Refrigeration cycle device

Abstract

A refrigeration cycle device (1) comprises: a refrigerant circuit (7) through which a refrigerant circulates; an indoor unit (3) that cools or heats the inside of a room using the heat of the refrigerant; a water circuit (6) through which water circulates; a water-refrigerant heat exchange unit (15) that exchanges heat between the refrigerant and the water so that the water is heated by the refrigerant radiating heat; and air heat exchangers (33) (38) that, when the water-refrigerant heat exchange unit (15) heats the water while the indoor unit (3) cools or heats the inside of the room, further radiate heat from the refrigerant that has undergone the heat radiation by the water-refrigerant heat exchange unit (15).

Description

Refrigeration cycle apparatus

[0001] The technology of the present disclosure relates to a refrigeration cycle apparatus.

[0002] A refrigeration cycle apparatus is known that is capable of supplying hot water while performing cooling and heating, that is, while performing either one of cooling operation or heating operation (Japanese Patent No. 7438397). Such a refrigeration cycle apparatus heats water by using the condensation heat of a refrigerant used for cooling and heating, and can reduce power consumption compared to other refrigeration cycle apparatuses that perform cooling / heating and hot water supply separately.

[0003] Japanese Patent No. 7438397

[0004] In such a refrigeration cycle apparatus, when heating water to a high temperature, it is necessary to increase the condensation temperature of the refrigerant, and it is necessary to increase the condensation pressure of the refrigerant. However, when supplying hot water while performing cooling, the compression ratio of a compressor that compresses the refrigerant increases, which may affect the reliability of the compressor. Further, when supplying hot water while performing heating, depending on the operating condition of heating, the condensation pressure may not rise to a predetermined pressure required for heating water to a high temperature. In such a refrigeration cycle apparatus, it is conceivable to use a heater when heating water to a high temperature, but in this case, there is a problem that power consumption increases.

[0005] The disclosed technology has been made in view of this point, and an object of the present invention is to provide a refrigeration cycle apparatus that heats water to a high temperature while achieving both ensuring reliability and reducing power consumption.

[0006] A refrigeration cycle apparatus according to an aspect of the present disclosure includes: a refrigerant circuit in which a refrigerant circulates; an indoor unit that cools and heats a room using heat of the refrigerant; a water circuit in which water circulates; a water heat exchanger that exchanges heat between the refrigerant and the water such that the water is heated by heat radiation of the refrigerant; and an air heat exchanger that further radiates heat from the refrigerant after heat radiation radiated in the water heat exchanger when the water heat exchanger heats the water while the indoor unit cools and heats the room.

[0007] The disclosed refrigeration cycle device can heat water to a high temperature while ensuring reliability and reducing power consumption.

[0008] Figure 1 is a circuit diagram showing the refrigeration cycle device of Example 1. Figure 2 is a block diagram of the control device. Figure 3 is a Mollier diagram showing the state change of the refrigerant in the refrigerant circuit when cooling sensible heat hot water supply operation is performed. Figure 4 is a Mollier diagram showing the state change of the refrigerant in the refrigerant circuit when cooling total heat hot water supply operation is performed. Figure 5 is a Mollier diagram showing the state change of the refrigerant in the refrigerant circuit when heating sensible heat hot water supply operation is performed. Figure 6 is a Mollier diagram showing the state change of the refrigerant in the refrigerant circuit when heating total heat hot water supply operation is performed. Figure 7 is a circuit diagram showing the refrigeration cycle device of Example 2.

[0009] The refrigeration cycle apparatus according to the embodiments disclosed herein will be described in detail below with reference to the drawings. However, the technology of this disclosure is not limited by the following description. Furthermore, the same reference numerals are used for identical components, and redundant explanations are omitted.

[0010] The refrigeration cycle device 1 of Embodiment 1 comprises an outdoor unit 2, an indoor unit 3, and a hot water supply unit 5, as shown in Figure 1. Figure 1 is a circuit diagram showing the refrigeration cycle device 1 of Embodiment 1. The outdoor unit 2 is installed outside the room that is heated and cooled by the refrigeration cycle device 1. The indoor unit 3 is installed inside the room that is heated and cooled by the refrigeration cycle device 1. The refrigeration cycle device 1 further comprises a water circuit 6 and a refrigerant circuit 7. The water circuit 6 comprises a hot water supply tank 11, a pump 12 (flow rate control means), a switching valve 14, a first water-refrigerant heat exchanger 15 (water heat exchange section), a second water-refrigerant heat exchanger 16 (other water heat exchange section), a water confluence section 17, and a hot water tank inlet switching valve 18.

[0011] The hot water tank 11 is located inside the hot water supply unit 5. The hot water tank 11 stores water that circulates in the water circuit 6. The hot water tank 11 has an outlet 21, a first inlet 22, a second inlet 23, a hot water outlet 24, and a cold water outlet 25. The hot water supply unit 5 is equipped with a cold water connection port 26, a pressure reducing valve 27, a hot water mixing valve 28, and a hot water connection port 29. The outlet 21 and the cold water outlet 25 are located at the bottom of the hot water tank 11. The lower space inside the hot water tank 11 is connected to the pump 12 via the outlet 21 and to the pressure reducing valve 27 via the cold water outlet 25. The first inlet 22 and the hot water outlet 24 are located at the top of the hot water tank 11. The upper space inside the hot water tank 11 is connected to the hot water tank inlet switching valve 18 via the first inlet 22 and to the hot water mixing valve 28 via the hot water outlet 24. The second inlet 23 is located below the first inlet 22 and is connected to the hot water tank inlet switching valve 18.

[0012] The pump 12 is located inside the hot water supply unit 5. The pump 12 is connected to the switching valve 14. The pump 12 comprises a main body and a rotating body. The rotating body rotates relative to the main body, supplying water stored in the lower space of the hot water supply tank 11 to the switching valve 14 via the outlet 21, and circulating the water in the water circuit 6. The flow rate of water supplied by the pump 12 to the switching valve 14 per unit time increases as the pump rotation speed, which indicates the number of rotations of the rotating body relative to the main body per unit time, increases. The power consumed by the pump 12 also increases as the pump rotation speed increases.

[0013] The switching valve 14 is located inside the outdoor unit 2. The switching valve 14 is connected to the first water-refrigerant heat exchanger 15 and the second water-refrigerant heat exchanger 16. The first water-refrigerant heat exchanger 15 is located inside the outdoor unit 2. The first water-refrigerant heat exchanger 15 is connected to the water confluence section 17. The first water-refrigerant heat exchanger 15 exchanges heat between the refrigerant that flows into the first water-refrigerant heat exchanger 15 via the refrigerant circuit 7 and the low-temperature water that flows into the first water-refrigerant heat exchanger 15 via the water circuit 6. The second water-refrigerant heat exchanger 16 is located inside the outdoor unit 2. The second water-refrigerant heat exchanger 16 is connected to the water confluence section 17. The second water-refrigerant heat exchanger 16 exchanges heat between the refrigerant that flows into the second water-refrigerant heat exchanger 16 via the refrigerant circuit 7 and the low-temperature water that flows into the second water-refrigerant heat exchanger 16 via the water circuit 6. The heat transfer area of ​​the first water-refrigerant heat exchanger 15 is formed to be smaller than the heat transfer area of ​​the second water-refrigerant heat exchanger 16.

[0014] The water confluence section 17 is located inside the outdoor unit 2. The water confluence section 17 is connected to the hot water tank inlet switching valve 18. The hot water tank inlet switching valve 18 switches the flow path of the water circuit 6 so that the water confluence section 17 is connected to either the first inlet 22 or the second inlet 23.

[0015] The water supply connection port 26 is connected to the piping connected to the water supply system and is connected to the pressure reducing valve 27. The hot water mixing valve 28 is connected to the pressure reducing valve 27 and is connected to the hot water connection port 29. The hot water connection port 29 is connected to the piping connected to the faucet. An example of a faucet is a tap operated by the user.

[0016] The refrigerant circuit 7 comprises a compressor 31, a refrigerant circuit switching valve 32, an outdoor heat exchanger 33 (air heat exchanger, heat source side heat exchanger), an outdoor expansion valve 34, a receiver 35, a boiling expansion valve 36, an indoor expansion valve 37, and an indoor heat exchanger 38 (air heat exchanger, utilization side heat exchanger). The compressor 31 is located inside the outdoor unit 2. The compressor 31 comprises an intake pipe 41 and a discharge pipe 42. The compressor 31 compresses the refrigerant drawn into the compressor 31 via the intake pipe 41, discharges the compressed refrigerant through the discharge pipe 42, and circulates the refrigerant in the refrigerant circuit 7.

[0017] The refrigerant circuit switching valve 32 is located inside the outdoor unit 2. The refrigerant circuit switching valve 32 includes a first solenoid valve 43, a second solenoid valve 44, a refrigerant branching section 45, a third solenoid valve 46, a fourth solenoid valve 47, a first three-way valve 48, and a second three-way valve 49. The discharge pipe 42 is connected to the first solenoid valve 43 and the second solenoid valve 44. The first solenoid valve 43 is connected to the first water-refrigerant heat exchanger 15. The first solenoid valve 43 is opened so that the discharge pipe 42 is connected to the first water-refrigerant heat exchanger 15 via the first solenoid valve 43, or closed so that the discharge pipe 42 is not connected to the first water-refrigerant heat exchanger 15 via the first solenoid valve 43.

[0018] The second solenoid valve 44 is connected to the refrigerant branching section 45. The second solenoid valve 44 can be opened so that the discharge pipe 42 is connected to the refrigerant branching section 45 via the second solenoid valve 44, or closed so that the discharge pipe 42 is not connected to the refrigerant branching section 45 via the second solenoid valve 44. The refrigerant branching section 45 is connected to the first water-refrigerant heat exchanger 15 and is connected to the third solenoid valve 46, the first three-way valve 48, and the second three-way valve 49.

[0019] The third solenoid valve 46 is connected to the second water-refrigerant heat exchanger 16. The third solenoid valve 46 can be opened so that the refrigerant branching section 45 is connected to the second water-refrigerant heat exchanger 16 via the third solenoid valve 46, or closed so that the refrigerant branching section 45 is not connected to the second water-refrigerant heat exchanger 16 via the third solenoid valve 46.

[0020] The fourth solenoid valve 47 is connected in the middle of the refrigerant piping between the third solenoid valve 46 and the second water refrigerant heat exchanger 16, and is connected to the suction pipe 41. The fourth solenoid valve 47 is opened so that the second water refrigerant heat exchanger 16 is connected to the suction pipe 41 via the fourth solenoid valve 47, or closed so that the second water refrigerant heat exchanger 16 is not connected to the suction pipe 41 via the fourth solenoid valve 47.

[0021] The first three-way valve 48 is connected to the outdoor heat exchanger 33, the suction pipe 41, and the refrigerant branching section 45. The first three-way valve 48 switches the flow path of the refrigerant circuit 7 so that the refrigerant branching section 45 is connected to the outdoor heat exchanger 33 via the first three-way valve 48, or so that the outdoor heat exchanger 33 is connected to the suction pipe 41 via the first three-way valve 48. The second three-way valve 49 is connected to the indoor heat exchanger 38, the suction pipe 41, and the refrigerant branching section 45. The second three-way valve 49 switches the flow path of the refrigerant circuit 7 so that the refrigerant branching section 45 is connected to the indoor heat exchanger 38 via the second three-way valve 49, or so that the indoor heat exchanger 38 is connected to the suction pipe 41 via the second three-way valve 49.

