How to open and close the shutoff valve kit

Abstract

To provide a shut-off kit securing safety when refrigerant leaks, and also performing work such as confirmation of airtightness and evacuation.SOLUTION: A shut-off valve kit includes: a first refrigerant piping 51 connecting a gas refrigerant piping 30 on the side of an outdoor unit 10 and a gas refrigerant piping 30 on the side of an indoor unit 20; a second refrigerant piping 52 connecting a liquid refrigerant piping 31 on the side of the outdoor unit 10 and a liquid refrigerant piping 31 on the side of the indoor unit 20; a gas-side opening / closing valve 42 mounted on the first refrigerant piping 51; a liquid-side opening / closing valve 41 mounted on the second refrigerant piping 52; a by-pass piping 43 connecting the second refrigerant piping 52 on the side of the indoor unit 20 and the second refrigerant piping 52 on the side of the outdoor unit 10; and a by-pass opening / closing valve 44 mounted on the by-pass piping 43. The gas-side opening / closing valve 42 and the liquid-side opening / closing valve 41 are composed of normal closed type electromagnetic valves. The by-pass opening / closing valve 44 comprises a motor valve or a manual valve. The by-pass opening / closing valve 44 is opened in an airtight test and in evacuation.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a shutoff valve kit, an air conditioner, and an indoor unit. [Background technology]

[0002] In recent years, there has been a trend toward using slightly flammable refrigerants such as R32 or flammable refrigerants in air conditioners. If such a slightly flammable or flammable refrigerant leaks, it is necessary to detect the refrigerant leak and stop the supply of refrigerant to the indoor unit before the refrigerant concentration in the conditioned space or the indoor unit installation space reaches the lower flammability limit (LFL). For this reason, for example, a shutoff valve may be provided in a refrigerant pipe that sends refrigerant to the indoor unit.

[0003] A conventional technology has been disclosed in which a refrigeration cycle is formed by connecting a compressor, a first heat exchanger, a first electric expansion valve, a second electric expansion valve, and a second heat exchanger in sequence with piping for circulating a refrigerant, and which is provided with an expansion valve closing mechanism that closes the first and second electric expansion valves when the power supply from the power supply source is cut off, the expansion valve closing mechanism having a battery that serves as an auxiliary power source and cut-off detection means that detects the cut-off of the power supply from the power supply source, and when the cut-off detection means detects the cut-off of the power supply from the power supply source, the first and second electric expansion valves are closed by the power supplied from the battery (see, for example, Patent Document 1). As a result, even during a power outage, the first and second electric expansion valves can be closed using power from the battery to stop refrigerant leakage, thereby improving safety. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-121333 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present disclosure is to provide a shutoff valve kit, an air conditioner, and an indoor unit that ensure safety in the event of a refrigerant leak and that allow tasks such as checking airtightness and vacuuming to be performed. [Means for solving the problem]

[0006] In order to achieve the above object, the method for opening and closing a shutoff valve kit of the present disclosure includes: a first refrigerant pipe connecting a gas refrigerant pipe on an outdoor unit side and the gas refrigerant pipe on an indoor unit side; a second refrigerant pipe connecting a liquid refrigerant pipe on the outdoor unit side and the liquid refrigerant pipe on the indoor unit side; a gas side on-off valve provided on the first refrigerant pipe; a liquid side on-off valve provided on the second refrigerant pipe; a bypass pipe connecting the first refrigerant pipe on the outdoor unit side and the second refrigerant pipe on the indoor unit side or connecting the first refrigerant pipe on the indoor unit side and the second refrigerant pipe on the outdoor unit side; and a bypass on-off valve provided on the bypass pipe, wherein the gas side on-off valve and the liquid side on-off valve are normally closed type solenoid valves, and the bypass on-off valve is an electrically operated valve or a manual valve, and the shut-off valve kit is installed in an open state, wherein the bypass on-off valve is opened during an airtightness test and when drawing a vacuum, . [Effects of the Invention]

[0007] According to the present disclosure, safety can be ensured in the event of a refrigerant leak, and tasks such as checking airtightness and vacuuming can be easily performed. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram showing an air conditioning apparatus according to a first embodiment of the present invention; [Figure 2] 1 is a flowchart showing the flow from installation to start of operation of the air conditioning apparatus 1 of the first embodiment. [Figure 3] Schematic configuration diagram showing an air conditioning apparatus according to a second embodiment [Figure 4] Schematic configuration diagram showing an air conditioning apparatus according to a third embodiment [Figure 5] Schematic configuration diagram showing an air conditioning apparatus according to a fourth embodiment [Figure 6] 10 is a schematic diagram showing an air conditioning apparatus according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] (Findings that formed the basis of this disclosure) At the time the inventors came up with the idea for the present disclosure, there was a technology in existence that included a cutoff detection means for detecting a cutoff of the power supply from the commercial power source, and when the cutoff detection means detected a cutoff of the power supply from the commercial power source, the technology was configured to close the refrigerant cutoff valve using external power from a battery or the like. Furthermore, when installing an air conditioner, the outdoor unit and indoor unit are installed, and refrigerant piping work is performed to connect the refrigerant piping. After the refrigerant piping work is completed, the airtightness of the refrigerant piping is checked, and once the airtightness of the refrigerant piping has been confirmed, the refrigerant piping is typically vacuumed.

