Air conditioner

Abstract

To provide an air conditioner preventing refrigerant gas from leaking into a room.SOLUTION: An air conditioner, for which refrigerant containing ethylene-system fluoro olefin is used, includes: an outdoor unit having an outdoor heat exchanger, a compressor and an expansion valve; an indoor unit having a housing provided with an indoor air suction port and a blowout port, an indoor fan disposed in the housing and forming airflow to the blowout port from the suction port, and an indoor heat exchanger located at an airflow route; a refrigerant piping which connects the outdoor heat exchanger, the compressor, the expansion valve and the indoor heat exchanger and through which the refrigerant is circulated; an exhaust fan exhausting the air inside the indoor unit to the outside and a control part controlling the outdoor unit, the indoor unit and the exhaust fan. The exhaust fan is constituted so as to exhaust the air to the outside from the exhaust air suction port provided to the inside of the housing of the indoor unit and also to the outside of the airflow route.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to an air conditioner. [Background technology]

[0002] From the viewpoint of preventing global warming, the use of refrigerants with low global warming potential (GWP) in air conditioners has been considered. As refrigerants with low GWP, for example, 1,1,2-trifluoroethylene (HFO1123) or 1,2-difluoroethylene (HFO1132) has been considered. These refrigerants may cause disproportionation reactions.

[0003] Suppression of disproportionation reactions has been studied in air conditioners that use refrigerants such as HFO1123 or HFO1132. For example, the air conditioner described in Patent Document 1 includes an outdoor unit, an indoor unit, and an outdoor unit control means, and the outdoor unit control means performs control to close the liquid side shutoff valve and the gas side shutoff valve when a refrigerant leakage sensor detects a refrigerant leakage. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-169072 A Summary of the Invention [Problem to be solved by the invention]

[0005] The air conditioner described in Patent Document 1 still has room for improvement in terms of preventing leakage of refrigerant gas into the room.

[0006] The present disclosure provides an air conditioner that can suppress leakage of refrigerant gas into a room. [Means for solving the problem]

[0007] An air conditioner according to one aspect of the present disclosure includes: An air conditioner that uses a refrigerant containing an ethylene-based fluoroolefin, an outdoor unit having an outdoor heat exchanger, a compressor, and an expansion valve; an indoor unit including a housing provided with an indoor air intake port and an exhaust port, an indoor fan disposed within the housing and forming an airflow from the intake port to the exhaust port, and an indoor heat exchanger located on a path of the airflow; a refrigerant pipe that connects the outdoor heat exchanger, the compressor, the expansion valve, and the indoor heat exchanger and through which the refrigerant circulates; An exhaust fan that exhausts air from inside the indoor unit to the outside; A control unit that controls the outdoor unit, the indoor unit, and the exhaust fan; Equipped with The exhaust fan is configured to exhaust air to the outside of the room from an exhaust inlet provided inside the housing of the indoor unit and outside the path of the airflow. Effect of the Invention

[0008] According to the present disclosure, it is possible to provide an air conditioner that can suppress leakage of refrigerant gas into the room. [Brief description of the drawings]

[0009] [Figure 1] Schematic diagram of an air conditioner according to a first embodiment of the present disclosure. [Diagram 2] An enlarged schematic diagram of the indoor unit of the air conditioner in Figure 1. [Diagram 3] Schematic diagram of the indoor unit in Figure 2 seen from a different angle [Figure 4] FIG. 2 is a block diagram showing the configuration of the air conditioner of FIG. 1. [Diagram 5] A timing chart showing an example of operation control of the air conditioner of FIG. [Figure 6] 1 is a timing chart showing an example of operation control of an air conditioner according to a modification of the first embodiment. [Figure 7] FIG. 13 is a schematic diagram showing an indoor unit of an air conditioner according to a second embodiment. [Figure 8] FIG. 8 is a schematic diagram showing the indoor unit of FIG. 7 in a closed state; [Figure 9] FIG. 13 is a schematic diagram showing an indoor unit of an air conditioner according to a third embodiment. [Figure 10] Schematic diagram of the indoor unit in Figure 9 seen from a different angle [Figure 11] A timing chart showing an example of operation control of an air conditioner according to a third embodiment. [Figure 12] FIG. 13 is a schematic diagram of an air conditioner according to a fourth embodiment of the present disclosure. [Figure 13] FIG. 13 is a schematic diagram showing an indoor unit of the air conditioner of FIG. [Figure 14] FIG. 13 is a schematic diagram showing an indoor unit of an air conditioner according to a fifth embodiment. [Figure 15] A timing chart showing an example of operation control of an air conditioner according to a fifth embodiment. [Figure 16] A flowchart showing an example of operation control of an air conditioner according to a first modification of the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] (Background to this disclosure) Refrigerants such as R410A are widely used in air conditioners. However, the global warming potential (GWP) of R410A is high at 2090. Therefore, from the perspective of preventing global warming, research and development of refrigerants with lower GWP is being conducted. Refrigerants with lower GWP than R410A are known, such as 1,1,2-trifluoroethylene (HFO1123) and 1,2-difluoroethylene (HFO1132).

[0011] HFO1123 or HFO1132 has a smaller GWP than R410A, but is less stable than R410A. For example, the generation of radicals can cause disproportionation reactions of HFO1123 or HFO1132, which can change HFO1123 or HFO1132 into other compounds.