[0022] The refrigerant circuit switching valve 32 switches the refrigerant circuit 7 to one of the following cycles: cooling sensible heat hot water supply cycle, cooling total heat hot water supply cycle, heating sensible heat hot water supply cycle, heating total heat hot water supply cycle, cooling only cycle, heating only cycle, and hot water only cycle. [Cooling sensible heat hot water supply cycle] When the refrigerant circuit 7 is switched to the cooling sensible heat hot water supply cycle, the first solenoid valve 43 is opened and the second solenoid valve 44 is closed, so the discharge pipe 42 is not connected to the refrigerant branching section 45 but is connected to the first water refrigerant heat exchanger 15 via the first solenoid valve 43. Also, when the third solenoid valve 46 is closed, the refrigerant branching section 45 is not connected to the second water refrigerant heat exchanger 16 via the third solenoid valve 46. Also, when the fourth solenoid valve 47 is opened, the second water refrigerant heat exchanger 16 is connected to the suction pipe 41 via the fourth solenoid valve 47. Furthermore, the first three-way valve 48 is switched so that the refrigerant branching section 45 and the outdoor heat exchanger 33 are not connected to the suction pipe 41, and the refrigerant branching section 45 is connected to the outdoor heat exchanger 33 via the first three-way valve 48. Also, the second three-way valve 49 is switched so that the refrigerant branching section 45 is not connected to the indoor heat exchanger 38 and the suction pipe 41, and the indoor heat exchanger 38 is connected to the suction pipe 41 via the second three-way valve 49.

[0023] [Cooling Total Heat Supply Cycle] When the refrigerant circuit 7 is switched to the cooling total heat supply cycle, the first solenoid valve 43 is closed and the second solenoid valve 44 is opened, so that the discharge pipe 42 is not connected to the first water refrigerant heat exchanger 15 but is connected to the refrigerant branch section 45 via the second solenoid valve 44. Also, when the third solenoid valve 46 is opened, the refrigerant branch section 45 is connected to the second water refrigerant heat exchanger 16 via the third solenoid valve 46. Also, when the fourth solenoid valve 47 is closed, the second water refrigerant heat exchanger 16 is not connected to the suction pipe 41. In addition, the first three-way valve 48 is switched so that the refrigerant branch section 45 is not connected to the outdoor heat exchanger 33 and the suction pipe 41, and the outdoor heat exchanger 33 is connected to the suction pipe 41 via the first three-way valve 48. Furthermore, the second three-way valve 49 is switched so that the refrigerant branching section 45 is not connected to the indoor heat exchanger 38 and the suction pipe 41, and the indoor heat exchanger 38 is connected to the suction pipe 41 via the second three-way valve 49.

[0024] [Heating Sensible Heat Hot Water Supply Cycle] When the refrigerant circuit 7 is switched to the heating sensible heat hot water supply cycle, the first solenoid valve 43 is opened and the second solenoid valve 44 is closed, so that the discharge pipe 42 is not connected to the refrigerant branching section 45 but is connected to the first water-refrigerant heat exchanger 15 via the first solenoid valve 43. Also, when the third solenoid valve 46 is closed, the refrigerant branching section 45 is not connected to the second water-refrigerant heat exchanger 16. Also, when the fourth solenoid valve 47 is opened, the second water-refrigerant heat exchanger 16 is connected to the suction pipe 41 via the fourth solenoid valve 47. In addition, the first three-way valve 48 is switched so that the refrigerant branching section 45 is not connected to the outdoor heat exchanger 33 and the suction pipe 41, and the outdoor heat exchanger 33 is connected to the suction pipe 41 via the first three-way valve 48. Furthermore, the second three-way valve 49 is switched so that the refrigerant branching section 45 and the indoor heat exchanger 38 are not connected to the suction pipe 41, and the refrigerant branching section 45 is connected to the indoor heat exchanger 38 via the second three-way valve 49.

[0025] [Heating Total Heat Supply Cycle] When the refrigerant circuit 7 is switched to the heating total heat supply cycle, the first solenoid valve 43 is closed and the second solenoid valve 44 is opened, so that the discharge pipe 42 is not connected to the first water-refrigerant heat exchanger 15 but is connected to the refrigerant branch section 45 via the second solenoid valve 44. Also, when the third solenoid valve 46 is opened, the refrigerant branch section 45 is connected to the second water-refrigerant heat exchanger 16 via the third solenoid valve 46. Also, when the fourth solenoid valve 47 is closed, the second water-refrigerant heat exchanger 16 is not connected to the suction pipe 41. In addition, the first three-way valve 48 is switched so that the refrigerant branch section 45 is not connected to the outdoor heat exchanger 33 and the suction pipe 41, and the outdoor heat exchanger 33 is connected to the suction pipe 41 via the first three-way valve 48. Furthermore, the second three-way valve 49 is switched so that the refrigerant branching section 45 and the indoor heat exchanger 38 are not connected to the suction pipe 41, and the refrigerant branching section 45 is connected to the indoor heat exchanger 38 via the second three-way valve 49.

[0026] [Cooling-only cycle] When the refrigerant circuit 7 is switched to a cooling-only cycle, the first solenoid valve 43 is closed and the second solenoid valve 44 is opened, so that the discharge pipe 42 is not connected to the first water refrigerant heat exchanger 15 but is connected to the refrigerant branch section 45 via the second solenoid valve 44. Also, when the third solenoid valve 46 is closed, the refrigerant branch section 45 is not connected to the second water refrigerant heat exchanger 16. Also, when the fourth solenoid valve 47 is opened, the second water refrigerant heat exchanger 16 is connected to the suction pipe 41 via the fourth solenoid valve 47. In addition, the first three-way valve 48 is switched so that the refrigerant branch section 45 and the outdoor heat exchanger 33 are not connected to the suction pipe 41, and the refrigerant branch section 45 is connected to the outdoor heat exchanger 33 via the first three-way valve 48. Furthermore, the second three-way valve 49 is switched so that the refrigerant branching section 45 is not connected to the indoor heat exchanger 38 and the suction pipe 41, and the indoor heat exchanger 38 is connected to the suction pipe 41 via the second three-way valve 49.

[0027] [Heating-only cycle] When the refrigerant circuit 7 is switched to a heating-only cycle, the first solenoid valve 43 is closed and the second solenoid valve 44 is opened, so that the discharge pipe 42 is not connected to the first water-refrigerant heat exchanger 15 but is connected to the refrigerant branch section 45 via the second solenoid valve 44. Also, when the third solenoid valve 46 is closed, the refrigerant branch section 45 is not connected to the second water-refrigerant heat exchanger 16. Also, when the fourth solenoid valve 47 is opened, the second water-refrigerant heat exchanger 16 is connected to the suction pipe 41 via the fourth solenoid valve 47. In addition, the first three-way valve 48 is switched so that the refrigerant branch section 45 is not connected to the outdoor heat exchanger 33 and the suction pipe 41, and the outdoor heat exchanger 33 is connected to the suction pipe 41 via the first three-way valve 48. Furthermore, the second three-way valve 49 is switched so that the refrigerant branching section 45 and the indoor heat exchanger 38 are not connected to the suction pipe 41, and the refrigerant branching section 45 is connected to the indoor heat exchanger 38 via the second three-way valve 49.

[0028] [Hot water supply only cycle] When the refrigerant circuit 7 is switched to the hot water supply only cycle, the first solenoid valve 43 is closed and the second solenoid valve 44 is opened, so that the discharge pipe 42 is not connected to the first water-refrigerant heat exchanger 15 but is connected to the refrigerant branch section 45 via the second solenoid valve 44. Also, when the third solenoid valve 46 is opened, the refrigerant branch section 45 is connected to the second water-refrigerant heat exchanger 16 via the third solenoid valve 46. Also, when the fourth solenoid valve 47 is closed, the second water-refrigerant heat exchanger 16 is not connected to the suction pipe 41. In addition, the first three-way valve 48 is switched so that the refrigerant branch section 45 is not connected to the outdoor heat exchanger 33 and the suction pipe 41, and the outdoor heat exchanger 33 is connected to the suction pipe 41 via the first three-way valve 48. Furthermore, the second three-way valve 49 is switched so that the refrigerant branching section 45 is not connected to the indoor heat exchanger 38 and the suction pipe 41, and the indoor heat exchanger 38 is connected to the suction pipe 41 via the second three-way valve 49.

[0029] The outdoor heat exchanger 33 is located inside the outdoor unit 2. The outdoor heat exchanger 33 is connected to the outdoor expansion valve 34. The outdoor expansion valve 34 is located inside the outdoor unit 2. The outdoor expansion valve 34 is connected to the receiver 35. The receiver 35 is located inside the outdoor unit 2. The receiver 35 is connected to the boiling expansion valve 36 and the indoor expansion valve 37.

[0030] The boiling expansion valve 36 is located inside the outdoor unit 2 and is connected to the second water refrigerant heat exchanger 16. The indoor expansion valve 37 is located inside the outdoor unit 2 and is connected to the indoor heat exchanger 38. The indoor heat exchanger 38 is located in the indoor unit 3.

[0031] The outdoor unit 2 is equipped with an outdoor fan 51. The outdoor fan 51 passes outside air through the outdoor heat exchanger 33. The indoor unit 3 passes the air from the room in which the indoor unit 3 is installed through the indoor heat exchanger 38, and blows the air that has passed through the indoor heat exchanger 38 back into the room.

[0032] The refrigeration cycle device 1 further includes an inlet water temperature sensor 52, an outlet water temperature sensor 53, a discharge pressure sensor 54 (superheat sensor), and a water heat exchanger outlet temperature sensor 55 (superheat sensor). The inlet water temperature sensor 52 is located inside the hot water supply unit 5. The inlet water temperature sensor 52 measures the temperature of the water flowing out from the outlet 21 of the hot water supply tank 11 and into the switching valve 14 as the inlet water temperature. The outlet water temperature sensor 53 is located inside the hot water supply unit 5. The outlet water temperature sensor 53 measures the temperature of the water flowing out from the water confluence section 17 and into the hot water supply tank inlet switching valve 18 as the outlet water temperature.

[0033] The discharge pressure sensor 54 is located inside the outdoor unit 2. The discharge pressure sensor 54 measures the pressure of the refrigerant discharged from the compressor 31 to the discharge pipe 42. The water heat exchanger outlet temperature sensor 55 is located inside the outdoor unit 2. The water heat exchanger outlet temperature sensor 55 measures the temperature of the refrigerant flowing out of the first water-refrigerant heat exchanger 15 and into the refrigerant branch section 45.

[0034] The refrigeration cycle device 1 further includes a control device 61, as shown in Figure 2. Figure 2 is a block diagram of the control device 61. The control device 61 is a computer and includes a storage device 62 and a CPU 63 (Central Processing Unit). The storage device 62 stores computer programs installed in the control device 61 and stores information used by the CPU 63. The CPU 63 executes computer programs installed in the control device 61. The control device 61 is connected to the pump 12, the hot water tank inlet switching valve 18, and the refrigerant circuit switching valve 32, and is also connected to the inlet water temperature sensor 52, the outlet water temperature sensor 53, the discharge pressure sensor 54, and the water heat exchanger outlet temperature sensor 55.