[0010] However, when refrigerant piping work is usually completed, power supply work has not yet been completed. Therefore, if the refrigerant shutoff valve is a normally closed solenoid valve that closes when power is not supplied, the refrigerant shutoff valve cannot be opened before the commercial power supply is turned on, and the refrigerant piping connecting the outdoor unit and the indoor unit is cut off. This creates the problem of not being able to check the airtightness or perform the vacuuming work described above. By providing an external power supply for power supply, a normally closed solenoid valve can be placed in the open state even before the commercial power supply is turned on. However, since airtightness testing and vacuuming generally take more than an hour, an external power supply with a large power capacity must be provided, which increases the equipment cost. The inventors discovered this problem and have come up with the subject matter of the present disclosure to solve this problem.

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters or redundant descriptions of substantially identical configurations may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art. The accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0012] (Embodiment 1) Hereinafter, the first embodiment will be described with reference to FIG. FIG. 1 is a schematic configuration diagram showing a first embodiment of an air conditioner according to the present invention.

[0013] [1-1.Configuration] [1-1-1. Air Conditioning Equipment Configuration] As shown in FIG. 1, the air conditioning apparatus 1 of this embodiment includes an outdoor unit 10, an indoor unit 20, a gas refrigerant pipe 30, a liquid refrigerant pipe 31, a shutoff valve kit 40, and a control unit (not shown). The outdoor unit 10 houses a compressor 11, a four-way valve 12 that switches the refrigerant flow path, an outdoor heat exchanger 13, and an outdoor throttling device 14, and these compressor 11, four-way valve 12, outdoor heat exchanger 13, and outdoor throttling device 14 are connected in sequence by refrigerant piping 15. The indoor unit 20 houses an indoor heat exchanger 21, an indoor throttling device 22, and an indoor blower 23, and the indoor heat exchanger 21 and the indoor throttling device 22 are connected via a refrigerant pipe 24.

[0014] The compressor 11 of the outdoor unit 10 and the indoor heat exchanger 21 of the indoor unit 20 are connected by a gas refrigerant pipe 30 and a liquid refrigerant pipe 31 . A service valve 32 is provided at the location where the outdoor unit 10 is connected to the gas refrigerant pipe 30 and the liquid refrigerant pipe 31 , and the service valve 32 has a service port 33 . Furthermore, an on-off valve 34 is provided at the point where the indoor unit 20 is connected to the gas refrigerant pipe 30 and the liquid refrigerant pipe 31.

[0015] A shutoff valve kit 40 is provided midway through the liquid refrigerant pipe 31 and the gas refrigerant pipe 30 that connect the outdoor unit 10 and the indoor unit 20.

[0016] [1-1-2. On-off valve] On-off valves are broadly divided into solenoid valves and motor-operated valves. A solenoid valve is a valve in which a valve called a drive plunger is biased by a spring, and when an electric current is passed through an electromagnet (solenoid), the valve moves back and forth using electromagnetic force.Solenoid valves are further classified into normally closed type solenoid valves, which are open when energized and closed when de-energized, and normally open type solenoid valves, which are closed when energized and open when de-energized. On the other hand, motor-operated valves, like ball valves, are valves that control the opening and closing of a flow path by rotating a valve element. Unlike solenoid valves, motor-operated valves can be opened or closed when not energized.

[0017] [1-1-3.Shut-off Valve Kit 40] In this embodiment, the shutoff valve kit 40 includes a first refrigerant pipe 51 connected to the gas refrigerant pipe 30 and a second refrigerant pipe 52 connected to the liquid refrigerant pipe 31. A liquid-side on-off valve 41 is provided midway through the second refrigerant pipe 52. The liquid-side on-off valve 41 is configured as a normally closed solenoid valve. Because the pipe diameters of the liquid refrigerant pipe 31 and the second refrigerant pipe 52 are small, a direct-acting valve or the like is used as the liquid-side on-off valve 41 as a solenoid valve. A direct-acting valve is a valve that opens and closes using only the electromagnetic force of a coil. When a direct-acting valve is used as the liquid-side on-off valve 41, even when the liquid-side on-off valve 41 is closed, if there is a large pressure difference from the indoor unit 20 side to the outdoor unit 10 side, the refrigerant will pass through the liquid-side on-off valve 41 and flow from the indoor unit 20 side to the outdoor unit 10 side.

[0018] A gas side on-off valve 42 is provided midway through the first refrigerant piping 51. Like the liquid side on-off valve 41, the gas side on-off valve 42 is also configured as a normally closed solenoid valve. Because the gas refrigerant piping 30 and the first refrigerant piping 51 have larger piping diameters than the liquid side refrigerant piping 31, a pilot-type valve, for example, is used as the gas side on-off valve 42. A pilot-type valve is configured to open a valve element using the electromagnetic force of a coil and a pressure difference in the refrigerant piping. Therefore, when a pilot-type valve is used as the gas side on-off valve 42, even if the pressure difference from the indoor unit 20 side to the outdoor unit 10 side is large, as long as the gas side on-off valve 42 is closed, the refrigerant will not pass through the gas side on-off valve 42 from the indoor unit 20 side to the outdoor unit 10 side.

[0019] In addition, a bypass pipe 43 is provided that connects a second refrigerant pipe 52 on the outdoor unit 10 side of the liquid side on-off valve 41 with a first refrigerant pipe 51 of the indoor unit 20 on the gas side on-off valve 42. A bypass on-off valve 44 is provided in the middle of the bypass pipe 43. The bypass on-off valve 44 is configured as an electric valve. In addition, the bypass piping 43 may connect the second refrigerant piping 52 on the indoor unit 20 side of the liquid side on-off valve 41 to the first refrigerant piping 51 of the outdoor unit 10 on the gas side on-off valve 42. The first refrigerant piping 51 is provided with a gas side bypass piping 45 that bypasses the first refrigerant piping 51 on the outdoor unit 10 side of the liquid side on-off valve 42 and the first refrigerant piping 51 on the indoor unit 20 side of the liquid side on-off valve 42. A check valve 46 is provided in the middle of the gas side bypass piping 45. The check valve 46 is configured so that the refrigerant flows only from the indoor unit 20 side to the outdoor unit 10 side.