[0012] In an air conditioner equipped with an indoor unit and an outdoor unit, if a refrigerant leaks inside the indoor unit, the leaked refrigerant may cause a disproportionation reaction. In this case, in order to improve the safety and reliability of the air conditioner, it is important to suppress the leakage of gas generated by the disproportionation reaction into the room.

[0013] The present inventors have studied the structure of an air conditioner for suppressing leakage of refrigerant gas into the room, and have arrived at the following invention.

[0014] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings in some cases. However, the following embodiments are examples for explaining the present disclosure, and are not intended to limit the present disclosure to the following contents (e.g., the shape, dimensions, arrangement, etc. of each component). Positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings unless otherwise specified. Each figure described in the following embodiments is a schematic diagram, and the size and thickness ratios of each component in each figure do not necessarily reflect the actual dimensional ratios. Furthermore, the dimensional ratios of each element are not limited to the ratios shown in the drawings.

[0015] In the following description, when it is necessary to distinguish between multiple components, prefixes such as "first" and "second" are added to the names of the components. However, when the components can be distinguished from one another by the symbols added to them, the prefixes such as "first" and "second" may be omitted in consideration of readability of the text.

[0016] (Embodiment 1) [Overall configuration] Fig. 1 is a schematic diagram of an air conditioner 10 according to a first embodiment of the present disclosure. Fig. 2 is an enlarged schematic diagram of an indoor unit 20 of the air conditioner 10 in Fig. 1. Fig. 3 is a schematic diagram of the indoor unit 20 in Fig. 2 viewed from a different angle.

[0017] As shown in Figures 1 to 3, the air conditioner 10 of this embodiment comprises an indoor unit 20 arranged in a room Rin to be air-conditioned, an outdoor unit 30 arranged in the outdoor Rout, refrigerant piping 50, an exhaust fan 60, and a control unit 70.

[0018] The outdoor unit 30 has an outdoor heat exchanger 32, a compressor 36, and an expansion valve 38. The indoor unit 20 has a housing 28, an indoor fan 24, and an indoor heat exchanger 22. The refrigerant piping 50 connects the outdoor heat exchanger 32, the compressor 36, the expansion valve 38, and the indoor heat exchanger 22. A refrigerant circulates through the refrigerant piping 50. The exhaust fan 60 exhausts air inside the indoor unit 20 to the outdoor Rout. In this embodiment, as shown in FIG. 3, the exhaust fan 60 is disposed inside the indoor unit 20. The control unit 70 controls the outdoor unit 30, the indoor unit 20, and the exhaust fan 60.

[0019] As shown in Fig. 2, a housing 28 of the indoor unit 20 is provided with an inlet 26 and an outlet 27 for the indoor air A1. The indoor fan 24 is disposed in the housing 28 and forms an airflow F1 from the inlet 26 to the outlet 27. In other words, the indoor fan 24 draws the indoor air A1 from the inlet 26 into the indoor unit 20, and blows the indoor air A1 after heat exchange with the indoor heat exchanger 22 out from the outlet 27 into the room Rin. The indoor heat exchanger 22 is disposed in the path of the airflow F1 formed by the indoor fan 24 and exchanges heat with the indoor air A1.

[0020] The outdoor unit 30 is provided with an outdoor heat exchanger 32 that exchanges heat with the outdoor air A2, and a fan 34 that draws the outdoor air A2 into the outdoor unit 30 and blows the outdoor air A2 after heat exchange with the outdoor heat exchanger 32 out to the outdoor Rout. The outdoor unit 30 is also provided with a compressor 36, an expansion valve 38, and a four-way valve 40 that execute a refrigeration cycle with the indoor heat exchanger 22 and the outdoor heat exchanger 32.

[0021] The indoor heat exchanger 22, the outdoor heat exchanger 32, the compressor 36, the expansion valve 38, and the four-way valve 40 are connected by a refrigerant piping 50 through which a refrigerant circulates. In this embodiment, as shown in Fig. 3, the refrigerant piping 50 has a plurality of heat transfer tubes 52 arranged in the housing 28 of the indoor unit, a plurality of first bend tubes 54 connecting one ends 52a of the plurality of heat transfer tubes together, and a plurality of second bend tubes 56 connecting the other ends 52b of the plurality of heat transfer tubes 52 together.

[0022] When the air conditioner 10 performs cooling operation and dehumidification operation (weak cooling operation), the refrigeration cycle is performed by the refrigerant flowing in order from the compressor 36 through the four-way valve 40, the outdoor heat exchanger 32, the expansion valve 38, the indoor heat exchanger 22, and returning to the compressor 36. When the air conditioner performs heating operation, the refrigeration cycle is performed by the refrigerant flowing in order from the compressor 36 through the four-way valve 40, the indoor heat exchanger 22, the expansion valve 38, the outdoor heat exchanger 32, and returning to the compressor 36.

[0023] In this embodiment, the refrigerant includes an ethylene-based fluoroolefin. The ethylene-based fluoroolefin may be an ethylene-based fluoroolefin that undergoes a disproportionation reaction. Examples of the ethylene-based fluoroolefin that undergoes a disproportionation reaction include 1,1,2-trifluoroethylene (HFO1123), trans-1,2-difluoroethylene (HFO1132(E)), cis-1,2-difluoroethylene (HFO-1132(Z)), 1,1-difluoroethylene (HFO-1132a), tetrafluoroethylene (CF2=CF2, FO1114), and monofluoroethylene (HFO-1141).

