Refrigeration cycle device

Abstract

A refrigerant circuit of this refrigeration cycle device includes: a heat-source-side refrigerant channel (111) that includes a heat-source-side heat exchanger (2); a use-side refrigerant channel (112) that includes a use-side heat exchanger (3); and first extension piping (113) and second extension piping (114). The total internal volume Vout (units: m3) of the heat-source-side heat exchanger is represented by the relational expression (1), when the total internal volume of the use-side heat exchanger is Vin (units: m3), the maximum internal diameter of the first extension piping is dL (units: m), the maximum internal diameter of the second extension piping is dG (units: m), the maximum value of the piping lengths of the first extension piping and the second extension piping is L (units: m), the saturated liquid density of a refrigerant at a temperature that is the same as the maximum value Tmax of the ambient temperature of the refrigerant circuit when the refrigeration cycle device is securely active is ρL (units: kg / m3), and the saturated gas density of the refrigerant at a temperature that is the same as the maximum value Tmax is ρG (units: kg / m3).

Description

Refrigeration cycle equipment

[0001] The present disclosure relates to a refrigeration cycle device.

[0002] In recent years, from the viewpoint of reducing the environmental impact of refrigeration cycle devices, there has been a demand for the use of refrigerants with low GWP (Global Warming Potential) as refrigerants for use in refrigeration cycle devices. Many low-GWP refrigerants are flammable and toxic, and in order to ensure safety, refrigeration cycle devices using such refrigerants are required to reduce the amount of refrigerant charged into a refrigerant circuit (hereinafter also referred to as the refrigerant charge amount) and the amount of refrigerant leaking from the refrigerant circuit into a room where a user-side heat exchanger is located (hereinafter also referred to as the refrigerant leakage amount), compared to conventional refrigeration cycle devices using high-GWP refrigerants.

[0003] Japanese Patent Laid-Open Publication No. 11-159984 (Patent Document 1) discloses a forced convection heat exchanger for refrigeration and air conditioning in which the cross-sectional shape of the refrigerant pipes is elliptical or flattened in order to reduce the amount of refrigerant charged.

[0004] Japanese Patent Application Publication No. 11-159984

[0005] When the volumes of the heat exchanger, accumulator, receiver, etc. included in the refrigerant circuit are reduced in order to reduce the amount of low GWP refrigerant charged, it is difficult to reduce the amount of refrigerant leakage.

[0006] To reduce the amount of refrigerant leakage, when refrigerant leakage into the room is detected, it is necessary to recover the refrigerant remaining in the refrigerant circuit to a heat source side refrigerant flow path including a heat source side heat exchanger, accumulator, receiver, etc. Therefore, if the volume of the heat exchanger, accumulator, receiver, etc. is reduced, the amount of recoverable refrigerant is also reduced, making it difficult to suppress the leakage of unrecoverable refrigerant.

[0007] A primary object of the present disclosure is to provide a refrigeration cycle device that can simultaneously reduce the amount of refrigerant charged and the amount of refrigerant leakage.

[0008] A refrigeration cycle apparatus according to a first aspect of the present disclosure is a refrigeration cycle apparatus including a refrigerant circuit through which a refrigerant circulates. The refrigerant circuit includes a heat-source-side refrigerant flow path including a compressor and a heat-source-side heat exchanger, a utilization-side refrigerant flow path including a utilization-side heat exchanger, and first and second extension pipes connecting the heat-source-side refrigerant flow path and the utilization-side refrigerant flow path. The refrigeration cycle apparatus further includes a control device that switches between a cooling operation mode and a recovery operation mode in which the refrigerant is recovered to the heat-source-side refrigerant flow path. In the cooling operation mode, the heat-source-side heat exchanger functions as a condenser, and the utilization-side heat exchanger functions as an evaporator, and the refrigerant flows sequentially through the compressor, the heat-source-side heat exchanger, the first extension pipe, the utilization-side heat exchanger, and the second extension pipe. The heat-source-side refrigerant flow path includes a first control valve disposed between the heat-source-side heat exchanger and the first extension pipe. The first control valve is controlled to open in the cooling operation mode and to close in the recovery operation mode. When the total internal volume of the utilization-side heat exchanger is V in (unit: m 3 ), the maximum inner diameter of the first extension pipe is d L (unit: m), the maximum inner diameter of the second extension pipe is d G (unit: m), the maximum length of each of the first extension pipe and the second extension pipe is L (unit: m), and the upper limit value T of the ambient temperature of the refrigerant circuit at which the operation of the refrigeration cycle device is guaranteed. max The saturated liquid density of the refrigerant at the same temperature is ρ L (unit: kg / m 3 ), upper limit T max The saturated gas density of the refrigerant at the same temperature is ρ G (unit: kg / m 3 ) When the total internal volume of the heat source side heat exchanger is V out (unit: m 3 ) is expressed by the following relational expression (1).