[0020] [1-2. Operation / effect] Next, the operation and function of this embodiment will be described with reference to FIG. FIG. 2 is a flowchart showing the flow from installation of the air conditioner 1 to the start of operation. First, after the outdoor unit 10 and the indoor unit 20 are installed in a predetermined location, refrigerant piping work is performed to connect the refrigerant piping via the shutoff valve kit 40 (ST1). At this time, the shutoff valve kit 40 is installed with the bypass on-off valve 44 open.

[0021] Once the refrigerant piping work is completed, an airtight test is performed on the gas refrigerant piping 30 and the liquid refrigerant piping 31 (ST2). This airtight test is performed by filling nitrogen gas into the refrigerant piping through the service port 33 of the service valve 32 and checking for leaks from the refrigerant piping. As described above, when an airtightness test is performed, the bypass on-off valve 44 is in an open state.

[0022] As a result, nitrogen gas introduced from the service port 33 of the liquid refrigerant piping 31 passes through the liquid refrigerant piping 31 and the second refrigerant piping 52 and is introduced to the liquid side on-off valve 41. In addition, nitrogen gas sent to the second refrigerant piping 52 is introduced into the bypass piping 43 along the way, and then passes through the first refrigerant piping 51, the gas refrigerant piping 30 between the shutoff valve kit 40 and the indoor unit 20, the indoor unit 20, the liquid refrigerant piping 31 between the shutoff valve kit 40 and the indoor unit 20, and the second refrigerant piping 52 in this order, before being introduced to the liquid side on-off valve 41. On the other hand, nitrogen gas introduced from the service port 33 of the gas refrigerant pipe 30 flows through the first refrigerant pipe 51 and is introduced up to the liquid side on-off valve 42.

[0023] As described above, in this embodiment, the liquid side on-off valve 41 and the gas side on-off valve 42 are normally closed type solenoid valves, and therefore, generally, during an airtightness test when the commercial power supply is not energized, the gas side on-off valve 41 and the liquid side on-off valve 42 are in a closed state. However, by providing a bypass piping 43 having a bypass on-off valve 44 in an open state, it is possible to properly perform an airtightness test of the refrigerant piping.

[0024] After the airtightness test is completed, the insides of the gas refrigerant pipe 30 and the liquid refrigerant pipe 31 are evacuated (ST3). Vacuuming is the process of drawing air from the service port 33 of the gas refrigerant pipe 30 and the service port 33 of the liquid refrigerant pipe 31 to create a vacuum inside the gas refrigerant pipe 30 and the liquid refrigerant pipe 31. Because a direct acting normally closed solenoid valve is used as the liquid side on-off valve 41, even when the liquid side on-off valve 41 is closed, if there is a large pressure difference from the indoor unit 20 side to the outdoor unit 10 side, the refrigerant passes through the liquid side on-off valve 41 and flows from the indoor unit 20 side to the outdoor unit 10 side. This allows air to be sucked from the liquid refrigerant piping 31 and the second refrigerant piping 52. In addition, a bypass pipe 43 is provided. As a result, the refrigerant in the first refrigerant pipe 51 on the indoor unit 20 side of the liquid side on-off valve 42 and the gas refrigerant pipe 30 between the shutoff valve kit 40 and the indoor unit 20 can be sucked into the second refrigerant pipe 52 on the outdoor unit 10 side of the liquid side on-off valve 41 via the bypass pipe 43.

[0025] Furthermore, a check valve 46 is provided in gas-side bypass piping 45 that bypasses the gas-side on-off valve 42 of the gas refrigerant piping 30, and a pilot-type normally closed solenoid valve is used as the gas-side on-off valve 42. During evacuation, the gas-side on-off valve 42 is closed, so the air in the first refrigerant piping 51 does not pass through the gas-side on-off valve 42 from the indoor unit 20 side to the outdoor unit 10 side, but the air in the first refrigerant piping 51 can be sucked from the indoor unit 20 side to the outdoor unit 10 side via the gas-side bypass piping 45. This allows for more efficient evacuation.

[0026] After the gas refrigerant pipe 30 and the liquid refrigerant pipe 31 have been evacuated, a refrigerant charging process is performed (ST4), in which refrigerant is charged into the refrigerant pipes via the service port 33. Even in this refrigerant charging process, the bypass on-off valve 44 is open, so the second refrigerant pipe 52 and the first refrigerant pipe 51 are connected to each other, and the refrigerant can be charged throughout the entire gas refrigerant pipe 30, the first refrigerant pipe 51, the liquid refrigerant pipe 31, and the second refrigerant pipe 52. Then, after the refrigerant charging process, power supply work is performed (ST5), and the control unit controls the bypass on-off valve 44, which is an electrically operated valve, to a closed state (ST6). After that, the control unit controls the air conditioner 1 to perform a predetermined test run (ST7). After the test run is completed, normal operation such as cooling operation or heating operation is performed (ST8).

[0027] In this way, the shutoff valve kit 40 is installed with the bypass on-off valve 44 open, so that the subsequent airtightness test, evacuation, and refrigerant charging processes can be carried out properly. Furthermore, after the power supply work is completed, the bypass on-off valve 44 is closed by the control unit, so that a trial run can be carried out. Furthermore, from the installation of the air conditioner 1 to the trial run, the bypass on-off valve 44 only needs to be controlled to open and close once, so installation, airtightness testing, evacuation, and trial run can be easily carried out.

