Air conditioning hot water system and control method and control device of the same

Abstract

To provide an art which continues operation of a hot water supply unit when a refrigerant leaks in an indoor unit.SOLUTION: An air conditioning hot water system includes: an outdoor unit which includes a compressor configured to compress a first heat medium and supplies the first heat medium; a hot water supply unit which generates hot water by using the first heat medium supplied from the outdoor unit; an indoor unit which performs air conditioning by using the first heat medium supplied from the outdoor unit; a blocking unit which blocks the first heat medium flowing in the indoor unit; and a control unit which exercises control to cause the blocking unit to block the first heat medium flowing in the indoor unit, continue operation of the compressor, and continue supply of the first heat medium from the outdoor unit to the hot water supply unit when the first heat medium leaks in the indoor unit.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an air conditioning and hot water supply system, and a control method and control device for the air conditioning and hot water supply system. [Background technology]

[0002] Patent document 1 discloses an air conditioning and hot water system comprising an outdoor unit, a number of indoor units each connected to the outdoor unit, and a hot water unit connected to the outdoor unit so as to be arranged in parallel with the number of indoor units.

[0003] Patent Document 2 discloses an air conditioner in which an outdoor unit and multiple indoor units are connected by refrigerant piping. Patent Document 2 discloses that an externally attached device is provided with an expansion valve provided on one side of multiple refrigerant piping that connects the indoor unit and the outdoor unit, and a solenoid valve provided on the other side, and that the expansion valve and the solenoid valve are closed in the event of a refrigerant leak. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2019-529857 [Patent Document 2] JP 2012-013339 A Summary of the Invention [Problem to be solved by the invention]

[0005] 2. Description of the Related Art In an air conditioning and hot water supply system that performs air conditioning and hot water supply, it is required to continue the hot water supply function in the event of a refrigerant leak in an indoor unit.

[0006] The present disclosure provides a technique for continuing operation of a hot water supply unit when a refrigerant leaks in an indoor unit. [Means for solving the problem]

[0007] The first aspect of the air conditioning and hot water supply system is an outdoor unit including a compressor that compresses a first heat medium and supplies the first heat medium; a hot water supply unit that generates hot water using the first heat medium supplied from the outdoor unit; an indoor unit that performs air conditioning using the first heat medium supplied from the outdoor unit; a blocking unit that blocks the first heat medium flowing into the indoor unit; a control unit that, when the first heat medium leaks from the indoor unit, controls the blocking unit to block the first heat medium flowing to the indoor unit, continues operation of the compressor, and continues supply of the first heat medium from the outdoor unit to the hot water supply unit; Equipped with It is an air conditioning and hot water system.

[0008] According to the air conditioning and hot water supply system of the first aspect, when a refrigerant leaks in the indoor unit, the operation of the hot water supply unit can be continued.

[0009] The second aspect of the air conditioning and hot water supply system is The hot water supply unit includes a cascade heat medium circuit that generates hot water using a second heat medium that has exchanged heat with the first heat medium. This is an air conditioning and hot water supply system from a first perspective.

[0010] The third perspective of the air conditioning and hot water supply system is The cascade heat medium circuit continues circulation of the second heat medium when the first heat medium leaks in the indoor unit. This is an air conditioning and hot water supply system from the second perspective.

[0011] The fourth perspective of the air conditioning and hot water supply system is The first heat medium is R32, The second heat transfer medium is 1234yf; The air conditioning and hot water supply system according to the second or third aspect.

[0012] The fifth aspect of the air conditioning and hot water supply system is The indoor unit includes an expansion valve, The expansion valve functions as a shutoff valve in the shutoff unit. The air conditioning and hot water supply system according to any one of the first aspect to the fifth aspect.

[0013] The sixth aspect of the air conditioning and hot water supply system is After the shutoff unit is shut off, the amount m of the first heat medium discharged from the indoor unit satisfies Formula 1. The air conditioning and hot water supply system according to any one of the first aspect to the fifth aspect.

[0014]

number

[0015]

number

[0016] The seventh aspect of the air conditioning and hot water supply system is A plurality of the indoor units are provided, and a plurality of the shutoff units are provided for each of the indoor units, The control unit controls the blocking unit in the indoor unit in which the first heat medium has leaked to block the first heat medium, and to continue supplying the first heat medium to the indoor units other than the indoor unit in which the first heat medium has leaked. The air conditioning and hot water supply system according to any one of the first aspect to the sixth aspect.

[0017] The eighth aspect of the air conditioning and hot water supply system is The first heat medium is a slightly flammable refrigerant or a flammable refrigerant. The air conditioning and hot water supply system according to any one of the first aspect to the seventh aspect.

[0018] The ninth aspect of the air conditioning and hot water supply system is The first heat medium is R32. The air conditioning and hot water supply system according to any one of the first aspect to the eighth aspect.

[0019] The 10th aspect of the air conditioning and hot water supply system is When the capacity of the indoor unit with the shutoff unit closed is equal to or greater than a predetermined capacity relative to the capacity of the outdoor unit, the operation of the compressor is stopped. The air conditioning and hot water supply system according to any one of the first aspect to the ninth aspect.