[0009]

[0010] A refrigeration cycle apparatus according to a second aspect of the present disclosure includes a refrigerant circuit through which a refrigerant circulates. The refrigerant circuit includes a heat-source-side refrigerant flow path including a compressor and a heat-source-side heat exchanger, a utilization-side refrigerant flow path including a utilization-side heat exchanger, and first and second extension pipes connecting the heat-source-side refrigerant flow path and the utilization-side refrigerant flow path. The refrigeration cycle apparatus further includes a control device that switches between a cooling operation mode and a recovery operation mode in which the refrigerant is recovered to the heat-source-side refrigerant flow path. In the cooling operation mode, the heat-source-side heat exchanger functions as a condenser and the utilization-side heat exchanger functions as an evaporator, and the refrigerant flows sequentially through the compressor, the heat-source-side heat exchanger, the first extension pipe, the utilization-side heat exchanger, and the second extension pipe. The heat source side refrigerant flow path includes a first control valve arranged between the heat source side heat exchanger and the first extension pipe, a first branch path branching from the first refrigerant flow path connecting the heat source side heat exchanger and the first control valve, at least one on-off valve for opening and closing the first branch path, and a container connected to the first refrigerant flow path via the first branch path and the at least one on-off valve and capable of recovering refrigerant. The first control valve is controlled to open in the cooling operation mode and to close in the recovery operation mode. The at least one on-off valve is controlled to close in the cooling operation mode and to open in the recovery operation mode. When the total internal volume of the utilization side heat exchanger is V in (unit: m 3 ), the maximum inner diameter of the first extension pipe is d L (unit: m), the maximum inner diameter of the second extension pipe is d G (unit: m), the maximum length of each of the first extension pipe and the second extension pipe is L (unit: m), and the upper limit value T of the ambient temperature of the refrigerant circuit at which the operation of the refrigeration cycle device is guaranteed. max The saturated liquid density of the refrigerant at the same temperature is ρ L (unit: kg / m 3 ), upper limit T max The saturated gas density of the refrigerant at the same temperature is ρ G (unit: kg / m 3 ) When the total internal volume of the heat source side heat exchanger is V out (unit: m 3 ) and the internal volume V of the container C is expressed by the following relational expression (2).

[0011]

[0012] A refrigeration cycle apparatus according to a third aspect of the present disclosure includes a refrigerant circuit through which a refrigerant circulates. The refrigerant circuit includes a heat-source-side refrigerant flow path including a compressor and a heat-source-side heat exchanger, a utilization-side refrigerant flow path including a utilization-side heat exchanger, and first and second extension pipes connecting the heat-source-side refrigerant flow path and the utilization-side refrigerant flow path. The refrigeration cycle apparatus further includes a control device that switches between a heating operation mode and a recovery operation mode in which the refrigerant is recovered to the heat-source-side refrigerant flow path. In the heating operation mode, the utilization-side heat exchanger functions as a condenser, and the heat-source-side heat exchanger functions as an evaporator, and the refrigerant flows sequentially through the compressor, the second extension pipe, the utilization-side heat exchanger, the first extension pipe, and the heat-source-side heat exchanger. The heat source side refrigerant flow path includes a second control valve arranged between the second extension pipe and the suction port of the compressor, a second branch path branching from the second refrigerant flow path connecting the second control valve and the suction port, at least one on-off valve for opening and closing the second branch path, and a container connected to the second refrigerant flow path via the second branch path and the at least one on-off valve and capable of recovering refrigerant. The second control valve is controlled to open in the heating operation mode and to close in the recovery operation mode. The at least one on-off valve is controlled to close in the heating operation mode and to open in the recovery operation mode. When the total internal volume of the user side heat exchanger is V in (unit: m 3 ), the maximum inner diameter of the first extension pipe is d L (unit: m), the maximum inner diameter of the second extension pipe is d G (unit: m), the maximum length of each of the first extension pipe and the second extension pipe is L (unit: m), and the upper limit value T of the ambient temperature of the refrigerant circuit at which the operation of the refrigeration cycle device is guaranteed. max The saturated liquid density of the refrigerant at the same temperature is ρ L (unit: kg / m 3 ), upper limit T max The saturated gas density of the refrigerant at the same temperature is ρ G (unit: kg / m 3 ) when the internal volume of the container V C is expressed by the following relational expression (3).

[0013]

[0014] According to the present disclosure, it is possible to provide a refrigeration cycle device that can simultaneously reduce the amount of refrigerant filled and the amount of refrigerant leakage.

[0015] FIG. 1 is a diagram for explaining a refrigeration cycle device according to embodiment 1. FIG. 2 is a diagram for explaining a modified example of the refrigeration cycle device according to embodiment 1. FIG. 3 is a diagram for explaining a refrigeration cycle device according to embodiment 2. FIG. 4 is a diagram for explaining a first modified example of the refrigeration cycle device according to embodiment 2. FIG. 5 is a diagram for explaining a second modified example of the refrigeration cycle device according to embodiment 2. FIG. 6 is a diagram for explaining a refrigeration cycle device according to embodiment 3. FIG. 7 is a diagram for explaining a first modified example of the refrigeration cycle device according to embodiment 3. FIG. 8 is a diagram for explaining a second modified example of the refrigeration cycle device according to embodiment 3.

[0016] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. While multiple embodiments will be described below, they are merely examples and are not intended to limit the scope of the present invention. Appropriate combinations and substitutions of the configurations described in each embodiment are contemplated from the beginning of the application. The drawings show the connections of the main components of the refrigeration cycle device according to the present embodiment, but do not necessarily show the physical spatial arrangement of each component. Furthermore, the drawings do not show all the components of the refrigeration cycle device according to the present embodiment. The refrigeration cycle device according to the present embodiment may include components not shown. The same or corresponding parts in the drawings are designated by the same reference numerals, and descriptions thereof will not be repeated.

