a first heat exchanger for performing heat exchange between the first heat medium and the first refrigerant, and a refrigerant flow path through which the first refrigerant flows in a second heat exchanger for performing heat exchange between a second heat medium and the first refrigerant, and a second heat medium circuit that is a circuit independent of the first heat medium circuit and has a load-side heat exchanger for performing heat exchange between the second heat medium and a fluid to be heated or cooled, and a heat medium flow path through which the second heat medium flows in the second heat exchanger.

In the refrigeration cycle device disclosed herein, the first heat medium circuit and the second heat medium circuit are independent. This prevents the first heat medium and the second heat medium from mixing and wasting heat derived from renewable energy. Therefore, the refrigeration cycle device disclosed herein can prevent a decrease in energy saving performance.

1 is a refrigerant circuit diagram showing a refrigeration cycle device according to a first embodiment. FIG. 2 is a hardware configuration diagram showing a control device according to the first embodiment. FIG. 2 is a hardware configuration diagram showing a control device according to the first embodiment. 1 is a functional block diagram showing a refrigeration cycle device according to a first embodiment. FIG. 4 is a refrigerant circuit diagram showing a refrigeration cycle device according to a modified example of the first embodiment. FIG. 6 is a refrigerant circuit diagram showing a refrigeration cycle device according to a second embodiment. FIG. 11 is a functional block diagram showing a refrigeration cycle device according to a second embodiment. 10 is a flowchart showing the operation of the control device according to the second embodiment. FIG. 11 is a refrigerant circuit diagram showing a refrigeration cycle device according to a third embodiment. FIG. 11 is a functional block diagram showing a refrigeration cycle device according to a third embodiment. 13 is a flowchart showing the operation of the control device according to the third embodiment. FIG. 11 is a refrigerant circuit diagram showing a refrigeration cycle device according to a fourth embodiment. FIG. 13 is a functional block diagram showing a refrigeration cycle device according to a fourth embodiment. FIG. 11 is a refrigerant circuit diagram showing a refrigeration cycle device according to a fifth embodiment. FIG. 13 is a functional block diagram showing a refrigeration cycle device according to a fifth embodiment. FIG. 13 is a refrigerant circuit diagram showing the flows of the refrigerant and the heat medium during full cooling operation and full heating operation in a refrigeration cycle device according to embodiment 5. FIG. 13 is a refrigerant circuit diagram showing the flows of the refrigerant and the heat medium during simultaneous cooling and heating operation in the refrigeration cycle device according to the fifth embodiment. FIG. 13 is a refrigerant circuit diagram showing the flows of the refrigerant and the heat medium during simultaneous cooling and heating operation in the refrigeration cycle device according to the fifth embodiment.

Below, an embodiment will be described with reference to the drawings. In each drawing, the same reference numerals are used to denote the same or equivalent parts, and this is the same throughout the entire specification. Furthermore, the forms of the components shown in the entire specification are merely examples and are not limited to these descriptions. Furthermore, the size relationships between the components in the drawings may differ from the actual ones.

Embodiment 1.
Fig. 1 is a refrigerant circuit diagram showing the flow of refrigerant during cooling operation of a refrigeration cycle apparatus 1 according to embodiment 1. The refrigeration cycle apparatus 1 of embodiment 1 is an air conditioner that performs indoor cooling and heating. In Fig. 1, the flow of refrigerant during cooling operation is indicated by a solid line, and the flow of refrigerant during heating operation is indicated by a dashed line. The refrigeration cycle apparatus 1 includes a heat source unit 2, an auxiliary heat source unit 4, and a load device 5.

In the following, an example will be described in which the refrigeration cycle device 1 is an air conditioner capable of performing at least cooling and heating operation as operating modes, but the refrigeration cycle device 1 may also be a refrigerator, freezer, or vending machine that cools stored items. The refrigeration cycle device 1 may also be a refrigeration device installed in a showcase or the like. Furthermore, the refrigeration cycle device 1 may also be a water heater that supplies hot water, or a chiller that supplies cold water.

The heat source unit 2 is, for example, an outdoor unit installed outdoors. The heat source unit 2 is a device that supplies hot or cold heat to the load device 5. The heat source unit 2 has a compressor 21, a flow path switching device 22, a refrigerant heat exchanger 23, a heat source side blower 24, a first heat exchanger 25, a second heat exchanger 26, a main throttling device 27, a sub-throttling device 28, a first heat medium pump 29, a second heat medium pump 30, and a control device 100. The compressor 21, the flow path switching device 22, the refrigerant heat exchanger 23, the first heat exchanger 25, the second heat exchanger 26, the main throttling device 27, and the sub-throttling device 28 are connected by a refrigerant piping 701 to form a refrigerant circuit 81. The refrigerant circuit 81 in the first embodiment corresponds to the "refrigerant circuit" in this disclosure, and the refrigerant circulating through the refrigerant circuit 81 corresponds to the "first refrigerant" in this disclosure.

The compressor 21 draws in low-pressure gas refrigerant, compresses it, and discharges it as high-pressure gas refrigerant. As the compressor 21, for example, a reciprocating, rotary, scroll, or screw compressor 21 is used.

The flow path switching device 22 switches between cooling operation, in which the refrigerant heat exchanger 23 functions as a condenser, and heating operation, in which the refrigerant heat exchanger 23 functions as an evaporator. The flow path switching device 22 is, for example, a four-way valve, and is controlled by the control device 100. During cooling operation, the flow path switching device 22 is switched so that the refrigerant discharged from the compressor 21 flows into the refrigerant heat exchanger 23. During heating operation, the flow path switching device 22 is switched so that the refrigerant discharged from the compressor 21 flows into the second heat exchanger 26.

The refrigerant heat exchanger 23 is, for example, a fin-tube type heat exchanger, and exchanges heat between the refrigerant flowing inside the circular or flat tubes and the outdoor air supplied by the heat source side blower 24. The refrigerant heat exchanger 23 functions as an evaporator during heating operation and as a condenser during cooling operation.

The heat source side blower 24 is a device that sends outdoor air to the refrigerant heat exchanger 23. The heat source side blower 24 is disposed adjacent to the refrigerant heat exchanger 23. By sending outdoor air from the heat source side blower 24, the efficiency of heat exchange between the refrigerant and the outdoor air is improved. As the heat source side blower 24, a propeller fan, a line flow fan (registered trademark), or a multi-blade centrifugal fan is used.

The first heat exchanger 25 is, for example, a plate-type heat exchanger, and exchanges heat between the refrigerant flowing through the refrigerant piping 701 and the first heat medium flowing through the first heat medium piping 801 described below. The first heat exchanger 25 is provided in the refrigerant piping 701 between the main throttling device 27 and the secondary throttling device 28. The first heat exchanger 25 has a refrigerant flow path 25a connected to the refrigerant piping 701 through which the refrigerant flows, and a heat medium flow path 25b connected to the first heat medium piping 801 through which the first heat medium flows. The first heat exchanger 25 functions as a condenser to condense the refrigerant during cooling operation, and as an evaporator to evaporate the refrigerant during heating operation.

The second heat exchanger 26 is, for example, a plate-type heat exchanger, and exchanges heat between the refrigerant flowing through the refrigerant piping 701 and the second heat medium flowing through the second heat medium piping 802 described below. The second heat exchanger 26 is provided in the refrigerant piping 701 between the main throttle device 27 and the flow path switching device 22. The second heat exchanger 26 has a refrigerant flow path 26a connected to the refrigerant piping 701 through which the refrigerant flows, and a heat medium flow path 26b connected to the second heat medium piping 802 through which the second heat medium flows. The second heat exchanger 26 functions as an evaporator to evaporate the refrigerant during cooling operation, and as a condenser to condense the refrigerant during heating operation.

The main throttle device 27 is an electronic expansion valve whose opening is adjustable. The main throttle device 27 is provided in the refrigerant piping 701 between the first heat exchanger 25 and the second heat exchanger 26. The main throttle device 27 reduces the pressure of the refrigerant flowing into the refrigerant heat exchanger 23 or the refrigerant flowing out of the refrigerant heat exchanger 23, causing it to expand. The opening of the main throttle device 27 is controlled by the control device 100.

The secondary throttling device 28 is an electronic expansion valve whose opening degree can be adjusted. The secondary throttling device 28 is provided in the refrigerant piping 701 between the first heat exchanger 25 and the refrigerant heat exchanger 23. The secondary throttling device 28 reduces the pressure of the refrigerant flowing into the refrigerant heat exchanger 23 or the refrigerant flowing out from the refrigerant heat exchanger 23, causing it to expand. The opening degree of the secondary throttling device 28 is controlled by the control device 100.

The first heat medium pump 29 is provided in the first heat medium pipe 801 and circulates the first heat medium. The first heat medium pump 29 is, for example, an inverter-type centrifugal pump whose capacity can be controlled.

The second heat medium pump 30 is provided in the second heat medium pipe 802 and circulates the second heat medium. The second heat medium pump 30 is, for example, an inverter-type centrifugal pump whose capacity can be controlled.

The control device 100 controls each device of the refrigeration cycle device 1. FIG. 2 is a hardware configuration diagram showing the control device 100 according to the first embodiment. As shown in FIG. 2, the control device 100 is dedicated hardware configured with a processing circuit 101 such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array). FIG. 3 is a hardware configuration diagram showing the control device 100 according to the first embodiment. When the functions of the control device 100 are performed by software, the control device 100 may be configured with a processor 102 such as a CPU and a memory 103 as shown in FIG. 3. FIG. 3 shows that the processor 102 and the memory 103 are connected to each other so as to be able to communicate with each other via a bus 104. The functions of the control device 100 are realized by the processor 102 reading and executing a program stored in the memory 103. The memory 103 may be a non-volatile or volatile semiconductor memory, or a removable recording medium. The functions of the control device 100 will be described later.