[0020] A control method for an air conditioning and hot water supply system according to a first aspect of the present invention comprises: an outdoor unit including a compressor that compresses a first heat medium and supplies the first heat medium; a hot water supply unit that generates hot water using the first heat medium supplied from the outdoor unit; an indoor unit that performs air conditioning using the first heat medium supplied from the outdoor unit; a blocking unit that blocks the first heat medium flowing into the indoor unit; A control method for an air conditioning and hot water supply system comprising: When the first heat medium leaks from the indoor unit, the blocking unit blocks the first heat medium flowing to the indoor unit, and the compressor continues to operate, thereby continuing the supply of the first heat medium from the outdoor unit to the hot water supply unit. A control method for an air conditioning and hot water supply system.

[0021] According to the control method for an air conditioning and hot water supply system of the first aspect, when a refrigerant leaks in the indoor unit, the hot water supply function can be continued.

[0022] A control device according to a first aspect of the present invention comprises: an outdoor unit including a compressor that compresses a first heat medium and supplies the first heat medium; a hot water supply unit that generates hot water using the first heat medium supplied from the outdoor unit; an indoor unit that performs air conditioning using the first heat medium supplied from the outdoor unit; a blocking unit that blocks the first heat medium flowing into the indoor unit; A control device for use in an air conditioning and hot water supply system comprising: When the first heat medium leaks from the indoor unit, the blocking unit blocks the first heat medium flowing to the indoor unit, and the compressor continues to operate, so that the supply of the first heat medium from the outdoor unit to the hot water supply unit is continued. It is a control device.

[0023] According to the control device of the first aspect, when refrigerant leaks in the indoor unit, the hot water supply function can be continued. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a diagram showing an outline of the configuration of an air conditioning and hot water supply system according to a first embodiment. [Diagram 2] FIG. 2 is a diagram showing an overview of the outdoor unit provided in the air conditioning and hot water supply system according to the first embodiment. [Diagram 3] FIG. 3 is a diagram showing an overview of a hot water supply unit provided in the air conditioning and hot water supply system according to the first embodiment. [Figure 4] FIG. 4 is a diagram showing an overview of the indoor unit and the shutoff unit provided in the air conditioning and hot water supply system according to the first embodiment. [Diagram 5] FIG. 5 is a diagram showing a hardware configuration of a control unit provided in the air conditioning and hot water supply system according to the first embodiment. [Figure 6] FIG. 6 is a diagram showing an overview of the cooling / heating switching unit included in the air conditioning and hot water supply system according to the first embodiment. [Figure 7] FIG. 7 is a flow diagram showing the process of the air conditioning and hot water supply system according to the first embodiment. [Figure 8] FIG. 8 is a diagram showing an outline of the configuration of an air conditioning and hot water supply system according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Hereinafter, the embodiments will be described with reference to the accompanying drawings. In the description of the specification and drawings relating to each embodiment, components having substantially the same or corresponding functional configurations may be denoted by the same reference numerals to avoid redundant description. In addition, the scale of each part in the drawings may differ from the actual scale in order to facilitate understanding.

[0026] First Embodiment An air conditioning and hot water supply system according to the first embodiment will be described. The air conditioning and hot water supply system according to the first embodiment includes an outdoor unit, a hot water supply unit, an indoor unit, a shutoff unit, and a control unit. The outdoor unit in the air conditioning and hot water supply system according to the first embodiment includes a compressor that compresses a first heat medium and supplies the first heat medium. The hot water supply unit in the air conditioning and hot water supply system according to the first embodiment generates hot water using the first heat medium supplied from the outdoor unit. The indoor unit in the air conditioning and hot water supply system according to the first embodiment performs air conditioning using the first heat medium supplied from the outdoor unit. The shutoff unit in the air conditioning and hot water supply system according to the first embodiment shuts off the first heat medium flowing to the indoor unit. The control unit in the air conditioning and hot water supply system according to the first embodiment controls the shutoff unit to shut off the first heat medium flowing to the indoor unit when the first heat medium leaks from the indoor unit. In addition, when the first heat medium leaks in the indoor unit, the control unit in the air conditioning and hot water supply system of the first embodiment controls the compressor to continue operating and to continue the supply of the first heat medium from the outdoor unit to the hot water supply unit.

[0027] FIG. 1 is a diagram showing an outline of the configuration of an air conditioning and hot water supply system 1, which is an example of the air conditioning and hot water supply system according to the first embodiment.

[0028] [Air conditioning and hot water system 1] The air conditioning and hot water supply system 1 generates hot water (hot water supply) and conditions a specified space. The air conditioning and hot water supply system 1 is a so-called heat pump type air conditioning and hot water supply system. The air conditioning and hot water supply system 1 can, for example, supply hot water while heating and supply hot water while cooling.

[0029] The air conditioning and hot water supply system 1 includes an outdoor unit 10, a hot water supply unit 20, an indoor unit 30, a shutoff unit 40, and a control unit 50. The air conditioning and hot water supply system 1 also includes a cooling / heating switching unit 60a between the outdoor unit 10 and the hot water supply unit 20. The air conditioning and hot water supply system 1 also includes a cooling / heating switching unit 60b between the outdoor unit 10 and the indoor unit 30. Each of the components included in the air conditioning and hot water supply system 1 will be described in detail.