[0017] First Embodiment <Configuration of Refrigeration Cycle Apparatus> As shown in Fig. 1 , a refrigeration cycle apparatus 100 according to a first embodiment includes a refrigerant circuit 110 through which a refrigerant circulates, and a control device 200.

[0018] The refrigerant circuit 110 includes a heat source side refrigerant flow path 111 , a usage side refrigerant flow path 112 , and a first extension pipe 113 and a second extension pipe 114 connecting the heat source side refrigerant flow path 111 and the usage side refrigerant flow path 112 .

[0019] The refrigerant is a refrigerant having a GWP lower than that of R32, such as a mixed refrigerant containing R32 and R1234yf, a mixed refrigerant containing R32 and R1123, a mixed refrigerant containing R32 and R1132(E), a mixed refrigerant containing R290 and R1123, a mixed refrigerant containing R290 and R1132(E), or R290.

[0020] The heat source side refrigerant flow path 111 is housed in the heat source side unit 121. The heat source side refrigerant flow path 111 includes a compressor 1, a heat source side heat exchanger 2, a flow path switching device 4, an expansion device 5, a first shutoff valve 6 (first control valve), and a second shutoff valve 7.

[0021] The use-side refrigerant flow path 112 is housed in the use-side unit 122. The use-side refrigerant flow path 112 includes the use-side heat exchanger 3.

[0022] The compressor 1 compresses a refrigerant, and is, for example, a rotary compressor, a scroll compressor, a screw compressor, or a reciprocating compressor.

[0023] The heat source-side heat exchanger 2 is provided so that the refrigerant circulating through the refrigerant circuit exchanges heat with the air outside the room. The refrigeration cycle apparatus 100 is equipped with a heat source-side fan (not shown) for supplying the air outside the room to the heat source-side heat exchanger 2.

[0024] The utilization-side heat exchanger 3 is provided so that the refrigerant circulating through the refrigerant circuit exchanges heat with the air in the living room. The refrigeration cycle device 100 is provided with a utilization-side fan (not shown) for supplying the air in the living room to the utilization-side heat exchanger 3.

[0025] Each of the heat source-side heat exchanger 2 and the user-side heat exchanger 3 has a flow path through which the refrigerant flows, for example, a pair of headers and a plurality of heat transfer tubes connected in parallel to the pair of headers. In this specification, the total volume of the flow paths through which the refrigerant flows in the heat source-side heat exchanger 2 or the user-side heat exchanger 3 is referred to as the total internal volume of the heat source-side heat exchanger 2 or the total internal volume of the user-side heat exchanger 3.

[0026] The flow path switching device 4 switches between a first state in which the discharge port of the compressor 1 is connected to the heat source side heat exchanger 2 and the suction port of the compressor 1 is connected to the user side heat exchanger 3, and a second state in which the discharge port of the compressor 1 is connected to the user side heat exchanger 3 and the suction port of the compressor 1 is connected to the heat source side heat exchanger 2. The switching by the flow path switching device 4 is controlled by a control device 200, which will be described later. The flow path switching device 4 is, for example, a four-way valve or a six-way valve.

[0027] The expansion device 5 expands the refrigerant to reduce its pressure. The expansion device 5 is, for example, an electric expansion valve. Note that the expansion device 5 is not limited to an electric expansion valve, and may be a mechanical expansion valve employing a diaphragm in a pressure receiving portion, or a capillary tube.

[0028] The first shutoff valve 6 is disposed between the heat source-side heat exchanger 2 and the first extension pipe 113. The first shutoff valve 6 is disposed, for example, between the expansion device 5 and the first extension pipe 113. Preferably, the first shutoff valve 6 is disposed near the connection between the heat source-side refrigerant flow path 111 and the first extension pipe 113.

[0029] The second shutoff valve 7 is disposed between the second extension pipe 114 and the compressor 1. The second shutoff valve 7 is disposed, for example, between the second extension pipe 114 and the flow path switching device 4. Preferably, the second shutoff valve 7 is disposed near the connection between the heat source side refrigerant flow path 111 and the second extension pipe 114.

[0030] The first shut-off valve 6 and the second shut-off valve 7 are each a control valve whose opening degree is controlled by a control device 200 described later. The first shut-off valve 6 is fully open in a normal operation mode described later, and is fully closed in a recovery operation mode described later. The second shut-off valve 7 is fully open in the normal operation mode described later, and is fully closed after the recovery operation mode described later ends. The first shut-off valve 6 and the second shut-off valve 7 are each, for example, an electrically operated shut-off valve. Note that the method of shut-off operation of each of the first shut-off valve 6 and the second shut-off valve 7 is not limited to being electrically operated.

[0031] Each of the first shutoff valve 6 and the second shutoff valve 7 may be capable of shutting off refrigerant flowing in only one direction, or may be capable of shutting off refrigerant flowing in both directions. When each of the first shutoff valve 6 and the second shutoff valve 7 has the ability to shut off refrigerant flowing in only one direction, each of the first shutoff valve 6 and the second shutoff valve 7 is installed in an orientation that prevents refrigerant from moving from the heat source side refrigerant flow path 111 to the user side refrigerant flow path 112.