In FIG. 1, the control device 100 is provided in the heat source unit 2, but the control device 100 may be provided in the auxiliary heat source unit 4 or the load unit 5, or the heat source unit 2, the auxiliary heat source unit 4, and the load unit 5 may each be provided with a separate control device 100 and configured to communicate with each other. Also, the control device 100 may be provided in a location away from the heat source unit 2, the auxiliary heat source unit 4, and the load unit 5.

The auxiliary heat source unit 4 is a device that supplies hot or cold heat to the heat source unit 2. As will be described in detail later, the auxiliary heat source unit 4 uses renewable energy as a heat source and performs an auxiliary function to the heat source unit 2. The auxiliary heat source unit 4 has a heat medium heat exchanger 41 and a third heat medium pump 42.

The heat medium heat exchanger 41 is, for example, a plate-type heat exchanger, and performs heat exchange between the first heat medium and the third heat medium. The heat medium heat exchanger 41 has a first heat medium flow path 41a through which the first heat medium flows, and a third heat medium flow path 41b through which the third heat medium flows. The first heat medium pump 29 of the heat source unit 2, the heat medium flow path 25b of the first heat exchanger 25, and the first heat medium flow path 41a of the heat medium heat exchanger 41 are connected by a first heat medium pipe 801 through which the first heat medium flows, thereby forming a first heat medium circuit 91. For example, a calcium chloride aqueous solution, a sodium chloride aqueous solution, a magnesium chloride aqueous solution, ethylene glycol-containing brine, antifreeze, or water is used as the first heat medium.

The third heat medium flow path 41b of the heat medium heat exchanger 41 is connected to the tank 61 in which the third heat medium is stored by a third heat medium pipe 803. The third heat medium is supplied to the third heat medium flow path 41b from the tank 61 via the third heat medium pipe 803.

The third heat medium pump 42 is provided in the third heat medium piping 803 and circulates the third heat medium. The third heat medium pump 42 is, for example, an inverter-type centrifugal pump whose capacity can be controlled. The tank 61, the third heat medium pump 42, and the third heat medium flow path 41b of the heat medium heat exchanger 41 are connected by the third heat medium piping 803 to form a third heat medium circuit 93.

It is desirable that the temperature of the third heat medium circulating through the water circuit is stable throughout the year. In particular, it is desirable that the third heat medium has a lower temperature than the outdoor air during cooling operation and a higher temperature than the outdoor air during heating operation. During cooling operation, the heat medium heat exchanger 41 exchanges heat between the first heat medium flowing through the first heat medium flow path 41a and the third heat medium flowing through the third heat medium flow path 41b, thereby cooling the first heat medium. During heating operation, the heat medium heat exchanger 41 exchanges heat between the first heat medium and the third heat medium, thereby heating the first heat medium.

The third heat medium stored in the tank 61 is, for example, well water. Well water contains geothermal heat, which is a renewable energy contained in the earth. In other words, well water is a fluid that contains heat derived from geothermal heat, and the heat medium heat exchanger 41 uses the geothermal heat contained in the well water as a heat source. Note that renewable energy refers to energy that is naturally replenished at a rate faster than it can be used.

Solar heat may be used as the heat source used by the heat medium heat exchanger 41. When solar heat is used as the heat source of the heat medium heat exchanger 41, the third heat medium warmed by a solar panel or the like is stored in the tank 61. In this case, a specific third heat medium may be a calcium chloride solution, a sodium chloride solution, a magnesium chloride solution, a brine containing ethylene glycol, an antifreeze, or water. However, instead of directly circulating well water through the heat medium heat exchanger 41, a heat exchanger that exchanges heat between the third heat medium such as a calcium chloride solution, a sodium chloride solution, a magnesium chloride solution, a brine containing ethylene glycol, an antifreeze, or water and the well water may be provided in the tank 61, and the heat-exchanged third heat medium may be circulated to the third heat medium circuit 93. In addition, a fluid having heat derived from renewable energy other than geothermal heat and solar heat may be used as the fluid flowing through the heat medium heat exchanger 41 described above.

The load device 5 is, for example, an indoor unit installed indoors. The load device 5 receives cold or hot heat from the heat source device 2 via a refrigerant and performs air conditioning in the room. The load device 5 has a load-side heat exchanger 51 and a load-side blower 52.

The load side heat exchanger 51 is, for example, a fin tube type heat exchanger, and exchanges heat between the second heat medium flowing inside the circular or flat tube and the indoor air supplied by the load side blower 52. The load side heat exchanger 51 cools the second heat medium to heat the indoor air during heating operation, and heats the second heat medium to cool the indoor air during cooling operation. If the refrigeration cycle device 1 is, for example, a chiller, the load side heat exchanger 51 may exchange heat between the second heat medium and water to supply cold water. If the refrigeration cycle device 1 is, for example, a water heater, the load side heat exchanger 51 may exchange heat between the second heat medium and water to supply hot water. In the load side heat exchanger 51, the fluid that exchanges heat with the refrigerant corresponds to the "fluid" in this disclosure.

When the refrigeration cycle device 1, which is an air conditioner, performs cooling operation, the air in the air-conditioned space in which the load device 5 is installed is the "cooling target" of this disclosure. Also, when the refrigeration cycle device 1, which is a chiller, supplies cold water, the water flowing through the load side heat exchanger 51 is the "cooling target" of this disclosure. Similarly, when the refrigeration cycle device 1, which is an air conditioner, performs heating operation, the air in the air-conditioned space in which the load device 5 is installed is the "heating target" of this disclosure. Also, when the refrigeration cycle device 1, which is a water heater, supplies hot water, the water flowing through the load side heat exchanger 51 is the "heating target" of this disclosure.

The second heat medium pump 30 of the heat source unit 2, the heat medium flow path 26b of the second heat exchanger 26, and the load side heat exchanger 51 are connected by a second heat medium pipe 802 through which the second heat medium flows, thereby forming a second heat medium circuit 92. The second heat medium may be, for example, a calcium chloride solution, a sodium chloride solution, a magnesium chloride solution, brine containing ethylene glycol, antifreeze, or water. The second heat medium circuit 92 is independent of the first heat medium circuit 91, and the first heat medium flowing through the first heat medium circuit 91 does not flow into the second heat medium circuit 92. For this reason, the second heat medium circuit 92 is not directly thermally affected by the first heat medium circuit 91.

The load side blower 52 is a device that sends indoor air to the load side heat exchanger 51. The load side blower 52 is disposed adjacent to the load side heat exchanger 51. By sending indoor air from the load side blower 52, the efficiency of heat exchange between the refrigerant and the indoor air is improved. As the load side blower 52, a propeller fan, a line flow fan (registered trademark), or a multi-blade centrifugal fan is used. Note that, if the load side heat exchanger 51 exchanges heat between a fluid such as water and a refrigerant, a pump that circulates water or the like may be used instead of the load side blower 52.

The refrigerant temperature sensor 301 is provided in the refrigerant piping 701 between the first heat exchanger 25 and the main throttling device 27. The refrigerant temperature sensor 301 is, for example, a thermistor, and measures the temperature of the refrigerant that flows into the first heat exchanger 25 during cooling operation. The indoor air temperature sensor 501 is provided in the load device 5. The indoor air temperature sensor 501 is, for example, a thermistor, and is a sensor that measures the temperature of the air in the room in which the load device 5 is provided. The refrigerant temperature sensor 301 and the indoor air temperature sensor 501 transmit the measurement results to the control device 100.

The refrigeration cycle device 1 may be provided with a temperature sensor or pressure sensor other than the refrigerant temperature sensor 301 and the indoor air temperature sensor 501. For example, the refrigeration cycle device 1 may be provided with a sensor that detects the temperature of the refrigerant flowing through the refrigerant heat exchanger 23, the temperature of the heat medium flowing through the load side heat exchanger 51, the temperature of the air blown out from the outlet of the load device 5, the temperature of the outdoor air, or the temperature of the well water. Also, instead of the refrigerant temperature sensor 301, a refrigerant pressure sensor that measures the pressure of the refrigerant flowing out of the first heat exchanger 25 during cooling operation may be provided between the first heat exchanger 25 and the secondary throttling device 28.

FIG. 4 is a functional block diagram showing the refrigeration cycle device 1 according to the first embodiment. As shown in FIG. 4, the control device 100 is connected to the compressor 21, the flow path switching device 22, the heat source side blower 24, the main throttling device 27, the sub-throttling device 28, the first heat medium pump 29, the second heat medium pump 30, the third heat medium pump 42, and the load side blower 52 wirelessly or by wire so as to be able to communicate with them. The control device 100 controls the connection direction of the flow path switching device 22 to switch the operation mode. The control device 100 controls the rotation speed of the compressor 21, the rotation speed of the heat source side blower 24, the opening degree of the main throttling device 27, the rotation speed of the first heat medium pump 29, the rotation speed of the second heat medium pump 30, the rotation speed of the third heat medium pump 42, and the rotation speed of the load side blower 52 so that the temperature of the indoor air measured by the indoor air temperature sensor 501 becomes the temperature set by the user.

The control device 100 fully opens the secondary throttling device 28 during heating operation. The control device 100 also adjusts the opening of the secondary throttling device 28 during cooling operation so that the first heat medium circulating through the first heat exchanger 25 does not freeze. Specifically, the lower the temperature of the refrigerant that flows into the first heat exchanger 25 measured by the refrigerant temperature sensor 301, the smaller the opening of the secondary throttling device 28.

The operation of the refrigeration cycle device 1 and the flow of the refrigerant will be described. First, the cooling operation will be described. The control device 100 performs the cooling operation by switching the flow path switching device 22 so that the discharge side of the compressor 21 and the refrigerant heat exchanger 23 are connected. At this time, the refrigerant sucked into the compressor 21 is compressed and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas state refrigerant discharged from the compressor 21 passes through the flow path switching device 22 and flows into the refrigerant heat exchanger 23 acting as a condenser. The refrigerant that flows into the refrigerant heat exchanger 23 is heat exchanged with the outdoor air sent by the refrigerant heat exchanger 23 and condenses, becoming a high-temperature, high-pressure two-phase gas-liquid state. The high-temperature, high-pressure two-phase gas-liquid refrigerant passes through the secondary throttling device 28 and flows into the first heat exchanger 25 acting as a condenser. The refrigerant that flows into the first heat exchanger 25 is heat exchanged with the first heat medium and condenses, becoming a high-pressure liquid state.

