Patent Application
20240401827
The present disclosure relates to an air-conditioning apparatus including a shut-off valve.
Patent Literature 1 discloses an air-conditioning apparatus that closes, when detecting a leak of refrigerant, a solenoid valve and a shut-off valve in order to reduce further occurrence of the refrigerant leak. To be more specific, the air-conditioning apparatus according to Patent Literature 1 includes an electromagnetic expansion valve and a shut-off valve that are provided in the following manner. The electromagnetic expansion valve is provided in a refrigerant circuit that is located between an outdoor heat exchanger and an indoor heat exchanger such that no compressor is interposed between the outdoor heat exchanger and the indoor heat exchanger. The shut-off valve is provided in a refrigerant circuit that is located between an outdoor heat exchanger and an indoor heat exchanger, with a compressor interposed between the outdoor heat exchanger and the indoor heat exchanger. Patent Literature 1 proposes use of a controller that closes the electromagnetic expansion valve to cause refrigerant to collect on an outdoor heat exchanger side, when a leak of refrigerant is detected, and then closes the shut-off valve.
In some cases, if refrigerant leaks from an air-conditioning apparatus, further occurrence of such a refrigerant leak is reduced using, for example, the controller described in Patent Literature 1, the air-conditioning apparatus is stopped, and a component of the air-conditioning apparatus is then repaired or replaced by a new one. In this case, it is necessary to find a location at which the refrigerant leak occurs. Furthermore, in the case of repairing or replacing a component of the air-conditioning apparatus, in some cases, the refrigerant is drawn out from the air-conditioning apparatus, the component is repaired or replaced by a new one, and refrigerant is then re-filled into the air-conditioning apparatus. This, however, causes the following problem related to the maintainability of the air-conditioning apparatus: refrigerant pipes have no part that allows connection of external equipment such as, a temperature sensor, a pressure sensor, a pump for drawing the refrigerant, a pump for re-filing refrigerant, and a vacuum pump. Inevitably, it takes time to, for example, find a location where a refrigerant leak occur, draw out refrigerant, and re-fill refrigerant.
The present disclosure is applied in view of the above circumstances, and relates to an air-conditioning apparatus that is improved in maintainability.
An air-conditioning apparatus according to an embodiment of the present disclosure includes: an outdoor unit including a compressor and an outdoor heat exchanger, and configured to generate cooling energy or heating energy; an indoor unit including an indoor heat exchanger, and configured to perform an air-conditioning operation with the cooling energy or the heating energy that is generated by the outdoor unit; a refrigerant pipe provided between the outdoor unit and the indoor unit, and forming a refrigerant circuit in which refrigerant circulates; and a shut-off valve provided at the refrigerant pipe, and configured to be closed when a refrigerant leak is detected. The shut-off valve includes a service port communicating with the refrigerant pipe.
The air-conditioning apparatus according to an embodiment of the present disclosure includes a shut-off valve having a service port communicating with a refrigerant pipe. It is therefore possible to connect external equipment with the refrigerant pipe by attaching the external equipment to the service port. Thus, maintenance can be performed on the air-conditioning apparatus, with the external equipment attached to the service port, whereby the maintainability of the air-conditioning apparatus can be improved.
Air-conditioning apparatuses according to the embodiments will be described below with reference to the drawings. Descriptions of the present disclosure that concern the embodiments described below are not limiting but various modifications can be made without departing from the scope and spirit of the present disclosure. The present disclosure may encompass all possible combinations of configurations as described below regarding the embodiments. The drawings illustrate examples of configurations of the air-conditioning apparatuses, and do not limit the configurations described in the present disclosure. Although directional terms (for example, “upper” and “lower”) are used as appropriate in order that the embodiments be more easily understood, they are not limiting. In addition, in each of the figures in the drawings, components that are the same as or equivalent to those in a previous figure or previous figures are denoted by the same reference signs. The same is true of the entire text of the specification. In each of the figures, relative dimensions, shapes, or other features of components may differ from actual ones.
As illustrated in
In the following description, the indoor-unit-side shut-off valve 30a and the outdoor-unit-side shut-off valve 30b are each simply referred to as “shut-off valve 30” as appropriate in the case where they do not particularly need to be distinguished from each other. The following description is also made assuming that the term “shut-off valve 30” is applicable to both a single shut-off valve 30 and plural shut-off valves 30.
The air-conditioning apparatus 100 includes indoor-unit-side shut-off valves 30a that are provided at respective refrigerant pipes 10, that is, the refrigerant pipe 10 connected to the indoor unit 2a, the refrigerant pipe 10 connected to the indoor unit 2b, and the refrigerant pipe 10 connected to the indoor unit 2c. To be more specific, as illustrated in
The air-conditioning apparatus 100 includes outdoor-unit-side shut-off valves 30b provided at respective refrigerant pipes 10 connected to the outdoor unit 3. To be more specific, as illustrated in
As illustrated in
The outdoor heat exchanger 7 causes heat exchange to be performed between the refrigerant and air (hereinafter referred to as “outdoor air” as appropriate) supplied by an air-sending device such as a fan (not illustrated). Specifically, in the cooling operation, the outdoor heat exchanger 7 serves as a condenser that transfers the heat of the refrigerant to the outdoor air to thereby condense the refrigerant. In the heating operation, the outdoor heat exchanger 7 serves as an evaporator that evaporates the refrigerant to thereby cool the outdoor air with the heat of vaporization.
The refrigerant flow switching device 9 is, for example, a four-way valve. The refrigerant flow switching device 9 is capable of switching the operation of the air-conditioning apparatus 100 between the cooling operation and the heating operation by switching the flow direction of the refrigerant between plural flow directions. The refrigerant flow switching device 9 is not limited to the four-way valve but may be a combination of two-way valves, three-way valves, or other valves.
The accumulator 25 is connected to a suction side of the compressor 6. By the switching operation of the refrigerant flow switching device 9, the accumulator 25 is connected to the downstream side of the outdoor heat exchanger 7 in the heating operation. The accumulator 25 is connected to the downstream side of an indoor heat exchanger 4 in the cooling operation. The accumulator 25 is a container that stores surplus refrigerant, and absorbs the difference in refrigerant flow rate between the cooling operation and the heating operation. The outdoor unit 3 may include no accumulator 25.
The expansion valve 8 reduces the pressure of refrigerant that flows from the indoor units 2a, 2b, and 2c in the heating operation. In the case where the air-conditioning apparatus 100 is used for the cooling operation only, the outdoor unit 3 may include no expansion valve 8. In the case where the indoor units 2a, 2b, and 2c include respective expansion valves 5, as a configuration in which no expansion valve 8 is provided, the expansion valve 5 may be used to fulfill the function of the expansion valve 8.