[0032] The first extension pipe 113 and the second extension pipe 114 are each stretched between the heat source side unit 121 and the user side unit 122. The first extension pipe 113 connects one end of the heat source side refrigerant flow path 111 to one end of the user side refrigerant flow path 112. The first extension pipe 113 is arranged in the refrigerant circuit between an expansion device 5 (described later) included in the heat source side refrigerant flow path 111 and the user side heat exchanger 3. The second extension pipe 114 connects the other end of the heat source side refrigerant flow path 111 to the other end of the user side refrigerant flow path 112. The second extension pipe 114 is arranged in the refrigerant circuit between the user side heat exchanger 3 and the compressor 1.

[0033] The piping length of each of the first extension pipe 113 and the second extension pipe 114 may be adjustable in the specifications of the refrigeration cycle apparatus 100 (for example, specifications described in the user's guide of the refrigeration cycle apparatus 100, etc.). As in known refrigeration cycle apparatuses in which the piping length of the extension pipes is adjustable, when the piping length of each of the first extension pipe 113 and the second extension pipe 114 is adjustable, the maximum piping length of each of the first extension pipe 113 and the second extension pipe 114 is set in the above specifications. Note that the piping length of each of the first extension pipe 113 and the second extension pipe 114 may not be adjustable in the specifications of the refrigeration cycle apparatus 100.

[0034] The refrigerant circuit 110 does not include an accumulator or a receiver. The heat source side heat exchanger 2 has the largest volume among the components of the heat source side refrigerant flow path 111, for example.

[0035] The control device 200 switches the operation mode of the refrigeration cycle device 100. The control device 200 switches between a normal operation mode and a recovery operation mode. The control device 200 can switch the normal operation mode between, for example, a cooling operation mode and a heating operation mode. The cooling operation mode, heating operation mode, and recovery operation mode will be described later.

[0036] The control device 200 includes a processor 201 and a memory 202. The processor 201 is a computing entity that executes various programs. The memory 202 provides a storage area for storing program code, various variables, and the like when the processor 201 executes the various programs. The control device 200 is connected to each component of the refrigeration cycle device 100 and various sensors that detect the states of each component, and controls each component based on operating conditions set by a user via a remote control and signals output from each sensor. The control device 200 controls, for example, the frequency of the compressor 1, the rotation speeds of the fans near the heat source side heat exchanger 2 and the user side heat exchanger 3, the switching of the flow path switching device 4, the opening and closing of the first shutoff valve 6 and the second shutoff valve 7, and the opening degree of the expansion device 5.

[0037] The refrigeration cycle apparatus 100 further includes at least one sensor 300 for detecting refrigerant leakage from the use-side refrigerant flow path 112 in the room. The at least one sensor 300 outputs a signal to the control device 200. The control device 200 detects refrigerant leakage based on the signal output from the sensor 300.

[0038] The at least one sensor 300 is housed, for example, in the user-side unit 122. The at least one sensor 300 is, for example, at least one of a gas detection sensor that detects gas contained in the refrigerant and a pressure sensor that detects a pressure change in the user-side refrigerant flow path 112. The refrigeration cycle apparatus 100 may be provided with a plurality of sensors 300 of the same type or different types.

[0039] <Operation Modes of Refrigeration Cycle Apparatus> As described above, the refrigeration cycle apparatus 100 has the cooling operation mode, the heating operation mode, and the recovery operation mode as operation modes.

[0040] In the cooling operation mode, the first shutoff valve 6 and the second shutoff valve 7 are opened, and the flow path switching device 4 is set to the first state. In the cooling operation mode, the heat source side heat exchanger 2 acts as a condenser, and the user side heat exchanger 3 acts as an evaporator. The solid arrows in Fig. 1 indicate the direction of refrigerant flow in the cooling operation mode.

[0041] In the cooling operation mode, the refrigerant flows sequentially through the compressor 1, the heat source side heat exchanger 2, the expansion device 5, the first shutoff valve 6, the first extension pipe 113, the user side heat exchanger 3, the second extension pipe 114, and the second shutoff valve 7. Specifically, the high-pressure gas refrigerant discharged from the compressor 1 flows into the heat source side heat exchanger 2 via the flow switching device 4, where it exchanges heat with the air outside the room and condenses to become a high-pressure liquid refrigerant. The liquid refrigerant condensed in the heat source side heat exchanger 2 is reduced in pressure by passing through the expansion device 5 to become a low-pressure two-phase refrigerant. The low-pressure two-phase refrigerant flows into the user side heat exchanger 3 via the first extension pipe 113, where it exchanges heat with the air inside the room and evaporates to become a low-pressure gas refrigerant. The low-pressure gas refrigerant passes through the second extension pipe 114 and the flow switching device 4 and is drawn into the compressor 1.

[0042] In the heating operation mode, the first shutoff valve 6 and the second shutoff valve 7 are opened, and the flow path switching device 4 is set to the second state. In the heating operation mode, the user-side heat exchanger 3 functions as a condenser, and the heat-source-side heat exchanger 2 functions as an evaporator. The dashed arrows in Fig. 1 indicate the direction of refrigerant flow in the heating operation mode.