The high-pressure liquid refrigerant flows into the main throttle device 27, where it is decompressed and expanded to become a low-temperature, low-pressure, two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant flows into the second heat exchanger 26, which acts as an evaporator. The refrigerant that flows into the second heat exchanger 26 exchanges heat with the second heat medium, causing the liquid phase to evaporate and become gaseous. The low-temperature, low-pressure gaseous refrigerant that flows out of the second heat exchanger 26 passes through the flow switching device 22 and flows back into the compressor 21, where it is compressed and discharged in a high-temperature, high-pressure gaseous state.

The first heat medium circulated through the first heat medium circuit 91 by the first heat medium pump 29 exchanges heat with the third heat medium in the heat medium heat exchanger 41 and is cooled. The cooled first heat medium flows into the first heat exchanger 25. The first heat medium that flows into the first heat exchanger 25 exchanges heat with the high-temperature refrigerant and is heated. At this time, the refrigerant flowing through the first heat exchanger 25 is condensed.

Furthermore, the second heat medium circulated through the second heat medium circuit 92 by the second heat medium pump 30 exchanges heat with the low-temperature refrigerant in the second heat exchanger 26 and is cooled. At this time, the refrigerant flowing through the second heat exchanger 26 is evaporated. The cooled second heat medium flows into the load side heat exchanger 51. The low-temperature second heat medium that has flowed into the load side heat exchanger 51 is heated by exchanging heat with the indoor air sent by the load side blower 52. At this time, the indoor air is cooled and cooling is performed in the room.

Next, the heating operation will be described. The control device 100 performs the heating operation by switching the flow path switching device 22 so that the discharge side of the compressor 21 is connected to the second heat exchanger 26. At this time, the refrigerant sucked into the compressor 21 is compressed and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas state refrigerant discharged from the compressor 21 passes through the flow path switching device 22 and flows into the second heat exchanger 26, which acts as a condenser. The refrigerant that flows into the second heat exchanger 26 exchanges heat with the second heat medium, condenses, and becomes a low-temperature liquid state.

The low-temperature, high-pressure liquid refrigerant is decompressed by the main throttling device 27 to become a low-temperature, low-pressure two-phase gas-liquid refrigerant. The low-temperature, low-pressure two-phase gas-liquid refrigerant flows into the first heat exchanger 25, which acts as an evaporator. The low-temperature, low-pressure two-phase gas-liquid refrigerant that flows into the first heat exchanger 25 is heat exchanged with the first heat medium to become a low-temperature, low-pressure two-phase gas-liquid state and a gas state. The low-temperature, low-pressure two-phase gas-liquid refrigerant and gas state that flows out of the first heat exchanger 25 passes through the secondary throttling device 28 and flows into the refrigerant heat exchanger 23, which acts as an evaporator. The low-temperature, low-pressure two-phase gas-liquid refrigerant and gas state that flows into the refrigerant heat exchanger 23 is heat exchanged with the outdoor air supplied by the refrigerant heat exchanger 23, causing the liquid phase portion to evaporate, becoming a low-pressure gas refrigerant. The low-pressure gas refrigerant that flows out of the refrigerant heat exchanger 23 passes through the flow switching device 22 and flows back into the compressor 21, where it is compressed and discharged in a high-temperature, high-pressure gas state.

The first heat medium circulated through the first heat medium circuit 91 by the first heat medium pump 29 exchanges heat with the third heat medium in the heat medium heat exchanger 41, and is heated. The heated first heat medium flows into the first heat exchanger 25. The first heat medium that has flowed into the first heat exchanger 25 exchanges heat with a low-temperature refrigerant, and is cooled. At this time, part of the refrigerant flowing through the first heat exchanger 25 evaporates.

Furthermore, the second heat medium circulated through the second heat medium circuit 92 by the second heat medium pump 30 exchanges heat with the high-temperature refrigerant in the second heat exchanger 26 and is heated. At this time, the refrigerant flowing through the second heat exchanger 26 is condensed. The heated second heat medium flows into the load side heat exchanger 51. The second heat medium that flows into the load side heat exchanger 51 is cooled by exchanging heat with the indoor air sent by the load side blower 52. At this time, the indoor air is warmed and heating is performed in the room.

As described above, according to the refrigeration cycle device 1 of the first embodiment, the first heat medium circuit 91 and the second heat medium circuit 92 are independent. This prevents the first heat medium and the second heat medium from mixing and wasting heat derived from renewable energy. Therefore, according to the refrigeration cycle device 1, it is possible to prevent a decrease in energy saving performance.

In addition, by having a heat medium heat exchanger 41 that supplies heat derived from renewable energy such as well water to the first heat medium, the rotation speed of the first heat medium pump 29 can be controlled independently of the capacity of the tank 61.

(Modification of the first embodiment)
FIG. 5 is a refrigerant circuit diagram showing a refrigeration cycle apparatus 1A according to a modification of the first embodiment. As shown in FIG. 5, the refrigeration cycle apparatus 1A does not have the auxiliary heat source unit 4 having the heat medium heat exchanger 41 and the third heat medium pump 42 described in the first embodiment. In the modification of the first embodiment, a heat medium such as well water circulates through the first heat medium piping 801 connected to the first heat exchanger 25. In the modification of the first embodiment, the well water corresponds to the first heat medium. In the modification of the first embodiment, the tank 61, the first heat medium pump 29, and the first heat exchanger 25 are connected by the first heat medium piping 801 to form a first heat medium circuit 91. In the modification of the first embodiment, the heat medium heat exchanger 41 is omitted, and the thermal energy of the well water or the like can be directly supplied to the refrigerant circuit 81, thereby improving the energy saving performance.

Embodiment 2.
Fig. 6 is a refrigerant circuit diagram showing a refrigeration cycle apparatus 1B according to embodiment 2. As shown in Fig. 6, the refrigeration cycle apparatus 1B of embodiment 2 differs from the refrigeration cycle apparatus 1 of embodiment 1 in that it has a first bypass pipe 901 and a first bypass valve 31. The following mainly describes the differences from embodiment 1, and a description of the commonalities will be omitted.

The heat source unit 2A has a first bypass pipe 901 and a first bypass valve 31. The first bypass pipe 901 is a pipe that connects the upstream side and downstream side of the refrigerant heat exchanger 23. The first bypass valve 31 is provided in the first bypass pipe 901 and is an electronic expansion valve whose opening is adjustable. The first bypass valve 31 adjusts the flow rate of the refrigerant flowing through the first bypass pipe 901 depending on its opening. The opening of the first bypass valve 31 is controlled by the control device 100.

FIG. 7 is a functional block diagram showing a refrigeration cycle device 1B according to the second embodiment. As shown in FIG. 7, the control device 100 is connected to the first bypass valve 31 by wire or wirelessly so as to be able to communicate with the first bypass valve 31, and controls the opening degree of the first bypass valve 31. The control device 100 opens the first bypass valve 31 when it is determined that the heat exchange capacity of the first heat exchanger 25 is balanced or sufficiently large with respect to the load. Specifically, when the heat exchange capacity of the first heat exchanger 25 is balanced or sufficiently large with respect to the load, the discharge pressure of the compressor 21 decreases, and the rotation speed of the heat source side blower 24 decreases correspondingly. For this reason, the control device 100 opens the first bypass valve 31 when the rotation speed of the heat source side blower 24 is equal to or lower than a threshold value. The opening degree at this time may be fixed, or may be increased as the rotation speed of the heat source side blower 24 decreases. In addition, the control device 100 closes the first bypass valve 31 when the rotation speed of the heat source side blower 24 exceeds the threshold value. In addition, instead of the rotation speed of the heat source side blower 24, when the discharge pressure of the compressor 21 is equal to or lower than the threshold value, the control device 100 opens the first bypass valve 31.

When the first bypass valve 31 is open during cooling operation, a portion of the refrigerant discharged from the compressor 21 and flowing toward the refrigerant heat exchanger 23 flows through the first bypass pipe 901. This allows the condensation temperature in the refrigerant heat exchanger 23 to be lowered. Also, when the first bypass valve 31 is open during heating operation, a portion of the refrigerant flowing out of the first heat exchanger 25 and flowing toward the refrigerant heat exchanger 23 flows through the first bypass pipe 901. This allows the evaporation temperature in the refrigerant heat exchanger 23 to be increased.

Here, a method for controlling the rotation speed of the refrigerant heat exchanger 23 will be described with reference to FIG. 8. FIG. 8 is a flowchart showing the operation of the control device 100 according to the second embodiment. First, the control device 100 determines whether the rotation speed of the heat source side blower 24 is equal to or lower than a threshold value (step S1). If the rotation speed of the heat source side blower 24 is equal to or lower than the threshold value (step S1: YES), the control device 100 opens the first bypass valve 31 (step S2). If the rotation speed of the heat source side blower 24 exceeds the threshold value (step S1: NO), the control device 100 closes the first bypass valve 31 (step S3).

In the refrigeration cycle device 1B of the second embodiment, the first heat medium circuit 91 and the second heat medium circuit 92 are independent, as in the first embodiment. This prevents the first heat medium and the second heat medium from mixing and wasting heat derived from renewable energy. Therefore, the refrigeration cycle device 1B can prevent a decrease in energy saving performance.

In addition, when the first bypass valve 31 is open, the condensation temperature decreases during cooling operation and the evaporation temperature increases during heating operation. This allows the refrigeration cycle device 1B to improve its energy-saving performance.