[0024] The refrigerant may contain multiple types of refrigerant components. For example, the refrigerant may contain an ethylene-based fluoroolefin as a main refrigerant component and a compound other than an ethylene-based fluoroolefin as a secondary refrigerant component. Examples of secondary refrigerant components include hydrofluorocarbons (HFCs), hydrofluoroolefins (HFOs), saturated hydrocarbons, carbon dioxide, and the like. Examples of hydrofluorocarbons (HFCs) include difluoromethane, difluoroethane, trifluoroethane, tetrafluoroethane, pentafluoroethane, pentafluorobutane, heptafluorocyclopentane, and the like. Examples of hydrofluoroolefins (HFOs) include monofluoropropene, trifluoropropene, tetrafluoropropene, pentafluoropropene, hexafluorobutene, and the like. Examples of saturated hydrocarbons include ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2-dimethylpropane), methylcyclobutane, and the like.

[0025] The refrigerant may further contain a disproportionation inhibitor that suppresses the disproportionation reaction of ethylene-based fluoroolefins. Examples of disproportionation inhibitors include saturated hydrocarbons or haloalkanes. Examples of saturated hydrocarbons include ethane, n-propane, cyclopropane, n-butane, cyclobutane, isobutane (2-methylpropane), methylcyclopropane, n-pentane, isopentane (2-methylbutane), neopentane (2,2-dimethylpropane), methylcyclobutane, etc. In the above examples, n-propane is preferred. Examples of haloalkanes include haloalkanes with 1 or 2 carbon atoms. Examples of haloalkanes having one carbon atom (i.e., halomethanes) include (mono)iodomethane (CH3I), diiodomethane (CH2I2), dibromomethane (CH2Br2), bromomethane (CH3Br), dichloromethane (CH2Cl2), chloroiodomethane (CH2ClI), dibromochloromethane (CHBr2Cl), tetraiodomethane (CI4), carbon tetrabromide (CBr4), bromotrichloromethane (CBrCl3), dibromodichloromethane (CBr2Cl2), tribromofluoromethane (CBr3F), fluorodiiodomethane (CHFI2), difluorodiiodomethane (CF2I2), dibromodifluoromethane (CBr2F2), trifluoroiodomethane (CF3I), difluoroiodomethane (CHF2I), and the like. Examples of haloalkanes having 2 carbon atoms (i.e., haloethanes) include 1,1,1-trifluoro-2-iodoethane (CF3CH2I), monoiodoethane (CH3CH2I), monobromoethane (CH3CH2Br), and 1,1,1-triiodoethane (CH3CI3). The refrigerant may contain one or more types of haloalkanes having 1 or 2 carbon atoms. In other words, the refrigerant may contain only one type of haloalkane having 1 or 2 carbon atoms, or two or more types of haloalkanes may be used in appropriate combination.

[0026] As shown in FIG. 3, the exhaust fan 60 is configured to exhaust air to the outdoor Rout from exhaust suction ports 62, 63 provided inside the housing 28 of the indoor unit 20 and outside the path of the airflow F1 of the indoor air A1. As described above, in this embodiment, the airflow F1 is formed from the suction port 26 to the outlet 27 of the indoor unit 20 by the rotation of the indoor fan 24. The indoor heat exchanger 22 is disposed in the path of the airflow F1. Meanwhile, the exhaust suction ports 62, 63 are provided inside the housing 29 of the indoor unit 20 and outside the path of the airflow F1. As shown in FIG. 3, the exhaust suction ports 62, 63 are provided on both sides of the indoor heat exchanger 22 inside the housing 28 so that air can be sucked from spaces formed at both ends of the indoor heat exchanger 22. In addition, the air inside the indoor unit 20 sucked by the exhaust fan 60 is exhausted to the outdoor Rout by the exhaust duct 64. In this embodiment, the exhaust air inlet includes a first air inlet 62 and a second air inlet 63. More specifically, the exhaust air inlet includes a first air inlet 62 arranged in a first space S1 in which a plurality of first bend pipes 54 are arranged, and a second air inlet 63 arranged in a second space S2 in which a plurality of second bend pipes 56 are arranged. In this embodiment, the first space S1 is outside the air flow F1 inside the housing 28 and refers to a space near one end of the housing 28. Also, in this embodiment, the second space S2 is outside the air flow F1 inside the housing 28 and refers to a space near the other end of the housing 28. Therefore, air near the first space S1 flows from the first air inlet 62 in the direction of the arrow R1 and is exhausted to the outside Rout by the exhaust fan 60. Moreover, air in the vicinity of the second space S2 flows from the second suction port 63 in the direction of the arrow R2 and is exhausted by the exhaust fan 60 to the outside Rout.

[0027] The first bend pipe 54 and the second bend pipe 56 are components that connect the multiple heat transfer pipes 52. The bend pipes 54, 56 have, for example, a U-shaped curved shape. The refrigerant circulating inside the heat transfer pipes may leak from the connection between the bend pipes 54, 56 and the heat transfer pipe 52. Therefore, by providing exhaust suction ports 62, 63 in the first space S1 and the second space S2, it is possible to make it easier for the exhaust fan 60 to suck in air near the first bend pipe 54 and the air near the second bend pipe 56 and discharge the air to the outdoor Rout.

[0028] When a disproportionation reaction occurs and the refrigerant leaks inside the indoor unit 20, the leaked refrigerant gas tends to accumulate in the first space S1 and the second space S2. Therefore, by providing the exhaust suction ports 62, 63 in the first space S1 and the second space S2, the refrigerant gas can be efficiently discharged when a refrigerant leak occurs inside the indoor unit 20. Therefore, even if a refrigerant leaks inside the indoor unit 20, the refrigerant gas can be prevented from being discharged into the room Rin, and the safety of the air conditioner 10 can be improved.