[0043] In the heating operation mode, the refrigerant flows sequentially through the compressor 1, the second shutoff valve 7, the second extension pipe 114, the user-side heat exchanger 3, the first extension pipe 113, the first shutoff valve 6, the expansion device 5, and the heat-source-side heat exchanger 2. Specifically, the high-pressure gas refrigerant discharged from the compressor 1 flows into the user-side heat exchanger 3 via the flow path switching device 4 and the second extension pipe 114, where it exchanges heat with the air inside the room and condenses to become a high-pressure liquid refrigerant. The liquid refrigerant condensed in the user-side heat exchanger 3 flows into the expansion device 5 via the first extension pipe 113, where it is decompressed by passing through the expansion device 5 to become a low-pressure two-phase refrigerant. The low-pressure two-phase refrigerant flows into the heat-source-side heat exchanger 2, where it exchanges heat with the air outside the room and evaporates to become a low-pressure gas refrigerant. The low-pressure gas refrigerant is drawn into the compressor 1 via the flow path switching device 4.

[0044] In the recovery operation mode, the first shutoff valve 6 is closed, the second shutoff valve 7 is opened, and the flow path switching device 4 is set to the first state. In the recovery operation mode, the heat source side heat exchanger 2 acts as a container for recovering refrigerant. In the recovery operation mode, the refrigerant is recovered in a portion of the heat source side refrigerant flow path 111 that is located between the discharge port of the compressor 1 and the first shutoff valve 6. In the recovery operation mode, in order to promote condensation of the refrigerant recovered in the heat source side heat exchanger 2, it is preferable that the heat source side fan for blowing air to the heat source side heat exchanger 2 described above continues to be driven.

[0045] When the refrigeration cycle apparatus 100 is operating in the cooling operation mode, if the control device 200 detects a refrigerant leak, only the first shutoff valve 6 is closed. The compressor 1 is kept operating at a predetermined frequency, the flow switching device 4 is maintained in the first state, and the second shutoff valve 7 is maintained in an open state.

[0046] When the control device 200 detects a refrigerant leak while the refrigeration cycle apparatus 100 is operating in the heating operation mode, the control device 200 controls each component of the refrigeration cycle apparatus 100 to start the recovery operation mode. The flow path switching device 4 is switched to the first state. The first shutoff valve 6 is closed. The compressor 1 is operated at a predetermined frequency. The second shutoff valve 7 is maintained in an open state.

[0047] The recovery operation mode is performed until the pressure in the user-side refrigerant flow path 112 falls below atmospheric pressure or until a predetermined time has elapsed since the start of the recovery operation mode. After the recovery operation mode ends, the compressor 1 stops and the second shutoff valve 7 is closed. At the end of the recovery operation mode, the refrigerant is recovered in a portion of the heat-source-side refrigerant flow path 111 that is located between the discharge port of the compressor 1 and the first shutoff valve 6. After the recovery operation mode ends and the replacement work for the piping or heat transfer tube where the refrigerant leaked has been completed, the compressor 1 is restarted and the first shutoff valve 6 and the second shutoff valve 7 are opened, allowing the refrigeration cycle apparatus 100 to resume normal operation.

[0048] In the refrigeration cycle device 100, to ensure that the recovery operation mode is performed reliably, the total internal volume of the heat source side heat exchanger 2 is set to be equal to or greater than the volume of the refrigerant in the refrigerant circuit 110 at the end of the recovery operation mode.

[0049] In the refrigeration cycle device 100, the total internal volume V of the heat source side heat exchanger 2 out (unit: m 3 ) are set so as to satisfy the following relational expression (1):

[0050]

[0051] In the above relational expression (1), V in (unit: m 3 ) is the total internal volume of the user-side heat exchanger 3, d L (unit: m) is the maximum inner diameter of the first extension pipe 113, d G (unit: m) is the maximum inner diameter of the second extension pipe 114, L (unit: m) is the maximum length of each of the first extension pipe 113 and the second extension pipe 114, ρ L (unit: kg / m 3 ) is the upper limit T of the ambient temperature of the refrigerant circuit at which the operation of the refrigeration cycle device is guaranteed. max The saturated liquid density of the refrigerant at the same temperature is ρ G (unit: kg / m 3 ) is the upper limit T max This shows the saturated gas density of the refrigerant at the same temperature.

[0052] The maximum length L of each of the first extension pipe 113 and the second extension pipe 114 means the maximum length of each of the first extension pipe 113 and the second extension pipe 114 specified in the above specifications when the length of each of the first extension pipe 113 and the second extension pipe 114 is adjustable. The maximum length L of each of the first extension pipe 113 and the second extension pipe 114 means the maximum length of each of the first extension pipe 113 and the second extension pipe 114 specified in the above specifications when the length of each of the first extension pipe 113 and the second extension pipe 114 is not adjustable.

[0053] The above relational expression (1) is derived as follows. First, the amount of refrigerant charged in the refrigerant circuit 110 of the refrigeration cycle apparatus 100 increases or decreases depending on the respective piping lengths of the first extension pipe 113 and the second extension pipe 114, and is maximum when the respective piping lengths of the first extension pipe 113 and the second extension pipe 114 are maximum value L. When the respective piping lengths of the first extension pipe 113 and the second extension pipe 114 are maximum value L, the refrigerant amount M ≠ ... ref (unit: kg) is estimated from the following experimentally derived relation (4).