The indoor units 2a, 2b, and 2c are installed in spaces 1a, 1b, and 1c, respectively, which are air-conditioning target spaces. The indoor units 2a, 2b, and 2c supply air for cooling or air for heating to the spaces 1a, 1b, and 1c, respectively, using the cooling energy or heating energy of refrigerant that circulates through the refrigerant pipe 10. The indoor units 2a, 2b, and 2c include respective indoor heat exchangers 4 and respective expansion valves 5. Although
The indoor heat exchanger 4 in each of the indoor units 2a, 2b, and 2c causes heat exchange to be performed between air supplied by an air-sending device such as a fan (not illustrated) and refrigerant, thereby obtaining air for cooling or air for heating, which is to be supplied to an associated one of the spaces 1a, 1b, and 1c. Specifically, when the refrigerant carries cooling energy in the cooling operation, the indoor heat exchanger 4 operates as an evaporator to perform the cooling operation by cooling the air in the associated one of the spaces 1a, 1b, and 1c, which are air-conditioning target spaces. When the refrigerant carries heating energy in the heating operation, the indoor heat exchanger 4 operates as a condenser to perform the heating operation by heating the air in the associated one of the spaces 1a, 1b, and 1c, that is, air-conditioning target spaces.
The expansion valve 5 in each of the indoor unit 2a, 2b, and 2c reduces the pressure of refrigerant that flows from the indoor-unit-side shut-off valve 30a in the cooling operation. In the case where the air-conditioning apparatus 100 is used for the heating operation only, the indoor unit 2 may include no expansion valve 5. In the case where the outdoor unit 3 includes the expansion valve 8, preferably, the indoor units 2a, 2b, and 2c should include respective expansion valves 5 for adjustment of the capacities of the respective indoor units 2. However, in the case where each of these indoor units is designed to include no expansion valve 5, the expansion valve 8 may be used to fulfill the function of the expansion valve 5.
The air-conditioning apparatus 100 includes refrigerant leak detection devices 15a, 15b, and 15c to detect a refrigerant leak in the spaces 1a, 1b, and 1c where the indoor units 2a, 2b, and 2c are provided, respectively. Each of the refrigerant leak detection devices 15a, 15b, and 15c is, for example, a gas sensor configured to detect a refrigerant leak by detecting the concentration of refrigerant or the concentration of oxygen. For example, when it is detected that the concentration of the refrigerant is higher than or equal to a threshold value, it is determined that a refrigerant leak occurs. Furthermore, when the concentration of oxygen reaches a threshold value or less, it is determined that a refrigerant leak occurs. In addition, it may be detected whether a refrigerant leak occurs or not, by detecting both the concentration of refrigerant and the concentration of oxygen. Instead of or in addition to the gas sensor, a pressure sensor that detects a pressure in the refrigerant pipe 10 may be provided as each of the refrigerant leak detection devices 15a, 15b, and 15c. When a refrigerant leak occurs, the pressure in the refrigerant pipe 10 drops. Thus, a value detected by the pressure sensor can be used as information for determining whether a refrigerant leak occurs or not. Although the pressure in the refrigerant pipe 10 varies depending on the operating state of the air-conditioning apparatus 100, it is possible to detect the possibility that a refrigerant leak will occur, by using a pressure in a specific operating state as a reference value. In the following description, the refrigerant leak detection devices 15a, 15b, and 15c are simply referred to as “refrigerant leak detection device 15” as appropriate in the case where they do not particularly need to be distinguished from each other. Furthermore, the following description is also made assuming that the term “refrigerant leak detection device 15” is applicable to both a single refrigerant leak detection device 15 and plural refrigerant leak detection devices 15; and the spaces 1a, 1b, and 1c are each simply referred to as “space 1” as appropriate in the case where they do not particularly need to be distinguished from each other.
Furthermore, the following description is also made assuming that the term “space 1” is applicable to both a single space 1 and plural spaces 1.
The air-conditioning apparatus 100 is provided with a controller 20. The controller 20 is, for example, software to be run on a computing unit such as a microcomputer or a central processing unit (CPU), or hardware such as a circuit device that fulfills various functions. The controller 20 controls the operation of the entire air-conditioning apparatus 100. A signal line of the shut-off valve 30 is connected to the controller 20. For example, the controller 20 may perform an opening and closing control of the shut-off valve 30 by switching the state of the shut-off valve 30 between energized and de-energized states. A signal line of the refrigerant leak detection device 15 is connected to the controller 20. Information detected by the refrigerant leak detection device 15 is input to the controller 20.
The controller 20 performs a control when the refrigerant leak detection device 15 detects a refrigerant leak. Dashed lines extended from the controller 20 as illustrated in
As illustrated in
The valve body 37 is movable in the flow passage 38 to open and close the flow passage 38. In Embodiment 1, the valve body 37 is provided in part of the flow passage 38 that extends in an up-down direction. The valve body 37 can be moved up and down. When the air-conditioning apparatus 100 is in the stopped state, the valve bodies 37 of all the shut-off valves 30 are moved down to a closed position P where the valve bodies 37 shuts off the passages 38. In the case where the air-conditioning apparatus 100 includes plural indoor units 2, in some cases, one of the indoor units 2 is in operation and another one of the indoor units 2 is in the stopped state. For example, in the air-conditioning apparatus 100 as illustrated in
The indoor-unit-side connection pipe 32a is fit in the first opening 38a4 provided in the block body 31. The outdoor-unit-side connection pipe 32b is fit in the second opening 38a5 provided in the block body 31. The indoor-unit-side connection pipe 32a is connected to the refrigerant pipe 10 connected to the indoor unit 2. The outdoor-unit-side connection pipe 32b is connected to the refrigerant pipe 10 connected to the outdoor unit 3. The flow passage 38 connecting the indoor-unit-side connection pipe 32a and the outdoor-unit-side connection pipe 32b is provided in the block body 31. A fluid can flow through the flow passage 38 from the outdoor-unit-side connection pipe 32b toward the indoor-unit-side connection pipe 32a, or from the indoor-unit-side connection pipe 32a toward the outdoor-unit-side connection pipe 32b. The flow passage 38 is shut off when the valve body 37 is moved down to the closed position P. The flow passage 38 is in the open state when the valve body 37 is located above the closed position P.
In the following description, the indoor-unit-side connection pipe 32a and the outdoor-unit-side connection pipe 32b are simply referred to as “connection pipe 32” as appropriate in the case where they do not particularly need to be distinguished from each other. The following description is also made assuming that the term “connection pipe 32” is applicable to both a single connection pipe 32 and plural connection pipes 32.
As illustrated in
The communication between the main flow passage 38a1 and the main flow passage 38a2 is shut off when the valve body 37 is located in the closed position P. The closed position P of the valve body 37 corresponds to a position where the main-passage communication part 38a3 and the main flow passage 38a2 are connected with each other. The main flow passage 38a2 is too narrow in width to allow the valve body 37 to move therein. The main flow passage 38a2 is connected with the lower end of the main-passage communication part 38a3. Consequently, when the valve body 37 is moved down in the main-passage communication part 38a3, the valve body 37 cannot be further moved down to a position located below the position where the main-passage communication part 38a3 and the main flow passage 38a2 connect with each other. That is, in this state, the valve body 37 blocks the space between the main-passage communication part 38a3 and the main flow passage 38a2. The main flow passage 38a1 is connected to the main-passage communication part 38a3 at a position located above the closed position P of the valve body 37. Thus, when the valve body 37 is stopped at the closed position P, the valve body 37 blocks the space between the main flow passage 38a1 and the main-passage communication part 38a3.
Next, it will be described how the air-conditioning apparatus 100 having the above configuration is operated in the cooling operation and in the heating operation, based on the flow of the refrigerant. In the air-conditioning apparatus 100 according to Embodiment 1, all of the indoor units 2a, 2b, and 2c may perform the cooling operation or all of the indoor units 2a, 2b, and 2c may perform the heating operation.