[0029] Fig. 4 is a block diagram showing the configuration of the air conditioner 10 of Fig. 1. The control unit 70 operates the exhaust fan 60 to exhaust air in the first space S1 and the second space S2 of the indoor unit 20 to the outdoor Rout. The control unit 70 may operate the exhaust fan 60 while the compressor 36 is in operation, for example. In this embodiment, as shown in Figs. 3 and 4, the control unit 70 is disposed inside the indoor unit 20. The control unit 70 may be disposed in the outdoor unit 30, or may be disposed separately from the indoor unit 20 and the outdoor unit 30.

[0030] FIG. 5 is a timing chart showing an example of operation control of the air conditioner 10 of FIG.

[0031] As shown in FIG. 5, the control unit 70 operates the exhaust fan 60 while the compressor 36 is operating, for example. That is, the control unit 70 may operate the exhaust fan 60 in conjunction with the operation of the compressor 36. During the operation of the compressor 36, the refrigerant circulates through the refrigerant piping 50, and therefore the refrigerant may leak from the first bend pipe 54 and the second bend pipe 56. For this reason, by operating the exhaust fan 60 while the compressor 36 is operating, air can be continuously discharged from the first space S1 and the second space S2 of the indoor unit 20 to the outdoor Rout while the compressor 36 is operating. For this reason, leakage of the refrigerant gas into the indoor Rin can be suppressed.

[0032] [effect] According to the above-described embodiment, the following effects can be obtained.

[0033] The air conditioner 10 uses a refrigerant containing an ethylene-based fluoroolefin, and includes an outdoor unit 30, an indoor unit 20, a refrigerant pipe 50, an exhaust fan 60, and a control unit 70. The outdoor unit 30 has an outdoor heat exchanger 32, a compressor 36, and an expansion valve 38. The indoor unit 20 has a housing 28, an indoor fan 24, and an indoor heat exchanger 22. The housing 28 is provided with an inlet 26 and an outlet 27 for indoor air A1. The indoor fan 24 is disposed in the housing 28 and forms an airflow F1 from the inlet 26 to the outlet 27. The indoor heat exchanger 22 is located on the path of the airflow F1. The refrigerant pipe 50 connects the outdoor heat exchanger 32, the compressor 36, the expansion valve 38, and the indoor heat exchanger 22, and the refrigerant circulates. The exhaust fan 60 exhausts the air inside the indoor unit 20 to the outdoor Rout. The control unit 70 controls the outdoor unit 30, the indoor unit 20, and the exhaust fan 60. The exhaust fan 60 is configured to exhaust air to the outdoor Rout from exhaust intakes 62, 63 provided inside the housing 28 of the indoor unit 20 and outside the path of the airflow F1.

[0034] With this configuration, it is possible to provide an air conditioner that can suppress leakage of refrigerant gas into the room Rin. The exhaust fan 60 can exhaust air inside the indoor unit 20 to the outdoor Rout. Therefore, the exhaust fan 60 can exhaust the refrigerant gas to the outdoor Rout, suppressing leakage of the refrigerant gas into the room Rin, and improving the safety of the air conditioner 10.

[0035] The control unit 70 may operate the exhaust fan 60 while the compressor 36 is in operation.

[0036] With this configuration, the air inside the indoor unit 20 can be continuously discharged to the outside Rout while the compressor 36 is operating, which may cause refrigerant gas leakage, thereby further suppressing leakage of refrigerant gas into the room Rin.

[0037] The refrigerant piping 50 may have a plurality of heat transfer tubes 52 arranged in the housing 28 of the indoor unit 20, a plurality of first bend tubes 54 connecting one ends 52a of the plurality of heat transfer tubes 52, and a plurality of second bend tubes 56 connecting the other ends 54b of the plurality of heat transfer tubes 52. One end of the plurality of heat transfer tubes 52 may be bent into a U-shape. The exhaust suction ports 62, 63 may be arranged in the first space S1 in which the plurality of first bend tubes 54 are arranged and in the second space S2 in which the plurality of bend tubes 56 are arranged. The exhaust fan 60 is arranged in the indoor unit 20 and configured to exhaust air inside the housing 28 from the exhaust suction ports 62, 63.

[0038] With this configuration, the air in the first space S1 and the second space S2, from which the refrigerant may leak, can be efficiently discharged to the outside Rout.

[0039] The exhaust suction ports 62, 63 may include a first suction port 62 disposed in the first space S1 and a second suction port 63 disposed in the second space S2.

[0040] With this configuration, the air in each of the first space S1 and the second space S2 can be efficiently discharged to the outside Rout.

[0041] In the above embodiment, the exhaust suction ports 62, 63 are provided in the first space S1 and the second space S2, respectively, but the present invention is not limited to this. The exhaust suction port may be provided in at least one of the first space S1 and the second space S2.

[0042] In the above embodiment, the control unit 70 stops the operation of the compressor 36 and the exhaust fan 60, but the present invention is not limited to this. It is sufficient that the exhaust fan 60 is operating at least while the compressor 36 is operating, and the control unit 70 may continue to operate the exhaust fan 60 after the compressor 36 is stopped.