[0035] The control device 61 performs multiple functions when a computer program is executed. The control device 61 includes a refrigerant circuit switching unit 64, a water circuit switching unit 65, and a water circulation flow rate adjustment unit 66 as multiple functions. The refrigerant circuit switching unit 64 controls the refrigerant circuit switching valve 32 so that the refrigerant circuit 7 switches to one of the following: a cooling sensible heat hot water supply cycle, a cooling total heat hot water supply cycle, a heating sensible heat hot water supply cycle, a heating total heat hot water supply cycle, a cooling-only cycle, a heating-only cycle, or a hot water-only cycle. The water circuit switching unit 65 controls the switching valve 14 so that the pump 12 is connected to either the first water-refrigerant heat exchanger 15 or the second water-refrigerant heat exchanger 16. The water circuit switching unit 65 further controls the hot water tank inlet switching valve 18 so that the water confluence unit 17 is connected to either the first inlet 22 or the second inlet 23. The water circulation flow rate adjustment unit 66 obtains the inlet water temperature measured by the inlet water temperature sensor 52 and the outlet water temperature measured by the outlet water temperature sensor 53 from the outlet water temperature sensor 53. The water circulation flow rate adjustment unit 66 further controls the pump 12 to adjust the pump rotation speed based on the inlet water temperature and the outlet water temperature.

[0036] [Operation of Refrigeration Cycle Device 1] The water pressure of the water stored inside the hot water tank 11 decreases when the faucet connected to the hot water connection port 29 is opened. Tap water supplied from the water supply connection port 26 to the pressure reducing valve 27 flows through the pressure reducing valve 27 so that when the water pressure inside the hot water tank 11 decreases, the water pressure inside the hot water tank 11 is maintained at a constant water pressure lower than the water pressure of the tap water at the water supply connection port 26. A portion of the tap water that has flowed through the pressure reducing valve 27 flows into the lower space of the hot water tank 11 via the water inlet 25. High-temperature water is stored in the upper space of the hot water tank 11, and low-temperature water, which is at a lower temperature than the high-temperature water, is stored in the lower space of the hot water tank 11. The low-temperature water stored in the lower space of the hot water tank 11 is mixed with tap water and increases as tap water flows into the lower space of the hot water tank 11 via the water inlet 25.

[0037] A portion of the high-temperature water stored in the upper space of the hot water tank 11 is pushed aside by the increasing amount of low-temperature water stored in the lower space of the hot water tank 11, and flows into the hot water mixing valve 28 via the hot water outlet 24. The amount of high-temperature water stored in the upper space of the hot water tank 11 decreases as a portion of the high-temperature water flows into the hot water mixing valve 28. The high-temperature water that flows into the hot water mixing valve 28 is mixed with a portion of the tap water that has flowed through the pressure reducing valve 27, resulting in hot water at a preset hot water temperature. The hot water flows out from the hot water mixing valve 28 and out from the faucet connected to the hot water connection port 29 via the faucet, as the faucet connected to the hot water connection port 29 is open.

[0038] When the refrigeration cycle unit 1 receives both a request for cooling operation and a request for hot water supply from the user, the control device 61 executes either cooling sensible heat hot water supply operation or cooling total heat hot water supply operation. [Cooling sensible heat hot water supply operation] In cooling sensible heat hot water supply operation, the control device 61 controls the refrigerant circuit switching valve 32 to switch the refrigerant circuit 7 to the cooling sensible heat hot water supply cycle and drives the compressor 31. The compressor 31 compresses the low-pressure gaseous refrigerant that has been drawn into the compressor 31. The low-pressure gaseous refrigerant is compressed by the compressor 31 and becomes high-pressure gaseous refrigerant. The high-pressure gaseous refrigerant flows into the first water refrigerant heat exchanger 15 because the refrigerant circuit 7 has been switched to the cooling sensible heat hot water supply cycle.

[0039] The first water-refrigerant heat exchanger 15 exchanges heat between the high-pressure gaseous refrigerant flowing into the first water-refrigerant heat exchanger 15 and the low-temperature water flowing into the first water-refrigerant heat exchanger 15 via the water circuit 6, thereby cooling the high-pressure gaseous refrigerant flowing into the first water-refrigerant heat exchanger 15. The high-pressure gaseous refrigerant flowing into the first water-refrigerant heat exchanger 15 does not condense in the first water-refrigerant heat exchanger 15, but becomes a post-heat-dissipating refrigerant with a lower temperature. The post-heat-dissipating refrigerant flows out of the first water-refrigerant heat exchanger 15, and because the refrigerant circuit 7 has switched to the cooling sensible heat hot water supply cycle, it does not flow into the second water-refrigerant heat exchanger 16, but instead flows into the outdoor heat exchanger 33 via the first three-way valve 48.

[0040] The outdoor fan 51 of the outdoor unit 2 passes outside air through the outdoor heat exchanger 33. The outdoor heat exchanger 33 exchanges heat between the post-heat-dissipating refrigerant that flows into the outdoor heat exchanger 33 and the outside air, causing the post-heat-dissipating refrigerant that flows into the outdoor heat exchanger 33 to further dissipate heat. The post-heat-dissipating refrigerant that flows into the outdoor heat exchanger 33 is cooled and condensed by the outdoor heat exchanger 33, becoming high-pressure liquid-phase refrigerant. In other words, the outdoor heat exchanger 33 functions as a condenser when cooling sensible heat hot water supply operation is performed. The high-pressure liquid-phase refrigerant flows out of the outdoor heat exchanger 33, flows into the outdoor expansion valve 34, and flows into the indoor expansion valve 37 via the receiver 35. The high-pressure liquid-phase refrigerant is depressurized by the outdoor expansion valve 34 and the indoor expansion valve 37, becoming low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant flows out of the indoor expansion valve 37 and flows into the indoor heat exchanger 38. Furthermore, since the boiling expansion valve 36 is closed, the refrigerant that has been depressurized by the outdoor expansion valve 34 does not flow into the boiling expansion valve 36.

[0041] The indoor unit 3 uses a fan (not shown) to pass the air from the room in which it is installed through the indoor heat exchanger 38. The indoor heat exchanger 38 exchanges heat between the air and the low-pressure gas-liquid two-phase refrigerant, cooling the air and heating the low-pressure gas-liquid two-phase refrigerant. The indoor unit 3 then blows the air cooled by the indoor heat exchanger 38 into the room. The room in which the indoor unit 3 is installed is cooled by the air cooled by the indoor heat exchanger 38 being blown into the room. In other words, the indoor unit 3 cools the room using the heat of the refrigerant. The low-pressure gas-liquid two-phase refrigerant is heated by the indoor heat exchanger 38, evaporates, and becomes a low-pressure gaseous phase refrigerant. That is, the indoor heat exchanger 38 functions as an evaporator when the cooling sensible heat hot water supply operation is performed. The low-pressure gaseous phase refrigerant is drawn into the compressor 31 when the refrigerant circuit 7 is switched to the cooling sensible heat hot water supply cycle.

[0042] In cooling sensible heat hot water supply operation, the control device 61 further controls the switching valve 14 to switch the flow path of the water circuit 6 so that the pump 12 is connected to the first water refrigerant heat exchanger 15. The control device 61 further controls the hot water tank inlet switching valve 18 to switch the flow path of the water circuit 6 so that the water confluence 17 is connected to the hot water tank 11 via the first inlet 22. The control device 61 further drives the pump 12. The low-temperature water stored in the lower space of the hot water tank 11 is reduced as the pump 12 is driven and flows out of the hot water tank 11 via the outlet 21. The low-temperature water that has flowed out of the hot water tank 11 flows into the first water refrigerant heat exchanger 15 via the pump 12 and the switching valve 14.

[0043] The first water-refrigerant heat exchanger 15 exchanges heat between the high-pressure gas-phase refrigerant flowing through the first water-refrigerant heat exchanger 15 and the low-temperature water that has flowed into the first water-refrigerant heat exchanger 15, thereby heating the low-temperature water. The low-temperature water is heated by the first water-refrigerant heat exchanger 15 to become high-temperature water. That is, in the cooling sensible heat hot water supply operation, the first water-refrigerant heat exchanger 15 heats water while the indoor unit 3 performs cooling. The high-temperature water flows into the first inlet 22 of the hot water supply tank 11 via the water merging section 17 and the hot water supply tank inlet switching valve 18, and flows into the upper space of the hot water supply tank 11 via the first inlet 22. The amount of high-temperature water stored in the hot water supply tank 11 increases because the high-temperature water heated by the first water-refrigerant heat exchanger 15 flows into the upper space of the hot water supply tank 11 and mixes with the existing high-temperature water heated by the first water-refrigerant heat exchanger 15.

[0044] The control device 61 executes water circulation flow rate control when the cooling sensible heat hot water supply operation is being performed. In the water circulation flow rate control, the control device 61 intermittently acquires the incoming water temperature measured by the incoming water temperature sensor 52 from the incoming water temperature sensor 52, and calculates a target outgoing hot water temperature based on the incoming water temperature. The target outgoing hot water temperature increases as the incoming water temperature rises. For example, the target outgoing hot water temperature is a value calculated by adding a constant 5 (K) to the incoming water temperature. The control device 61 further intermittently acquires the outgoing hot water temperature measured by the outgoing hot water temperature sensor 53 from the outgoing hot water temperature sensor 53. The control device 61 controls the pump 12 and adjusts the pump rotation speed of the pump 12 so that the outgoing hot water temperature approaches the target outgoing hot water temperature. That is, when the outgoing hot water temperature is lower than the target outgoing hot water temperature, the control device 61 reduces the pump rotation speed, and when the outgoing hot water temperature is higher than the target outgoing hot water temperature, the control device 61 increases the pump rotation speed.

[0045] Figure 3 is a Mollier diagram showing the state change of the refrigerant in the refrigerant circuit 7 when cooling sensible heat hot water supply operation is being performed. In the first water refrigerant heat exchanger 15, when cooling sensible heat hot water supply operation is being performed, the high-pressure gas phase refrigerant is cooled without changing its state, that is, while maintaining a superheated gas state. In the outdoor heat exchanger 33, when cooling sensible heat hot water supply operation is being performed, the refrigerant is cooled so that it condenses after heat dissipation. The heat transfer coefficient and heat transfer area of ​​the first water refrigerant heat exchanger 15 are determined so that the refrigerant maintains a superheated gas state after heat dissipation when cooling sensible heat hot water supply operation is being performed. When cooling sensible heat hot water supply operation is being performed, the refrigeration cycle device 1 can appropriately heat the low-temperature water to a temperature higher than the condensation temperature when the refrigerant changes state in the outdoor heat exchanger 33 by using the sensible heat of the high-pressure gas phase refrigerant to heat the low-temperature water.

[0046] When cooling sensible heat hot water supply operation is being performed, the control device 61 further determines the relationship between the target hot water outlet temperature used in water circulation flow rate control and a predetermined target hot water outlet temperature threshold. 60°C is an example of the target hot water outlet temperature threshold. The control device 61 maintains the cooling sensible heat hot water supply operation when the target hot water outlet temperature is equal to or greater than the target hot water outlet temperature threshold. The control device 61 performs cooling total heat hot water supply operation when the target hot water outlet temperature is less than the target hot water outlet temperature threshold. In other words, the control device 61 controls the refrigerant circuit switching valve 32 and switches the operation to be performed based on the inlet water temperature, specifically based on the target hot water outlet temperature determined by the inlet water temperature.