[0030] (Outdoor unit 10) A detailed description will now be given of the outdoor unit 10. Fig. 2 is a diagram showing an overview of the outdoor unit 10 provided in the air conditioning and hot water supply system 1, which is an example of the air conditioning and hot water supply system according to the first embodiment.

[0031] The outdoor unit 10 supplies a first heat medium RF1 to each of the hot water supply unit 20 and the indoor unit 30. The outdoor unit 10 is installed outdoors, for example, on the rooftop or balcony of a building. The outdoor unit 10 is also installed underground, for example. The outdoor unit 10 uses, for example, R32, which is an alternative refrigerant, as the first heat medium RF1. The outdoor unit 10 may use, for example, propane as the first heat medium RF1. Also, R454B may be used as the first heat medium RF1.

[0032] R32 is a slightly flammable refrigerant. Propane is a flammable refrigerant.

[0033] The outdoor unit 10 includes a compressor 11, an accumulator 12, heat exchangers 13a and 13b, expansion valves 14a and 14b, four-way switching valves 15a, 15b and 15c, and a fan 16.

[0034] The compressor 11 compresses the first heat medium RF1. The compressor 11 is, for example, a scroll or rotary type positive displacement compressor having a sealed structure with a compressor motor built in. The compressor 11 compresses the low-pressure first heat medium RF1 that is sucked in. Then, the compressor 11 discharges the compressed first heat medium RF1.

[0035] The accumulator 12 temporarily stores the low-pressure first heat medium RF1 sucked into the compressor 11. The accumulator 12 temporarily stores the first heat medium RF1, thereby separating the first heat medium RF1 into gas and liquid.

[0036] Each of the heat exchangers 13a and 13b exchanges heat between the first heat medium RF1 and the outside air. Each of the heat exchangers 13a and 13b is, for example, a cross-fin type or a microchannel type heat exchanger.

[0037] Each of the expansion valves 14a and 14b reduces the pressure of the first heat medium RF1 passing therethrough. Each of the expansion valves 14a and 14b is, for example, an electrically operated valve whose opening degree is adjustable.

[0038] The four-way switching valve 15a, the four-way switching valve 15b, and the four-way switching valve 15c each switch the flow of the first heat medium RF1. Each of the four-way switching valve 15a, the four-way switching valve 15b, and the four-way switching valve 15c essentially functions as a three-way valve because one of the flow paths is blocked.

[0039] The fan 16 generates a flow of air that flows through the heat exchanger 13a and the heat exchanger 13b. The fan 16 is, for example, an axial flow fan.

[0040] The outdoor unit 10 is connected to a liquid connection pipe RL1, an intake gas connection pipe RL2, and a high and low pressure gas connection pipe RL3.

[0041] The air conditioning and hot water supply system 1 produces hot water in the hot water supply unit 20, and performs heating and cooling operations in the indoor unit 30. The operation of the outdoor unit 10 when the indoor unit 30 performs each of the heating operation and the cooling operation will be described.

[0042] (1) Heating operation When the indoor unit 30 performs heating operation, the first heat medium RF1 compressed in the compressor 11 passes through the four-way switching valve 15c and is discharged from the high and low pressure gas communication pipe RL3.

[0043] The first heat medium RF1 returning from the liquid connection pipe RL1 branches to flow to each of the expansion valve 14a and the expansion valve 14b. The first heat medium RF1 branched to the expansion valve 14a side is depressurized when passing through the expansion valve 14a. The first heat medium RF1 depressurized in the expansion valve 14a exchanges heat with the outdoor air and evaporates when passing through the heat exchanger 13a. The first heat medium RF1 evaporated in the heat exchanger 13a passes through the four-way switching valve 15a and the accumulator 12 and is sucked into the compressor 11. Similarly, the first heat medium RF1 branched to the expansion valve 14b side is depressurized when passing through the expansion valve 14b. The first heat medium RF1 depressurized in the expansion valve 14b exchanges heat with the outdoor air and evaporates when passing through the heat exchanger 13b. Then, the first heat medium RF1 evaporated in the heat exchanger 13a passes through the four-way selector valve 15b and the accumulator 12, and is sucked into the compressor 11.

[0044] (2) Cooling operation (cooling + hot water) When the indoor unit 30 performs cooling operation, the first heat medium RF1 compressed in the compressor 11 is branched to flow to each of the four-way switching valve 15a and the four-way switching valve 15c. The first heat medium RF1 branched to the four-way switching valve 15a side exchanges heat with the outdoor air in the heat exchanger 13a and is condensed. The first heat medium RF1 condensed in the heat exchanger 13a passes through the expansion valve 14a and is discharged from the liquid connection pipe RL1. The first heat medium RF1 branched to the four-way switching valve 15c is discharged from the high-low pressure gas connection pipe RL3.

[0045] The first heat medium RF1 returning from the intake gas communication pipe RL2 passes through the accumulator 12 and is sucked into the compressor 11.

[0046] (Hot water unit 20) The hot water supply unit 20 uses the first heat medium RF1 supplied from the outdoor unit 10 to generate hot water.

[0047] FIG. 3 is a diagram showing an overview of a hot water supply unit 20 provided in an air conditioning and hot water supply system 1, which is an example of the air conditioning and hot water supply system according to the first embodiment.