[0054]

[0055] In the above relational expression (4), V in The term including V is the amount of refrigerant required to achieve the required heat exchange amount in the user side heat exchanger 3 in the normal operation mode. out The term including L indicates the amount of refrigerant required to achieve the required heat exchange amount in the heat source side heat exchanger 2 in the normal operation mode. The term including L indicates the amount of refrigerant flowing through each of the first extension pipe 113 and the second extension pipe 114, assuming that single-phase liquid refrigerant flows through the first extension pipe 113 and single-phase gas refrigerant flows through the second extension pipe 114 in the normal operation mode.

[0056] Second, the appropriate amount M of refrigerant recovered in the heat source side heat exchanger 2 in the recovery operation mode out (unit: kg) is the total internal volume V of the heat source side heat exchanger 2 outand is set so as to satisfy the following relational expression (5).

[0057]

[0058] In the above relational expression (5), the appropriate amount M out The left side showing the lower limit of the total internal volume V of the heat source side heat exchanger 2 out The optimum amount M is set from the viewpoint of suppressing a decline in performance due to an insufficient amount of refrigerant during normal operation caused by an excess of M, or from the viewpoint of eliminating the need to change the product specifications (for example, shorten the maximum piping length L) to suppress such a decline in performance. out The right side of the equation, which indicates the upper limit of the total internal volume V of the heat source side heat exchanger 2 required to retain the refrigerant inside the heat source side heat exchanger 2 in the recovery operation mode, is out is set as:

[0059] In order to properly perform the recovery operation mode, it is necessary that the heat source side heat exchanger 2 is able to recover the entire amount of refrigerant filled in the refrigerant circuit, that is, M ref = M out The above relational expression (1) is preferably M in the above relational expression (5). out to M in the above relational expression (4). ref is derived by substituting

[0060] <Effect> In the refrigeration cycle device 100, the total internal volume V of the heat source side heat exchanger 2 out (unit: m 3 ) are set so as to satisfy the above relational expression (1), so that the total internal volume V out In the refrigeration cycle apparatus 100, the total internal volume V of the heat source side heat exchanger 2 can be reduced compared to when V is larger than the right side of the relational expression (1). out (unit: m 3 ) are set so as to satisfy the above relational expression (1), so that the total internal volume V out is smaller than the left side of the relational expression (1) above, the heat source side heat exchanger 2 can recover a large amount of refrigerant, and the amount of refrigerant leakage can be reduced.

[0061] The total internal volume V of the heat source side heat exchanger 2 out (unit: m3 ) is provided so as to satisfy the above relational expression (1). Therefore, in the recovery operation mode, the gas refrigerant discharged from the compressor 1 flows into the heat source side heat exchanger 2, and the gas refrigerant can be sufficiently condensed in the heat source side heat exchanger 2.

[0062] In the refrigeration cycle device 100, the total internal volume V of the heat source side heat exchanger 2 out (unit: m 3 ) are provided so as to satisfy the above-mentioned relational expression (1), an accumulator and a receiver are not required from the viewpoint of reducing the amount of refrigerant leakage. Since the refrigerant circuit 110 of the refrigeration cycle apparatus 100 does not include an accumulator and a receiver, the amount of refrigerant charged in the refrigerant circuit 110 can be reduced compared to the amount of refrigerant charged in a refrigerant circuit that includes an accumulator and a receiver.

[0063] 1, the entire heat-source-side refrigerant flow path 111 is accommodated in a single heat-source-side unit 121. However, this is not limiting. For example, the compressor 1, the flow path switching device 4, and the expansion device 5 may be accommodated in a unit different from the heat-source-side heat exchanger 2.

[0064] In the refrigeration cycle apparatus 100, the refrigerant circuit 110 does not need to include the flow path switching device 4. In this case, it is sufficient that the discharge port of the compressor 1 is connected to the heat source side heat exchanger 2 and the suction port of the compressor 1 is connected to the user side heat exchanger 3. In other words, it is sufficient that the refrigeration cycle apparatus 100 is at least capable of switching between a cooling operation mode and a recovery operation mode.

[0065] 1, the control device 200 is included in the heat source side unit 121, but this is not limited to this. The control device 200 may be included in the user side unit 122, or the control device 200 may be divided so that a part of the control device 200 is included in the heat source side unit 121 and the rest of the control device 200 is included in the user side unit 122. Furthermore, the control device 200 may be disposed outside the heat source side unit 121 and the user side unit 122.

[0066] The expansion device 5 may be included in the user side unit 122 instead of the heat source side unit 121 .

[0067] The user side unit 122 may include at least one of a shut-off valve located near the connection between the user side refrigerant flow path 112 and the first extension pipe 113, and a shut-off valve located near the connection between the user side refrigerant flow path 112 and the second extension pipe 114.

[0068] 1 illustrates one heat source-side heat exchanger 2 and one user-side heat exchanger 3, the number of heat source-side heat exchangers 2 and the number of user-side heat exchangers 3 can be set arbitrarily. The refrigerant circuit 110 may include, for example, a plurality of heat source-side heat exchangers 2 connected in series with each other. In this case, the total internal volume V of the heat source-side heat exchangers 2 in the above relational expression (1) is out is the sum of the total internal volumes of the plurality of heat source side heat exchangers 2. The refrigerant circuit 110 may include, for example, a plurality of use side heat exchangers 3 connected to each other in series or in parallel. In this case, the total internal volume V of the use side heat exchangers 3 in the above relational expression (1) is in is the sum of the total internal volumes of the plurality of user-side heat exchangers 3.