[0047] [Cooling and Total Heat Supply Operation] In cooling and total heat supply operation, the control device 61 controls the refrigerant circuit switching valve 32 to switch the refrigerant circuit 7 to the cooling and total heat supply cycle. The compressor 31 compresses the low-pressure gaseous refrigerant that is drawn into the compressor 31. The low-pressure gaseous refrigerant is compressed by the compressor 31 and becomes high-pressure gaseous refrigerant. Because the refrigerant circuit 7 has been switched to the cooling and total heat supply cycle, the high-pressure gaseous refrigerant flows into the second water refrigerant heat exchanger 16 via the refrigerant circuit switching valve 32.

[0048] The second water-refrigerant heat exchanger 16 exchanges heat between the high-pressure gas-phase refrigerant flowing into the second water-refrigerant heat exchanger 16 and the low-temperature water flowing into the second water-refrigerant heat exchanger 16 in the water circuit 6, and cools the high-pressure gas-phase refrigerant flowing into the second water-refrigerant heat exchanger 16. The high-pressure gas-phase refrigerant flowing into the second water-refrigerant heat exchanger 16 is cooled by the second water-refrigerant heat exchanger 16, condensed, and becomes a high-pressure liquid-phase refrigerant. That is, the second water-refrigerant heat exchanger 16 functions as a condenser when a cooling total heat hot water supply operation is performed. The high-pressure liquid-phase refrigerant flows out from the second water-refrigerant heat exchanger 16, flows into the boiling expansion valve 36, and flows into the indoor expansion valve 37 via the receiver 35. The high-pressure liquid-phase refrigerant is depressurized by the boiling expansion valve 36 and the indoor expansion valve 37, and becomes a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant flows out from the indoor expansion valve 37 and flows into the indoor heat exchanger 38. Note that since the outdoor expansion valve 34 is closed, the refrigerant depressurized by the boiling expansion valve 36 does not flow into the outdoor expansion valve 34.

[0049] The indoor unit 3 allows air in a room where the indoor unit 3 is installed to pass through the indoor heat exchanger 38 by a fan (not shown). The indoor heat exchanger 38 exchanges heat between the low-pressure gas-liquid two-phase refrigerant and air, cools the air, and heats the low-pressure gas-liquid two-phase refrigerant. The indoor unit 3 further blows out the air cooled by the indoor heat exchanger 38 into the room. The room where the indoor unit 3 is installed is cooled by the air cooled by the indoor heat exchanger 38 being blown into the room. The low-pressure gas-liquid two-phase refrigerant is heated by the indoor heat exchanger 38, evaporated, and becomes a low-pressure gas-phase refrigerant. That is, the indoor heat exchanger 38 functions as an evaporator when a cooling total heat hot water supply operation is performed. The low-pressure gas-phase refrigerant is sucked into the compressor 31 because the refrigerant circuit 7 is switched to the cooling total heat hot water supply cycle.

[0050] In total heating and cooling operation, the control device 61 further controls the switching valve 14 to switch the flow path of the water circuit 6 so that the pump 12 is connected to the second water refrigerant heat exchanger 16. The control device 61 further controls the hot water tank inlet switching valve 18 to switch the flow path of the water circuit 6 so that the water confluence 17 is connected to the hot water tank 11 via the second inlet 23. The control device 61 further drives the pump 12. The low-temperature water stored in the lower space of the hot water tank 11 is reduced as the pump 12 is driven and flows out of the hot water tank 11 via the outlet 21. The low-temperature water that has flowed out of the hot water tank 11 flows into the second water refrigerant heat exchanger 16 via the switching valve 14.

[0051] The second water refrigerant heat exchanger 16 exchanges heat between the high-pressure gaseous refrigerant flowing through the second water refrigerant heat exchanger 16 and the low-temperature water flowing into the second water refrigerant heat exchanger 16, thereby heating the low-temperature water. The low-temperature water is heated by the second water refrigerant heat exchanger 16 and becomes high-temperature water. In other words, in cooling and total heat supply operation, the indoor unit 3 cools while the second water refrigerant heat exchanger 16 heats the water. The high-temperature water flows into the second inlet 23 of the hot water supply tank 11 via the water confluence section 17 and the hot water supply tank inlet switching valve 18, and then flows into the hot water supply tank 11 via the second inlet 23. The low-temperature water stored in the lower space of the hot water supply tank 11 is mixed with the high-temperature water heated by the second water refrigerant heat exchanger 16 as the high-temperature water heated by the second water refrigerant heat exchanger 16 flows into the hot water supply tank 11 via the second inlet 23, increasing in volume and raising its temperature.

[0052] Figure 4 is a Mollier diagram showing the state change of the refrigerant in the refrigerant circuit 7 when cooling total heat supply operation is being performed. The second water refrigerant heat exchanger 16 cools the high-pressure gas phase refrigerant so that it condenses when cooling total heat supply operation is being performed. For this reason, the temperature of the high-temperature water heated by the second water refrigerant heat exchanger 16 may not be higher than the condensation temperature when the high-pressure gas phase refrigerant is undergoing a state change in the second water refrigerant heat exchanger 16. In other words, the refrigeration cycle device 1 can make the temperature of the high-temperature water heated by the second water refrigerant heat exchanger 16 higher when cooling sensible heat supply operation is being performed than the temperature of the high-temperature water heated by the second water refrigerant heat exchanger 16 when cooling total heat supply operation is being performed.

[0053] Furthermore, when the total heat supply operation for cooling is being performed, the temperature of the high-temperature water heated by the second water refrigerant heat exchanger 16 may be lower than the temperature of the high-temperature water stored in the upper space of the hot water supply tank 11. Even in such cases, the refrigeration cycle device 1 can suppress a decrease in the temperature of the high-temperature water stored in the upper space of the hot water supply tank 11 by allowing the high-temperature water heated by the second water refrigerant heat exchanger 16 to flow into the hot water supply tank 11 via the second inlet 23.

[0054] When cooling total heat hot water supply operation is being performed, the control device 61 performs water circulation flow rate control in the same way as when cooling sensible heat hot water supply operation is being performed. When cooling total heat hot water supply operation is being performed, the control device 61 further determines the relationship between the target hot water outlet temperature and the target hot water outlet temperature threshold used in water circulation flow rate control. When the target hot water outlet temperature is less than the target hot water outlet temperature threshold, the control device 61 maintains the execution of cooling total heat hot water supply operation. When the target hot water outlet temperature is equal to or greater than the target hot water outlet temperature threshold, the control device 61 executes cooling sensible heat hot water supply operation.

[0055] The refrigeration cycle device 1 can heat water to a high temperature without increasing the pressure of the refrigerant discharged from the compressor 31 by switching from total heat cooling hot water supply operation to sensible heat cooling hot water supply operation when the target hot water temperature is high (when the target hot water temperature is equal to or greater than the target hot water temperature threshold). Therefore, low-temperature water can be appropriately heated to the target hot water temperature while ensuring reliability without increasing the compression ratio when the compressor 31 compresses the refrigerant. The hot water supply capacity or COP (Coefficient Of Performance) may decrease when sensible heat cooling hot water supply operation is performed compared to when total heat cooling hot water supply operation is performed. However, the refrigeration cycle device 1 can improve energy efficiency by switching from sensible heat cooling hot water supply operation to total heat cooling hot water supply operation when the target hot water temperature is below the target hot water temperature threshold, i.e., when the compression ratio does not increase.

[0056] When the refrigeration cycle device 1 receives both a request for heating operation and a request for hot water supply from the user, the control device 61 executes either a heating sensible heat hot water supply operation or a heating total heat hot water supply operation. [Heating Sensible Heat Hot Water Supply Operation] In heating sensible heat hot water supply operation, the control device 61 controls the refrigerant circuit switching valve 32 to switch the refrigerant circuit 7 to the heating sensible heat hot water supply cycle and drives the compressor 31. The compressor 31 compresses the low-pressure gaseous refrigerant that has been drawn into the compressor 31. The low-pressure gaseous refrigerant is compressed by the compressor 31 and becomes a high-pressure gaseous refrigerant. The high-pressure gaseous refrigerant flows into the first water refrigerant heat exchanger 15 because the refrigerant circuit 7 has been switched to the heating sensible heat hot water supply cycle.

[0057] The first water-refrigerant heat exchanger 15 exchanges heat between the high-pressure gaseous refrigerant flowing into the first water-refrigerant heat exchanger 15 and the low-temperature water flowing into the first water-refrigerant heat exchanger 15 via the water circuit 6, thereby cooling the high-pressure gaseous refrigerant flowing into the first water-refrigerant heat exchanger 15. The high-pressure gaseous refrigerant flowing into the first water-refrigerant heat exchanger 15 does not condense in the first water-refrigerant heat exchanger 15, but becomes a post-heat-dissipating refrigerant with a lower temperature. The post-heat-dissipating refrigerant flows out of the first water-refrigerant heat exchanger 15, and because the refrigerant circuit 7 has switched to the heating sensible heat hot water supply cycle, it does not flow into the second water-refrigerant heat exchanger 16, but instead flows into the indoor heat exchanger 38 via the second three-way valve 49.

[0058] The indoor unit 3 uses a fan (not shown) to pass the air from the room in which it is installed through the indoor heat exchanger 38. The indoor heat exchanger 38 exchanges heat between the refrigerant (after heat dissipation) and the air, heating the air and causing the refrigerant (after heat dissipation) to further dissipate heat. The indoor unit 3 then blows the air heated by the indoor heat exchanger 38 into the room. The room in which the indoor unit 3 is installed is heated by the air heated by the indoor heat exchanger 38 being blown into the room. In other words, the indoor unit 3 heats the room using the heat of the refrigerant. After heat dissipation, the refrigerant is cooled and condensed by the indoor heat exchanger 38, becoming a high-pressure liquid-phase refrigerant. That is, the indoor heat exchanger 38 functions as a condenser when heating sensible heat hot water supply operation is performed.

[0059] The high-pressure liquid-phase refrigerant flows out of the indoor heat exchanger 38, into the indoor expansion valve 37, and then into the outdoor expansion valve 34 via the receiver 35. The high-pressure liquid-phase refrigerant is depressurized by the indoor expansion valve 37 and the outdoor expansion valve 34, becoming a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant flows out of the outdoor expansion valve 34 and into the outdoor heat exchanger 33. Since the boiling expansion valve 36 is closed, the refrigerant depressurized by the indoor expansion valve 37 does not flow into the boiling expansion valve 36.

[0060] The outdoor fan 51 of the outdoor unit 2 passes outside air through the outdoor heat exchanger 33. The outdoor heat exchanger 33 exchanges heat between the low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33 and the outside air, heating the low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33. The low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33 is heated by the outdoor heat exchanger 33, evaporates, and becomes low-pressure gas phase refrigerant. In other words, the outdoor heat exchanger 33 functions as an evaporator when heating sensible heat hot water supply operation is performed. The low-pressure gas phase refrigerant is drawn into the compressor 31 because the refrigerant circuit 7 has switched to the heating sensible heat hot water supply cycle.