[0028] Furthermore, when an instruction is given to start a pump-down operation to recover the refrigerant in the outdoor heat exchanger 13 of the air conditioner 1, or a refrigerant recovery operation to recover the refrigerant in a refrigerant recovery vessel, the control unit controls the bypass on-off valve 44 to an open state. When a building is demolished, the air conditioner may be removed without being energized to the commercial power source. In this case, the liquid side on-off valve 41 and the gas side on-off valve 42 are closed, but by opening the bypass on-off valve 44 of the bypass piping 43, the refrigerant remaining in the indoor unit 20, the second refrigerant piping 52, the first refrigerant piping 51, the gas refrigerant piping 30, and the liquid refrigerant piping 31 can be recovered in the refrigerant recovery vessel.

[0029] Furthermore, in the event of a refrigerant leak, the control unit closes the liquid side on-off valve 41 and the gas side on-off valve 42 by stopping the power supply to the coils of the gas side on-off valve 41 and the liquid side on-off valve 42. This makes it possible to minimize refrigerant leakage. Furthermore, because the liquid side on-off valve 41 and the gas side on-off valve 42 are configured as normally closed type solenoid valves, if the power supply is stopped due to a power outage or other reason, the gas side on-off valve 41 and the liquid side on-off valve 42 will be in a closed state. This makes it possible to minimize refrigerant leakage even if the refrigerant piping is damaged after the power supply is stopped due to an earthquake or other reason.

[0030] [1-3. Effects, etc.] As described above, in this embodiment, the system comprises first refrigerant piping 51 connecting gas refrigerant piping 30 on the outdoor unit 10 side and gas refrigerant piping 30 on the indoor unit 20 side, second refrigerant piping 52 connecting liquid refrigerant piping 31 on the outdoor unit 10 side and liquid refrigerant piping 31 on the indoor unit 20 side, gas side on-off valve 42 provided on first refrigerant piping 51, liquid side on-off valve 41 provided on second refrigerant piping 52, bypass piping 43 connecting first refrigerant piping 51 on the indoor unit 20 side and second refrigerant piping 52 on the outdoor unit 10 side, and bypass on-off valve 44 provided on bypass piping 43, wherein gas side on-off valve 42 and liquid side on-off valve 41 are normally closed type solenoid valves, and bypass on-off valve 44 is an electrically operated valve or a manual valve, and is open during an airtightness test and when drawing a vacuum.

[0031] As a result, when performing an airtightness test of the refrigerant piping, vacuuming, or refrigerant recovery, by opening the bypass on-off valve 44 and connecting the bypass piping 43, even if normally closed type valves are used as the liquid side on-off valve 41 and the gas side on-off valve 42, it is possible to properly introduce nitrogen gas, vacuum, or recover refrigerant during an airtightness test over the entire gas refrigerant piping 30 and the liquid refrigerant piping 31. Therefore, even when power is not supplied, airtightness testing, evacuation, or refrigerant recovery can be performed without using a separate external power source, thereby reducing equipment costs.

[0032] In addition, in this embodiment, the gas side on-off valve 42 is configured by a pilot-type solenoid valve, and further includes a gas side bypass pipe 45 that is provided in the first refrigerant pipe 51 and bypasses the upstream side of the gas side on-off valve 42 and the downstream side of the gas side on-off valve 42, and the gas side bypass pipe 45 is provided with a check valve 46 that allows refrigerant to flow only from the indoor unit 20 side to the outdoor unit 10 side.

[0033] If a pilot-type normally closed solenoid valve is used for the gas side on-off valve 42, when the gas side on-off valve 42 is closed, the refrigerant will not pass through the gas side on-off valve 42 from the indoor unit 20 to the outdoor unit 10, even if the pressure difference from the indoor unit 20 to the outdoor unit 10 is large. As a result, a sufficient vacuum cannot be drawn in the first refrigerant piping 51. Therefore, in this embodiment, a check valve 46 is provided in the gas side bypass piping 45, which bypasses the gas side on-off valve 42 of the gas refrigerant piping 30. Therefore, when vacuuming, the air in the first refrigerant piping 51 is sucked from the indoor unit 20 to the outdoor unit 10 via the gas side bypass piping 45. As a result, vacuuming can be performed more efficiently.

[0034] (Embodiment 2) [2-1.Configuration] Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a schematic diagram showing a second embodiment of the present invention. 3, in this embodiment, a liquid side on-off valve 241, which is a normally closed type solenoid valve, is provided on the refrigerant pipe 24 of the indoor unit 20 connected to the liquid refrigerant pipe 31. In addition, a gas side on-off valve 242, which is a normally closed type solenoid valve, is provided on the refrigerant pipe 24 of the indoor unit 20 connected to the gas refrigerant pipe 30. The bypass piping 243 connects the refrigerant piping 24 on the outdoor unit 10 side of the liquid side on-off valve 241 to the refrigerant piping 24 on the indoor heat exchanger 21 side of the gas side on-off valve 242. A bypass on-off valve 244, which is an electrically operated valve, is provided midway through the bypass piping 243. The bypass pipe 243 may connect the refrigerant pipe 24 on the indoor heat exchanger 21 side of the liquid side on-off valve 241 to the refrigerant pipe 24 on the outdoor unit 10 side of the gas side on-off valve 242.

[0035] The gas-side bypass piping 245 connects the refrigerant piping 24 on the indoor heat exchanger 21 side of the gas-side on-off valve 242 to the refrigerant piping 24 on the outdoor unit 10 side of the gas-side on-off valve 242. The check valve 246 is provided midway along the gas-side bypass piping 245. The check valve 246 is a check valve that allows refrigerant to flow from the indoor heat exchanger 21 to the outdoor unit 10 side. The other configurations are the same as those in the first embodiment, so the same parts are given the same reference numerals and the description thereof will be omitted.