Embodiment 3.
Fig. 9 is a refrigerant circuit diagram showing a refrigeration cycle apparatus 1C according to embodiment 3. As shown in Fig. 9, the refrigeration cycle apparatus 1C of embodiment 3 differs from the refrigeration cycle apparatus 1 of embodiment 1 in that it has a second bypass pipe 902 and a second bypass valve 32. The following mainly describes the differences from embodiment 1, and a description of the commonalities will be omitted.

The heat source unit 2B has a second bypass pipe 902 and a second bypass valve 32. The second bypass pipe 902 connects the upstream side of the main throttle device 27 and the downstream side of the second heat exchanger 26 in the refrigerant pipe 701 based on the refrigerant flow during cooling operation. The second bypass pipe 902 bypasses the refrigerant flowing toward the second heat exchanger 26 and the main throttle device 27. The second bypass valve 32 is provided in the second bypass pipe 902 and is an electronic expansion valve whose opening is adjustable. The second bypass valve 32 adjusts the flow rate of the refrigerant flowing through the second bypass pipe 902 depending on its opening. The opening of the second bypass valve 32 is controlled by the control device 100.

FIG. 10 is a functional block diagram showing a refrigeration cycle apparatus 1C according to the third embodiment. As shown in FIG. 10, the control device 100 is connected to the second bypass valve 32 so as to be able to communicate with it by wire or wirelessly, and controls the opening degree of the second bypass valve 32. The control device 100 opens the second bypass valve 32 during cooling operation. At this time, the control device 100 detects the degree of subcooling of the refrigerant at the outlet of the first heat exchanger 25 using a refrigerant temperature sensor 301 or the like, and controls the opening degree of the second bypass valve 32 so that the degree of subcooling of the refrigerant is within a target range. The target range of the degree of subcooling of the refrigerant is, for example, 3 to 15° C. The control device 100 increases the opening degree of the second bypass valve 32 when the detected degree of subcooling is greater than the target range, and decreases the opening degree of the second bypass valve 32 when the detected degree of subcooling is less than the target range. When the second bypass valve 32 is open during cooling operation, a portion of the refrigerant flowing toward the second heat exchanger 26 acting as an evaporator flows into the second bypass pipe 902. In addition, the control device 100 closes the second bypass valve 32 during heating operation.

Here, a method for controlling the rotation speed of the refrigerant heat exchanger 23 will be described with reference to FIG. 11. FIG. 11 is a flowchart showing the operation of the control device 100 according to the third embodiment. First, the control device 100 determines whether the operation mode is cooling operation (step S4). If the operation mode is cooling operation (step S4: YES), the control device 100 opens the second bypass valve 32 (step S5). The control device 100 controls the opening degree of the second bypass valve 32 so that the degree of subcooling of the refrigerant falls within a target range. If the operation mode is heating operation (step S4: NO), the control device 100 closes the second bypass valve 32 (step S6).

According to the refrigeration cycle apparatus 1C of the third embodiment, the first heat medium circuit 91 and the second heat medium circuit 92 are independent, as in the first embodiment. This prevents the first heat medium and the second heat medium from mixing and wasting heat derived from renewable energy. Therefore, the refrigeration cycle apparatus 1C can prevent a decrease in energy saving performance.

Furthermore, according to the third embodiment, in cooling operation, the second bypass valve 32 provided in the second bypass pipe 902 is opened so that a part of the refrigerant flowing toward the second heat exchanger 26 acting as an evaporator bypasses the second heat exchanger 26. Therefore, the excess refrigerant generated due to the volume difference between the refrigerant heat exchanger 23 and the second heat exchanger 26 circulates through the refrigerant circuit 81 without passing through the second heat exchanger 26 functioning as an evaporator. Therefore, in cooling operation, the liquid phase ratio of the refrigerant from the downstream side of the first heat exchanger 25 to the compressor 21 is improved compared to the case where the second bypass pipe 902 is not provided. Therefore, the condensation temperature in the refrigerant heat exchanger 23 and the first heat exchanger 25 is lowered, and the energy saving performance is improved.

Embodiment 4.
Fig. 12 is a refrigerant circuit diagram showing a refrigeration cycle apparatus 1D according to embodiment 4. As shown in Fig. 12, the refrigeration cycle apparatus 1D of embodiment 4 has a relay unit 7, and the configuration of the heat source unit 2C is different from that of the refrigeration cycle apparatus 1 of embodiment 1. The following mainly describes the differences from embodiment 1, and a description of the commonalities is omitted.

The heat source unit 2C does not have the first heat exchanger 25, the auxiliary throttling device 28, and the first heat medium pump 29 described in the first embodiment. In the fourth embodiment, the compressor 21, the flow path switching device 22, the refrigerant heat exchanger 23, the main throttling device 27, and the first heat exchanger 25 are connected to form a refrigerant circuit 81. The compressor 21 of the heat source unit 2C of the fourth embodiment corresponds to the "auxiliary compressor" of the present disclosure. The refrigerant heat exchanger 23 of the heat source unit 2C corresponds to the "auxiliary refrigerant heat exchanger" of the present disclosure. The first heat exchanger 25 of the heat source unit 2C corresponds to the "auxiliary heat medium refrigerant heat exchanger" of the present disclosure. The refrigerant circuit 81 corresponds to the "auxiliary refrigerant circuit" of the present disclosure, and the refrigerant circulating in the refrigerant circuit 81 corresponds to the "second refrigerant" of the present disclosure.

The relay unit 7 is a device that relays the transfer of cold or hot heat between the heat source unit 2C and the auxiliary heat source unit 4 and the load device 5. The relay unit 7 has a compressor 71, a flow path switching device 72, a first heat exchanger 73, a second heat exchanger 74, a throttling device 75, and a first heat medium pump 29. The compressor 71, the flow path switching device 72, the first heat exchanger 73, the throttling device 75, and the second heat exchanger 74 are connected by refrigerant piping 702 to form a refrigerant circuit 81. The refrigerant circuit 82 of the fourth embodiment corresponds to the "refrigerant circuit" of this disclosure, and the refrigerant circulating through the refrigerant circuit 82 corresponds to the "first refrigerant" of this disclosure.

The compressor 71 draws in low-pressure gas refrigerant, compresses it, and discharges it as high-pressure gas refrigerant. As the compressor 71, for example, a reciprocating, rotary, scroll, or screw compressor 71 is used.

The flow path switching device 72 switches between cooling operation, in which the first heat exchanger 73 functions as a condenser and the second heat exchanger 74 functions as an evaporator, and heating operation, in which the first heat exchanger 73 functions as an evaporator and the second heat exchanger 74 functions as a condenser. The flow path switching device 72 is, for example, a four-way valve, and is controlled by the control device 100. During cooling operation, the flow path switching device 72 is switched so that the refrigerant discharged from the compressor 71 flows into the first heat exchanger 73. During heating operation, the flow path switching device 72 is switched so that the refrigerant discharged from the compressor 71 flows into the second heat exchanger 74.

The first heat exchanger 73 is, for example, a plate-type heat exchanger, and exchanges heat between the refrigerant flowing through the refrigerant piping 702 and the first heat medium flowing through the first heat medium piping 801. The first heat exchanger 73 is provided in the refrigerant piping 702 between the throttling device 75 and the flow path switching device 72. The first heat exchanger 73 has a refrigerant flow path 73a connected to the refrigerant piping 702 through which the refrigerant flows, and a first heat medium flow path 73b connected to the first heat medium piping 801 through which the first heat medium flows. The first heat exchanger 73 functions as a condenser to condense the refrigerant during cooling operation, and as an evaporator to evaporate the refrigerant during heating operation.

The first heat medium pump 76 of the relay unit 7, the heat medium flow path 73b of the first heat exchanger 73, and the first heat medium flow path 41a of the heat medium heat exchanger 41 of the auxiliary heat source unit 4 are connected by a first heat medium pipe 801 through which the first heat medium flows, thereby forming a first heat medium circuit 91.

The second heat exchanger 74 is, for example, a plate-type heat exchanger, and exchanges heat between the refrigerant flowing through the refrigerant piping 702 and the second heat medium flowing through the second heat medium piping 802. The second heat exchanger 74 is provided in the refrigerant piping 702 between the throttling device 75 and the flow path switching device 72. The second heat exchanger 74 has a refrigerant flow path 74a connected to the refrigerant piping 702 through which the refrigerant flows, and a second heat medium flow path 74b connected to the second heat medium piping 802 through which the second heat medium flows. The second heat exchanger 74 functions as an evaporator to evaporate the refrigerant during cooling operation, and as a condenser to condense the refrigerant during heating operation.

The second heat medium pump 30 of the heat source unit 2C, the heat medium flow path 26b of the second heat exchanger 26, the heat medium flow path 74b of the second heat exchanger 74 of the relay unit 7, and the load side heat exchanger 51 of the load device 5 are connected by a second heat medium pipe 802 through which the second heat medium flows, thereby forming a second heat medium circuit 92. In the fourth embodiment as well, the second heat medium circuit 92 is independent of the first heat medium circuit 91, and the first heat medium flowing through the first heat medium circuit 91 does not flow into the second heat medium circuit 92. For this reason, the second heat medium circuit 92 is not directly thermally affected by the first heat medium circuit 91.

The throttling device 75 is an electronic expansion valve whose opening is adjustable. The throttling device 75 is provided in the refrigerant piping 702 between the first heat exchanger 73 and the second heat exchanger 74. The throttling device 75 reduces the pressure of the refrigerant flowing into the first heat exchanger 73 or the refrigerant flowing out of the first heat exchanger 73, causing it to expand. The opening of the main throttling device 27 is controlled by the control device 100.

The first heat medium pump 76 is provided in the first heat medium pipe 801 and circulates the first heat medium. The first heat medium pump 76 is, for example, an inverter-type centrifugal pump whose capacity can be controlled.