[0061] In heating sensible heat hot water supply operation, the control device 61 further controls the switching valve 14 to switch the flow path of the water circuit 6 so that the pump 12 is connected to the first water-refrigerant heat exchanger 15. The control device 61 further controls the hot water tank inlet switching valve 18 to switch the flow path of the water circuit 6 so that the water confluence 17 is connected to the hot water tank 11 via the first inlet 22. The control device 61 further drives the pump 12. The low-temperature water stored in the lower space of the hot water tank 11 is reduced as the pump 12 is driven and flows out of the hot water tank 11 via the outlet 21. The low-temperature water that has flowed out of the hot water tank 11 flows into the first water-refrigerant heat exchanger 15 via the switching valve 14.

[0062] The first water-refrigerant heat exchanger 15 exchanges heat between the high-pressure gaseous refrigerant flowing through the first water-refrigerant heat exchanger 15 and the low-temperature water flowing into the first water-refrigerant heat exchanger 15, thereby heating the low-temperature water. The low-temperature water is heated by the first water-refrigerant heat exchanger 15 and becomes high-temperature water. In other words, in heating sensible heat hot water supply operation, the indoor unit 3 cools while the first water-refrigerant heat exchanger 15 heats the water. The high-temperature water flows into the first inlet 22 of the hot water supply tank 11 via the water confluence section 17 and the hot water supply tank inlet switching valve 18, and flows into the upper space of the hot water supply tank 11 via the first inlet 22. The high-temperature water stored in the hot water supply tank 11 is increased as the high-temperature water heated by the first water-refrigerant heat exchanger 15 flows into the upper space of the hot water supply tank 11 and mixes with the high-temperature water heated by the first water-refrigerant heat exchanger 15.

[0063] Figure 5 is a Mollier diagram showing the state change of the refrigerant in the refrigerant circuit 7 when heating and sensible heat hot water supply operation is being performed. In the first water-refrigerant heat exchanger 15, when heating and sensible heat hot water supply operation is being performed, the high-pressure gas-phase refrigerant is cooled without changing its state, that is, while maintaining a superheated gas state. In the indoor heat exchanger 38, when heating and sensible heat hot water supply operation is being performed, the refrigerant is cooled so that it condenses after heat dissipation. The heat transfer coefficient and heat transfer area of ​​the first water-refrigerant heat exchanger 15 are determined so that the refrigerant maintains a superheated gas state after heat dissipation when heating and sensible heat hot water supply operation is being performed. When heating and sensible heat hot water supply operation is being performed, the refrigeration cycle device 1 can appropriately heat the low-temperature water to a temperature higher than the condensation temperature when the refrigerant changes state in the indoor heat exchanger 38 by using the sensible heat of the high-pressure gas-phase refrigerant to heat the low-temperature water.

[0064] When heating sensible heat hot water supply operation is being performed, the control device 61 performs water circulation flow rate control in the same way as when cooling sensible heat hot water supply operation is being performed. When heating sensible heat hot water supply operation is being performed, the control device 61 further determines the relationship between the target hot water outlet temperature and the target hot water outlet temperature threshold used in water circulation flow rate control. When the target hot water outlet temperature is equal to or greater than the target hot water outlet temperature threshold, the control device 61 maintains the execution of heating sensible heat hot water supply operation. When the target hot water outlet temperature is less than the target hot water outlet temperature threshold, the control device 61 executes heating total heat hot water supply operation.

[0065] [Heating Total Heat Supply Operation] In heating total heat supply operation, the control device 61 controls the refrigerant circuit switching valve 32 to switch the refrigerant circuit 7 to the heating total heat supply cycle. The compressor 31 compresses the low-pressure gaseous refrigerant drawn into the compressor 31. The low-pressure gaseous refrigerant is compressed by the compressor 31 and becomes high-pressure gaseous refrigerant. Because the refrigerant circuit 7 has been switched to the heating total heat supply cycle, a portion of the high-pressure gaseous refrigerant (first refrigerant) flows into the second water refrigerant heat exchanger 16 via the refrigerant circuit switching valve 32, and the remainder of the high-pressure gaseous refrigerant (second refrigerant) flows into the indoor heat exchanger 38 via the refrigerant circuit switching valve 32. The second water refrigerant heat exchanger 16 exchanges heat between the high-pressure gaseous refrigerant that has flowed into the second water refrigerant heat exchanger 16 and the low-temperature water that has flowed into the second water refrigerant heat exchanger 16, thereby cooling the high-pressure gaseous refrigerant that has flowed into the second water refrigerant heat exchanger 16. The high-pressure gaseous refrigerant flowing into the second water refrigerant heat exchanger 16 is cooled and condensed in the second water refrigerant heat exchanger 16, becoming a high-pressure liquid-phase refrigerant. In other words, the second water refrigerant heat exchanger 16 functions as a condenser when heating and total heat supply hot water operation is performed. The high-pressure liquid-phase refrigerant flows out of the second water refrigerant heat exchanger 16, flows into the boiling expansion valve 36, and flows into the outdoor expansion valve 34 via the receiver 35.

[0066] The indoor unit 3 uses a fan (not shown) to pass the air from the room in which it is installed through the indoor heat exchanger 38. The indoor heat exchanger 38 exchanges heat between the low-pressure gas-liquid two-phase refrigerant and the air, heating the air and cooling the high-pressure gas-phase refrigerant. The indoor unit 3 then blows the air heated by the indoor heat exchanger 38 into the room. The room in which the indoor unit 3 is installed is heated by the air heated by the indoor heat exchanger 38 being blown into the room. The high-pressure gas-phase refrigerant is cooled and condensed by the indoor heat exchanger 38 to become a high-pressure liquid-phase refrigerant. In other words, the indoor heat exchanger 38 functions as a condenser when heating and total heat supply operation is performed. The high-pressure liquid-phase refrigerant flows out of the indoor heat exchanger 38, flows into the indoor expansion valve 37, and flows into the outdoor expansion valve 34 via the receiver 35. In other words, the refrigerant that flows from the second water-refrigerant heat exchanger 16 into the boiling expansion valve 36 and is depressurized, and the refrigerant that flows from the indoor heat exchanger 38 into the indoor expansion valve 37 and is depressurized, flow into the receiver 35 and merge, where they are further depressurized in the outdoor expansion valve 34 to become a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant flows out from the outdoor expansion valve 34 and into the outdoor heat exchanger 33.

[0067] The outdoor fan 51 of the outdoor unit 2 passes outside air through the outdoor heat exchanger 33. The outdoor heat exchanger 33 exchanges heat between the low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33 and the outside air, heating the low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33. The low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33 is heated by the outdoor heat exchanger 33, evaporates, and becomes low-pressure gaseous refrigerant. In other words, the outdoor heat exchanger 33 functions as an evaporator when the heating total heat supply operation is performed. The low-pressure gaseous refrigerant is drawn into the compressor 31 because the refrigerant circuit 7 has switched to the heating total heat supply cycle.

[0068] In total heating and hot water supply operation, the control device 61 further controls the switching valve 14 to switch the flow path of the water circuit 6 so that the pump 12 is connected to the second water-refrigerant heat exchanger 16. The control device 61 further controls the hot water tank inlet switching valve 18 to switch the flow path of the water circuit 6 so that the water confluence section 17 is connected to the second inlet 23 of the hot water tank 11 via the hot water tank inlet switching valve 18. The control device 61 further drives the pump 12. The low-temperature water stored in the lower space of the hot water tank 11 is reduced as the pump 12 is driven and flows out of the hot water tank 11 via the outlet 21. The low-temperature water that has flowed out of the hot water tank 11 flows into the second water-refrigerant heat exchanger 16 via the switching valve 14.

[0069] The second water refrigerant heat exchanger 16 exchanges heat between the high-pressure gaseous refrigerant flowing through the second water refrigerant heat exchanger 16 and the low-temperature water flowing into the second water refrigerant heat exchanger 16, thereby heating the low-temperature water. The low-temperature water is heated by the second water refrigerant heat exchanger 16 and becomes high-temperature water. In other words, in total heating and hot water supply operation, the indoor unit 3 cools while the second water refrigerant heat exchanger 16 heats the water. The high-temperature water flows into the second inlet 23 of the hot water supply tank 11 via the water confluence section 17 and the hot water supply tank inlet switching valve 18, and then flows into the hot water supply tank 11 via the second inlet 23. The low-temperature water stored in the lower space of the hot water supply tank 11 is mixed with the high-temperature water heated by the second water refrigerant heat exchanger 16 as the high-temperature water heated by the second water refrigerant heat exchanger 16 flows into the hot water supply tank 11 via the second inlet 23, increasing in volume and raising its temperature.

[0070] Figure 6 is a Mollier diagram showing the state change of the refrigerant in the refrigerant circuit 7 when heating and total heat supply operation is being performed. The second water refrigerant heat exchanger 16 cools the high-pressure gas phase refrigerant so that it condenses when heating and total heat supply operation is being performed. For this reason, the temperature of the high-temperature water heated by the second water refrigerant heat exchanger 16 may not be higher than the condensation temperature when the high-pressure gas phase refrigerant is undergoing a state change in the second water refrigerant heat exchanger 16. In other words, the refrigeration cycle device 1 can make the temperature of the high-temperature water heated by the second water refrigerant heat exchanger 16 higher when heating and sensible heat supply operation is being performed than the temperature of the high-temperature water heated by the second water refrigerant heat exchanger 16 when heating and total heat supply operation is being performed.

[0071] Furthermore, when total heating and hot water supply operation is being performed, the temperature of the high-temperature water heated by the second water-refrigerant heat exchanger 16 may be lower than the temperature of the high-temperature water stored in the upper space of the hot water supply tank 11. Even in such cases, the refrigeration cycle device 1 can suppress a decrease in the temperature of the high-temperature water stored in the upper space of the hot water supply tank 11 by allowing the high-temperature water heated by the second water-refrigerant heat exchanger 16 to flow into the hot water supply tank 11 via the second inlet 23.

[0072] When total heating hot water supply operation is being performed, the control device 61 performs water circulation flow rate control in the same way as when sensible heating hot water supply operation is being performed. When total heating hot water supply operation is being performed, the control device 61 further determines the relationship between the target hot water outlet temperature and the target hot water outlet temperature threshold used in water circulation flow rate control. When the target hot water outlet temperature is less than the target hot water outlet temperature threshold, the control device 61 maintains the execution of total heating hot water supply operation. When the target hot water outlet temperature is equal to or greater than the target hot water outlet temperature threshold, the control device 61 executes sensible heating hot water supply operation.

[0073] The refrigeration cycle device 1 can heat water to a high temperature without increasing the pressure of the refrigerant discharged from the compressor 31 by switching from total heat heating operation to sensible heat heating operation when the target hot water temperature is high (when the target hot water temperature is equal to or greater than the target hot water temperature threshold). Therefore, it is possible to appropriately heat low-temperature water to the target hot water temperature while ensuring reliability without increasing the compression ratio when the compressor 31 compresses the refrigerant. The hot water supply capacity or COP may decrease when sensible heat heating operation is performed compared to when total heat heating operation is performed. However, the refrigeration cycle device 1 can improve energy efficiency by switching from sensible heat heating operation to total heat heating operation when the target hot water temperature is below the target hot water temperature threshold, i.e., when the compression ratio does not increase.