[0036] [2-2. Operation / effect] In this embodiment, similarly to the first embodiment, when an airtightness test is performed, the bypass on-off valve 244 is opened. As a result, nitrogen gas introduced from the service port 33 of the liquid refrigerant pipe 31 passes through the liquid refrigerant pipe 31 and the refrigerant pipe 24, and is introduced to the liquid-side on-off valve 241. In addition, nitrogen gas sent to the liquid-side refrigerant pipe 24 is introduced into the bypass pipe 243 along the way, flows into the refrigerant pipe 24 on the indoor heat exchanger 21 side through the gas-side on-off valve 242, and is introduced to the liquid-side on-off valve 241 via the indoor heat exchanger 21 and the liquid-side refrigerant pipe 24 in this order. On the other hand, nitrogen gas introduced from the service port 33 of the gas refrigerant pipe 30 flows through the gas refrigerant pipe 30 and the refrigerant pipe 24 connected to the gas refrigerant pipe 30, and is introduced into the gas side on-off valve 242. This makes it easier to introduce nitrogen gas into the entire area of ​​the gas refrigerant pipe 30, the liquid refrigerant pipe 31, and the refrigerant pipe 24.

[0037] As described above, in this embodiment, normally closed type valves are used for the liquid side on-off valve 41 and the gas side on-off valve 42, but by providing the bypass piping 243, when nitrogen gas is introduced from each service port 33, it is possible to introduce nitrogen gas throughout the gas refrigerant piping 30, liquid refrigerant piping 31, refrigerant piping 24, and indoor heat exchanger 21, thereby enabling proper airtightness inspection of the refrigerant piping.

[0038] Furthermore, when evacuating the inside of the refrigerant piping or recovering the refrigerant, by opening the bypass on-off valve 244 of the bypass piping 243, it is possible to perform evacuation and refrigerant recovery over the entire area of ​​the gas refrigerant piping 30, the liquid refrigerant piping 31, the indoor heat exchanger 21, and the refrigerant piping 24, as in the first embodiment.

[0039] [2-3. Effects, etc.] As described above, this embodiment includes refrigerant piping connected to the liquid refrigerant piping and gas refrigerant piping of the outdoor unit, an indoor heat exchanger connected to the refrigerant piping, a liquid side on-off valve provided on the liquid side refrigerant piping, a gas side on-off valve provided on the gas side refrigerant piping, a bypass piping that bypasses the liquid side refrigerant piping and the gas side refrigerant piping, and a bypass on-off valve provided on the bypass piping, wherein the gas side on-off valve and the liquid side on-off valve are normally closed type solenoid valves, the bypass piping is refrigerant piping that connects the refrigerant piping on the outdoor unit side of the liquid side on-off valve to the refrigerant piping on the indoor side heat exchanger side of the gas side on-off valve, and the bypass on-off valve is configured as an electric valve or a manual valve.

[0040] As a result, when performing an airtightness test, vacuuming, or pumping down of the refrigerant piping, by opening the bypass on-off valve 244 and opening the bypass piping 243, even if normally closed type valves are used for the liquid side on-off valve 241 and the gas side on-off valve 242, it is possible to introduce nitrogen gas, vacuum up, pump down, or recover refrigerant during an airtightness test over the entire area of ​​the gas refrigerant piping 30, the liquid refrigerant piping 31, the indoor heat exchanger 21, and the refrigerant piping 24.

[0041] (Embodiment 3) Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a schematic diagram showing a third embodiment of the present invention.

[0042] [3-1.Configuration] As shown in FIG. 4, in this embodiment, the bypass piping 343 is configured to bypass the second refrigerant piping 52 on the outdoor unit 10 side of the liquid side on-off valve 41 and the second refrigerant piping 52 on the indoor unit 20 side of the liquid side on-off valve 41. The bypass piping 343 may connect the first refrigerant piping 51 on the outdoor unit 10 side of the gas side on-off valve 42 to the first refrigerant piping 51 on the indoor unit side of the gas side on-off valve 42. Further, in the middle of the bypass pipe 343, a bypass on-off valve 344 is provided, as in the first embodiment. The other configurations are the same as those in the first embodiment, so the same parts are given the same reference numerals and the description thereof will be omitted.

[0043] [3-2. Operation / effect] In this embodiment, similarly to the first embodiment, when an airtightness test is performed, the bypass on-off valve 344 is opened. As a result, nitrogen gas introduced from the service port 33 of the liquid refrigerant piping 31 passes through the liquid refrigerant piping 31 and the second refrigerant piping 52 and is introduced to the liquid side on-off valve 41. In addition, nitrogen gas sent to the second refrigerant piping 52 is introduced into the bypass piping 343 along the way, and is introduced to the liquid side on-off valve 42 via the second refrigerant piping 52 on the indoor unit 20 side, the liquid refrigerant piping 31, the indoor unit 20, the gas refrigerant piping 30, and the first refrigerant piping 51 in that order. On the other hand, nitrogen gas introduced from the service port 33 of the gas refrigerant pipe 30 flows through the gas refrigerant pipe 30 and the first refrigerant pipe 51, and is introduced into the gas side on-off valve . This makes it easier to introduce nitrogen gas into the entire area of ​​the gas refrigerant pipe 30 and the liquid refrigerant pipe 31.