[0048] The hot water supply unit 20 includes a cascade heat medium circuit 20s using the second heat medium RF2 that has exchanged heat with the first heat medium RF1. The cascade heat medium circuit 20s produces hot water.

[0049] The hot water supply unit 20 is integrated with the outdoor unit 10, for example. The hot water supply unit 20 integrated with the outdoor unit 10 is installed outdoors, for example, on the rooftop or balcony of a building. The hot water supply unit 20 is installed underground, for example. The hot water supply unit 20 uses, for example, 1234yf, which is an alternative fluorocarbon, as the second heat medium RF2. 1234yf is a slightly flammable refrigerant (slightly flammable refrigerant). Note that 1234ze may be used as the second heat medium RF2. The combination of the first heat medium RF1 and the second heat medium RF is not limited to the combination of R32 and 1234yf, and may be, for example, any of the combinations of R454B and 1234yf, RF454B and 1234ze, and R32 and 1234ze.

[0050] The hot water supply unit 20 includes a compressor 21, an accumulator 22, a heat exchanger 23, a heat exchanger 24, an expansion valve 25, an expansion valve 26, a pump 27, a four-way switching valve 28, a check valve 29a, and a check valve 29b.

[0051] The compressor 21 compresses the second heat medium RF2. The compressor 21 is, for example, a scroll or rotary type positive displacement compressor having a sealed structure with a compressor motor built in. The compressor 21 compresses the low pressure second heat medium RF2 that is sucked in. Then, the compressor 21 discharges the compressed second heat medium RF2.

[0052] The accumulator 22 temporarily stores the low-pressure second heat medium RF2 sucked into the compressor 21. The accumulator 22 temporarily stores the second heat medium RF2, thereby separating the second heat medium RF2 into gas and liquid.

[0053] The heat exchanger 23 exchanges heat between the first heat medium RF1 and the second heat medium RF2. The heat exchanger 23 is, for example, a plate-type or spiral-type heat exchanger.

[0054] The heat exchanger 24 exchanges heat between the second heat medium RF2 and water. The heat exchanger 24 is, for example, a double-pipe heat exchanger.

[0055] The expansion valve 25 reduces the pressure of the first heat medium RF1 passing therethrough. The expansion valve 26 reduces the pressure of the second heat medium RF2 passing therethrough. Each of the expansion valves 25 and 26 is, for example, a motor-operated valve whose opening degree is adjustable.

[0056] Pump 27 pumps water through heat exchanger 24 .

[0057] The four-way switching valve 28 switches the flow of the second heat medium RF2.

[0058] The check valve 29a prevents the second heat medium RF2 from flowing back to the compressor 21. The check valve 29b prevents water from flowing back.

[0059] (Indoor unit 30) The indoor unit 30 conditions the air in a predetermined space RM.

[0060] FIG. 4 is a diagram showing an overview of an indoor unit 30 and a shutoff unit 40 provided in an air conditioning and hot water supply system 1, which is an example of the air conditioning and hot water supply system according to the first embodiment.

[0061] The indoor unit 30 includes a heat exchanger 31, an expansion valve 32, a detector 33, and a fan .

[0062] The heat exchanger 31 exchanges heat between the first heat medium RF1 and air. The heat exchanger 31 is, for example, a cross-fin type or a microchannel type heat exchanger.

[0063] The expansion valve 32 reduces the pressure of the first heat medium RF1 passing through the inside of the expansion valve 32. The expansion valve 32 is, for example, an electrically operated valve whose opening degree is adjustable.

[0064] The detector 33 detects the first heat medium RF1. The detector 33 detects the first heat medium RF1, thereby detecting leakage of the first heat medium RF1.

[0065] The fan 34 generates an air flow that passes through the heat exchanger 31. The fan 34 is, for example, a sirocco fan.

[0066] (Breaking unit 40) The cutoff unit 40 cuts off the first heat medium RF1 flowing from the outdoor unit 10 to the indoor unit 30.

[0067] The shutoff unit 40 includes a shutoff valve 41 and a shutoff valve 42. Each of the shutoff valve 41 and the shutoff valve 42 is, for example, a motor-operated valve.

[0068] For example, when the detector 33 included in the indoor unit 30 detects leakage of the first heat medium RF1, the shutoff unit 40 closes the shutoff valve 41 and the shutoff valve 42. Then, the shutoff unit 40 cuts off the supply of the first heat medium RF1 to the indoor unit 30.

[0069] The amount of the first heat medium RF1 discharged from the indoor unit 30 after the shutoff unit 40 is shut off will be described. In other words, the amount of the first heat medium RF1 remaining on the indoor unit 30 side from the shutoff unit 40 will be described after the shutoff unit 40 is shut off.

[0070] It is desirable that the amount m of the first heat medium RF1 discharged from the indoor unit 30 after the shutoff unit 40 is shut off satisfies formula A.

[0071]

number

[0072] where max(a,b) is a function that returns the larger of a and b, and min(a,b) is a function that returns the smaller of a and b. LFL is the lower flammability limit of the first heat medium RF1 (unit: kilograms per cubic meter (kg / m 3 When the first heat medium RF1 is R32, the LFL is, for example, 0.307 kilograms per cubic meter (kg / m 3 ) A is the minimum room area (unit: square meters (m 2 )), h0 is the floor height (unit: meters (m)), and SF is a constant (0.5). The floor height h0 is calculated based on formula D.