The following description is made regarding the case where the indoor units 2a, 2b, and 2c perform the cooling operation, with reference to the solid arrows indicated in
After flowing out from the outdoor heat exchanger 7, the liquid refrigerant flows out from the outdoor unit 3. The liquid refrigerant that has flowed out from the outdoor unit 3 flows into the outdoor-unit-side connection pipe 32b of the outdoor-unit-side shut-off valve 30b-1. The liquid refrigerant that has flowed into the outdoor-unit-side connection pipe 32b of the outdoor-unit-side shut-off valve 30b-1 flows through the flow passage 38 of the outdoor-unit-side shut-off valve 30b-1, and flows out from the indoor-unit-side connection pipe 32a of the outdoor-unit-side shut-off valve 30b-1. The liquid refrigerant that has flowed out from the indoor-unit-side connection pipe 32a of the outdoor-unit-side shut-off valve 30b-1 flows through the refrigerant pipe 10, and flows into the outdoor-unit-side connection pipe 32b of each of the indoor-unit-side shut-off valves 30a-1, 30a-3, and 30a-5. The liquid refrigerant that has flowed into the outdoor-unit-side connection pipe 32b of each of the indoor-unit-side shut-off valves 30a-1, 30a-3, and 30a-5 flows through the flow passage 38 of that indoor-unit-side shut-off valve, and flows out from the indoor-unit-side connection pipe 32a of the indoor-unit-side shut-off valve.
The liquid refrigerant that has flowed out from each of the indoor-unit-side shut-off valves 30a-1, 30a-3, and 30a-5 is reduced in pressure by the expansion valve 5 in an associated one of the indoor units 2a, 2b, and 2c, and then flows into an associated one of the indoor heat exchangers 4. The refrigerant that has flowed into the indoor heat exchanger 4 exchanges heat with indoor air to receive heat therefrom and evaporate, thereby cooling the indoor air, and thus changes into gas refrigerant. The gas refrigerant flows out from the indoor heat exchanger 4.
The gas refrigerant that has flowed out from each of the indoor heat exchangers 4 flows into the indoor-unit-side connection pipe 32a of an associated one of the indoor-unit-side shut-off valves 30a-2, 30a-4, and 30a-6. The gas refrigerant that has flowed into the indoor-unit-side connection pipe 32a of the above indoor-unit-side shut-off valve flows through the flow passage 38 of the above indoor-unit-side shut-off valve, and flows out from the outdoor-unit-side connection pipe 32b of the indoor-unit-side shut-off valve. The gas refrigerant that has flowed out form the outdoor-unit-side connection pipe 32b of the indoor-unit-side shut-off valve flows through the refrigerant pipe 10, and flows into the indoor-unit-side connection pipe 32a of the outdoor-unit-side shut-off valve 30b-2. The gas refrigerant that has flowed into the indoor-unit-side connection pipe 32a of the outdoor-unit-side shut-off valve 30b-2 flows through the flow passage 38 of the outdoor-unit-side shut-off valve 30b-2, and flows out from the outdoor-unit-side connection pipe 32b of the outdoor-unit-side shut-off valve 30b-2. The gas refrigerant that has flowed out from the outdoor-unit-side connection pipe 32b of the outdoor-unit-side shut-off valve 30b-2 flows through the refrigerant pipe 10, and flows into the outdoor unit 3.
The gas refrigerant that has flowed into the outdoor unit 3 returns to the compressor 6 after flowing through the refrigerant flow switching device 9 and the accumulator 25. In the cooling operation, the circulation of refrigerant as described above is repeated.
It will be described how the refrigerant flows in a heating main operation. The description is made regarding the case where the indoor units 2a, 2b, and 2c perform the heating operation, with reference to the dashed arrows indicated in
The refrigerant that has flowed out from the outdoor unit 3 flows through the refrigerant pipe 10 and flows into the outdoor-unit-side connection pipe 32b of the outdoor-unit-side shut-off valve 30b-2. The refrigerant that has flowed into the outdoor-unit-side connection pipe 32b of the outdoor-unit-side shut-off valve 30b-2 flows through the flow passage 38 of the outdoor-unit-side shut-off valve 30b-2, and flows out from the indoor-unit-side connection pipe 32a of the outdoor-unit-side shut-off valve 30b-2. The refrigerant that has flowed out from the indoor-unit-side connection pipe 32a of the outdoor-unit-side shut-off valve 30b-2 flows through the refrigerant pipe 10 and flows into the outdoor-unit-side connection pipe 32b of each of the indoor-unit-side shut-off valves 30a-2, 30a-4, and 30a-6.
The refrigerant that has flowed into the outdoor-unit-side connection pipe 32b of each of the indoor-unit-side shut-off valves 30a-2, 30a-4, and 30a-6 flows through the flow passage 38 of that indoor-unit-side shut-off valve, and flows out from the indoor-unit-side connection pipe 32a of the indoor-unit-side shut-off valve. The refrigerant that has flowed out from the indoor-unit-side connection pipe 32a of the indoor-unit-side shut-off valve flows into the indoor heat exchanger 4 in an associated one of the indoor units 2a to 2c.
The refrigerant that has flowed into the indoor heat exchanger 4 exchanges heat with indoor air to condense while transferring heat to the indoor air, thereby heating the indoor air, and thus changes into liquid refrigerant. The liquid refrigerant then flows out from the indoor heat exchanger 4. The liquid refrigerant that has flowed out form the indoor heat exchanger 4 flows through the expansion valve 5 that is provided in an associated one of the indoor units 2a to 2c and that is in the open state, and then flows into the indoor-unit-side connection pipe 32a of an associated one of the indoor-unit-side shut-off valves 30a-1, 30a-3, and 30a-5. The liquid refrigerant that has flowed into the indoor-unit-side connection pipe 32a of the above indoor-unit-side shut-off valve flows through the flow passage 38 of the indoor-unit-side shut-off valve, and flows out from the outdoor-unit-side connection pipe 32b of the indoor-unit-side shut-off valve.
The liquid refrigerant that has flowed out from the outdoor-unit-side connection pipe 32b flows through the refrigerant pipe 10 and flows into the indoor-unit-side connection pipe 32a of the outdoor-unit-side shut-off valve 30b-1. The liquid refrigerant that has flowed into the indoor-unit-side connection pipe 32a of the outdoor-unit-side shut-off valve 30b-1 flows through the flow passage 38 of the outdoor-unit-side shut-off valve 30b-1 and flows out from the outdoor-unit-side connection pipe 32b of the outdoor-unit-side shut-off valve 30b-1. The liquid refrigerant that has flowed out from the outdoor-unit-side connection pipe 32b of the outdoor-unit-side shut-off valve 30b-1 flows through the refrigerant pipe 10 and flows into the outdoor unit 3. The liquid refrigerant that has flowed into the outdoor unit 3 is reduced in pressure by the expansion valve 8 and flows into the outdoor heat exchanger 7. The refrigerant that has flowed into the outdoor heat exchanger 7 exchanges heat with indoor air to receive heat therefrom and evaporate and thus gasifies, and the refrigerant flows out from the outdoor heat exchanger 7. The refrigerant that has flowed out from the outdoor heat exchanger 7 flows through the refrigerant flow switching device 9 and the accumulator 25 and returns to the compressor 6. In the heating operation, the above circulation of the refrigerant is repeated.