The refrigeration cycle device 1 has a heat medium temperature sensor 401. The heat medium temperature sensor 401 is provided upstream of the heat medium heat exchanger 41 in the heat medium piping 601. The heat medium temperature sensor 401 is, for example, a thermistor, and measures the temperature of the heat medium flowing into the heat medium heat exchanger 41. The heat medium temperature sensor 401 transmits the measurement result to the control device 100.

Figure 13 is a functional block diagram showing a refrigeration cycle apparatus 1D relating to embodiment 4. As shown in Figure 13, the control device 100 is connected to the compressor 21, the flow path switching device 22, the heat source side blower 24, the main throttling device 27, the second heat medium pump 30, the third heat medium pump 42, the load side blower 52, the compressor 71, the flow path switching device 72, the throttling device 75, and the first heat medium pump 76 so as to be able to communicate wirelessly or by wire. The control device 100 controls the connection directions of the flow path switching device 22 and the flow path switching device 72 to switch the operation mode. The control device 100 controls the rotation speed of the compressor 21, the rotation speed of the heat source side blower 24, the opening degree of the main throttling device 27, the rotation speed of the second heat medium pump 30, the rotation speed of the third heat medium pump 42, the rotation speed of the load side blower 52, the rotation speed of the compressor 71, the opening degree of the throttling device 75, and the rotation speed of the first heat medium pump 76 so that the indoor air temperature measured by the indoor air temperature sensor 501 becomes the temperature set by the user.

The control device 100 operates the compressor 71 of the relay unit 7 in priority to the compressor 21 of the heat source unit 2C. When the refrigerant circuit 82 of the relay unit 7 can supply sufficient heat to the load device 5, the control device 100 stops the compressor 21 of the heat source unit 2C. For example, when the temperature of the heat medium measured by the heat medium temperature sensor 401 during cooling operation is equal to or lower than the first threshold, the control device 100 stops the compressor 21 of the heat source unit 2C and drives only the compressor 71 of the relay unit 7. When the temperature of the heat medium exceeds the first threshold, the control device 100 drives the compressor 21 of the heat source unit 2C and the compressor 71 of the relay unit 7. Also, when the temperature of the heat medium measured by the heat medium temperature sensor 401 during heating operation is equal to or higher than the second threshold, the control device 100 stops the compressor 21 of the heat source unit 2C and drives only the compressor 71 of the relay unit 7. When the temperature of the heat medium is less than the second threshold, the compressor 21 of the heat source unit 2C and the compressor 71 of the relay unit 7 are driven. The first threshold is set to a level at which the cold heat supplied to the refrigerant circuit 81 and the second heat medium circuit 92 of the relay unit 7 during cooling operation can process the indoor load. The second threshold is set to a level at which the hot heat supplied to the refrigerant circuit 81 and the second heat medium circuit 92 of the relay unit 7 during heating operation can process the indoor load.

The operation of the refrigeration cycle device 1D and the flow of the refrigerant will be described. Here, the case where both the compressor 21 of the relay unit 7 and the compressor 21 of the heat source unit 2C are driven will be described. First, the cooling operation will be described. The control device 100 performs the cooling operation by switching the flow path switching device 22 so that the discharge side of the compressor 21 of the heat source unit 2C is connected to the refrigerant heat exchanger 23, and switching the flow path switching device 72 so that the discharge side of the compressor 71 of the relay unit 7 is connected to the first heat exchanger 73. At this time, in the refrigerant circuit 81 of the heat source unit 2C, the refrigerant sucked into the compressor 21 is compressed and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas state refrigerant discharged from the compressor 21 passes through the flow path switching device 22 and flows into the refrigerant heat exchanger 23 acting as a condenser. The refrigerant that flows into the refrigerant heat exchanger 23 exchanges heat with the outdoor air sent by the refrigerant heat exchanger 23, condenses, and becomes a high-temperature, high-pressure liquid state.

The high-temperature, high-pressure liquid refrigerant flows into the main throttle device 27, where it is decompressed and expanded to become a low-temperature, low-pressure, two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant flows into the second heat exchanger 26, which acts as an evaporator. The refrigerant that flows into the second heat exchanger 26 exchanges heat with the second heat medium, evaporating the liquid phase and becoming gaseous. The low-temperature, low-pressure gaseous refrigerant that flows out of the second heat exchanger 26 passes through the flow switching device 22 and flows back into the compressor 21, where it is compressed and discharged in a high-temperature, high-pressure gaseous state.

In addition, in the refrigerant circuit 82 of the relay unit 7, the refrigerant sucked into the compressor 71 is compressed and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas refrigerant discharged from the compressor 71 passes through the flow switching device 72 and flows into the first heat exchanger 73, which acts as a condenser. The refrigerant that flows into the first heat exchanger 73 exchanges heat with the first heat medium, condenses, and becomes a high-temperature, high-pressure liquid state.

The high-temperature, high-pressure liquid refrigerant flows into the throttling device 75, where it is decompressed and expanded to become a low-temperature, low-pressure two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant flows into the second heat exchanger 74, which acts as an evaporator. The refrigerant that flows into the second heat exchanger 74 exchanges heat with the second heat medium, evaporating the liquid phase and becoming gaseous. The low-temperature, low-pressure gaseous refrigerant that flows out of the second heat exchanger 74 passes through the flow switching device 72 and flows back into the compressor 71, where it is compressed and discharged in a high-temperature, high-pressure gaseous state.

The first heat medium circulated through the first heat medium circuit 91 by the first heat medium pump 76 exchanges heat with the third heat medium in the heat medium heat exchanger 41 and is cooled. The cooled first heat medium flows into the first heat exchanger 73. The first heat medium that flows into the first heat exchanger 73 exchanges heat with the high-temperature refrigerant and is heated. At this time, the refrigerant flowing through the first heat exchanger 73 is condensed.

Furthermore, the second heat medium circulated through the second heat medium circuit 92 by the second heat medium pump 30 undergoes heat exchange with a low-temperature refrigerant in the second heat exchanger 74 of the relay unit 7, where it is cooled. The cooled second heat medium undergoes heat exchange with a low-temperature refrigerant in the second heat exchanger 26 of the heat source unit 2C, where it is further cooled. The second heat medium cooled in two stages flows into the load side heat exchanger 51. The low-temperature second heat medium that has flowed into the load side heat exchanger 51 is heated by heat exchange with the indoor air sent by the load side blower 52. At this time, the indoor air is cooled, and cooling is performed in the room.

Next, the heating operation will be described. The control device 100 performs the heating operation by switching the flow path switching device 22 so that the discharge side of the compressor 21 of the heat source unit 2C is connected to the second heat exchanger 26, and by switching the flow path switching device 72 so that the discharge side of the compressor 71 of the relay unit 7 is connected to the second heat exchanger 74. At this time, in the refrigerant circuit 81 of the heat source unit 2C, the refrigerant sucked into the compressor 21 is compressed and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas state refrigerant discharged from the compressor 21 passes through the flow path switching device 22 and flows into the second heat exchanger 26 acting as a condenser. The refrigerant that flows into the second heat exchanger 26 exchanges heat with the second heat medium, condenses, and becomes a low-temperature, low-pressure liquid state.

The low-temperature, low-pressure liquid refrigerant is decompressed by the main throttle device 27 to become a low-temperature, low-pressure two-phase gas-liquid refrigerant. The low-temperature, low-pressure two-phase gas-liquid refrigerant that flows out of the main throttle device 27 flows into the refrigerant heat exchanger 23, which acts as an evaporator. The low-temperature, low-pressure two-phase gas-liquid refrigerant that flows into the refrigerant heat exchanger 23 exchanges heat with the outdoor air supplied by the refrigerant heat exchanger 23, evaporating the liquid phase and becoming a low-pressure gas refrigerant. The low-pressure gas refrigerant that flows out of the refrigerant heat exchanger 23 passes through the flow switching device 22 and flows back into the compressor 21, where it is compressed and discharged in a high-temperature, high-pressure gas state.

In addition, in the refrigerant circuit 82 of the relay unit 7, the refrigerant sucked into the compressor 71 is compressed and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas state refrigerant discharged from the compressor 71 passes through the flow path switching device 72 and flows into the second heat exchanger 74, which acts as a condenser. The refrigerant that flows into the second heat exchanger 74 exchanges heat with the second heat medium, condenses, and becomes a high-temperature, high-pressure liquid state.

The high-temperature, high-pressure liquid refrigerant flows into the throttling device 75, where it is decompressed and expanded to become a low-temperature, low-pressure, two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant flows into the first heat exchanger 73, which acts as an evaporator. The refrigerant that flows into the first heat exchanger 73 exchanges heat with the first heat medium, evaporating the liquid phase and becoming gaseous. The low-temperature, low-pressure gaseous refrigerant that flows out of the first heat exchanger 73 passes through the flow switching device 72 and flows back into the compressor 71, where it is compressed and discharged in a high-temperature, high-pressure gaseous state.

The first heat medium circulated through the first heat medium circuit 91 by the first heat medium pump 76 exchanges heat with the third heat medium in the heat medium heat exchanger 41, and is heated. The heated first heat medium flows into the first heat exchanger 73. The first heat medium that flows into the first heat exchanger 73 exchanges heat with a low-temperature refrigerant, and is cooled. At this time, the refrigerant flowing through the first heat exchanger 73 is evaporated.

Furthermore, the second heat medium circulated through the second heat medium circuit 92 by the second heat medium pump 30 is heated by heat exchange with a high-temperature refrigerant in the second heat exchanger 74 of the relay unit 7. The heated second heat medium is further heated by heat exchange with a high-temperature refrigerant in the second heat exchanger 26 of the heat source unit 2C. The second heat medium heated in two stages flows into the load side heat exchanger 51. The second heat medium that flows into the load side heat exchanger 51 is cooled by heat exchange with the indoor air sent by the load side blower 52. At this time, the indoor air is warmed, and heating is performed in the room.