[0044] As described above, in the present embodiment, normally closed type valves are used for the liquid side on-off valve 41 and the gas side on-off valve 42, but by providing the bypass piping 343, when nitrogen gas is introduced from each service port 33, nitrogen gas can be introduced throughout the entire gas refrigerant piping 30, liquid refrigerant piping 31, second refrigerant piping 52, and first refrigerant piping 51, and an airtightness inspection of the refrigerant piping can be performed properly.

[0045] Furthermore, when the inside of the refrigerant piping is evacuated to recover the refrigerant, the provision of the gas side bypass piping 45 and the check valve 46 allows for efficient evacuation.

[0046] [3-3. Effects, etc.] As described above, in this embodiment, the system comprises first refrigerant piping 51 connecting gas refrigerant piping 30 on the outdoor unit 10 side with gas refrigerant piping 30 on the indoor unit 20 side, second refrigerant piping 52 connecting liquid refrigerant piping 31 on the outdoor unit 10 side with liquid refrigerant piping 31 on the indoor unit 20 side, gas side on-off valve 42 provided on first refrigerant piping 51, liquid side on-off valve 41 provided on second refrigerant piping 52, bypass piping 343 connecting second refrigerant piping 52 on the outdoor unit 10 side with second refrigerant piping 52 on the indoor unit 20 side, and bypass on-off valve 344 provided on bypass piping 343, where gas side on-off valve 42 and liquid side on-off valve 41 are normally closed type solenoid valves, and the bypass on-off valve is an electrically operated valve or a manual valve, and is open during an airtightness test and when drawing a vacuum.

[0047] As a result, when performing an airtightness test, vacuuming, or pumping down of the refrigerant piping, by opening the bypass on-off valve 344 and opening the bypass piping 343, even if normally closed type valves are used for the liquid side on-off valve 41 and the gas side on-off valve 42, it is possible to introduce nitrogen gas, vacuum up, pump down, or recover refrigerant during an airtightness test over the entire gas refrigerant piping 30, liquid refrigerant piping 31, indoor heat exchanger 21, and refrigerant piping 24.

[0048] The bypass piping 343 is a piping that connects the second refrigerant piping 52 on the outdoor unit 10 side with the second refrigerant piping 52 on the indoor unit 20 side, and the gas side on-off valve 42 is composed of a pilot-type solenoid valve, and further includes a gas side bypass piping 45 that is provided on the first refrigerant piping 51 and bypasses the upstream side of the gas side on-off valve 42 and the downstream side of the gas side on-off valve 42, and the gas side bypass piping 45 is provided with a check valve 46 that only allows the refrigerant to flow from the indoor unit 20 side to the outdoor unit 10 side.

[0049] If a pilot-type normally closed solenoid valve is used for the gas side on-off valve 42, when the gas side on-off valve 42 is closed, the refrigerant will not pass through the gas side on-off valve 42 from the indoor unit 20 to the outdoor unit 10, even if the pressure difference from the indoor unit 20 to the outdoor unit 10 is large. As a result, a sufficient vacuum cannot be drawn in the first refrigerant piping 51. Therefore, in this embodiment, a check valve 46 is provided in the gas side bypass piping 45, which bypasses the gas side on-off valve 42 of the gas refrigerant piping 30. Therefore, when vacuuming, the air in the first refrigerant piping 51 is sucked from the indoor unit 20 to the outdoor unit 10 via the gas side bypass piping 45. As a result, vacuuming can be performed more efficiently.

[0050] (Fourth embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIG. [4-1.Configuration] FIG. 5 is a schematic diagram showing a fourth embodiment of the present invention. 5, in this embodiment, a normally closed type liquid side on-off valve 441 is provided on the refrigerant piping 24 of the indoor unit 20 connected to the liquid refrigerant piping 31. Also, a normally closed type gas side on-off valve 442 is provided on the refrigerant piping 24 of the indoor unit 20 connected to the gas refrigerant piping 30.

[0051] The bypass piping 443 connects the refrigerant piping 24 on the outdoor unit 10 side of the liquid side on-off valve 441 to the refrigerant piping 24 on the indoor heat exchanger 21 side of the liquid side on-off valve 441. The bypass on-off valve 444 is provided midway along the bypass piping 443. The gas side bypass piping 445 connects the refrigerant piping 24 on the indoor heat exchanger 21 side of the gas side on-off valve 442 to the refrigerant piping 24 on the outdoor unit 10 side of the gas side on-off valve 442. The check valve 446 is provided midway along the gas side bypass piping 445. The bypass pipe 443 may be connected to the refrigerant pipe 24 on the outdoor unit 10 side of the gas side on-off valve 442 and the refrigerant pipe 24 on the indoor heat exchanger 21 side of the gas side on-off valve 442. The other configurations are the same as those in the first embodiment, so the same parts are given the same reference numerals and the description thereof will be omitted.

[0052] [4-2. Operation / effect] In this embodiment, similarly to the first to third embodiments, when an airtightness test is performed, the bypass on-off valve 444 is opened. As a result, nitrogen gas introduced from the service port 33 of the liquid refrigerant pipe 31 passes through the liquid refrigerant pipe 31 and the refrigerant pipe 24, and is introduced to the liquid side on-off valve 441. In addition, nitrogen gas sent to the liquid side refrigerant pipe 24 is introduced into the bypass pipe 443 along the way, flows into the refrigerant pipe 24 on the indoor side heat exchanger 21 side from the liquid side on-off valve 441, and is introduced to the gas side on-off valve 442 via the liquid side refrigerant pipe 24, the indoor side heat exchanger 21, and the gas side refrigerant pipe 24 in this order. On the other hand, nitrogen gas introduced from the service port 33 of the gas refrigerant pipe 30 flows through the gas refrigerant pipe 30 and is introduced up to the gas side on-off valve 442. This allows nitrogen gas to be introduced into the entire gas refrigerant pipe 30, the liquid refrigerant pipe 31, the indoor heat exchanger 21, and the refrigerant pipe 24.