In the air-conditioning apparatus 100 according to Embodiment 1, plural shut-off valves 30 may be formed as a single shut-off valve unit 300.
For example, plural shut-off valves 30 connected to the same indoor unit 2 can be provided as a shut-off valve unit 300. Therefore, in the air-conditioning apparatus 100 as illustrated in
As illustrated in
The shut-off valves 30 of the air-conditioning apparatus 100 according to Embodiment 1 includes the service ports 50. The service port 50 will be described with reference to
As illustrated in
The connection part 52 of the service port 50 has a tubular shape, and connects the tip 51 of the service port 50 and the flow passage 38 of the shut-off valve 30. Thus, the external equipment inserted from the tip 51 can be moved to the flow passage 38 of the shut-off valve 30 through the connection part 52.
The number of service ports 50 and the installation positions of the service ports 50, however, are not limited to those as illustrated in
It is not indispensable that the service port 50 is provided in the block body 31 of the shut-off valve 30. As illustrated in
Referring to
External equipment for use in maintenance of the air-conditioning apparatus 100 can be directly connected to the tip 51 of the service port 50. The maintenance of the air-conditioning apparatus 100 means work such as installation, removal, relocation, repair, modification, and inspection of the air-conditioning apparatus 100. As external equipment, for example, a pressure sensor, a device for drawing refrigerant, a vacuum pump, and a tank for re-filing refrigerant. Also, as external equipment, a connection hose may be directly connected to the tip 51. In the case where the external equipment cannot be directly connected to the tip 51, it suffices that the external equipment is connected to a connection hose connected to the tip 51. Therefore, in the maintenance of the air-conditioning apparatus 100, necessary external equipment can be connected via the hose directly connected to the tip 51. Furthermore, the external equipment can be inserted from the tip 51, not being directly connected to the tip 51. By inserting a sensor such as a pressure sensor or a temperature sensor from the tip 51, and moving the inserted sensor to the refrigerant pipe 10, it is possible to acquire information on the inside of the refrigerant pipe 10.
With reference to
As illustrated in
The indoor-unit-side shut-off valve 30a-1, the indoor-unit-side shut-off valve 30a-2, the outdoor-unit-side shut-off valve 30b-1, and the outdoor-unit-side shut-off valve 30b-2 have respective service ports 50 each of which is provided at a location where the service port 50 communicates with the indoor-unit-side connection pipe 32a when the flow passage 38 is blocked by the valve body 37.
When a refrigerant leak is detected by the refrigerant leak detection device 15 of the air-conditioning apparatus 100, each of the shut-off valves 30 are closed. As a result, the first region AR1, the second region AR2, and the third region AR3 are isolated from each other. After a refrigerant leak is detected, when the air-conditioning apparatus 100 is deactivated, and a value of the pressure in the refrigerant pipe 10 is measured by a pressure sensor, in a region where a refrigerant leak does not occur, the value detected by the pressure sensor does not change from the time when the air-conditioning apparatus 100 is deactivated. In contrast, in a region where a refrigerant leak occurs, the value detected by the pressure sensor becomes close to the atmosphere pressure. Therefore, as illustrated in
In the case where refrigerant leaks at the refrigerant leak position LP, the value detected by the pressure sensor 60 connected to the service port 50 of the outdoor-unit-side shut-off valve 30b-1 is close to the atmospheric pressure. In
In the case where the refrigerant leak position LP can be determined, the pressure sensor 60 connected to the service port 50 of the outdoor-unit-side shut-off valve 30b-1 is removed, and then external equipment necessary for repairing the air-conditioning apparatus 100 can be connected to the service port 50.
The vacuum pump 61 as illustrated in
The air-conditioning apparatus 100 according to Embodiment 1 includes the outdoor unit 3, the indoor unit 2, the refrigerant pipes 10, and the shut-off valves 30. The outdoor unit 3 includes the compressor 6, and the outdoor heat exchanger 7, and generates cooling energy or heating energy. The indoor unit 2 includes the indoor heat exchanger 4, and performs an air-conditioning operation with the cooling energy or the heating energy that is generated in the outdoor unit 3. The refrigerant pipes 10 are provided between the outdoor unit 3 and the indoor unit 2 and included in a refrigerant circuit in which refrigerant circulates. The shut-off valves 30 are provided at the refrigerant pipes 10, and are closed when it is detected that a refrigerant leak occurs. The shut-off valves 30 each have the service port 50 that communicates with the refrigerant pipe 10.
In the above configuration, external equipment can be inserted into the refrigerant pipe 10 via the service port 50. That is, it is possible to use necessary external equipment via the service port 50 at the time of performing maintenance of the air-conditioning apparatus 100, and thus possible to improve the maintainability of the air-conditioning apparatus 100.
The service ports 50 of the air-conditioning apparatus 100 according to Embodiment 1 each have the tip 51 that can be opened and closed and allows external equipment to be attached to and detached from the tip 51. The tip 51 is opened when the external equipment is connected to the tip 52. As a result, a pressure sensor, a device for drawing refrigerant, a vacuum pump, a tank for re-filing refrigerant, and a connection hose can be directly or indirectly connected to the service port 50.
The shut-off valves 30 according to Embodiment 1 each include the block body 31 and the valve body 37. The block body 31 includes the passages 38 that communicate with refrigerant pipes 10. In the valve body 37, each of the flow passage 38 is made to be opened or closed. The service port or ports 50 are provided at the block body 31 in such a manner as to communicate with the passages 38. In this configuration, the service ports 50 are provided in the block body 31 that is sturdier than the pipe. Therefore, even when a load acts on the service port 50, the effect of the load on the service port 50 may be reduced.
The shut-off valves 30 according to Embodiment 1 each include the block body 31, the valve body 37, and the connection pipes 32. The block body 31 includes the passages 38 that communicate with the refrigerant pipes 10. In the valve body 37, each of the flow passage 38 is made to be opened or closed. The connection pipes 32 are connected to the passages 38, and protrudes from the block body 31. The connection pipes 32 are connected to the refrigerant pipes 10. The service ports 50 are provided at the connection pipes 32. In the above configuration, the service ports 50 are provided at the connection pipes 32 of the shut-off valves 30, which are pipes directly connected to the refrigerant pipes 10. Therefore, when external equipment needs to be inserted all the way into the refrigerant pipe 10, this insertion can be relatively easily performed. It is therefore possible to further improve the maintainability of the air-conditioning apparatus 100.
Furthermore, in Embodiment 1, plural shut-off valves 30 are provided at the refrigerant pipe 10. The shut-off valves 30 include the indoor-unit-side shut-off valves 30a and the outdoor-unit-side shut-off valves 30b. The indoor-unit-side shut-off valves 30a are located closer to the indoor unit 2 than to the outdoor unit 3. The outdoor-unit-side shut-off valves 30b are located closer to the outdoor unit 3 than to the indoor unit 2. In the above configuration, a region where the refrigerant pipes 10 located between the indoor-unit-side shut-off valve 30a and the outdoor-unit-side shut-off valve 30b are provided can be handled as a single region. In addition, in the maintenance of the air-conditioning apparatus 100, external equipment can be connected to the service port 50 of each of the indoor-unit-side shut-off valve 30a and the outdoor-unit-side shut-off valve 30b. The maintenance can thus be efficiently performed. It is therefore possible to further improve the maintainability of the air-conditioning apparatus 100.