As described above, according to the refrigeration cycle device 1D of embodiment 4, the first heat medium circuit 91 and the second heat medium circuit 92 are independent, as in embodiment 1. This prevents the first heat medium and the second heat medium from mixing and wasting heat derived from renewable energy. Therefore, according to the refrigeration cycle device 1D, it is possible to prevent a decrease in energy saving performance.

Furthermore, according to the fourth embodiment, since the refrigeration cycle device 1D has the refrigerant circuit 81 and the refrigerant circuit 82, it is possible to lower the temperature of the cold heat supplied to the load device 5. Also, it is possible to raise the temperature of the hot heat supplied to the load device 5.

Furthermore, when considering the case where the same amount of cold or hot heat is supplied to the load device 5, the compressor 71 of the relay unit 7 that receives the supply of cold or hot heat from the auxiliary heat source unit 4 is suppressed to have a lower rotation speed than the compressor 21 of the heat source unit 2C. Therefore, by using the refrigerant circuit 82 of the relay unit 7 in preference to the refrigerant circuit 81 of the heat source unit 2C, it is possible to improve energy saving performance.

Embodiment 5.
Fig. 14 is a refrigerant circuit diagram showing a refrigeration cycle apparatus 1E according to embodiment 5. As shown in Fig. 14, the refrigeration cycle apparatus 1E of embodiment 5 has a relay unit 7 and a plurality of load devices 5a and 5b, and is different from the refrigeration cycle apparatus 1E of embodiment 1 in that it performs simultaneous cooling and heating operation. Note that simultaneous cooling and heating operation is an operating state in which one of the load devices 5a and 5b performs cooling operation and the other performs heating operation. The following mainly describes the differences from embodiment 1, and a description of the commonalities is omitted.

The load devices 5a and 5b are, for example, indoor units installed in a room. The load devices 5a and 5b receive cold or hot heat from the heat source device 2 via a refrigerant and perform air conditioning in the room. The load device 5a has a load side heat exchanger 51a, a load side blower 52a, and an outdoor air temperature sensor 501a. The load device 5b has a load side heat exchanger 51b, a load side blower 52b, and an outdoor air temperature sensor 501b. The load devices 5a and 5b and the devices they have are all similar to the load device 5 described in the first embodiment. Therefore, a detailed description of the load devices 5a and 5b will be omitted. Note that when there is no need to distinguish between the load devices 5a and 5b and the devices they have, the suffixes "a" and "b" will be omitted in the description.

The refrigeration cycle device 1E has a first outgoing pipe 804, a first return pipe 805, a second outgoing pipe 806, and a second return pipe 807. The first outgoing pipe 804 is a pipe whose one end is connected to the heat medium flow path 25b of the first heat exchanger 25 and whose other end branches into three directions and connects to the load side heat exchanger 51 and the heat medium heat exchanger 41. The heat medium flows from the first heat exchanger 25 to the load side heat exchanger 51 and the heat medium heat exchanger 41 in the first outgoing pipe 804. The first return pipe 805 is a pipe whose one end is connected to the load side heat exchanger 51 and the heat medium heat exchanger 41 and whose other end branches into three directions and connects to the heat medium flow path 25b of the first heat exchanger 25. The heat medium flows from the load side heat exchanger 51 and the heat medium heat exchanger 41 to the first heat exchanger 25 in the first return pipe 805.

The second outgoing pipe 806 is a pipe having one end connected to the heat medium flow path 26b of the second heat exchanger 26 and the other end branching in three directions to connect to the respective branching parts of the first outgoing pipe 804 corresponding to the load side heat exchanger 51 and the heat medium heat exchanger 41. The heat medium flows from the second heat exchanger 26 to the load side heat exchanger 51 and the heat medium heat exchanger 41 in the second outgoing pipe 806. The second return pipe 807 is a pipe having one end branching in three directions to connect to the respective branching parts of the first return pipe 805 corresponding to the load side heat exchanger 51 and the heat medium heat exchanger 41, and the other end connected to the heat medium flow path 26b of the second heat exchanger 26. The heat medium flows from the load side heat exchanger 51 and the heat medium heat exchanger 41 to the second heat exchanger 26 in the second return pipe 807.

The first heat medium pump 29 is provided in the first return pipe 805 and circulates the heat medium. The second heat medium pump 30 is provided in the second return pipe 807 and circulates the heat medium.

In this way, the first heat exchanger 25, the first heat medium pump 29, the second heat medium pump 30, the second heat exchanger 26, the load side heat exchanger 51, and the heat medium heat exchanger 41 are connected by the first supply pipe 804, the first return pipe 805, the second supply pipe 806, and the second return pipe 807. The heat medium circulates through these. As the heat medium, a calcium chloride solution, a sodium chloride solution, a magnesium chloride solution, a brine containing ethylene glycol, an antifreeze, or water is used. However, by providing the first supply pipe 804, the first return pipe 805, the second supply pipe 806, and the second return pipe 807 with on-off valves (described later), a plurality of independent heat medium circuits are formed so that the heat medium does not flow between the load device 5 and the auxiliary heat source unit 4, which are in different temperature zones.

The relay unit 7 is a device for distributing the heat medium to the load device 5 and the auxiliary heat source unit 4. The relay unit 7 has first on-off valves 201a to 201c, second on-off valves 202a to 202c, third on-off valves 203a to 203c, and fourth on-off valves 204a to 204c. When the on-off valves are not differentiated, they are referred to as on-off valves 200.

The first on-off valve 201a is provided at a position upstream of the position where the other end of the second on-off pipe 806 is connected to the branch portion of the first on-off pipe 804 corresponding to the load side heat exchanger 51a. The first on-off valve 201a is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the first heat exchanger 25 toward the load side heat exchanger 51a, and a closed state that blocks the flow of the heat medium.

The first on-off valve 201b is provided at a position upstream of the position where the other end of the second on-off pipe 806 is connected to the branch portion of the first on-off pipe 804 corresponding to the load side heat exchanger 51b. The first on-off valve 201b is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the first heat exchanger 25 toward the load side heat exchanger 51b, and a closed state that blocks the flow of the heat medium.

The first on-off valve 201c is provided at a position upstream of the position where the other end of the second outgoing pipe 806 is connected to the branch portion of the first outgoing pipe 804 corresponding to the heat medium heat exchanger 41. The first on-off valve 201c is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the first heat exchanger 25 toward the heat medium heat exchanger 41, and a closed state that blocks the flow of the heat medium.

The second on-off valve 202a is provided at a position downstream of the position where one end of the second return pipe 807 is connected to the branch portion of the first return pipe 805 corresponding to the load side heat exchanger 51a. The second on-off valve 202a is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the load side heat exchanger 51a toward the first heat exchanger 25, and a closed state that blocks the flow of the heat medium.

The second on-off valve 202b is provided at a position downstream of the position where one end of the second return pipe 807 is connected to the branch portion of the first return pipe 805 corresponding to the load side heat exchanger 51. The second on-off valve 202b is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the load side heat exchanger 51b toward the first heat exchanger 25, and a closed state that blocks the flow of the heat medium.

The second on-off valve 202c is provided at a position downstream of the position where one end of the second return pipe 807 is connected to the branch portion of the first return pipe 805 corresponding to the heat medium heat exchanger 41. The second on-off valve 202c is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the heat medium heat exchanger 41 toward the first heat exchanger 25, and a closed state that blocks the flow of the heat medium.

The third on-off valve 203a is provided at a branch portion of the second outgoing pipe 806 that corresponds to the load side heat exchanger 51a. The third on-off valve 203a is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the second heat exchanger 26 toward the load side heat exchanger 51a, and a closed state that blocks the flow of the heat medium.

The third on-off valve 203b is provided at a branch portion of the second outgoing pipe 806 that corresponds to the load side heat exchanger 51b. The third on-off valve 203b is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the second heat exchanger 26 toward the load side heat exchanger 51b, and a closed state that blocks the flow of the heat medium.

The third on-off valve 203c is provided at a branch portion of the second outgoing pipe 806 that corresponds to the heat medium heat exchanger 41. The third on-off valve 203c is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the second heat exchanger 26 toward the heat medium heat exchanger 41, and a closed state that blocks the flow of the heat medium.

The fourth on-off valve 204a is provided at a branch portion of the second return pipe 807 that corresponds to the load side heat exchanger 51a. The fourth on-off valve 204a is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the load side heat exchanger 51a toward the second heat exchanger 26, and a closed state that blocks the flow of the heat medium.

The fourth on-off valve 204b is provided at a branch portion of the second return pipe 807 that corresponds to the load side heat exchanger 51b. The fourth on-off valve 204b is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the load side heat exchanger 51b toward the second heat exchanger 26, and a closed state that blocks the flow of the heat medium.

The fourth on-off valve 204c is provided at a branch portion of the second return pipe 807 that corresponds to the heat medium heat exchanger 41. The fourth on-off valve 204c is a valve that can be selectively switched by the control device 100 between an open state that allows the flow of the heat medium from the heat medium heat exchanger 41 toward the second heat exchanger 26, and a closed state that blocks the flow of the heat medium.

FIG. 15 is a functional block diagram showing the refrigeration cycle device 1E according to the first embodiment. As shown in FIG. 15, the control device 100 is connected to the on-off valve 200 wirelessly or by wire so as to be able to communicate with it. Below, the control of the flow path switching device 22 and the on-off valve 200 in each of the cases of full cooling operation in which all the load devices 5 perform cooling operation, full heating operation in which all the load devices 5 perform heating operation, and simultaneous cooling and heating operation will be described.

First, the control of the flow path switching device 22 and the on-off valve 200 during full cooling operation and full heating operation will be described. The control device 100 switches the direction of the flow path switching device 22 to a direction in which the discharge side of the compressor 71 is connected to the refrigerant heat exchanger 23 during full cooling operation, and to a direction in which the discharge side of the compressor 71 is connected to the second heat exchanger 26 during full heating operation.