[0074] [Cooling-only operation] The control device 61 executes cooling-only operation when the refrigeration cycle device 1 receives a request for cooling operation from the user without receiving a request for hot water supply. In cooling-only operation, the control device 61 controls the refrigerant circuit switching valve 32 to switch the refrigerant circuit 7 to a cooling-only cycle and drives the compressor 31. The compressor 31 compresses the low-pressure gaseous refrigerant that is drawn into the compressor 31. The low-pressure gaseous refrigerant is compressed by the compressor 31 and becomes high-pressure gaseous refrigerant. Because the refrigerant circuit 7 has been switched to a cooling-only cycle, the high-pressure gaseous refrigerant flows into the outdoor heat exchanger 33 via the refrigerant circuit switching valve 32.

[0075] The outdoor fan 51 of the outdoor unit 2 passes outside air through the outdoor heat exchanger 33. The outdoor heat exchanger 33 exchanges heat between the high-pressure gaseous refrigerant flowing into the outdoor heat exchanger 33 and the outside air, cooling the high-pressure gaseous refrigerant flowing into the outdoor heat exchanger 33. The high-pressure gaseous refrigerant flowing into the outdoor heat exchanger 33 is cooled and condensed by the outdoor heat exchanger 33, becoming a high-pressure liquid-phase refrigerant. In other words, the outdoor heat exchanger 33 functions as a condenser when cooling-only operation is performed. The high-pressure liquid-phase refrigerant flows out of the outdoor heat exchanger 33, flows into the outdoor expansion valve 34, and flows into the indoor expansion valve 37 via the receiver 35. The high-pressure liquid-phase refrigerant is depressurized by the outdoor expansion valve 34 and the indoor expansion valve 37, becoming a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant flows out of the indoor expansion valve 37 and flows into the indoor heat exchanger 38. Furthermore, since the boiling expansion valve 36 is closed, the refrigerant that has been depressurized by the outdoor expansion valve 34 does not flow into the boiling expansion valve 36.

[0076] The indoor unit 3 uses a fan (not shown) to pass the air from the room in which it is installed through the indoor heat exchanger 38. The indoor heat exchanger 38 exchanges heat between the air and the low-pressure gas-liquid two-phase refrigerant, cooling the air and heating the low-pressure gas-liquid two-phase refrigerant. The indoor unit 3 then blows the air cooled by the indoor heat exchanger 38 into the room. The room in which the indoor unit 3 is installed is cooled by the air cooled by the indoor heat exchanger 38 being blown into the room. The low-pressure gas-liquid two-phase refrigerant is heated by the indoor heat exchanger 38, evaporates, and becomes low-pressure gaseous refrigerant. In other words, the indoor heat exchanger 38 functions as an evaporator when cooling-only operation is performed. The low-pressure gaseous refrigerant is drawn into the compressor 31 when the refrigerant circuit 7 is switched to the cooling-only cycle.

[0077] In cooling-only operation, the control device 61 stops the pump 12 so that water does not circulate in the water circuit 6. In other words, the refrigeration cycle device 1 can properly cool the room without heating the low-temperature water stored in the lower space of the hot water tank 11.

[0078] [Heating-only operation] The control device 61 executes heating-only operation when the refrigeration cycle device 1 receives a request for heating operation from the user without receiving a request for hot water supply. In heating-only operation, the control device 61 controls the refrigerant circuit switching valve 32 to switch the refrigerant circuit 7 to a heating-only cycle and drives the compressor 31. The compressor 31 compresses the low-pressure gaseous refrigerant that is drawn into the compressor 31. The low-pressure gaseous refrigerant is compressed by the compressor 31 and becomes high-pressure gaseous refrigerant. Because the refrigerant circuit 7 has been switched to a heating-only cycle, the high-pressure gaseous refrigerant flows into the indoor heat exchanger 38 via the refrigerant circuit switching valve 32.

[0079] The indoor unit 3 uses a fan (not shown) to pass the air from the room in which it is installed through the indoor heat exchanger 38. The indoor heat exchanger 38 exchanges heat between the high-pressure gaseous refrigerant and the air, heating the air and cooling the high-pressure gaseous refrigerant. The indoor unit 3 then blows the air heated by the indoor heat exchanger 38 into the room. The room in which the indoor unit 3 is installed is heated by the air heated by the indoor heat exchanger 38 being blown into the room. The high-pressure gaseous refrigerant is cooled and condensed by the indoor heat exchanger 38 to become a high-pressure liquid refrigerant. In other words, the indoor heat exchanger 38 functions as a condenser when heating-only operation is performed. The high-pressure liquid refrigerant flows out of the indoor heat exchanger 38, flows into the indoor expansion valve 37, and flows into the outdoor expansion valve 34 via the receiver 35. The high-pressure liquid refrigerant is depressurized by the outdoor expansion valve 34 and the indoor expansion valve 37 to become a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant flows out from the outdoor expansion valve 34 and into the outdoor heat exchanger 33. Since the boiling expansion valve 36 is closed, the refrigerant that has been depressurized by the indoor expansion valve 37 does not flow into the boiling expansion valve 36.

[0080] The outdoor fan 51 of the outdoor unit 2 passes outside air through the outdoor heat exchanger 33. The outdoor heat exchanger 33 exchanges heat between the low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33 and the outside air, heating the low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33. The low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33 is heated by the outdoor heat exchanger 33, evaporates, and becomes low-pressure gaseous refrigerant. In other words, the outdoor heat exchanger 33 functions as an evaporator when heating-only operation is performed. The low-pressure gaseous refrigerant is drawn into the compressor 31 when the refrigerant circuit 7 is switched to a heating-only cycle.

[0081] In heating-only operation, the control device 61 stops the pump 12 so that water does not circulate in the water circuit 6. In other words, the refrigeration cycle device 1 can properly heat the room without heating the low-temperature water stored in the lower space of the hot water tank 11.

[0082] [Hot water only operation] The control device 61 performs hot water only operation when the refrigeration cycle device 1 receives a request for hot water only and has not received a request for cooling or heating operation from the user. In hot water only operation, the control device 61 controls the refrigerant circuit switching valve 32 to switch the refrigerant circuit 7 to the hot water only cycle and drives the compressor 31. The compressor 31 compresses the low-pressure gaseous refrigerant that has been drawn into the compressor 31. The low-pressure gaseous refrigerant is compressed by the compressor 31 and becomes high-pressure gaseous refrigerant. Because the refrigerant circuit 7 has been switched to the hot water only cycle, the high-pressure gaseous refrigerant flows into the second water refrigerant heat exchanger 16 via the refrigerant circuit switching valve 32.

[0083] The second water refrigerant heat exchanger 16 exchanges heat between the high-pressure gaseous refrigerant flowing into the second water refrigerant heat exchanger 16 and the low-temperature water flowing into the second water refrigerant heat exchanger 16, cooling the high-pressure gaseous refrigerant flowing into the second water refrigerant heat exchanger 16. The high-pressure gaseous refrigerant flowing into the second water refrigerant heat exchanger 16 is cooled and condensed in the second water refrigerant heat exchanger 16, becoming a high-pressure liquid-phase refrigerant. In other words, the second water refrigerant heat exchanger 16 functions as a condenser when hot water supply-only operation is performed. The high-pressure liquid-phase refrigerant flows out of the second water refrigerant heat exchanger 16, flows into the boiling expansion valve 36, and flows into the outdoor expansion valve 34 via the receiver 35. The high-pressure liquid-phase refrigerant is depressurized by the boiling expansion valve 36 and the outdoor expansion valve 34, becoming a low-pressure gas-liquid two-phase refrigerant. The low-pressure gas-liquid two-phase refrigerant flows out of the outdoor expansion valve 34 and flows into the outdoor heat exchanger 33. Furthermore, since the indoor expansion valve 37 is closed, the refrigerant that has been depressurized by the boiling expansion valve 36 does not flow into the indoor expansion valve 37.

[0084] The outdoor fan 51 of the outdoor unit 2 passes outside air through the outdoor heat exchanger 33. The outdoor heat exchanger 33 exchanges heat between the low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33 and the outside air, heating the low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33. The low-pressure gas-liquid two-phase refrigerant that flows into the outdoor heat exchanger 33 is heated by the outdoor heat exchanger 33, evaporates, and becomes low-pressure gaseous refrigerant. In other words, the outdoor heat exchanger 33 functions as an evaporator when hot water supply-only operation is performed. The low-pressure gaseous refrigerant is drawn into the compressor 31 because the refrigerant circuit 7 has switched to the hot water supply-only cycle.

[0085] In hot water supply-only operation, the control device 61 further controls the switching valve 14 to switch the flow path of the water circuit 6 so that the pump 12 is connected to the second water-refrigerant heat exchanger 16. The control device 61 further controls the hot water tank inlet switching valve 18 to switch the flow path of the water circuit 6 so that the water confluence section 17 is connected to the hot water tank 11 via the first inlet 22. The control device 61 further drives the pump 12. The low-temperature water stored in the lower space of the hot water tank 11 is reduced as the pump 12 is driven and flows out of the hot water tank 11 via the outlet 21. The low-temperature water that has flowed out of the hot water tank 11 flows into the second water-refrigerant heat exchanger 16 via the switching valve 14.

[0086] The second water refrigerant heat exchanger 16 exchanges heat between the high-pressure gaseous refrigerant flowing through the second water refrigerant heat exchanger 16 and the low-temperature water flowing into the second water refrigerant heat exchanger 16, thereby heating the low-temperature water. The low-temperature water is heated in the second water refrigerant heat exchanger 16 and becomes high-temperature water. The high-temperature water flows into the first inlet 22 of the hot water tank 11 via the water confluence section 17 and the hot water tank inlet switching valve 18, and flows into the upper space of the hot water tank 11 via the first inlet 22. The high-temperature water stored in the hot water tank 11 is increased as the high-temperature water heated by the second water refrigerant heat exchanger 16 flows into the upper space of the hot water tank 11 and mixes with the high-temperature water heated by the second water refrigerant heat exchanger 16. In other words, the refrigeration cycle device 1 can appropriately heat the low-temperature water stored in the lower space of the hot water tank 11 without the indoor unit 3 air conditioning the room, and can increase the amount of high-temperature water stored in the upper space of the hot water tank 11.

[0087] [Summary of the Refrigeration Cycle Device 1 of Example 1] The Refrigeration Cycle Device 1 of Example 1 comprises a refrigerant circuit 7, an indoor unit 3, a water circuit 6, and a first water-refrigerant heat exchanger 15, and is equipped with an outdoor heat exchanger 33 or an indoor heat exchanger 38. Refrigerant circulates through the refrigerant circuit 7. The indoor unit 3 uses the heat from the refrigerant to cool or heat the room. Water circulates through the water circuit 6. The first water-refrigerant heat exchanger 15 exchanges heat between the refrigerant and water so that the water is heated as the refrigerant releases heat. The outdoor heat exchanger 33 or indoor heat exchanger 38 further releases heat from the refrigerant that has already released heat in the first water-refrigerant heat exchanger 15 when the indoor unit 3 is cooling or heating the room and the first water-refrigerant heat exchanger 15 is heating the water.