[0043] Furthermore, in the above-described embodiment, an example has been described in which the control unit 70 operates the exhaust fan 60 while the compressor 36 is operating, but the present invention is not limited to this. Fig. 6 is a timing chart showing an example of operation control of the air conditioner 10 according to a modified example of the first embodiment. As shown in Fig. 6, the control unit 70 may, for example, operate the exhaust fan at a predetermined time after the operation of the compressor 36 is stopped.

[0044] In Fig. 6, the control unit 70 switches the compressor 36 from ON to OFF at time t1. After stopping the compressor 36 at time t1, the control unit 70 continues to operate the exhaust fan for a predetermined time and switches it from ON to OFF at time t2. In this way, by stopping the exhaust fan 60 with a time lag from when the compressor 36 stops operating, it is possible to continue discharging air from the indoor unit 20 to the outdoor Rout for a while after the compressor 36 stops. Therefore, even if refrigerant gas that has leaked into the indoor unit 20 remains, leakage into the indoor Rin can be suppressed.

[0045] (Embodiment 2) A second embodiment will be described with reference to Figures 7 and 8. In the second embodiment, the same or equivalent configurations as those in the first embodiment will be denoted by the same reference numerals. In the second embodiment, descriptions that overlap with those in the first embodiment will be omitted.

[0046] Fig. 7 is a schematic diagram showing indoor unit 20A of an air conditioner according to embodiment 2. Fig. 8 is a schematic diagram showing a state in which switching units 66, 67 of indoor unit 20A in Fig. 7 are closed. As shown in Fig. 7, embodiment 2 differs from embodiment 1 in that indoor unit 20A further includes a first switching unit 66 that switches between opening and closing of first suction port 62, and a second switching unit 67 that switches between opening and closing of second suction port 63. Other configurations are the same as those of air conditioner 10 in embodiment 1, and therefore description thereof will be omitted.

[0047] The first switching unit 66 and the second switching unit 67 are elements that can switch between opening and closing the first suction port 62 and the second suction port 63, and can be configured, for example, by a member such as a lid and a drive unit that can move the member such as the lid between an open position and a closed position. In this embodiment, the first switching unit 66 and the second switching unit 67 can cover the first suction port 62 and the second suction port 63 by sliding them toward the first suction port 62 and the second suction port 63 as shown in FIG. 8. By arranging the first switching unit 66 and the second switching unit 67 in the indoor unit 20A, it is possible to exhaust air from either the first space S1 or the second space S2 to the outdoor Rout, or to exhaust air from both the first space S1 and the second space S2 to the outdoor Rout.

[0048] [effect] According to the above-described embodiment, the following effects can be obtained.

[0049] The indoor unit 20A may further include a first switching section 66 that switches between opening and closing the first suction port 62, and a second switching section 67 that switches between opening and closing the second suction port.

[0050] With this configuration, the air stagnating in the first space S1 or the second space S2 can be selectively discharged to the outside Rout.

[0051] In the above embodiment, an example has been described in which the indoor unit 20A has two switching units 66, 67, the first switching unit 66 and the second switching unit 67, but the present invention is not limited to this. The indoor unit 20 may have at least one of the first switching unit 66 and the second switching unit 67.

[0052] (Embodiment 3) A third embodiment will be described with reference to Fig. 9 and Fig. 10. In the third embodiment, the same or equivalent configurations as those in the second embodiment will be denoted by the same reference numerals. In the third embodiment, descriptions that overlap with those in the second embodiment will be omitted.

[0053] Fig. 9 is a schematic diagram showing an indoor unit 20B of an air conditioner according to embodiment 3. Fig. 10 is a schematic diagram showing the indoor unit 20B of Fig. 9 viewed from another direction. As shown in Fig. 9, embodiment 3 differs from embodiment 2 in that an air filter 80 and a dust collection section 82 are arranged in the indoor unit. Other configurations of the air conditioner are similar to those of embodiment 2, and therefore description thereof will be omitted.

[0054] As shown in Figs. 9 and 10, the indoor unit 20B has an air filter 80 through which indoor air A1 flows from the room Rin toward the indoor heat exchanger 22. Note that the air filter 80 and a brush 82a, which will be described later, are omitted in Fig. 10. The indoor unit 20B also has a dust collection section 82 that collects and contains dust adhering to the air filter 80. Furthermore, in this embodiment, the exhaust outlet includes a third suction port 84 provided in the dust collection section 82.

[0055] 9, dust collection section 82 includes, for example, brush 82a for removing dust from air filter 80, and storage section 82b for storing dust removed by brush 82a from air filter 80. The configuration of dust collection section 82 is not limited thereto, and may be any configuration capable of removing dust from air filter 80.

[0056] As shown in FIG. 10, in this embodiment, a third suction port 84 is provided at one end 83a of the storage section 82b. A second suction port 63a is provided at the other end 83b of the storage section 82b. With this configuration, the storage section 82b has two functions: an intake duct for drawing air from the second space S2, and a storage section for storing dust. By operating the first switching section 66 and the second switching section 67 to close the first suction port 62 and the second suction port 63, the exhaust fan 60 can be operated to discharge the dust accumulated in the storage section 82b.

[0057] For example, when the indoor fan 24 is stopped, the control unit 70 operates the dust collection unit 82 to remove dust from the air filter 80. When the dust removed from the air filter 80 by the brush 82a is stored in the storage unit 82b, the control unit 70 operates the exhaust fan to suck in the dust from the third suction port 84 shown in Fig. 10 and discharges the dust through the exhaust duct 64 to the outside Rout.