In Embodiment 1, the plural indoor-unit-side shut-off valves 30a are provided. The indoor-unit-side shut-off valves 30a-1 and 30a-2 include the indoor-unit-side shut-off valve 30a-1 that is provided at part of the refrigerant pipe 10 through which the refrigerant passes to flow into the indoor unit 2, and the outdoor-unit-side shut-off valve 30a-2 that is provided at part of the refrigerant pipe 10 through which the refrigerant passes after flowing out from the indoor unit 2. The plural outdoor-unit-side shut-off valves 30b are provided. The outdoor-unit-side shut-off valves 30b-1 and 30b-2 include the outdoor-unit-side shut-off valve 30b-1 that is provided at part of the refrigerant pipe 10 through which the refrigerant passes to flow into the outdoor unit 3, and the outdoor-unit-side shut-off valve 30b-2 that is provided at part of the refrigerant pipe 10 through which the refrigerant passes after flowing out from the outdoor unit 3.
In the above configuration, the inside of the air-conditioning apparatus 100 is divided into the first region AR1 where the indoor unit 2 is installed, the second region AR2 where the refrigerant pipe 10 connecting the indoor unit 2 and the outdoor unit 3 is provided, and the third region AR3 where the outdoor unit 3 is installed, and in this state, the maintenance of the air-conditioning apparatus 100 can be performed. It is therefore possible to perform maintenance on the first to third regions AR1 to AR3 simultaneously, using the service ports 50 associated with these regions. In addition, in the case of offering service to only a region, maintenance can be performed on only the region, using the service port 50 associated with the region. It is therefore possible to shorten the time required for performing maintenance on the air-conditioning apparatus 100, and further improve the maintainability of the air-conditioning apparatus 100.
For example, in air-conditioning apparatuses such as variable refrigerant flow (VRF) systems, the total length of refrigerant pipes connecting an outdoor unit and plural indoor units can be several hundred meters. In the case where the total length of refrigerant pipes is increased, the amount of refrigerant for use in the air-conditioning apparatus is also increased. Therefore, in an air-conditioning apparatus having refrigerant pipes the total length of which is great, in some cases, it takes a long time to determine a location where a refrigerant leak occurs, since it is necessary to check whether the refrigerant leak occurs, over a relatively large region. For this reason, it may sometimes take time to determine a location where a leak occurs. Furthermore, in maintenance, it may sometimes take time to draw back refrigerant, re-fill refrigerant, and evacuate the refrigerant pipes. In this regard, in the air-conditioning apparatus 100 according to Embodiment 1, it is possible to perform maintenance on the first to third regions AR1 to AR3 at the same time, which are provided independently of each other, using the service ports 50. Accordingly, it is possible to check the first to third regions AR1 to AR3 simultaneously as to whether a refrigerant leak occurs or not. In addition, it is possible to perform an operation for drawing back refrigerant, an operation for re-filling refrigerant, and an operation for evacuation, on the first to third regions AR1 to AR3, at the same time. Furthermore, it is also possible to perform different maintenance operations on the regions at the same time. The maintainability of the air-conditioning apparatus 100 is thus further improved.
The shut-off valves 30 and the air-conditioning apparatus 100 according to Embodiment 2 will be described. In the air-conditioning apparatus 100 according to Embodiment 2, the outdoor unit 3 includes plural check valves 16a, 16b, 16c, and 16d; and a relay unit 17 is installed between the outdoor unit 3 and plural indoor units 2. In this regard, the air-conditioning apparatus 100 according to Embodiment 2 is different in configuration from the air-conditioning apparatus 100 according to Embodiment 1. It should be noted that regarding Embodiment 2, components that are the same as those in Embodiment 1 will be denoted by the same reference signs and their description will thus be omitted.
As illustrated in
In the air-conditioning apparatus 100 according to Embodiment 2, it is possible to activate an indoor unit that performs the cooling operation and an indoor unit that performs the heating operation at the same time. In the entire air-conditioning apparatus, when a cooling load on the indoor unit that performs the cooling operation exceeds a heating load on the indoor unit that performs the heating operation, a cooling main operation is performed. In contrast, when the heating load on the indoor unit that performs the heating operation exceeds the cooling load on the indoor unit that performs the cooling operation, a heating main operation is performed. When the cooling main operation is performed as the cooling load exceeds the heating load, for example, the number of indoor units that perform the cooling operation is larger than that of indoor units that perform the heating operation. In contrast, when the heating main operation is performed as the heating load exceeds the cooling load, the number of indoor units that perform the heating operation is larger than that of indoor units that perform the cooling operation.
In
As illustrated in
The relay unit 17 is provided between the outdoor unit 3 and the indoor-unit-side shut-off valves 30a-1 to 30a-6. The outdoor unit 3 and the relay unit 17 are connected by refrigerant pipes 10. The refrigerant pipes 10 between the outdoor unit 3 and the relay unit 17 include a refrigerant-pipe communication part 10a and a refrigerant-pipe communication part 10b. Refrigerant that flows from the outdoor unit 3 to the relay unit 17 passes through the refrigerant-pipe communication part 10a. Refrigerant that flows from the relay unit 17 to the outdoor unit 3 passes through the refrigerant-pipe communication part 10b. The outdoor-unit-side shut-off valve 30b-1 is provided at the refrigerant-pipe communication part 10a. The outdoor-unit-side shut-off valve 30b-2 is provided at the refrigerant-pipe communication part 10b.
The indoor-unit-side shut-off valves 30a-1 to 30a-6 are provided at the refrigerant pipes 10 between the indoor unit 2 and the relay unit 17. At the refrigerant pipe 10 extending from the indoor-unit-side shut-off valve 30a-1, check valves 21a and 21b are provided. At the refrigerant pipe 10 extending from the indoor-unit-side shut-off valve 30a-3, check valves 21c and 21d are provided. At the refrigerant pipe 10 extending from the indoor-unit-side shut-off valve 30a-5, check valves 21e and 21f are provided. The indoor-unit-side shut-off valve 30a is located closer to an associated one of the indoor units 2 than to the relay unit 17. Accordingly, the indoor-unit-side shut-off valve 30a-1 and the indoor-unit-side shut-off valve 30a-2 are located closer to the indoor unit 2a than to the relay unit 17. The indoor-unit-side shut-off valve 30a-3 and the indoor-unit-side shut-off valve 30a-4 are located closer to the indoor unit 2b than to the relay unit 17. The indoor-unit-side shut-off valve 30a-5 and the indoor-unit-side shut-off valve 30a-6 are located closer to the indoor unit 2c than to the relay unit 17.