In addition, during both full cooling operation and full heating operation, the control device 100 closes the first on-off valves 201a and 201b and the second on-off valves 202a and 202b corresponding to the load devices 5a and 5b, and opens the third on-off valves 203a and 203b and the fourth on-off valves 204a and 204b. This blocks the flow of heat medium between the load side heat exchanger 51 and the first heat exchanger 25, and allows the flow of heat medium between the load side heat exchanger 51 and the second heat exchanger 26. In addition, the control device 100 opens the first on-off valve 201c and the second on-off valve 202c corresponding to the auxiliary heat source unit 4, and closes the third on-off valve 203c and the fourth on-off valve 204c. This allows the flow of heat medium between the heat medium heat exchanger 41 and the first heat exchanger 25, and blocks the flow of heat medium between the load side heat exchanger 51 and the second heat exchanger 26.

16 is a refrigerant circuit diagram showing the flow of the refrigerant and the heat medium during full cooling operation and full heating operation in the refrigeration cycle device 1E according to the fifth embodiment. In FIG. 16, the pipes through which the heat medium passes are indicated by thick lines, and the pipes through which the heat medium does not pass are indicated by thin lines. By controlling the open/close state of the on-off valve 200 as described above, as shown in FIG. 16, a heat medium circuit 91A in which the heat medium circulates between the first heat exchanger 25 and the heat medium heat exchanger 41 is formed. In addition, a heat medium circuit 92A in which the heat medium circulates between the second heat exchanger 26, the load side heat exchanger 51a, and the load side heat exchanger 51b is formed. The former heat medium circuit 91A is a heat medium circuit in which the heat medium having heat derived from the renewable energy that has been heat exchanged by the heat medium heat exchanger 41 circulates. Therefore, the former heat medium circuit 91A corresponds to the "first heat medium circuit" of the present disclosure. The heat medium flowing through the heat medium circuit 91A is referred to as the first heat medium. The latter heat medium circuit 92A has a load-side heat exchanger 51a that exchanges heat between the second heat medium and a fluid, and a heat medium flow path 26b of the second heat exchanger 26, and the first heat medium flowing through the heat medium circuit 91A does not flow into the heat medium circuit 92A. Therefore, the heat medium circuit 92A is an independent circuit that is not directly thermally affected by the heat medium circuit 91A. Therefore, the latter heat medium circuit 92A corresponds to the "second heat medium circuit" of this disclosure. The heat medium flowing through the heat medium circuit 92A is referred to as the second heat medium.

When the load devices 5a and 5b constituting the second heat medium circuit perform cooling operation, the first heat exchanger 25 acts as a condenser that condenses the refrigerant, and the second heat exchanger 26 acts as an evaporator that evaporates the refrigerant. When the load devices 5a and 5b constituting the second heat medium circuit perform heating operation, the first heat exchanger 25 acts as an evaporator that evaporates the first refrigerant, and the second heat exchanger 26 acts as a condenser that condenses the refrigerant.

Next, the control of the flow path switching device 22 and the on-off valve 200 during simultaneous cooling and heating operation will be described. Here, simultaneous cooling and heating operation will be described as an example in which the temperature of the third heat medium circulating in the water circuit of the heat medium heat exchanger 41 is lower than the temperature of the outdoor air, and the load device 5a performs cooling operation and the load device 5b performs heating operation. The control device 100 switches the flow path switching device 72 to the same direction as in full cooling operation, that is, the direction in which the discharge side of the compressor 71 and the refrigerant heat exchanger 23 are connected. At this time, the heat medium heat exchanger 41 exchanges heat between the heat medium flowing in the first heat medium flow path 41a and the third heat medium flowing in the third heat medium flow path 41b, and cools the first heat medium. The first heat exchanger 25 functions as a condenser that condenses the refrigerant with the low-temperature first heat medium cooled by the third heat medium flowing in the third heat medium flow path 41b. In addition, the second heat exchanger 26 acts as an evaporator that evaporates the refrigerant.

The control device 100 also closes the first and second on-off valves 201a and 202a corresponding to the load device 5a, and opens the third and fourth on-off valves 203a and 204a. This blocks the flow of heat medium between the load side heat exchanger 51a and the first heat exchanger 25, and allows the flow of heat medium between the load side heat exchanger 51a and the second heat exchanger 26. The control device 100 also opens the first and second on-off valves 201b and 202b corresponding to the load device 5b, and closes the third and fourth on-off valves 203b and 204b. This allows the flow of heat medium between the load side heat exchanger 51b and the first heat exchanger 25, and blocks the flow of heat medium between the load side heat exchanger 51 and the second heat exchanger 26. Furthermore, the control device 100 opens the first on-off valve 201c and the second on-off valve 202c corresponding to the auxiliary heat source unit 4, and closes the third on-off valve 203c and the fourth on-off valve 204c. This allows the flow of heat medium between the heat medium heat exchanger 41 and the first heat exchanger 25, and blocks the flow of heat medium between the load side heat exchanger 51 and the second heat exchanger 26.

17 is a refrigerant circuit diagram showing the flow of the refrigerant and the heat medium during simultaneous cooling and heating operation in the refrigeration cycle device 1E according to the fifth embodiment. In FIG. 17, the pipes through which the heat medium passes are indicated by thick lines, and the pipes through which the heat medium does not pass are indicated by thin lines. By controlling the open/close state of the on-off valve 200 as described above, as shown in FIG. 17, a heat medium circuit 91B is formed in which the heat medium circulates between the first heat exchanger 25, the heat medium heat exchanger 41, and the load side heat exchanger 51b. In addition, a heat medium circuit 92B is formed in which the heat medium circulates between the second heat exchanger 26 and the load side heat exchanger 51a. The former heat medium circuit 91B is a heat medium circuit in which the heat medium having heat derived from the renewable energy that has been heat exchanged by the heat medium heat exchanger 41 circulates. Therefore, the former heat medium circuit 91B corresponds to the "first heat medium circuit" of the present disclosure. The heat medium flowing through the former heat medium circuit is referred to as the first heat medium. The latter heat medium circuit 92B has a load-side heat exchanger 51a that exchanges heat between the second heat medium and a fluid, and a heat medium flow path 26b of the second heat exchanger 26, and the first heat medium flowing through the heat medium circuit 91B does not flow into the heat medium circuit 92B. Therefore, the heat medium circuit 92B is an independent circuit that is not directly thermally affected by the heat medium circuit 91B. Therefore, the heat medium circuit 92B corresponds to the "second heat medium circuit" of this disclosure. The heat medium flowing through the latter heat medium circuit is referred to as the second heat medium.

In this way, in the fifth embodiment, the control of the on-off valve 200 is changed depending on whether the operating state of the refrigeration cycle device 1E is full cooling operation and full heating operation, or simultaneous cooling and heating operation. The combination of open and closed states of the on-off valve 200 determines which heat exchanger and piping constitute the heat medium circuit to function as the "first heat medium circuit" or the "second heat medium circuit".

The operation of the refrigeration cycle device 1E and the flow of the refrigerant and heat medium will be described. The only difference from the first embodiment is that the second heat medium branches off and flows to each of the load devices 5 as shown in FIG. 15 during full cooling operation and full heating operation, and therefore the description will be omitted. For this reason, only the simultaneous cooling and heating operation will be described below using FIG. 17. Here, the simultaneous cooling and heating operation will be described as an example in which the temperature of the third heat medium circulating in the water circuit of the heat medium heat exchanger 41 is lower than the temperature of the outdoor air, and the cooling operation is performed in the load device 5a and the heating operation is performed in the load device 5b. The control device 100 switches the flow path switching device 72 to the same direction as the full cooling operation, that is, the direction in which the discharge side of the compressor 71 and the refrigerant heat exchanger 23 are connected. At this time, the refrigerant sucked into the compressor 71 is compressed and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas state refrigerant discharged from the compressor 71 passes through the flow path switching device 72 and flows into the refrigerant heat exchanger 23, which acts as a condenser. The refrigerant that flows into the refrigerant heat exchanger 23 exchanges heat with the outdoor air sent by the refrigerant heat exchanger 23, condenses, and becomes a high-temperature, high-pressure two-phase gas-liquid state. The high-temperature, high-pressure two-phase gas-liquid refrigerant passes through the secondary throttling device 28 and flows into the first heat exchanger 25, which acts as a condenser. The refrigerant that flows into the first heat exchanger 25 exchanges heat with the first heat medium, condenses, and becomes a high-pressure liquid state.

The high-pressure liquid refrigerant flows into the main throttle device 27, where it is decompressed and expanded to become a low-temperature, low-pressure, two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant flows into the second heat exchanger 26, which acts as an evaporator. The refrigerant that flows into the second heat exchanger 26 exchanges heat with the second heat medium, evaporating the liquid phase and becoming gaseous. The low-temperature, low-pressure gaseous refrigerant that flows out of the second heat exchanger 26 passes through the flow switching device 72 and flows back into the compressor 71, where it is compressed and discharged in a high-temperature, high-pressure gaseous state.

The first heat medium circulated through the heat medium circuit 91B by the first heat medium pump 29 is heated by heat exchange with the high-temperature refrigerant in the first heat exchanger 25. At this time, the refrigerant flowing through the first heat exchanger 25 is condensed. A part of the heated first heat medium is cooled by heat exchange with the third heat medium in the heat medium heat exchanger 41. The remaining part of the heated first heat medium flows into the load side heat exchanger 51b. The high-temperature first heat medium that flows into the load side heat exchanger 51b is cooled by heat exchange with the indoor air sent by the load side blower 52. At this time, the indoor air is warmed, and heating is performed in the room. The low-temperature first heat medium that has passed through the load side heat exchanger 51b is merged with the low-temperature first heat medium that has passed through the heat medium heat exchanger 41, and flows into the first heat exchanger 25 again. Here, the first heat medium that has passed through the load side heat exchanger 51 and the first heat medium that has passed through the heat medium heat exchanger 41 are both low-temperature heat media, so the cold energy supplied from the third heat medium in the heat medium heat exchanger 41 is prevented from being wasted.