[0073]

number

[0074] However, h inst is the height of the bottom surface of the product from the floor, h rel is the height from the base of the product of an opening that has a cumulative open area of ​​5 square centimeters from the base (excluding holes with dimensions of 0.1 millimeters or less).

[0075] (Control unit 50) The control unit 50 controls the outdoor unit 10, the hot water supply unit 20, the indoor unit 30, the cooling / heating switching unit 60a, and the cooling / heating switching unit 60b. Fig. 5 is a hardware configuration diagram showing the hardware configuration of the control unit 50 provided in the air conditioning and hot water supply system 1, which is an example of the air conditioning and hot water supply system according to the first embodiment.

[0076] The control unit 50 includes a control unit 51, a RAM (Random Access Memory) 52, and a ROM (Read Only Memory) 53. The control unit 50 also includes a storage I / F (Interface) 54 and an external I / F 55. Each of the control unit 51, the RAM 52, the ROM 53, the storage I / F 54, and the external I / F 55 is connected to a bus B1.

[0077] For example, a storage medium 54a is connected to the storage I / F 54. For example, the outdoor unit 10, the hot water supply unit 20, the indoor unit 30, the cooling / heating switching unit 60a, and the cooling / heating switching unit 60b are connected to the external I / F 55.

[0078] The control unit 51 is a processor such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). The control unit 51 may be an ASIC (application specific integrated circuit) or an FPGA (Field-Programmable Gate Array). The control unit 51 executes a program to perform each process described in this specification. The control unit 51 is a calculation device that reads a program (app, application) from a storage device such as ROM 53 or storage medium 54a onto RAM 52 and executes the process. The control unit 51, RAM 52, and ROM 53 constitute a computer that controls the air conditioning and hot water supply system 1.

[0079] The RAM 52 is a volatile semiconductor memory that temporarily stores, for example, programs (applications) and the like.

[0080] The ROM 53 is, for example, a non-volatile semiconductor memory that can hold programs (apps, applications) even when the power is turned off. The ROM 53 stores programs such as a BIOS (Basic Input / Output System) that is executed at startup, and various settings such as OS (Operating System) settings and network settings.

[0081] The storage I / F 54 is an interface with an external storage device such as a storage medium 54a.

[0082] The storage medium 54a is, for example, a Secure Digital (SD) memory card, a Universal Serial Bus (USB) memory, a Hard Disk Drive (HDD), or a Solid State Drive (SSD).

[0083] The external I / F 36 is an interface that connects peripheral devices to the control unit 51. Through the external I / F 36, the control unit 51 is connected to each of the outdoor unit 10, the hot water supply unit 20, the indoor unit 30, the cooling / heating switching unit 60a, and the cooling / heating switching unit 60b.

[0084] (Cooling / heating switching unit 60a and cooling / heating switching unit 60b) Each of the cooling / heating switching units 60a and 60b controls the flow path through which the first heat medium RF1 flows so as to, for example, perform cooling, heating, and hot water supply simultaneously.

[0085] 6 is a diagram showing an overview of a cooling / heating switching unit 60 provided in an air conditioning / hot water supply system 1, which is an example of the air conditioning / hot water supply system according to the first embodiment. Since the cooling / heating switching unit 60a and the cooling / heating switching unit 60b have the same configuration, the cooling / heating switching unit 60a and the cooling / heating switching unit 60b will be described using the cooling / heating switching unit 60.

[0086] The cooling / heating switching unit 60 includes a heat exchanger 61 , a control valve 62 , a control valve 63 , and a control valve 64 .

[0087] The operation of the cooling / heating switching unit 60 in the indoor unit 30 when performing heating operation and cooling operation will be described.

[0088] (1) Heating operation When the indoor unit 30 performs heating operation, in the cooling / heating switching unit 60 connected to each of the hot water supply unit 20 and the indoor unit 30, the control valve 63 connected to the high and low pressure gas connection pipe RL3 is opened. Also, the control valves 62 and 64 are closed. By opening the control valve 63 and closing the control valves 62 and 64, the first heat medium RF1 flowing in from the high and low pressure gas connection pipe RL3 flows out to the pipe PL2, and the first heat medium RF1 flowing in from the pipe PL1 flows out to the liquid connection pipe RL1.

[0089] (2) Cooling operation (cooling + hot water) When the indoor unit 30 performs cooling operation, in the cooling / heating switching unit 60 connected to the hot water supply unit 20, the control valve 63 connected to the high and low pressure gas connection pipe RL3 is opened, and the control valves 62 and 64 are closed. By opening the control valve 63 and closing the control valves 62 and 64, the first heat medium RF1 flowing in from the high and low pressure gas connection pipe RL3 flows out to the pipe PL2, and the first heat medium RF1 flowing in from the pipe PL1 flows out to the liquid connection pipe RL1.

[0090] In the cooling / heating switching unit 60 connected to the indoor unit 30, the control valve 64 connected to the intake gas connection pipe RL2 is opened. The control valves 62 and 63 are closed. By opening the control valve 64 and closing the control valves 62 and 63, the first heat medium RF1 flowing in from the liquid connection pipe RL1 flows out to the pipe PL1, and the first heat medium RF1 flowing in from the pipe PL2 flows out to the intake gas connection pipe RL2.