As illustrated in
The indoor-unit-side shut-off valves 30a-1 to 30a-6 and the indoor units 2a to 2c are the same in configuration as those according to Embodiment 1, and their descriptions will thus be omitted. Although the indoor units 2b and 2c each include the indoor heat exchanger 4 and the expansion valve 5 as well as the indoor unit 2a, illustration of the indoor heat exchangers 4 and the expansion valves 5 of the indoor units 2b and 2c is thus omitted in
The relay unit 17 includes a gas-liquid separator 18, heat exchangers 23a and 23b, expansion valves 19a and 19b, the check valves 21a, 21b, 21c, 21d, 21e, and 21f, the on-off valves 22a, 22b, 22c, 22d, 22e, and 22f, and pipes 24a, 24b, 24c, and 24d. As illustrated in
The flow of the refrigerant in the cooling main operation will be described below. With reference to the solid arrows in
The refrigerant is compressed in the compressor 6 to change into gas refrigerant, and the gas refrigerant passes through the refrigerant flow switching device 9 and flows into the outdoor heat exchanger 7. The gas refrigerant that has flowed into the outdoor heat exchanger 7 exchanges heat with outdoor air to condense while transferring heat to the outdoor air, thereby changing into two-phase gas-liquid refrigerant. The two-phase gas-liquid refrigerant then flows out from the outdoor heat exchanger 7.
The two-phase gas-liquid refrigerant that has flowed out form the outdoor heat exchanger 7 passes through the expansion valve 8 and the check valve 16a, and then flows out from the outdoor unit 3. The two-phase gas-liquid refrigerant that has flowed out from the outdoor unit 3 passes through the refrigerant-pipe communication part 10a and the outdoor-unit-side shut-off valve 30b-1 and flows into the relay unit 17. The two-phase gas-liquid refrigerant that has flowed into the relay unit 17 flows into the gas-liquid separator 18, and is separated into gas refrigerant and liquid refrigerant. The gas refrigerant flows into the pipe 24a, and the liquid refrigerant flows into the pipe 24b. With the pipe 24a into which the gas refrigerant flows, the on-off valves 22b, 22d, and 22f are connected. With the pipe 24b to which the liquid refrigerant flows, the heat exchanger 23b, the expansion valve 19a, the heat exchanger 23a, and the check valves 21b, 21d, and 21f are connected.
The gas refrigerant that has flowed into the pipe 24a flows toward the indoor unit 2c which performs the heating operation. To be more specific, the gas refrigerant that has flowed into the pipe 24a passes through the on-off valve 22f and through the indoor-unit-side shut-off valve 30a-6 associated with the indoor unit 2c, and then flows into the indoor unit 2c. The gas refrigerant that has flowed into the indoor unit 2c flows into the indoor heat exchanger 4.
The gas refrigerant that has flowed into the indoor heat exchanger 4 of the indoor unit 2c exchanges heat with indoor air to condense while transferring heat to the indoor air, thereby heating the indoor air. As a result, the gas refrigerant changes into liquid refrigerant, and the liquid refrigerant flows out from the indoor heat exchanger 4. The liquid refrigerant that has flowed out from the indoor heat exchanger 4 is reduced in pressure by the expansion valve 5, and then flows out from the indoor unit 2c. The liquid refrigerant that has flowed out from the indoor unit 2c passes through the indoor-unit-side shut-off valve 30a-5 and flows into the relay unit 17.
The liquid refrigerant that has flowed into the relay unit 17 passes through the check valve 21e and flows into the pipe 24d. The pipe 24d is connected to the pipe 24b located close to the outlet of the expansion valve 19a. Therefore, in the pipe 24b, the liquid refrigerant that has flowed into the pipe 24d joins the liquid refrigerant that has been subjected to separation by the gas-liquid separator 18 and then expanded by the expansion valve 19a.
The liquid refrigerant that has been obtained through separation by the gas-liquid separator 18 and flowed into the pipe 24b flows through the heat exchanger 23b and the expansion valve 19a, and as a result, is subcooled. The subcooled liquid refrigerant joins the liquid refrigerant flowing from the pipe 24d. The liquid refrigerant obtained by the above joining is further subcooled in the heat exchanger 23a, and then branches off. Branching part of the refrigerant flows from the pipe 24b into the pipe 24c. Remaining part of the liquid refrigerant that has not flowed into the pipe 24c flows through the pipe 24b and flows toward one of the indoor unit 2a and the indoor unit 2b that performs the cooling operation.
The pipe 24c is connected with the expansion valve 19b and the heat exchangers 23a and 23b. The pipe 24c is connected with a pipe 24e at a location close to the outlet of the heat exchanger 23b. Thus, the above branching part of the liquid refrigerant that has flowed into the pipe 24c after flowing out from the heat exchanger 23a is reduced in pressure in the expansion valve 19b, and then flows through the heat exchangers 23a and 23b. In the heat exchangers 23a and 23b, the liquid refrigerant exchanges heat with the liquid refrigerant flowing in the pipe 24b to receive heat therefrom, thereby subcooling the liquid refrigerant flowing in the pipe 24b. After flowing out from the heat exchanger 23b, the refrigerant joins the gas refrigerant flowing in the pipe 24e. The refrigerant obtained through the above joining then flows through the outdoor-unit-side shut-off valve 30b-2 and the refrigerant-pipe communication part 10b, and flows into the outdoor unit 3.
The above remaining part of the liquid refrigerant that has not flowed into the pipe 24c after flowing out from the heat exchanger 23a flows through the check valve 21b or the check valve 21d, then flows through the indoor-unit-side shut-off valve 30a-1 associated with the indoor unit 2a or through the indoor-unit-side shut-off valve 30a-3 associated with the indoor unit 2b, and flows into the indoor unit 2a or the indoor unit 2b. The liquid refrigerant that has flowed into the indoor unit 2a or the indoor unit 2b is reduced in pressure by the expansion valve 5, and then flows into the indoor heat exchanger 4. The liquid refrigerant that has flowed into the indoor heat exchanger 4 exchanges heat with indoor air to receive heat therefrom and evaporate, thereby cooling the indoor air. As a result, the liquid refrigerant changes into gas refrigerant, and the gas refrigerant flows out from the indoor heat exchanger 4.
The gas refrigerant that has flowed out from the indoor heat exchanger 4 flows through the indoor-unit-side shut-off valve 30a-2 or the indoor-unit-side shut-off valve 30a-4 and flows into the relay unit 17. The gas refrigerant that has flowed into the relay unit 17 flows through the on-off valve 22a or the on-off valve 22c and flows into the pipe 24e. The gas refrigerant that has flowed into the pipe 24e joins the refrigerant flowing in the pipe 24c, and the refrigerant obtained through the joining then flows through the outdoor-unit-side shut-off valve 30b-2 and the refrigerant-pipe communication part 10b and flows into the outdoor unit 3.
The gas refrigerant that has flowed from the relay unit 17 into the outdoor unit 3 through the outdoor-unit-side shut-off valve 30b-2 flows through the check valve 16d, the refrigerant flow switching device 9, and the accumulator 25, and returns to the compressor 6. In the cooling main operation, the above circulation of the refrigerant is repeated.
The flow of the refrigerant in the heating main operation will be described below. With reference to the dashed arrows in
Refrigerant compressed in the compressor 6 flows through the refrigerant flow switching device 9 and the check valve 16b, flows out from the outdoor unit 3, then flows through the refrigerant-pipe communication part 10a and the outdoor-unit-side shut-off valve 30b-1, and flows into the relay unit 17. The refrigerant that has flowed into the relay unit 17 flows into the gas-liquid separator 18 and is separated into gas refrigerant and liquid refrigerant. The gas refrigerant flows into the pipe 24a, and the liquid refrigerant flows into the pipe 24b.