[0088] In this case, the refrigeration cycle device 1 of Example 1 heats water using the sensible heat of the high-pressure gaseous refrigerant in the first water refrigerant heat exchanger 15. Therefore, the refrigeration cycle device 1 of Example 1 can heat water to a temperature higher than the condensation temperature of the high-pressure refrigerant, and can heat water to a high temperature without increasing the discharge pressure of the refrigerant. As a result, even when air conditioning and hot water supply are performed simultaneously, the refrigeration cycle device 1 of Example 1 does not need to increase the compression ratio when the compressor 31 of the refrigerant circuit 7 compresses the refrigerant, and the reliability of the compressor 31 can be ensured. Furthermore, the refrigeration cycle device 1 of Example 1 can heat water to a high temperature without using a heater even when the condensation temperature is low, and can heat water to a high temperature while reducing power consumption.

[0089] Furthermore, the refrigeration cycle device 1 of Embodiment 1 is further equipped with a refrigerant circuit switching valve 32 that switches the refrigerant flow path through which the refrigerant circulates in the refrigerant circuit 7. The refrigerant circuit switching valve 32 switches the refrigerant flow path through which the refrigerant circulates in the refrigerant circuit 7 so that the refrigerant circulates in the refrigerant circuit 7 so that after heat dissipation the refrigerant radiates heat in the outdoor heat exchanger 33 when the indoor unit 3 is performing a cooling sensible heat hot water supply operation in which the water is heated by the first water refrigerant heat exchanger 15. The refrigerant circuit switching valve 32 switches the refrigerant flow path so that the refrigerant radiates heat in the indoor heat exchanger 38 so that after heat dissipation the refrigerant radiates heat in the indoor heat exchanger 38 when the indoor unit 3 is performing a heating sensible heat hot water supply operation in which the water is heated by the first water refrigerant heat exchanger 15. At this time, the refrigeration cycle device 1 of Embodiment 1 can cool or heat the room while appropriately heating the water.

[0090] Furthermore, the refrigeration cycle device 1 of Embodiment 1 is further equipped with a second water refrigerant heat exchanger 16. The refrigerant circuit switching valve 32 switches the refrigerant flow path so that the refrigerant does not flow through the second water refrigerant heat exchanger 16 when cooling sensible heat hot water supply operation is performed. The refrigerant circuit switching valve 32 switches the refrigerant flow path so that the refrigerant flows through the second water refrigerant heat exchanger 16 when cooling total heat hot water supply operation is performed in which the indoor unit 3 cools the room and the water is heated by the second water refrigerant heat exchanger 16. The second water refrigerant heat exchanger 16 exchanges heat between the refrigerant and water so that the water is heated by the heat released by the refrigerant when cooling total heat hot water supply operation is performed. At this time, the refrigeration cycle device 1 of Embodiment 1 can appropriately heat the water to a temperature higher than the condensation temperature of the high-pressure gas phase refrigerant even when cooling sensible heat hot water supply operation is performed.

[0091] Furthermore, the refrigeration cycle device 1 of Embodiment 1 is further equipped with a second water-refrigerant heat exchanger 16. The refrigerant circuit switching valve 32 switches the refrigerant flow path so that the refrigerant does not flow through the second water-refrigerant heat exchanger 16 when heating sensible heat hot water supply operation is performed. The refrigerant circuit switching valve 32 also switches the refrigerant flow path so that the refrigerant is divided into a first refrigerant and a second refrigerant when heating total heat hot water supply operation is performed in which the indoor unit 3 heats the room and the water is heated by the second water-refrigerant heat exchanger 16. The first refrigerant releases heat to the water in the second water-refrigerant heat exchanger 16. The second refrigerant releases heat to the indoor air in the indoor heat exchanger 38. At this time, the refrigeration cycle device 1 of Embodiment 1 can appropriately heat the water to a temperature higher than the condensation temperature of the high-pressure gas-phase refrigerant, even when heating sensible heat hot water supply operation is performed.

[0092] Furthermore, the refrigeration cycle device 1 of Embodiment 1 further includes an inlet water temperature sensor 52 that measures the temperature of the water supplied to the first water-refrigerant heat exchanger 15 or the second water-refrigerant heat exchanger 16 as the inlet water temperature, and a control device 61 that controls the refrigerant circuit switching valve 32 based on the inlet water temperature. Here, when performing total heat hot water supply operation for cooling or total heat hot water supply operation for heating, whether the pressure of the refrigerant discharged from the compressor 31 increases depends on the inlet water temperature. Also, the hot water supply capacity or COP may decrease when performing sensible heat hot water supply operation for cooling or sensible heat hot water supply operation for heating compared to when performing total heat hot water supply operation for cooling or total heat hot water supply operation for heating. In this case, since the refrigeration cycle device 1 of Embodiment 1 controls the refrigerant circuit switching valve 32 based on the inlet water temperature, it is possible to suppress the unnecessary execution of sensible heat hot water supply operation for cooling or sensible heat hot water supply operation for heating, thereby improving energy efficiency.

[0093] Furthermore, the control device 61 of the refrigeration cycle device 1 in Example 1 calculates the target hot water outlet temperature based on the inlet water temperature, and controls the refrigerant circuit switching valve 32 so that the refrigerant flows through the first water refrigerant heat exchanger 15 and not through the second water refrigerant heat exchanger 16 when the target hot water outlet temperature is equal to or greater than the target hot water outlet temperature threshold. The control device 61 controls the refrigerant circuit switching valve 32 so that the refrigerant flows through the second water refrigerant heat exchanger 16 when the target hot water outlet temperature is less than the target hot water outlet temperature threshold. The refrigeration cycle device 1 in Example 1 can appropriately heat water to a high temperature while ensuring reliability and reducing power consumption by switching between sensible heat hot water supply operation and total heat hot water supply operation using the target hot water outlet temperature calculated based on the inlet water temperature.

[0094] Furthermore, the refrigeration cycle device 1 of Embodiment 1 is further equipped with a pump 12 and a hot water outlet temperature sensor 53. The pump 12 circulates water in the water circuit 6. The water circulating in the water circuit 6 is supplied from the outlet 21 of the hot water supply tank 11 provided in the water circuit 6 to the first water-refrigerant heat exchanger 15 or the second water-refrigerant heat exchanger 16, where it is heated and supplied to the hot water supply tank 11. The hot water outlet temperature sensor 53 measures the temperature of the heated water as the hot water outlet temperature. The control device 61 controls the pump 12 so that the hot water outlet temperature approaches the target hot water outlet temperature. The refrigeration cycle device 1 of Embodiment 1 can appropriately heat water to a high temperature while ensuring reliability and reducing power consumption by switching between sensible heat hot water supply operation and total heat hot water supply operation using the target hot water outlet temperature used in this way.

[0095] Furthermore, the heat transfer area of ​​the first water-refrigerant heat exchanger 15 in the refrigeration cycle device 1 of Example 1 is smaller than the heat transfer area of ​​the second water-refrigerant heat exchanger 16. Here, the required hot water supply capacity is smaller for cooling sensible heat hot water supply operation and heating sensible heat hot water supply operation compared to cooling total heat hot water supply operation, heating total heat hot water supply operation, or hot water supply only operation. In the refrigeration cycle device 1 of Example 1, since the heat transfer area of ​​the first water-refrigerant heat exchanger 15 used when cooling total heat hot water supply operation, heating total heat hot water supply operation, or hot water supply only operation is performed is smaller than the heat transfer area of ​​the second water-refrigerant heat exchanger 16, it is possible to ensure a hot water supply capacity that adequately heats water while suppressing costs.

[0096] By the way, in the refrigeration cycle device 1 of Embodiment 1 described above, when cooling total heat hot water supply operation, heating total heat hot water supply operation, or hot water supply only operation is performed, the high-pressure gaseous phase refrigerant does not flow through the first water refrigerant heat exchanger 15, but the high-pressure gaseous phase refrigerant may flow through the first water refrigerant heat exchanger 15. The refrigeration cycle device of Embodiment 2, as shown in Figure 7, is the same as the refrigeration cycle device 1 of Embodiment 1 described above, but the water circuit 6 is replaced with another water circuit 71. Figure 7 is a circuit diagram showing the refrigeration cycle device of Embodiment 2. The water circuit 71, like the water circuit 6 described above, includes a hot water tank 11, a pump 12, a first water refrigerant heat exchanger 15, a second water refrigerant heat exchanger 16, and a hot water tank inlet switching valve 18.

[0097] The water circuit 71 further includes a switching valve 72 and a water confluence section 73. The pump 12 is connected to the switching valve 72. The switching valve 72 is located inside the outdoor unit 2 and is connected to the second water-refrigerant heat exchanger 16 and the water confluence section 73. The second water-refrigerant heat exchanger 16 is connected to the water confluence section 73. The water confluence section 73 is connected to the first water-refrigerant heat exchanger 15. The first water-refrigerant heat exchanger 15 is connected to the hot water tank inlet switching valve 18.

[0098] The pump 12 of the water circuit 71 is not connected to the second water-refrigerant heat exchanger 16 when the refrigerant circuit 7 is switched to a cooling sensible heat hot water supply cycle or a heating sensible heat hot water supply cycle, but is connected to the first water-refrigerant heat exchanger 15 via a switching valve 72 and a water confluence section 73. The pump 12 of the water circuit 71 is not connected to the water confluence section 73 when the refrigerant circuit 7 is switched to a cooling total heat hot water supply cycle, a heating total heat hot water supply cycle, or a hot water supply-only cycle, but is connected to the second water-refrigerant heat exchanger 16 via a switching valve 72. The discharge pipe 42 of the refrigeration cycle device in Embodiment 2 is not connected to the refrigerant branch section 45 when the refrigerant circuit 7 is switched to a cooling total heat hot water supply cycle, a heating total heat hot water supply cycle, or a hot water supply-only cycle, but is connected to the first water-refrigerant heat exchanger 15 via a first solenoid valve 43.

[0099] When cooling sensible heat hot water supply operation or heating sensible heat hot water supply operation is performed, the low-temperature water flowing out of the hot water supply tank 11 of the water circuit 71 flows into the first water refrigerant heat exchanger 15 via the pump 12, the switching valve 72, and the water confluence section 73. The low-temperature water that flows into the first water refrigerant heat exchanger 15 is heated in the first water refrigerant heat exchanger 15. The low-temperature water heated in the first water refrigerant heat exchanger 15 becomes high-temperature water and flows into the hot water supply tank 11 via the hot water supply tank inlet switching valve 18. In other words, when cooling sensible heat hot water supply operation or heating sensible heat hot water supply operation is performed, the refrigeration cycle device of Embodiment 2 heats the low-temperature water using the sensible heat of the high-pressure gaseous refrigerant, similar to the refrigeration cycle device 1 of Embodiment 1 described above.

[0100] When cooling total heat hot water supply operation, heating total heat hot water supply operation, or hot water supply only operation is performed, the low-temperature water that flows out of the hot water tank 11 of the water circuit 71 flows into the second water refrigerant heat exchanger 16 via the pump 12 and the switching valve 72. The low-temperature water that flows into the second water refrigerant heat exchanger 16 is heated in the second water refrigerant heat exchanger 16, flows out of the second water refrigerant heat exchanger 16, flows into the first water refrigerant heat exchanger 15 via the water confluence section 73, and is heated in the first water refrigerant heat exchanger 15. The low-temperature water heated in the second water refrigerant heat exchanger 16 and the first water refrigerant heat exchanger 15 becomes high-temperature water and flows into the hot water tank 11 via the hot water tank inlet switching valve 18.