Furthermore, the second heat medium circulated through the heat medium circuit 92B by the second heat medium pump 30 exchanges heat with the low-temperature refrigerant in the second heat exchanger 26 and is cooled. At this time, the refrigerant flowing through the second heat exchanger 26 is evaporated. The cooled second heat medium flows into the load side heat exchanger 51. The low-temperature second heat medium that has flowed into the load side heat exchanger 51 is heated by exchanging heat with the indoor air sent by the load side blower 52. At this time, the indoor air is cooled and cooling is performed in the room.

As described above, according to the refrigeration cycle apparatus 1E of the fifth embodiment, during simultaneous heating and cooling operation, the heat medium circuit 91B and the heat medium circuit 92B are independent. This prevents the first heat medium and the second heat medium from mixing and wasting heat derived from renewable energy. Therefore, according to the refrigeration cycle apparatus 1E, it is possible to prevent a decrease in energy saving performance. In particular, according to the example described in the fifth embodiment, it is possible to effectively utilize the cold heat of the third heat medium.

In the above description, the third heat medium circulating through the water circuit of the heat medium heat exchanger 41 is assumed to have a lower temperature than the outdoor air during simultaneous cooling and heating operation. However, the heat medium heat exchanger 41 may be used even when the temperature of the third heat medium circulating through the water circuit of the heat medium heat exchanger 41 is equal to or higher than the temperature of the outdoor air. FIG. 18 is a refrigerant circuit diagram showing the flow of the refrigerant and heat medium during simultaneous cooling and heating operation in the refrigeration cycle device 1E according to the fifth embodiment. When the temperature of the third heat medium circulating through the water circuit of the heat medium heat exchanger 41 is equal to or higher than the temperature of the outdoor air, as shown in FIG. 18, the open/close state of the on-off valve 200 corresponding to the load devices 5a and 5b is reversed from the open/close state of the on-off valve 200 shown in FIG. 17. In addition, the flow path switching device 72 is switched to the same direction as in the full heating operation, that is, the direction in which the discharge side of the compressor 71 and the second heat exchanger 26 are connected as shown by the dashed line in FIG. 18.

At this time, a heat medium circuit 91C is formed in which the heat medium circulates between the first heat exchanger 25, the heat medium heat exchanger 41, and the load side heat exchanger 51a. Also, a heat medium circuit 92C is formed in which the heat medium circulates between the second heat exchanger 26 and the load side heat exchanger 51b. The heat medium circuit 91C corresponds to the "first heat medium circuit" of the present disclosure, and the heat medium circuit 92C corresponds to the "second heat medium circuit" of the present disclosure. The first heat exchanger 25 functions as an evaporator that evaporates the refrigerant using the high-temperature first heat medium heated by the third heat medium flowing through the third heat medium flow path 41b and the high-temperature first heat medium heated by passing through the load side heat exchanger 51a. The second heat exchanger 26 functions as a condenser that evaporates the refrigerant using the low-temperature second heat medium cooled by passing through the load side heat exchanger 51b. In this case, the heat of the third heat medium can be effectively utilized. Furthermore, when simply switching between cooling and heating operation in the load devices 5a and 5b, the open/closed state of the corresponding on-off valve 200 can be reversed.

The above is an explanation of the embodiments, but the present disclosure is not limited to the above embodiments, and various modifications and combinations are possible without departing from the spirit of the present disclosure. The second bypass piping 902 and the second bypass valve 32 described in the second embodiment may be applied to the refrigeration cycle device 1 described in the third embodiment. Also, in the refrigeration cycle devices of the second to fifth embodiments, the heat medium heat exchanger 41 may be omitted, and well water or the like may be circulated directly through the first heat exchanger, as described in the modified example of the first embodiment.

Furthermore, the first heat medium pumps 29 and 76, the second heat medium pump 30, and the third heat medium pump 42 may be installed at any position as long as they can circulate the heat medium flowing through the heat medium pipes described in the embodiment. For example, the first heat medium pumps 29 and 76 may be installed outside the heat source unit and the relay unit.

1, 1A, 1B, 1C, 1D, 1E refrigeration cycle device, 2, 2A, 2B, 2C heat source unit, 4 auxiliary heat source unit, 5 load device, 7 relay unit, 21 compressor, 22 flow path switching device, 23 refrigerant heat exchanger, 24 heat source side blower, 25 first heat exchanger, 25a refrigerant flow path, 25b heat medium flow path, 26 second heat exchanger, 26a refrigerant flow path, 26b heat medium flow path, 27 main throttle device, 28 secondary throttle device, 29 first heat medium pump, 30 second heat medium pump, 31 first bypass valve, 32 second bypass valve, 41 heat medium heat exchanger, 41a first heat medium flow path, 41b third heat medium flow path, 42 third heat medium pump, 51, 51a, 51b load side heat exchanger, 52, 52a, 52b load side blower, 61 tank, 71 compressor, 72 flow path switching device, 73 first heat exchanger, 73a refrigerant flow path, 73b heat medium flow path, 74 second heat exchanger, 74a refrigerant flow path, 74b heat medium flow path, 75 throttling device, 76 first heat medium pump, 81 refrigerant circuit, 8 2 Refrigerant circuit, 91 First heat medium circuit, 91A, 92A, 91B, 92B, 91C, 92C Heat medium circuit, 92 Second heat medium circuit, 93 Third heat medium circuit, 100 Control device, 101 Processing circuit, 102 Processor, 103 Memory, 104 Bus, 200 Opening/closing valve, 201a First opening/closing valve, 202a Second opening/closing valve, 203a Third opening/closing valve, 204a Fourth opening/closing valve, 201b First opening/closing valve, 202b Second opening/closing valve, 203b Third opening/closing valve, 204b Fourth opening/closing valve, 201c first on-off valve, 202c second on-off valve, 203c third on-off valve, 204c fourth on-off valve, 301 refrigerant temperature sensor, 401 heat medium temperature sensor, 501, 501a, 501b indoor air temperature sensor, 701 refrigerant piping, 702 refrigerant piping, 801 first heat medium piping, 802 second heat medium piping, 803 third heat medium piping, 804 first outgoing pipe, 805 first return pipe, 806 second outgoing pipe, 807 second return pipe, 901 first bypass piping, 902 second bypass piping.

Claims (8)

a first heat medium circuit in which a first heat medium having heat derived from renewable energy circulates;
a refrigerant circuit including a compressor that compresses a first refrigerant, a first heat exchanger that performs heat exchange between the first heat medium and the first refrigerant, and a refrigerant flow path through which the first refrigerant flows in a second heat exchanger that performs heat exchange between a second heat medium and the first refrigerant;
a second heat medium circuit which is independent of the first heat medium circuit and has a load-side heat exchanger which performs heat exchange between the second heat medium and a fluid which is an object to be heated or cooled, and a heat medium flow path through which the second heat medium of the second heat exchanger flows. The refrigeration cycle apparatus according to claim 1 , wherein the refrigerant circuit further includes a refrigerant heat exchanger that exchanges heat between the first refrigerant and outdoor air. a heat source side blower for supplying the outdoor air to the refrigerant heat exchanger;
a first bypass pipe connecting an upstream side and a downstream side of the refrigerant heat exchanger;
a first bypass valve provided in the first bypass pipe and configured to adjust a flow rate of the first refrigerant;
A control device that controls the first bypass valve,
The control device includes:
When the rotation speed of the heat source side blower is equal to or lower than a threshold value, the first bypass valve is opened;
The refrigeration cycle apparatus according to claim 2 , wherein the first bypass valve is closed when a rotation speed of the heat source side blower is higher than the threshold value. a main throttle device that reduces the pressure of the first refrigerant;
a second bypass pipe connecting an upstream side of the main throttle device and a downstream side of the second heat exchanger with respect to a flow of the first refrigerant when cooling the fluid;
a second bypass valve provided in the second bypass pipe and configured to adjust a flow rate of the first refrigerant;
A control device that controls the second bypass valve,
The control device includes:
When the fluid is heated, the second bypass valve is opened;
The refrigeration cycle apparatus according to claim 2 or 3, wherein when the fluid is cooled, the second bypass valve is closed. 2. The refrigeration cycle apparatus according to claim 1, further comprising an auxiliary refrigerant circuit including: an auxiliary compressor that compresses a second refrigerant different from the first refrigerant; an auxiliary refrigerant heat exchanger that performs heat exchange between the second refrigerant and outdoor air; and an auxiliary heat medium refrigerant heat exchanger that performs heat exchange between the second refrigerant and the second heat medium. The refrigeration cycle apparatus according to any one of claims 1 to 5, further comprising an auxiliary heat source unit having a heat medium heat exchanger that supplies heat derived from the renewable energy to the first heat medium by heat exchange between well water and the first heat medium. A load-side heat exchanger for cooling the fluid and a load-side heat exchanger for heating the fluid,
The first heat medium circuit is connected to one of a plurality of load side heat exchangers, the heat medium heat exchanger, and a heat medium flow path of the first heat exchanger,
The refrigeration cycle apparatus according to claim 6 , wherein the second heat medium circuit is formed by connecting the other of the plurality of load side heat exchangers to a heat medium flow path of the second heat exchanger. When the load-side heat exchanger constituting the second heat medium circuit cools the fluid, the first heat exchanger acts as a condenser that condenses the first refrigerant, and the second heat exchanger acts as an evaporator that evaporates the first refrigerant,
8. The refrigeration cycle device according to claim 1, wherein when the load side heat exchanger constituting the second heat medium circuit heats the fluid, the first heat exchanger acts as an evaporator that evaporates the first refrigerant, and the second heat exchanger acts as a condenser that condenses the first refrigerant.

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