[0069] 2 shows a refrigeration cycle apparatus 101 which is a modified example of the refrigeration cycle apparatus 100. As shown in Fig. 2, the refrigerant circuit 110 of the refrigeration cycle apparatus 101 does not have to include the first shutoff valve 6. In the refrigeration cycle apparatus 101, the expansion device 5 is controlled as a first control valve in the recovery operation mode in the same manner as the first shutoff valve 6 of the refrigeration cycle apparatus 100. In this case, the expansion device 5 is preferably disposed near the connection between the heat source side refrigerant flow path 111 and the first extension pipe 113.

[0070] Second Embodiment Unless otherwise specified, a refrigeration cycle apparatus 102 according to a second embodiment has the same configuration as the refrigeration cycle apparatus 100 according to the first embodiment, and exhibits the same effects.

[0071] As shown in FIG. 3 , in the refrigeration cycle apparatus 102 , the refrigerant circuit 110 further includes a first branch passage 116 , an on-off valve 8 , and a container 9 .

[0072] The heat source-side refrigerant flow path 111 includes a first refrigerant flow path connecting the heat source-side heat exchanger 2 and a first shutoff valve 6 serving as a first control valve. The first refrigerant flow path includes a third refrigerant flow path 115A connecting the heat source-side heat exchanger 2 and the expansion device 5, and a fourth refrigerant flow path 115B connecting the expansion device 5 and the first shutoff valve 6.

[0073] The first branched passage 116 branches off from the fourth refrigerant passage 115B, and only one end of the first branched passage 116 is connected to the fourth refrigerant passage 115B.

[0074] The on-off valve 8 opens and closes the first branch path 116. The on-off valve 8 is, for example, a solenoid valve or an electric valve. The opening and closing operation of the on-off valve 8 is controlled by, for example, the control device 200. Note that the on-off valve 8 may be configured to open in response to a physical factor such as a change in pressure or temperature of the refrigerant flowing through the first branch path 116.

[0075] The container 9 is connected to the fourth refrigerant flow path 115B via the first branch path 116 and the on-off valve 8. The internal pressure of the container 9 is set to be lower than the internal pressure of the refrigerant circuit 110 before shipping the refrigeration cycle apparatus 102.

[0076] The cooling operation mode, heating operation mode, and recovery operation mode of the refrigeration cycle apparatus 102 are performed in the same manner as those of the refrigeration cycle apparatus 100 .

[0077] The on-off valve 8 is closed in the normal operation mode. The container 9 is isolated from the refrigerant circuit 110 by the on-off valve 8 in the normal operation mode. The on-off valve 8 is opened in the recovery operation mode. The container 9 communicates with the refrigerant circuit 110 only in the recovery operation mode when the on-off valve 8 is open, and the refrigerant filled in the refrigerant circuit 110 can be recovered.

[0078] In the refrigeration cycle device 102, the total internal volume of the utilization side heat exchanger 3 is V in (unit: m 3 ), the maximum inner diameter of the first extension pipe 113 is d L (unit: m), the maximum inner diameter of the second extension pipe 114 is d G(unit: m), the maximum length of each of the first extension pipe 113 and the second extension pipe 114 is L (unit: m), and the upper limit value T of the ambient temperature of the refrigerant circuit 110 at which the operation of the refrigeration cycle device 102 is guaranteed. max The saturated liquid density of the refrigerant at the same temperature is ρ L (unit: kg / m 3 ), upper limit T max The saturated gas density of the refrigerant at the same temperature is ρ G (unit: kg / m 3 ) When the total internal volume V of the heat source side heat exchanger 2 is out (unit: m 3 ) and the internal volume V of the container 9 C is expressed by the following relational expression (2).

[0079]

[0080] The above relational expression (2) is derived from the above relational expressions (4) and (5), similarly to the above relational expression (1). In the refrigeration cycle device 102, since the container 9 is separated from the refrigerant circuit 110 in the normal operation mode, the appropriate amount M of refrigerant recovered in the heat source side heat exchanger 2 and the container 9 in the recovery operation mode is out (unit: kg) may be equal to or greater than the left side of the above relational expression (5), and there are no particular restrictions on the relationship with the right side of the above relational expression (5). Preferably, the appropriate amount M out (unit: kg) is equal to or less than the right side of the above relational expression (5). In other words, preferably, the total internal volume V out (unit: m 3 ) and the internal volume V of the container 9 C is expressed by the following relational expression (6).

[0081]

[0082] In the refrigeration cycle apparatus 102, the refrigerant circuit 110 includes a container 9, which is separated from the refrigerant circuit 110 in the normal operation mode but is connected to the refrigerant circuit 110 in the recovery operation mode. Therefore, in the refrigeration cycle apparatus 102, the amount of refrigerant recovered can be increased without increasing the amount of refrigerant charged.

[0083] Furthermore, the total internal volume V of the heat source side heat exchanger 2 out (unit: m 3 ) are set so as to satisfy the above relational expression (2), so that the total internal volume V out is smaller than the left side of the relational expression (2) above, the heat source side heat exchanger 2 can recover a large amount of refrigerant, and the amount of refrigerant leakage can be reduced.