[0091] <Processing in the air conditioning and hot water supply system according to the first embodiment> The processing in the air conditioning and hot water supply system according to the first embodiment will be described. The processing will be described using air conditioning and hot water supply system 1, which is an example of the air conditioning and hot water supply system according to the first embodiment. More specifically, the processing in control unit 51 of control unit 50 provided in air conditioning and hot water supply system 1 will be described. By explaining the processing in control unit 51 of control unit 50 provided in air conditioning and hot water supply system 1, a control method for the air conditioning and hot water supply system according to this embodiment will be described.

[0092] FIG. 7 is a flow diagram showing the process of the air conditioning and hot water supply system 1, which is an example of the air conditioning and hot water supply system according to the first embodiment.

[0093] (Step S10) First, the control unit 51 detects whether or not there is a leakage of the first heat medium RF1 in the indoor unit 30 (heat medium leakage detection step). Specifically, the control unit 51 obtains information on whether or not the detector 33 in the indoor unit 30 has detected the first heat medium RF1.

[0094] (Step S20) Next, the control unit 51 determines whether or not the first heat medium RF1 is leaking in the indoor unit 30 based on the detection result in step S10. Specifically, when the detector 33 in the indoor unit 30 detects the first heat medium RF1, the control unit 51 determines that the first heat medium RF1 is leaking in the indoor unit 30. On the other hand, when the detector 33 in the indoor unit 30 does not detect the first heat medium RF1, the control unit 51 determines that the first heat medium RF1 is not leaking in the indoor unit 30.

[0095] In step S20, if it is determined that the first heat medium RF1 is leaking from the indoor unit 30 (YES in step S20), the control unit 51 proceeds to step S30. In step S20, if it is determined that the first heat medium RF1 is not leaking from the indoor unit 30 (NO in step S20), the control unit 51 returns to step S10 and repeats the process.

[0096] (Step S30) When it is determined that the first heat medium RF1 is leaking from the indoor unit 30 (YES in step S20), the control unit 51 shuts off the flow of the first heat medium RF1 to the indoor unit 30 by the shutoff unit 40 (shutoff step). Specifically, the control unit 51 closes each of the shutoff valves 41 and 42 provided in the shutoff unit 40 to stop the supply of the first heat medium RF1 to the indoor unit 30.

[0097] At the time of step S30, the operation of the compressor 11 in the outdoor unit 10 continues. The outdoor unit 10 continues to supply the first heat medium RF1 to the hot water supply unit 20. The second heat medium RF2 also continues to circulate in the hot water supply unit 20. Since the supply of the first heat medium RF1 to the hot water supply unit 20 continues, the air conditioning and hot water supply system 1 can continue to supply hot water.

[0098] In the above example, the control unit 51 closes each of the shutoff valves 41 and 42 provided in the shutoff unit 40, but the control unit 51 may close the expansion valve 32 provided in the indoor unit 30. When the expansion valve 32 is closed, the shutoff valve 42 in the shutoff unit 40 may or may not be provided.

[0099] (Step S40) Next, the control unit 51 determines whether the capacity of the indoor unit 30 that has stopped the supply of the first heat medium RF1 is equal to or greater than a predetermined capacity (capacity determination step). Specifically, the control unit 51 acquires the capacity of the indoor unit 30 that has shut off the first heat medium RF1 by the shutoff unit 40. Then, the control unit 51 determines whether the capacity of the indoor unit 30 that has shut off the first heat medium RF1 by the shutoff unit 40 is equal to or greater than a predetermined capacity.

[0100] The predetermined capacity may be appropriately determined so as to protect the compressor 11 in the outdoor unit 10. The predetermined capacity is, for example, 50% of the capacity of the outdoor unit 10. Note that the predetermined capacity may be, for example, any one of 20, 25, 30, and 40% of the capacity of the outdoor unit 10.

[0101] In step S40, if it is determined that the capacity of the indoor unit 30 that has stopped the supply of the first heat medium RF1 is equal to or greater than a predetermined capacity (YES in step S40), the control unit 51 proceeds to step S50. In step S40, if it is determined that the capacity of the indoor unit 30 that has stopped the supply of the first heat medium RF1 is less than the predetermined capacity (NO in step S40), the control unit 51 ends the process.

[0102] (Step S50) In step S40, when it is determined that the capacity of the indoor unit 30 to which the supply of the first heat medium RF1 has been stopped is equal to or greater than a predetermined capacity (YES in step S40), the control unit 51 stops the operation of the compressor 11 in the outdoor unit 10 (compressor stopping step). After stopping the operation of the compressor 11, the control unit 51 ends the process.

[0103] According to the air conditioning and hot water supply system of the first embodiment, the hot water supply function can be continued even if a refrigerant leaks in the indoor unit. In the air conditioning and hot water supply system of the first embodiment, when the first heat medium leaks in the indoor unit, the shutoff unit shuts off the first heat medium flowing to the indoor unit. Furthermore, in the air conditioning and hot water supply system of the first embodiment, when the first heat medium leaks in the indoor unit, the compressor continues to operate and the supply of the first heat medium from the outdoor unit to the hot water supply unit continues. Thus, according to the air conditioning and hot water supply system of the first embodiment, the hot water supply function can be continued even if a refrigerant leaks in the indoor unit.