[0058] Fig. 11 is a timing chart showing an example of operation control of the air conditioner according to embodiment 3. Control of the compressor 36, the indoor fan 24, the exhaust fan 60, and the dust collection unit 82 according to embodiment 3 will be described in more detail with reference to Fig. 11.

[0059] When the air conditioner is in cooling operation or heating operation, that is, until time t3 in Fig. 11, the control unit 70 operates the compressor 36 and the indoor fan 24. Furthermore, until time t3 in Fig. 11, the control unit 70 also operates the exhaust fan 60. At this time, the first suction port 62 and the second suction port 63 are open, and the exhaust fan 60 exhausts air near the first space S1 and the second space S2 to the outdoor area Rout.

[0060] When the cooling operation or heating operation ends at time t3, the control unit 70 stops the compressor 36 and the indoor fan 24. Also, at time t3, the control unit 70 operates the dust collection unit 82 to clean the air filter 80.

[0061] At time t4, when the control unit 70 stops the dust collection unit 82 and finishes cleaning the air filter 80, the control unit 70 controls the first switching unit 66 and the second switching unit 67 to close the first suction port 62 and the second suction port 63a. At this time, the exhaust fan 60 remains operating, and by closing the first suction port 62 and the second suction port 63a, the dust accumulated in the storage unit 82b can be sucked out and discharged to the outside Rout.

[0062] The control unit 70 stops the exhaust fan 60 at time t5, and stops the operation of the air conditioner.

[0063] [effect] According to the above-described embodiment, the following effects can be obtained.

[0064] The indoor unit 20B further has an air filter 80 through which the indoor air A1 passing from the room Rin toward the indoor heat exchanger 22 passes, and a dust collection section 82 that collects and accommodates dust adhering to the air filter 80. The exhaust suction port further includes a third suction port 84 provided in the dust collection section 82. The dust collection section 82 is configured to collect dust on the air filter 80 when the indoor fan 24 is not operating. The control section 70 operates the exhaust fan 60 when the indoor fan 24 is not operating to suck in dust from the third suction port 84 and discharge it to the outdoor Rout.

[0065] With this configuration, the exhaust fan 60 can have two functions: a function to exhaust air inside the indoor unit 20B to the outdoor Rout, and a function to exhaust dust removed from the air filter 80 to the outdoor Rout. By giving the exhaust fan 60 two functions, the manufacturing costs of the air conditioner can be reduced.

[0066] In the above-described embodiment, an example having the first switching unit 66 and the second switching unit 67 has been described, but the present invention is not limited to this. In the indoor unit 20B having the air filter 80, the dust collection unit 82, and the third suction port 84, the switching units 66 and 67 do not necessarily have to be provided.

[0067] (Embodiment 4) A fourth embodiment will be described with reference to Fig. 12 and Fig. 13. In the fourth embodiment, the same or equivalent configurations as those in the first embodiment will be denoted by the same reference numerals. In the fourth embodiment, descriptions that overlap with those in the first embodiment will be omitted.

[0068] Fig. 12 is a schematic diagram of an air conditioner 110 according to a fourth embodiment of the present disclosure. Fig. 13 is a schematic diagram showing an indoor unit 120 of the air conditioner 110 of Fig. 12. As shown in Figs. 12 and 13, the fourth embodiment differs from the first embodiment in that the outdoor unit 130 includes a ventilation device 150 that exhausts indoor air A1 from the room Rin to the room Rout, and an exhaust fan 160 is disposed in the ventilation device 150.

[0069] As shown in Fig. 12, the ventilation device 150 is disposed in the outdoor unit 130 and connected to the indoor unit 120 via a ventilation hose 156. An exhaust fan 160 is disposed in the ventilation device 150. By operating the exhaust fan 160, indoor air A1 is sucked in and exhausted to the outdoor Rout via the ventilation hose 156. That is, the ventilation device 150 can perform exhaust ventilation operation in the air conditioner 110.

[0070] As shown in FIG. 13, the indoor unit 120 is provided with a first suction port 162 and a second suction port 163, and when the exhaust fan 60 of the ventilation device 150 is operated, air near the first space S1 and the second space S2 is exhausted to the outside Rout via the ventilation hose 156.

[0071] [effect] According to the above-described embodiment, the following effects can be obtained.

[0072] The outdoor unit 130 includes a ventilation device 150 that exhausts indoor air A1 from the room Rin to the outdoor Rout. The exhaust fan 160 is disposed in the ventilation device 150.

[0073] With this configuration, it is not necessary to provide the exhaust fan 160 inside the indoor unit 120, and therefore it is possible to reduce the size of the indoor unit 120. Furthermore, it is possible to provide the air conditioner 110 with an exhaust ventilation function.

[0074] (Embodiment 5) A fifth embodiment will be described with reference to Fig. 14. In the fifth embodiment, the same or equivalent configurations as those in the first embodiment will be denoted by the same reference numerals. In the fifth embodiment, descriptions that overlap with those in the first embodiment will be omitted.

[0075] 14 is a schematic diagram showing an indoor unit 20C of an air conditioner according to embodiment 5. Embodiment 5 differs from embodiment 1 in that the indoor unit 20C further includes sensors 90, 92 for detecting refrigerant gas inside the housing 28.

[0076] 14, in this embodiment, two sensors, a sensor 90 and a sensor 92, are arranged. The sensor 90 can detect refrigerant gas mainly in the first space S1, and the sensor 92 can detect refrigerant gas mainly in the second space S2. By detecting the refrigerant gas with the sensors 90 and 92, leakage of the refrigerant from the refrigerant pipe 50 can be detected.