The gas refrigerant that has flowed into the pipe 24a flows toward one of the indoor unit 2a and the indoor unit 2b that performs the heating operation. More specifically, the gas refrigerant that has flowed into the pipe 24a passes through the on-off valve 22b or the on-off valve 22d, then flows through the indoor-unit-side shut-off valve 30a-2 associated with the indoor unit 2a or through the indoor-unit-side shut-off valve 30a-4 associated with the indoor unit 2b, and flows into the indoor unit 2a or the indoor unit 2b. The gas refrigerant that has flowed into the indoor unit 2a or the indoor unit 2b flows into the indoor heat exchanger 4.
The gas refrigerant that has flowed into the indoor heat exchanger 4 of the indoor unit 2a or the indoor unit 2b exchanges heat with indoor air to condense while transferring heat to the indoor air, thereby heating the indoor air. As a result, the gas refrigerant changes into liquid refrigerant, and the liquid refrigerant flows out from the indoor heat exchanger 4. The liquid refrigerant that has flowed out from the indoor heat exchanger 4 is reduced in pressure by the expansion valve 5 of the indoor unit 2a or the indoor unit 2b, and then flows out from the indoor unit 2a or the indoor unit 2b. The liquid refrigerant that has flowed out from the indoor unit 2a or the indoor unit 2b flows through the indoor-unit-side shut-off valve 30a-1 or the indoor-unit-side shut-off valve 30a-3 and flows into the relay unit 17.
The liquid refrigerant that has flowed into the relay unit 17 flows through the check valve 21a or the check valve 21c and flows into the pipe 24d. The pipe 24d is connected to the pipe 24b, and the liquid refrigerant that has flowed into the pipe 24d thus joins, in the pipe 24b, the liquid refrigerant that has been obtained through separation by the gas-liquid separator 18 and expanded by the expansion valve 19a.
The liquid refrigerant flowing from the pipe 24d joins the liquid refrigerant that has flowed into the pipe 24b after being obtained through the separation by the gas-liquid separator 18. The liquid refrigerant obtained through the separation by the gas-liquid separator 18 flows through the heat exchanger 23b and the expansion valve 19a and is subcooled. The subcooled liquid refrigerant joins the liquid refrigerant flowing from the pipe 24d. The liquid refrigerant obtained through the above joining is further subcooled in the heat exchanger 23a, and branches off. Then, branching part of the liquid refrigerant flows from the pipe 24b into the pipe 24c. The pipe 24c is connected to the pipe 24e, and the above branching part of the liquid refrigerant that has flowed into the pipe 24c passes through the expansion valve 19b and the heat exchangers 23a and 23b and then flows into the pipe 24e. The refrigerant that has flowed into the pipe 24e passes through the outdoor-unit-side shut-off valve 30b-2 and the refrigerant-pipe communication part 10b and flows into the outdoor unit 3.
Remaining part of the liquid refrigerant that has not flowed into the pipe 24c flows through the pipe 24b and flows toward the indoor unit 2c, which performs the cooling operation. Specifically, the above remaining part of the liquid refrigerant that has not flowed into the pipe 24c passes through the check valve 21f, then passes through the indoor-unit-side shut-off valve 30a-5 associated with the indoor unit 2c, and flows into the indoor unit 2c. The liquid refrigerant that has flowed into the indoor unit 2c is reduced in pressure by the expansion valve 5 and then flows into the indoor heat exchanger 4. The liquid refrigerant that has flowed into the indoor heat exchanger 4 exchanges heat with indoor air to receive heat therefrom and evaporate, thereby cooling the indoor air. As a result, the liquid refrigerant changes into gas refrigerant, and the gas refrigerant flows out from the indoor heat exchanger 4.
The gas refrigerant that has flowed out form the indoor heat exchanger 4 flows out from the indoor unit 2c, passes through the indoor-unit-side shut-off valve 30a-6, and flows into the relay unit 17. The gas refrigerant that has flowed into the relay unit 17 passes through the on-off valve 22e and flows into the pipe 24e. The gas refrigerant that has flowed into the pipe 24e joins the refrigerant flowing in the pipe 24c, then passes through the outdoor-unit-side shut-off valve 30b-2 and the refrigerant-pipe communication part 10b, and flows into the outdoor unit 3.
The gas refrigerant that has flowed from the relay unit 17 into the outdoor unit 3 through the outdoor-unit-side shut-off valve 32b-2 passes through the check valve 16c, the expansion valve 8, and the outdoor heat exchanger 7, and is completely gasified. The completely gasified refrigerant returns to the compressor 6 through the refrigerant flow switching device 9 and the accumulator 25. In the heating main operation, the above circulation of the refrigerant is repeated.
When it is detected that a refrigerant leak occurs, each of the shut-off valves 30 is closed as described above regarding Embodiment 1. As a result, the region where each indoor unit 2 is located, the region where the relay unit 17 is located, and the region where the outdoor unit 3 is located are isolated from each other as independent regions. In this state, as described above regarding Embodiment 1, external equipment such as a pressure sensor or a vacuum pump is connected to the shut-off valve 30, whereby it is possible to determine the location at which the refrigerant leak occurs, and perform maintenance. For example, in the case where a refrigerant leak occurs in the vicinity of the check valve 21a that is provided as illustrated in
Furthermore, in the case of drawing the refrigerant from the relay unit 17 in order to prevent an increase in the amount of refrigerant leak, devices for drawing refrigerant are connected to respective indoor-unit side shut-off valves, that is, the indoor-unit-side shut-off valves 30a-1 to 30a-6, to draw back the refrigerant. By applying this way, it is possible to reduce the amount of time required to draw back the refrigerant. Furthermore, in the case of evacuating the refrigerant pipes 10 after repairing an area where the refrigerant leak occurs, vacuum pumps are connected to plural shut-off valves 30. Thus, they can be evacuated at the same time. It is therefore possible to reduce the time that is required for maintenance from the time at which refrigerant leaks from the air-conditioning apparatus 100.
As described above, in Embodiment 2, the plural indoor units 2 is provided; the relay unit 17 is installed between the outdoor unit 3 and the indoor units 2a to 2c, and switches the flow passage to be used in the refrigerant circuit between plural flow passages; the outdoor unit 3, the relay unit 17, and the indoor units 2a to 2c are connected by the refrigerant pipes 10; and for the indoor units 2a to 2c, the respective indoor-unit-side shut-off valves 30a are provided, and each of the indoor-unit-side shut-off valves 30a is located closer to an associated one of the indoor units 2 than to the relay unit 17.
By virtue of the above configuration, the inside of the air-conditioning apparatus 100 is divided into a region where the outdoor unit 3 is installed, a region located between the relay unit 17 and the indoor unit 2, a region where the indoor unit 2a is installed, a region where the indoor unit 2b is installed, and a region where the indoor unit 2c is installed, whereby those regions can be subjected to maintenance independently of each other. It is therefore possible to perform maintenance on the above regions simultaneously, and thus reduce the time required for maintenance on the air-conditioning apparatus 100. Accordingly, the maintainability of the air-conditioning apparatus 100 is improved.