[0104] Although an example of the air conditioning and hot water supply system 1, which is an example of the air conditioning and hot water supply system according to the first embodiment, has been described with one indoor unit 30, the air conditioning and hot water supply system according to the first embodiment may include multiple indoor units. All of the multiple indoor units included in the air conditioning and hot water supply system according to the first embodiment may be equipped with a shutoff unit, or at least one indoor unit may be equipped with a shutoff unit.

[0105] When multiple indoor units are provided, all of the multiple indoor units may be in heating operation or cooling operation, or some of the multiple indoor units may be in heating operation and some in cooling operation.

[0106] Also, in the air-conditioning and hot water supply system 1, which is an example of the air-conditioning and hot water supply system according to the first embodiment, an example of control by the control unit 51 has been described, but in the air-conditioning and hot water supply system according to the first embodiment, the function of the control unit is not limited to being realized by the control unit 51. The function of the control unit in the air-conditioning and hot water supply system according to the first embodiment may be realized, for example, by any of the control units included in each of the outdoor unit, the hot water supply unit, the indoor unit, and the shutoff unit included in the air-conditioning and hot water supply system according to the first embodiment, or may be realized by the interlocking of the respective control units. Similarly, for example, the function may be realized by a control unit included in the cooling / heating switching unit 60 in the air-conditioning and hot water supply system 1, which is an example of the air-conditioning and hot water supply system according to the first embodiment.

[0107] Furthermore, the control unit in the air conditioning and hot water supply system according to the first embodiment may be provided separately as a control device used in the air conditioning and hot water supply system. In other words, it may be a control device used in an air conditioning and hot water supply system including an outdoor unit, a hot water supply unit, an indoor unit, and a shutoff unit in the air conditioning and hot water supply system according to the first embodiment. Then, when the first heat medium leaks in the indoor unit, the control device may control the shutoff unit to shut off the first heat medium flowing to the indoor unit. Also, when the first heat medium leaks in the indoor unit, the control device may control the compressor to continue operating and to continue the supply of the first heat medium from the outdoor unit to the hot water supply unit.

[0108] Second Embodiment The air conditioning and hot water supply system according to the second embodiment includes a plurality of indoor units. Moreover, the air conditioning and hot water supply system according to the second embodiment includes a shutoff unit in each of the plurality of indoor units. In other words, the air conditioning and hot water supply system according to the second embodiment includes a plurality of shutoff units, one for each indoor unit. Then, the control unit in the air conditioning and hot water supply system according to the second embodiment shuts off the first heat medium using the shutoff unit in the indoor unit in which the first heat medium has leaked, and controls the supply of the first heat medium to indoor units other than the indoor unit in which the first heat medium has leaked to continue.

[0109] FIG. 8 is a diagram showing an outline of the configuration of an air conditioning and hot water supply system 2, which is an example of an air conditioning and hot water supply system according to the second embodiment.

[0110] The air conditioning and hot water supply system 2 includes an indoor unit 30A and an indoor unit 30B. In other words, the air conditioning and hot water supply system 2 includes two indoor units. The air conditioning and hot water supply system 2 includes a shutoff unit 40A that shuts off the flow of the first heat medium RF1 to the indoor unit 30A when the first heat medium RF1 leaks from the indoor unit 30A. The air conditioning and hot water supply system 2 also includes a shutoff unit 40B that shuts off the flow of the first heat medium RF1 to the indoor unit 30B when the first heat medium RF1 leaks from the indoor unit 30B.

[0111] The air conditioning and hot water supply system 2 includes a control unit 150 instead of the control unit 50 in the air conditioning and hot water supply system 1. The control unit 150 has the functions of the control unit 50 and also controls each of the shutoff unit 40A and the shutoff unit 40B.

[0112] In the air conditioning and hot water supply system 2, there may be a case where the first heat medium RF1 leaks from either the indoor unit 30A or the indoor unit 30B, and the first heat medium RF1 does not leak from the other. The control unit in the control unit 150 controls either the shutoff unit 40A or the shutoff unit 40B connected to the leaking indoor unit 30A or the indoor unit 30B to be shut off. Then, the control unit in the control unit 150 controls either the shutoff unit 40A or the shutoff unit 40B connected to the other of the leaking indoor unit 30A or the indoor unit 30B not to be shut off.

[0113] The control section in the control unit 150 shuts off only the shutoff unit connected to the leaking indoor unit, allowing indoor units that are not leaking to continue operating.

[0114] Although the air conditioning and hot water supply system 2 has been described as having two indoor units as an example, the air conditioning and hot water supply system 2 of the second embodiment may also have three or more indoor units and the same number of shut-off units as the indoor units.

[0115] According to the air conditioning and hot water supply system of the second embodiment, if a refrigerant leaks in an indoor unit, the hot water supply function can be continued. Also, according to the air conditioning and hot water supply system of the second embodiment, if a refrigerant leaks in an indoor unit, the operation of indoor units that are not leaking refrigerant can be continued.

[0116] When multiple indoor units are provided, all of the multiple indoor units may be in heating operation or cooling operation, or some of the multiple indoor units may be in heating operation and some in cooling operation.