[0077] When the sensors 90, 92 detect refrigerant gas while the compressor 36 is operating, the control unit 70 stops the operation of the compressor 36 and operates the exhaust fan 60.

[0078] FIG. 15 is a timing chart showing an example of operation control of the air conditioner of the fifth embodiment. As shown in FIG. 15, when the refrigerant gas is detected by the sensors 90 and 92, and the detection value exceeds a predetermined threshold value V1, for example, the control unit 70 stops the operation of the compressor 36. When the indoor fan 24 is in operation, the control unit 70 may stop the operation of the indoor fan 24 together with the compressor 36. In the example of FIG. 15, the detection values ​​of the sensors 90 and 92 exceed the threshold value V1 at time t6. At this time, the control unit 70 operates the exhaust fan 60. For example, when the detection value of either one of the sensors 90 and 92 exceeds the predetermined threshold value V1, the control unit 70 may stop the compressor 36 and operate the exhaust fan 60. Alternatively, when the detection values ​​of both the sensors 90 and 92 exceed the predetermined threshold value V1, the control unit 70 may stop the compressor 36 and operate the exhaust fan 60.

[0079] [effect] According to the above-described embodiment, the following effects can be obtained.

[0080] The indoor unit 20C further has sensors 90, 92 that detect refrigerant gas inside the housing 28. When the sensors 90, 92 detect refrigerant gas while the compressor 36 is operating, the control unit 70 may stop the operation of the compressor 36 and operate the exhaust fan 60.

[0081] With this configuration, when leakage of refrigerant gas is detected, the compressor 36 can be stopped and the exhaust fan 60 can be operated. By operating the exhaust fan 60 when refrigerant gas leaks, the refrigerant gas can be discharged to the outside Rout before the leaked refrigerant gas causes a disproportionation reaction.

[0082] In the above embodiment, an example has been described in which the indoor unit 20C has two sensors 90, 92, but the present invention is not limited to this. The number of sensors may be one, or three or more.

[0083] FIG. 16 is a flowchart showing an example of operation control of an air conditioner according to the first modification of the fifth embodiment. The control unit 70 may stop the operation of the compressor 36 when the detection value of the refrigerant gas by the sensors 90 and 92 exceeds a predetermined threshold value V1, and may stop the operation of the exhaust fan 60 a predetermined period after the operation of the compressor 36 is stopped. In the modification shown in FIG. 16, the exhaust fan 60 operates while the compressor 36 is operating. When the detection value of the refrigerant gas by the sensors 90 and 92 exceeds the predetermined threshold value V1 at time t7, the control unit 70 stops the operation of the compressor 36. At this time, the control unit 70 may stop the operation of the indoor fan 24. After a predetermined period has elapsed from time t7, the control unit 70 may stop the operation of the ventilation fan at time t8. With this configuration, the exhaust fan 60 operates for a while after the detection of the refrigerant gas, so that the air inside the indoor unit can continue to be discharged to the outdoor Rout even after the compressor 36 is stopped, and leakage of the refrigerant into the indoor Rin can be prevented.

[0084] (Outline of the embodiment) (1) The air conditioner disclosed herein is an air conditioner that uses a refrigerant containing an ethylene-based fluoroolefin, and comprises: an outdoor unit having an outdoor heat exchanger, a compressor, and an expansion valve; a housing provided with an indoor air inlet and outlet; an indoor fan disposed within the housing to form an airflow from the inlet to the outlet; and an indoor unit having the indoor heat exchanger located in the airflow path; refrigerant piping that connects the outdoor heat exchanger, the compressor, the expansion valve, and the indoor heat exchanger and through which the refrigerant circulates; an exhaust fan that exhausts air inside the indoor unit to the outside; and a controller that controls the outdoor unit, the indoor unit, and the exhaust fan, and the exhaust fan is configured to exhaust air to the outside from an exhaust inlet provided inside the indoor unit housing and outside the airflow path.

[0085] (2) In the air conditioner of (1), the control unit may operate the exhaust fan while the compressor is in operation.

[0086] (3) In the air conditioner of (1) or (2), the exhaust fan may be operated for a predetermined period of time after the compressor is stopped.

[0087] (4) In any one of the air conditioners (1) to (3), the refrigerant piping may have a plurality of heat transfer tubes arranged in a housing of the indoor unit, a plurality of first bend tubes connecting one ends of the plurality of heat transfer tubes, and a plurality of second bend tubes connecting the other ends of the plurality of heat transfer tubes, the exhaust suction port is arranged in at least one of a first space in which the plurality of first bend tubes are arranged or a second space in which the plurality of second bend tubes are arranged, and the exhaust fan is arranged in the indoor unit and configured to exhaust air inside the housing from the exhaust suction port.

[0088] (5) In the air conditioner of (4), the exhaust suction port may include a first suction port arranged in the first space and a second suction port arranged in the second space, and the indoor unit may further have a first switching unit that switches between opening and closing the first suction port and a second switching unit that switches between opening and closing the second suction port.

[0089] (6) In any one of the air conditioners (1) to (5), the indoor unit further has an air filter through which indoor air passing from the room toward the indoor heat exchanger passes, and a dust collection section that collects and stores dust adhering to the air filter, and the exhaust suction port further includes a third suction port provided in the dust collection section, and the dust collection section is configured to collect dust on the air filter when the indoor fan is not operating, and the control section may operate the exhaust fan when the indoor fan is not operating to suck in dust through the third suction port and discharge it outside the room.