[0053] In addition, when vacuuming the inside of the refrigerant piping and recovering the refrigerant, the provision of gas side bypass piping 445 and check valve 446 allows for efficient vacuuming (the action and effect are the same as those described in [1-2. Operation and Action], so explanation will be omitted).

[0054] [4-3. Effects, etc.] As described above, this embodiment includes the refrigerant piping 24 connected to the liquid refrigerant piping 31 and gas refrigerant piping 30 of the outdoor unit 10, the indoor heat exchanger 21 connected to the refrigerant piping 24, a liquid side on-off valve 441 provided on the liquid side refrigerant piping 24, a gas side on-off valve 442 provided on the gas side refrigerant piping 24, a bypass piping 443 connecting the refrigerant piping 24 on the outdoor unit 10 side of the liquid side on-off valve 441 to the refrigerant piping 24 on the indoor side heat exchanger 21 side of the liquid side on-off valve 441, and a bypass on-off valve 444 provided on the bypass piping 443, wherein the gas side on-off valve 442 and the liquid side on-off valve 441 are normally closed type solenoid valves, and the bypass on-off valve 444 is configured as an electric valve or a manual valve.

[0055] As a result, when performing an airtightness test, vacuuming, or pumping down of the refrigerant piping, by opening the bypass on-off valve 444 and opening the bypass piping 443, even if normally closed type valves are used for the liquid side on-off valve 441 and the gas side on-off valve 442, it is possible to introduce nitrogen gas, vacuum up, pump down, or recover refrigerant during an airtightness test over the entire area of ​​the gas refrigerant piping 30, the liquid refrigerant piping 31, the indoor heat exchanger 21, and the refrigerant piping 24.

[0056] (Embodiment 5) Next, a fifth embodiment of the present invention will be described with reference to FIG. [5-1.Configuration] FIG. 6 is a schematic diagram showing a fifth embodiment of the present invention. As shown in FIG. 6, in this embodiment, the bypass piping 543 connects the second refrigerant piping 52 on the indoor unit 20 side of the liquid side on-off valve 41 to the first refrigerant piping 51 on the outdoor unit 10 side of the gas side on-off valve 42. A bypass on-off valve 544 is provided in the bypass piping 543. A check valve 547 is provided in the bypass piping 543 on the first refrigerant piping 51 side of the bypass on-off valve 544. An expansion mechanism 548 is provided in the bypass piping 543 on the second refrigerant piping 52 side of the bypass on-off valve 544. The other configurations are the same as those in the first embodiment, so the same parts are given the same reference numerals and the description thereof will be omitted.

[0057] [5-2. Operation / effect] In this embodiment, similarly to the first to fourth embodiments, when an airtightness test is performed, the bypass on-off valve 544 is opened. As a result, nitrogen gas introduced from the service port 33 of the liquid refrigerant pipe 31 passes through the liquid refrigerant pipe 31 and the second refrigerant pipe 52 and is introduced to the liquid side on-off valve 41. Furthermore, nitrogen gas sent from the service port 33 of the gas refrigerant piping 30 to the first refrigerant piping 51 is introduced into the bypass piping 543 along the way, and then passes through the second refrigerant piping 52, the gas refrigerant piping 31 between the shutoff valve kit 40 and the indoor unit 20, the indoor unit 20, the liquid refrigerant piping 30 between the shutoff valve kit 40 and the indoor unit 20, and the second refrigerant piping 52 in this order, before being introduced to the liquid-side on-off valve 41.

[0058] This allows nitrogen gas to be introduced into the entire gas refrigerant pipe 30, the liquid refrigerant pipe 31, the indoor heat exchanger 21, and the refrigerant pipe 24. The same applies when the inside of the refrigerant pipe is evacuated and the refrigerant is recovered.

[0059] In this embodiment, the shutoff valve kit 40 has a function of preventing refrigerant from accumulating on the gas refrigerant pipe 30 side. That is, when the thermostat is off or during defrosting operation, the gas side on-off valve 42 is closed and the bypass on-off valve 544 is opened. Also, the on-off valve 34 on the indoor unit 20 side is closed. As a result, the refrigerant from the compressor 11 returns to the outdoor unit 10 via the gas refrigerant piping 30, the first refrigerant piping 51, the bypass piping 43, the check valve 547, the bypass on-off valve 544, the expansion mechanism 548, the liquid refrigerant piping 30, and the liquid side on-off valve 41. As a result, the refrigerant does not flow to the indoor unit 20 side, thereby suppressing unnecessary heat exchange. Therefore, the refrigerant can be prevented from accumulating on the gas refrigerant pipe 30 side. In addition, during defrosting operation, heat dissipation is prevented by not flowing refrigerant to the indoor unit 20 side, and as a result, all of the heat of the gas discharged from the compressor 11 can be used to defrost the outdoor heat exchanger 13.

[0060] [5-3. Effects, etc.] As described above, in this embodiment, the bypass piping 543 connects the first refrigerant piping 51 on the indoor unit 20 side of the liquid side on-off valve 41 to the second refrigerant piping 52 on the outdoor unit 10 side of the gas side on-off valve 42, and the bypass piping 543 is provided with a bypass on-off valve 544 and a check valve 547, and the expansion mechanism 548 is provided on the bypass piping 543 on the second refrigerant piping 52 side of the bypass on-off valve 544.