[0117] Although the embodiment has been described above, it will be understood that various changes in form and details are possible without departing from the spirit and scope of the claims. Various modifications and improvements, such as combinations and substitutions with part or all of other embodiments, are possible. [Explanation of symbols]

[0118] 1, 2 Air conditioning and hot water system 10 Outdoor unit 11 Compressor 12 Accumulator 13a, 13b heat exchanger 14a, 14b Expansion valve 15a, 15b, 15c four-way switching valve 16 Fans 20 Hot water unit 20s Cascade Heat Transfer Medium Circuit 21 Compressor 22 Accumulator 23, 24 Heat exchanger 25, 26 Expansion valve 27 Pump 28 Four-way switching valve 29a, 29b Check valve 30, 30A, 30B Indoor unit 31 Heat exchanger 32 Expansion valve 33 Detector 34 Fans 40, 40A, 40B Breaking Unit 41, 42 Shut-off valve 50, 150 Control Unit 51 Control section 60, 60a, 60b Cooling / heating switching unit 61 Heat exchanger 62, 63, 64 Control valve RF1 1st heat carrier RF2 2nd heat medium

Claims

1. an outdoor unit including a compressor that compresses a first heat medium and supplies the first heat medium; a hot water supply unit that generates hot water using the first heat medium supplied from the outdoor unit; an indoor unit that performs air conditioning using the first heat medium supplied from the outdoor unit; a blocking unit that blocks the first heat medium flowing into the indoor unit; a control unit that, when the first heat medium leaks from the indoor unit, controls the blocking unit to block the first heat medium flowing into the indoor unit, continues operation of the compressor, and continues supply of the first heat medium from the outdoor unit to the hot water supply unit; Equipped with Air conditioning and hot water system.

2. The hot water supply unit includes a cascade heat medium circuit that generates hot water by a second heat medium that has exchanged heat with the first heat medium. The air conditioning and hot water supply system according to claim 1 .

3. The cascade heat medium circuit continues circulation of the second heat medium when the first heat medium leaks in the indoor unit. The air conditioning and hot water supply system according to claim 2 .

4. The first heat medium is R32, The second heat medium is 1234yf; The air conditioning and hot water supply system according to claim 2 or 3.

5. The indoor unit includes an expansion valve. The expansion valve functions as a shutoff valve in the shutoff unit. The air conditioning and hot water supply system according to any one of claims 1 to 3.

6. After the shutoff unit is shut off, the amount m of the first heat medium discharged from the indoor unit satisfies Equation 1. The air conditioning and hot water supply system according to any one of claims 1 to 3. [0010] where max(a, b) is a function that returns the larger of a and b, min(a, b) is a function that returns the smaller of a and b, and LFL is the lower flammability limit of the first heat medium (unit: kilogram per cubic meter (kg / m ３ )), A is the minimum room area (unit: square meters (m ２ )), h ０ is the floor height (unit: meters (m)), SF is a constant (0.5), and the floor height h ０ is calculated based on Equation 4. [0025] However, h ｉｎｓｔ is the height of the bottom surface of the product from the floor, h ｒｅｌ is the height from the bottom of the product of the opening that has a cumulative open area of ​​5 square centimeters from the bottom (excluding holes with dimensions of 0.1 millimeters or less).

7. A plurality of the indoor units are provided, and a plurality of the shutoff units are provided for each of the indoor units, The control unit controls the blocking unit in the indoor unit in which the first heat medium has leaked to block the first heat medium, and to continue supplying the first heat medium to the indoor units other than the indoor unit in which the first heat medium has leaked. The air conditioning and hot water supply system according to any one of claims 1 to 3.

8. The first heat medium is a slightly flammable refrigerant or a flammable refrigerant. The air conditioning and hot water supply system according to any one of claims 1 to 3.

9. The first heat medium is R32. The air conditioning and hot water supply system according to any one of claims 1 to 3.

10. When the capacity of the indoor unit with the shutoff unit closed is equal to or greater than a predetermined capacity relative to the capacity of the outdoor unit, the operation of the compressor is stopped. The air conditioning and hot water supply system according to any one of claims 1 to 3.

11. an outdoor unit including a compressor that compresses a first heat medium and supplies the first heat medium; a hot water supply unit that generates hot water using the first heat medium supplied from the outdoor unit; an indoor unit that performs air conditioning using the first heat medium supplied from the outdoor unit; a blocking unit that blocks the first heat medium flowing into the indoor unit; A control method for an air conditioning and hot water supply system comprising: When the first heat medium leaks from the indoor unit, the blocking unit blocks the first heat medium flowing into the indoor unit, and the compressor continues to operate, thereby continuing the supply of the first heat medium from the outdoor unit to the hot water supply unit. A method for controlling an air conditioning and hot water system.

12. an outdoor unit including a compressor that compresses a first heat medium and supplies the first heat medium; a hot water supply unit that generates hot water using the first heat medium supplied from the outdoor unit; an indoor unit that performs air conditioning using the first heat medium supplied from the outdoor unit; a blocking unit that blocks the first heat medium flowing into the indoor unit; A control device for use in an air conditioning and hot water supply system comprising: When the first heat medium leaks from the indoor unit, the first heat medium flowing to the indoor unit is blocked by the blocking unit, and the operation of the compressor is continued, and the supply of the first heat medium from the outdoor unit to the hot water supply unit is continued. Control device.

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