In existing air-conditioning apparatuses having a relay unit, the total length of refrigerant pipes is great, and the amount of refrigerant to be used is large. Thus, in some cases, it takes time to perform maintenance such as an operation to determine the location at which a refrigerant leak occurs, an operation to draw back refrigerant, an operation to re-fill refrigerant, and an operation to evacuate the refrigerant pipes. In the air-conditioning apparatus 100 according to Embodiment 2, refrigerant pipes 10 branch off in a complicated way in regions located between the relay unit 17 and the indoor units 2, and the total length of the refrigerant pipes 10 is great. However, in the air-conditioning apparatus 100 according to Embodiment 2, external equipment is connected to the service ports 50 of the indoor-unit-side shut-off valves 30a-1 to 30a-6, whereby maintenance can be performed simultaneously on the regions located between the relay unit 17 and the indoor units 2. Therefore, the maintainability of the air-conditioning apparatus 100 is further improved.
The shut-off valves 30 and the air-conditioning apparatus 100 according to Embodiment 3 will be described below. In the air-conditioning apparatus 100 according to Embodiment 3, plural relay units 17 are provided between the outdoor unit 3 and the plural indoor units 2, and the shut-off valves 30 include relay-unit-side shut-off valves 30c. In this regard, the air-conditioning apparatus 100 of Embodiment 3 is different in configuration from the air-conditioning apparatus 100 of Embodiment 1. Regarding Embodiment 3, components that are the same as those in Embodiment 1 and/or Embodiment 2 will be denoted by the same reference signs, and their descriptions will thus be omitted.
Outdoor-unit-side shut-off valves 30b-1, 30b-2, and 30b-3 are provided between the outdoor unit 3 and the relay units 17a and 17b. The outdoor-unit-side shut-off valve 30b-1 is provided at the refrigerant-pipe communication part 10a. The outdoor-unit-side shut-off valve 30b-2 is provided at the refrigerant-pipe communication part 10b. The outdoor-unit-side shut-off valve 30b-3 is provided at the refrigerant-pipe communication part 10c. The outdoor-unit-side shut-off valves 30b-1 to 30b-3 are located closer to the outdoor unit 3 than to the relay unit 17.
The relay-unit-side shut-off valves 30c are provided between the outdoor unit 3 and the relay units 17a and 17b. The relay-unit-side shut-off valves 30c, as well as the indoor-unit-side shut-off valves 30a and the outdoor-unit-side shut-off valves 30b, are similar in configuration to the shut-off valves 30 according to Embodiment 1. In other words, the shut-off valves 30 include the relay-unit-side shut-off valves 30c. As illustrated in
The relay-unit-side shut-off valves 30c-1, 30c-2, and 30c-3 are associated with the relay unit 17a. The relay-unit-side shut-off valves 30c-4, 30c-5, and 30c-6 are associated with the relay unit 17b. The relay-unit-side shut-off valve 30c are each provided at the refrigerant pipe 10 connecting the outdoor unit 3 and the relay unit 17, at a location close to an associated one of the relay units 17. That is, the relay-unit-side shut-off valves 30c-1 to 30c-3 are located closer to the relay unit 17a than to the outdoor unit 3. The relay-unit-side shut-off valves 30c-4 to 30c-6 are located closer to the relay unit 17b than to the outdoor unit 3.
As illustrated in
The indoor units 2a and 2b are connected to the relay unit 17a. The indoor units 2c and 2d are connected to the relay unit 17b. The refrigerant pipe 10 between the indoor unit 2a and the relay unit 17a is provided with the indoor-unit-side shut-off valves 30a-1 and 30a-2. At refrigerant pipes 10 between the indoor unit 2b and the relay unit 17a, the indoor-unit-side shut-off valves 30a-3 and 30a-4 are provided. At refrigerant pipes 10 between the indoor unit 2c and the relay unit 17b, the indoor-unit-side shut-off valves 30a-5 and 30a-6 are provided. At the refrigerant pipes 10 between the indoor unit 2d and the relay unit 17b, the indoor-unit-side shut-off valves 30a-7 and 30a-8 are provided. The configurations of the shut-off valves 30 according to Embodiment 3 are the same as those according to Embodiment 1, and their descriptions will thus be omitted.
When it is detected that a refrigerant leak occurs, as described regarding Embodiment 1, the shut-off valves 30 are closed. The air-conditioning apparatus 100 according to Embodiment 3 includes the relay-unit-side shut-off valves 30c. As a result, regions where the respective indoor units 2 are installed, regions where the respective relay units 17 are installed, regions located between the relay units 17 and the outdoor unit 3, and a region where the outdoor unit 3 is located are isolated from each other as independent regions. For example, in the case where refrigerant leaks from the refrigerant-pipe communication part 10a, a detection value obtained by a pressure sensor connected to any one of the outdoor-unit-side shut-off valve 30b-1, the relay-unit-side shut-off valve 30c-1, and the relay-unit-side shut-off valve 30c-4 can be considered to be close to the atmospheric pressure. Therefore, it is possible to shorten the time required for checking to determine part of the refrigerant pipe 10 where the refrigerant leak occurs, by starting the checking from an area close to the shut-off valve 30 connected to the pressure sensor that obtains the detection value close to the atmospheric pressure. It is therefore possible to reduce the time required for the checking.
In the case of drawing back refrigerant from the refrigerant-pipe communication part 10a in order to prevent an increase in the amount of refrigerant leak, the device for drawing refrigerant connected to each of the outdoor-unit-side shut-off valve 30b-1, the relay-unit-side shut-off valve 30c-1, and the relay-unit-side shut-off valve 30c-4 to draw back refrigerant. By applying this way, it is possible to shorten the time required to draw back refrigerant. Furthermore, in the case of evacuating the refrigerant-pipe communication part 10a after repairing an area where a refrigerant leak occurs, vacuum pumps are connected to the outdoor-unit-side shut-off valve 30b-1, the relay-unit-side shut-off valve 30c-1, and the relay-unit-side shut-off valve 30c-4 to enable simultaneous evacuation to be performed. It is therefore possible to reduce the time required for maintenance that is performed after refrigerant leaks from the air-conditioning apparatus 100. Therefore, the maintainability of the air-conditioning apparatus 100 can be further improved.
As described above, the shut-off valves 30 according to Embodiment 3 include the plural indoor-unit-side shut-off valves 30a, the plural outdoor-unit-side shut-off valves 30b, and plural relay-unit-side shut-off valves 30c. It is therefore possible to divide the inside of the air-conditioning apparatus 100 according to Embodiment 3 into a region where the indoor unit 2a is installed, a region where the indoor unit 2b is installed, a region where the indoor unit 2c is installed, a region where the indoor unit 2d is installed, a region where the relay unit 17a is installed, a region where the relay unit 17b is installed, and a region located between the outdoor unit 3 and the relay unit 17. Furthermore, each of the above regions can be subjected to maintenance as an independent region. In existing air-conditioning apparatuses including a relay unit, since the total length of refrigerant pipes is great and the amount of refrigerant to be used is large, in some cases, it takes time to perform maintenance such as an operation to determine the location where a refrigerant leak occurs, an operation to draw back an operation to re-fill refrigerant, and an operation to evacuate refrigerant pipes. In contrast, in the air-conditioning apparatus 100 according to Embodiment 3, it is possible to perform maintenance simultaneously on plural regions as independent regions. It is therefore possible to further improve the maintainability of the air-conditioning apparatus.
This application is a U.S. national stage application of PCT/JP2021/046919 filed on Dec. 20, 2021, the contents of which are incorporated herein by reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2021/046919 | 12/20/2021 | WO |