[0090] (7) In the air conditioner of any one of (1) to (3), the outdoor unit may be equipped with a ventilation device that exhausts indoor air from the room to the outside, and the exhaust fan may be disposed in the ventilation device.

[0091] (8) In any one of the air conditioners (1) to (7), the indoor unit may further have a sensor that detects refrigerant gas inside the housing, and the control unit may stop operation of the compressor and operate the exhaust fan when the sensor detects the refrigerant gas while the compressor is operating.

[0092] (9) In the air conditioner of any one of (1) to (8), the ethylene-based fluoroolefin may include an ethylene-based fluoroolefin that undergoes a disproportionation reaction.

[0093] (10) In the air conditioner of any one of (1) to (9), the ethylene-based fluoroolefin may be 1,1,2-trifluoroethylene, trans-1,2-difluoroethylene, cis-1,2-difluoroethylene, 1,1-difluoroethylene, tetrafluoroethylene, or monofluoroethylene.

[0094] (11) In the air conditioner of any one of (1) to (10), the refrigerant may further contain difluoromethane.

[0095] (12) In the air conditioner of any one of (1) to (11), the refrigerant may further contain saturated hydrocarbons. [Industrial Applicability]

[0096] The present disclosure is applicable to air conditioners that use refrigerants containing ethylene-based fluoroolefins. [Explanation of symbols]

[0097] 10, 110 Air conditioner 20, 20A~20C, 120 indoor unit 22 Indoor heat exchanger 24 Indoor fan 28 Case 30, 130 outdoor unit 32 Outdoor heat exchanger 34 Fans 36 Compressor 38 Expansion valve 40 Four-way valve 50 Refrigerant piping 52 Heat transfer tube 54 First Bend Pipe 56 Second Bend Pipe 60 Exhaust fan 64 Exhaust Duct 66 1st switching section 67 2nd switching section 70 Control section 80 Air Filter 82 Dust collection section 90, 92 Sensors 92 Sensors 150 Ventilation Equipment 156 Ventilation Hose 160 Exhaust fan

Claims

1. An air conditioner that uses a refrigerant containing an ethylene-based fluoroolefin, an outdoor unit having an outdoor heat exchanger, a compressor, and an expansion valve; an indoor unit including a housing provided with an indoor air intake port and an exhaust port, an indoor fan disposed within the housing and forming an airflow from the intake port to the exhaust port, and an indoor heat exchanger located on a path of the airflow; a refrigerant pipe that connects the outdoor heat exchanger, the compressor, the expansion valve, and the indoor heat exchanger and through which the refrigerant circulates; An exhaust fan that exhausts air from inside the indoor unit to the outside; A control unit that controls the outdoor unit, the indoor unit, and the exhaust fan; Equipped with The exhaust fan is configured to exhaust air to the outside of the room from an exhaust suction port provided inside the housing of the indoor unit and outside the airflow path. Air conditioner.

2. The control unit operates the exhaust fan while the compressor is in operation. The air conditioner according to claim 1.

3. The control unit operates the exhaust fan for a predetermined period of time after the operation of the compressor is stopped. The air conditioner according to claim 1.

4. The refrigerant piping includes a plurality of heat transfer tubes arranged in the housing of the indoor unit, a plurality of first bend tubes connecting one ends of the plurality of heat transfer tubes to each other, and a plurality of second bend tubes connecting the other ends of the plurality of heat transfer tubes to each other, the exhaust suction port is disposed in at least one of a first space in which the plurality of first bend pipes are disposed or a second space in which the plurality of second bend pipes are disposed, The exhaust fan is disposed in the indoor unit and configured to exhaust air inside the housing through the exhaust suction port. The air conditioner according to claim 1.

5. The exhaust suction port includes a first suction port disposed in the first space and a second suction port disposed in the second space, The indoor unit further includes a first switching unit that switches between opening and closing the first suction port, and a second switching unit that switches between opening and closing the second suction port. The air conditioner according to claim 4.

6. The indoor unit further includes an air filter through which indoor air passing from the room toward the indoor heat exchanger passes, and a dust collection section that collects and stores dust adhering to the air filter, The exhaust suction port further includes a third suction port provided in the dust collecting portion, The dust collecting unit is configured to collect dust on the air filter when the indoor fan is not operating, The control unit operates the exhaust fan when the indoor fan is not operating, to suck in dust from the third suction port and discharge the dust to the outside. The air conditioner according to claim 1.

7. The outdoor unit includes a ventilation device that exhausts indoor air from inside the room to outside the room, The exhaust fan is disposed in the ventilation device. The air conditioner according to claim 1.

8. The indoor unit further includes a sensor for detecting refrigerant gas inside the housing, The control unit stops the operation of the compressor and operates the exhaust fan when the sensor detects the refrigerant gas during operation of the compressor. The air conditioner according to claim 1.

9. The ethylene-based fluoroolefin includes an ethylene-based fluoroolefin that undergoes a disproportionation reaction.

2. The air conditioner of claim 1.

10. The ethylenic fluoroolefin is 1,1,2-trifluoroethylene, trans-1,2-difluoroethylene, cis-1,2-difluoroethylene, 1,1-difluoroethylene, tetrafluoroethylene, or monofluoroethylene; 2. The air conditioner of claim 1.

11. The refrigerant further comprises difluoromethane.

2. The air conditioner of claim 1.

12. The refrigerant further comprises a saturated hydrocarbon.

2. The air conditioner of claim 1.

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