[0101] When cooling total heat hot water supply operation, heating total heat hot water supply operation, or hot water supply only operation is performed, the high-pressure gaseous refrigerant discharged from the compressor 31 flows into the first water refrigerant heat exchanger 15. The first water refrigerant heat exchanger 15 exchanges heat between the high-pressure gaseous refrigerant and the low-temperature water that has flowed into the first water refrigerant heat exchanger 15 via the water circuit 6, thereby cooling the high-pressure gaseous refrigerant. The high-pressure gaseous refrigerant does not condense in the first water refrigerant heat exchanger 15 and becomes post-heat dissipation refrigerant. The post-heat dissipation refrigerant flows out of the first water refrigerant heat exchanger 15 and flows into the second water refrigerant heat exchanger 16 via the refrigerant circuit switching valve 32. The second water refrigerant heat exchanger 16 exchanges heat between the post-heat dissipation refrigerant and the low-temperature water that has flowed into the second water refrigerant heat exchanger 16 via the water circuit 6, thereby cooling the post-heat dissipation refrigerant. The post-heat dissipation refrigerant is cooled by the second water refrigerant heat exchanger 16, condenses, and becomes high-pressure liquid phase refrigerant. In other words, the second water-refrigerant heat exchanger 16 functions as a condenser when the total heat supply operation for cooling is performed.

[0102] In other words, the refrigeration cycle device of Example 2 heats the low-temperature water using both the sensible heat and latent heat of the high-pressure gaseous refrigerant when cooling total heat hot water supply operation, heating total heat hot water supply operation, or hot water supply only operation is performed, similar to the refrigeration cycle device 1 of Example 1 described above. For this reason, the refrigeration cycle device of Example 2 can heat the low-temperature water to a high temperature while ensuring the reliability of the compressor 31 and reducing power consumption, similar to the refrigeration cycle device 1 of Example 1 described above.

[0103] By the way, the target hot water outlet temperature in the refrigeration cycle device of the embodiment described above is calculated to increase as the inlet water temperature increases, but it may be determined by other methods. For example, an inlet water temperature threshold may be set in advance, and the target hot water outlet temperature may be set to 45°C when the inlet water temperature is below the inlet water temperature threshold, and to 65°C when the inlet water temperature is equal to or greater than the inlet water temperature threshold. In this case as well, the refrigeration cycle device can appropriately switch between total heat hot water supply operation for cooling and sensible heat hot water supply operation for cooling, and can appropriately switch between total heat hot water supply operation for heating and sensible heat hot water supply operation for heating, similar to the refrigeration cycle device of the embodiment described above.

[0104] By the way, in the refrigeration cycle device of the embodiment described above, the pump 12 is controlled and the pump rotation speed is adjusted so that the hot water temperature measured by the hot water temperature sensor 53 approaches the target hot water temperature. However, in cooling sensible heat hot water supply operation and heating sensible heat hot water supply operation, the pump rotation speed may be adjusted based on other indicators. An example of such an indicator is the degree of superheating of the refrigerant after heat dissipation flowing out of the first water refrigerant heat exchanger 15. For example, the control device 61 obtains the discharge pressure measured by the discharge pressure sensor 54 from the discharge pressure sensor 54, and the temperature of the refrigerant after heat dissipation measured by the water heat exchanger outlet temperature sensor 55 from the water heat exchanger outlet temperature sensor 55. The control device 61 calculates the degree of superheating of the refrigerant after heat dissipation by subtracting the saturation temperature of the discharge pressure from the refrigerant temperature after heat dissipation. In other words, the discharge pressure sensor 54 and the water heat exchanger outlet temperature sensor 55 are superheating sensors. The control device 61 controls the pump 12 and adjusts the pump rotation speed so that the calculated superheating degree of the refrigerant after heat dissipation approaches the target superheating degree. An example of a target superheating degree is 2 degrees. In other words, the control device 61 decreases the pump rotation speed when the superheating degree of the refrigerant after heat dissipation is less than the target superheating degree, and increases the pump rotation speed when the superheating degree of the refrigerant after heat dissipation is greater than the target superheating degree.

[0105] If the refrigerant becomes a gas-liquid two-phase refrigerant after heat dissipation, liquid refrigerant may accumulate in the piping between the first water refrigerant heat exchanger 15 and the outdoor heat exchanger 33 or indoor heat exchanger 38. In this case, there is a risk of insufficient capacity due to a decrease in discharge pressure, or that the flow distribution balance of the multiple heat exchanger tubes installed in the outdoor heat exchanger 33 or indoor heat exchanger 38 may be disrupted, making them unusable. The refrigeration cycle system can more reliably prevent the refrigerant from becoming a gas-liquid two-phase refrigerant after heat dissipation by adjusting the pump rotation speed so that the superheating degree approaches the target superheating degree, thereby preventing refrigerant shortage and disruption of the flow distribution balance of the multiple heat exchanger tubes.

[0106] Incidentally, in the refrigeration cycle device described above, the flow rate of water circulating in the water circuit 6 is adjusted by adjusting the rotational speed of the pump 12, which acts as a flow rate control unit. However, the flow rate of water circulating in the water circuit 6 may also be adjusted by a flow rate control unit different from the pump 12. An example of another flow rate control unit is a flow rate control valve installed in the middle of the flow path of the water circuit 6. Even when the refrigeration cycle device adjusts the flow rate of water circulating in the water circuit 6 by adjusting the opening degree of the flow rate control valve, it is possible to bring the hot water temperature closer to the target hot water temperature and prevent the refrigerant from becoming a gas-liquid two-phase refrigerant after heat dissipation, similar to the refrigeration cycle device described above.

[0107] Incidentally, although the first water-refrigerant heat exchanger 15 and the second water-refrigerant heat exchanger 16 of the refrigeration cycle device described above are provided as separate heat exchangers, they may also be formed from a single heat exchanger. Even when the first water-refrigerant heat exchanger 15 and the second water-refrigerant heat exchanger 16 are formed from a single heat exchanger, the refrigeration cycle device can heat water while ensuring the reliability of the compressor 31 or reducing power consumption, similar to the refrigeration cycle device described above.

[0108] Although examples have been described above, the examples are not limited to those described above. Furthermore, the components described above include those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are equivalent. Moreover, the components described above can be combined as appropriate. Furthermore, at least one of the various omissions, substitutions, and modifications of the components can be made without departing from the gist of the examples.

[0109] 1: Refrigeration cycle unit 3: Indoor unit 5: Hot water supply unit 6: Water circuit 7: Refrigerant circuit 11: Hot water tank 12: Pump (flow control unit) 14: Switching valve 15: First water-refrigerant heat exchanger (water heat exchange section) 16: Second water-refrigerant heat exchanger (other water heat exchange section) 18: Hot water tank inlet switching valve 21: Outlet 32: Refrigerant circuit switching valve 33: Outdoor heat exchanger (air heat exchanger, heat source side heat exchanger) 38: Indoor heat exchanger (air heat exchanger, utilization side heat exchanger) 52: Inlet water temperature sensor 53: Outlet water temperature sensor 54: Discharge pressure sensor (superheat sensor) 55: Water heat exchanger outlet temperature sensor (superheat sensor) 61: Control device 71: Water circuit 72: Switching valve 73: Water confluence section

Claims

1. A refrigeration cycle device comprising: a refrigerant circuit through which a refrigerant circulates; an indoor unit that uses the heat of the refrigerant to heat and cool the room; a water circuit through which water circulates; a water heat exchange unit that exchanges heat between the refrigerant and the water so that the water is heated as the refrigerant releases heat; and an air heat exchanger that further releases heat from the refrigerant that has released heat in the water heat exchange unit when the water heat exchange unit heats the water while the indoor unit heats and cools the room.

2. The refrigeration cycle device according to claim 1, further comprising a refrigerant circuit switching valve that switches the refrigerant flow path through which the refrigerant circulates in the refrigerant circuit, wherein the air heat exchanger has a heat source side heat exchanger and a utilization side heat exchanger, and the refrigerant circuit switching valve switches the refrigerant flow path through which the refrigerant circulates in the refrigerant circuit so that the refrigerant dissipates heat in the heat source side heat exchanger when the indoor unit is performing a cooling sensible heat hot water supply operation in which the water is heated by the water heat exchanger, and switches the refrigerant flow path so that the refrigerant dissipates heat in the utilization side heat exchanger when the indoor unit is performing a heating sensible heat hot water supply operation in which the water is heated by the water heat exchanger, 3. The refrigeration cycle apparatus according to claim 2, further comprising another water heat exchange unit, wherein the refrigerant circuit switching valve switches the refrigerant flow path so that the refrigerant does not flow through the other water heat exchange unit when the cooling sensible heat hot water supply operation or the heating sensible heat hot water supply operation is performed, switches the refrigerant flow path so that the refrigerant flows through the other water heat exchange unit when the indoor unit cools the room and the water is heated by the other water heat exchange unit, and the other water heat exchange unit exchanges heat with the refrigerant and the water so that the water is heated by the refrigerant's heat release when the cooling total heat hot water supply operation is performed.

4. The refrigeration cycle device according to claim 2, further comprising another water heat exchange unit, wherein the refrigerant circuit switching valve switches the refrigerant flow path so that the refrigerant does not flow through the other water heat exchange unit when the cooling sensible heat hot water supply operation or the heating sensible heat hot water supply operation is performed, and switches the refrigerant flow path so that the refrigerant is divided into a first refrigerant and a second refrigerant when the indoor unit heats the room and the water is heated by the other water heat exchange unit in a total heat hot water supply operation, the first refrigerant releases heat to the water in the other water heat exchange unit, and the second refrigerant releases heat to the air in the room in the utilization-side heat exchanger.

5. The refrigeration cycle apparatus according to claim 3, further comprising: an inlet water temperature sensor that measures the temperature of the water supplied to the water heat exchange unit or the other water heat exchange unit as the inlet water temperature; and a control device that controls the refrigerant circuit switching valve based on the inlet water temperature.

6. The refrigeration cycle apparatus according to claim 5, wherein the control device calculates a target hot water outlet temperature based on the inlet water temperature, controls the refrigerant circuit switching valve so that the refrigerant flows through the water heat exchange section and not through the other water heat exchange section when the target hot water outlet temperature is equal to or greater than the target hot water outlet temperature threshold, and controls the refrigerant circuit switching valve so that the refrigerant flows through the other water heat exchange section when the target hot water outlet temperature is less than the target hot water outlet temperature threshold.

7. The refrigeration cycle apparatus according to claim 6, further comprising: a pump that circulates water in the water circuit so that water is supplied from the outlet of a hot water tank provided in the water circuit to the water heat exchange unit or the other water heat exchange unit, and the water heated in the water heat exchange unit or the other water heat exchange unit is supplied to the hot water tank; and a hot water temperature sensor that measures the temperature of the heated water as the hot water outlet temperature, wherein the control device controls the pump so that the hot water outlet temperature approaches the target hot water outlet temperature.

8. The refrigeration cycle apparatus according to claim 1, further comprising: a flow control unit provided in the water circuit for controlling the flow rate of water circulating in the water circuit; a superheat sensor for measuring the degree of superheating of the refrigerant after heat dissipation; and a control device for controlling the flow control unit so that the degree of superheating approaches a target degree of superheating.

9. The refrigeration cycle apparatus according to claim 3, wherein the heat transfer area of ​​the water heat exchange section is smaller than the heat transfer area of ​​the other water heat exchange sections.

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