[0061] As a result, when performing an airtightness test of the refrigerant piping, vacuuming, or refrigerant recovery, by opening the bypass on-off valve 544 and connecting the bypass piping 543, even if normally closed type valves are used for the liquid side on-off valve 41 and the gas side on-off valve 42, it is possible to properly introduce nitrogen gas, vacuum, or recover refrigerant during an airtightness test over the entire area of ​​the gas refrigerant piping 30 and the liquid refrigerant piping 31. In addition, during defrosting operation, heat radiation is prevented by not flowing refrigerant to the indoor unit 20 side, so refrigerant is prevented from accumulating on the gas refrigerant piping 30 side, and all of the heat of the gas discharged from the compressor 11 can be used to defrost the outdoor heat exchanger 13.

[0062] (Other embodiments) As described above, Embodiments 1 to 5 have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to these and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made. Furthermore, it is also possible to combine the components described in the above embodiments to create new embodiments. Therefore, other embodiments will be exemplified below.

[0063] In the first to fifth embodiments, a motor-operated valve has been described as an example of a bypass on-off valve. The bypass on-off valve may be any valve that can be opened when the commercial power supply is not energized. Therefore, the bypass on-off valve is not limited to a motor-operated valve. However, if a motor-operated valve is used as the bypass on-off valve, the opening and closing of the motor-operated valve can be controlled by the control unit. Furthermore, a manual valve may be used as the bypass on-off valve. Using a manual valve as the bypass on-off valve can reduce costs. Furthermore, since there is no need to link with the control unit of the indoor unit, a shutoff valve kit can be easily attached externally.

[0064] In the first embodiment, the bypass piping connects the first refrigerant piping on the indoor unit side of the gas side on-off valve to the second refrigerant piping on the outdoor unit side of the liquid side on-off valve, but the present invention is not limited to this configuration. The first refrigerant piping on the outdoor unit side of the gas side on-off valve may be connected to the second refrigerant piping on the indoor unit side of the liquid side on-off valve. In the first and second embodiments, the gas-side bypass piping is provided on the first refrigerant piping side. The gas-side bypass piping may be configured to bypass the pilot valve. Therefore, the present invention is not limited to a configuration in which the gas-side bypass piping is provided on the first refrigerant piping side. For example, if the liquid-side on-off valve is a pilot valve, the second refrigerant piping may be provided with a liquid-side bypass piping that bypasses the liquid-side on-off valve, and the liquid-side bypass piping may be provided with a check valve that allows refrigerant to flow from the indoor unit to the outdoor unit.

[0065] In the third embodiment, the bypass pipe is provided on the second refrigerant pipe, but the present invention is not limited to this. For example, the bypass pipe may be provided on the first refrigerant pipe. In the first and third embodiments, a so-called single-type air conditioner in which one indoor unit is connected to one outdoor unit has been described, but the present invention is not limited to this and can also be applied to a so-called multi-type air conditioner in which multiple indoor units are connected to one outdoor unit. When using a multi-type air conditioner, approximately two to four indoor units are connected to one shutoff valve kit. This configuration also achieves the same effects as the first and third embodiments. In the first to fourth embodiments, the bypass on-off valve is set in an open state when the shutoff valve kit is installed, but the bypass on-off valve may be set in an open state from the time of shipment from the factory. In the fifth embodiment, the bypass on-off valve 544 is disposed closer to the first refrigerant pipe 51 than the check valve 547 and the expansion mechanism 548, but the present invention is not limited to this. The same effect can be achieved by disposing the bypass on-off valve 544 between the check valve 547 and the expansion mechanism 548, or by disposing the bypass on-off valve 544 closer to the second refrigerant pipe 52 than the expansion mechanism 548. [Industrial Applicability]

[0066] As described above, the present disclosure can be suitably used as an air conditioning apparatus that can perform airtight testing, vacuuming, or pumping down over the entire gas refrigerant piping and liquid refrigerant piping without using an external power source, even when normally closed type valves are used for the gas side on-off valve and the liquid side on-off valve. [Explanation of symbols]

[0067] 1. Air conditioning equipment 10 Outdoor unit 11 Compressor 12 Four-way valve 13 Outdoor heat exchanger 15 Refrigerant piping 20 Indoor unit 21 Indoor heat exchanger 24 Refrigerant piping 30 Gas refrigerant piping 31 Liquid refrigerant piping 32 Service valve 33 Service Port 34 On-off valve 40 Shut-off Valve Kit 41,241,442 Gas side on-off valve 42,242,441 Liquid side shut-off valve 43,243,343,543 Bypass piping 44,244,344,544 Bypass valve 45,245,445 Gas side bypass piping 46,246 Check valve 51 First refrigerant piping 52 Second refrigerant piping 547 Check valve 548 Expansion Mechanism

Claims

[Claim 1] A shut-off valve kit comprising: a first refrigerant pipe connecting a gas refrigerant pipe on an outdoor unit side and the gas refrigerant pipe on an indoor unit side; a second refrigerant pipe connecting a liquid refrigerant pipe on the outdoor unit side and the liquid refrigerant pipe on the indoor unit side; a gas side on-off valve provided on the first refrigerant pipe; a liquid side on-off valve provided on the second refrigerant pipe; a bypass pipe connecting the first refrigerant pipe on the outdoor unit side and the second refrigerant pipe on the indoor unit side, or connecting the first refrigerant pipe on the indoor unit side and the second refrigerant pipe on the outdoor unit side; and a bypass on-off valve provided on the bypass pipe, wherein the gas side on-off valve and the liquid side on-off valve are normally closed type solenoid valves, and the bypass on-off valve is an electric valve or a manual valve, the shut-off valve kit being opened during an airtightness test and when drawing a vacuum, and being installed in the state where the bypass on-off valve is open. How to open and close a shutoff valve kit.

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