[0084] In the refrigeration cycle device 102, the total internal volume V of the heat source side heat exchanger 2 out (unit: m 3 ) and the internal volume V of the container 9 ｃ and satisfies the above relational expression (2), it is possible to use a heat source side heat exchanger 2 having an even smaller total internal volume V than the refrigeration cycle apparatus 100.

[0085] <Modification> The first branched passage 116 may branch off from the third refrigerant passage 115A of the first refrigerant passage that connects the heat source side heat exchanger 2 and the expansion device 5 .

[0086] Fig. 4 shows a refrigeration cycle apparatus 103 which is a first modified example of the refrigeration cycle apparatus 102. As shown in Fig. 4, the refrigerant circuit 110 of the refrigeration cycle apparatus 103 does not have to include the first shutoff valve 6. In the refrigeration cycle apparatus 103, the expansion device 5 is controlled as a first control valve in the recovery operation mode in the same manner as the first shutoff valve 6 of the refrigeration cycle apparatuses 100 and 102. In the refrigeration cycle apparatus 103 as well, a first branch path 116 branches off from a first refrigerant flow path 115 which connects the heat source side heat exchanger 2 and the expansion device 5 which serves as the first control valve.

[0087] 5 shows a refrigeration cycle apparatus 104, which is a second modified example of the refrigeration cycle apparatus 102. As shown in FIG. 5, in the refrigeration cycle apparatus 104, a first branched passage 116 is connected in parallel with the first refrigerant flow path. One end and the other end of the first branched passage 116 are connected to the first refrigerant flow path. One end and the other end of the first branched passage 116 are connected to, for example, a fourth refrigerant flow path 115B.

[0088] In the refrigeration cycle apparatus 104, the container 9 is attached between one end and the other end of the first branch path 116. The heat source side refrigerant flow path 111 includes a first on-off valve 8a disposed between the container 9 and one end of the first branch path 116, and a second on-off valve 8b disposed between the container 9 and the other end of the first branch path 116.

[0089] The first on-off valve 8a and the second on-off valve 8b are each closed in the normal operation mode, and at least one of the first on-off valve 8a and the second on-off valve 8b is opened in the recovery operation mode.

[0090] In the refrigeration cycle apparatus 104, one end and the other end of the first branched path 116 may be connected to the third refrigerant flow path 115A. One end of the first branched path 116 may be connected to the third refrigerant flow path 115A, and the other end of the first branched path 116 may be connected to the fourth refrigerant flow path 115B.

[0091] The refrigeration cycle apparatuses 102 to 104 according to the second embodiment can be modified in the same manner as the refrigeration cycle apparatuses 100 and 101 according to the first embodiment.

[0092] Third Embodiment Unless otherwise specified, a refrigeration cycle apparatus 105 according to a third embodiment has the same configuration as the refrigeration cycle apparatus 100 according to the first embodiment, and exhibits the same effects.

[0093] As shown in FIG. 6 , in the refrigeration cycle apparatus 105 , the refrigerant circuit 110 further includes a second branch passage 118 , an on-off valve 8 , and a container 9 .

[0094] The heat source side refrigerant flow path 111 includes a second refrigerant flow path 117 that connects the compressor 1 and a second shutoff valve 7 serving as a second control valve. The second branch path 118 branches off from the second refrigerant flow path 117. The second branch path 118 branches off, for example, from a portion of the second refrigerant flow path 117 that connects the flow path switching device 4 and the second shutoff valve 7. Only one end of the second branch path 118 is connected to the second refrigerant flow path 117.

[0095] The on-off valve 8 opens and closes the second branch passage 118. The on-off valve 8 may have the same configuration as the on-off valve 8 described above.

[0096] The container 9 is connected to the second refrigerant flow path 117 via the second branch path 118 and the on-off valve 8. The internal pressure of the container 9 is set to be lower than the internal pressure of the refrigerant circuit 110 before shipping the refrigeration cycle apparatus 105.

[0097] The on-off valve 8 is closed in the normal operation mode. The container 9 is isolated from the refrigerant circuit 110 by the on-off valve 8 in the normal operation mode. The on-off valve 8 is opened in the recovery operation mode. The container 9 communicates with the refrigerant circuit 110 only in the recovery operation mode when the on-off valve 8 is open, and the refrigerant filled in the refrigerant circuit 110 can be recovered.

[0098] The cooling operation mode and the heating operation mode of the refrigeration cycle apparatus 105 are performed in the same manner as those of the refrigeration cycle apparatus 100 .

[0099] On the other hand, the recovery operation mode of the refrigeration cycle apparatus 105 is different from that of the refrigeration cycle apparatus 100 .

[0100] In the recovery operation mode, the second shutoff valve 7 is closed, the first shutoff valve 6 is opened, and the flow path switching device 4 is set to the second state. In the recovery operation mode, the container 9 acts as a container for recovering the refrigerant. In the recovery operation mode, the refrigerant is recovered in a portion of the heat source side refrigerant flow path 111 located between the discharge port of the compressor 1 and the second shutoff valve 7.

[0101] When the control device 200 detects a refrigerant leak while the refrigeration cycle device 105 is operating in the heating operation mode, only the second shutoff valve 7 is closed. The compressor 1 is kept operating at a predetermined frequency, the flow path switching device 4 is maintained in the second state, and the first shutoff valve 6 is maintained in an open state.

[0102] When the control device 200 detects a refrigerant leak while the refrigeration cycle device 105 is operating in the cooling operation mode, the control device 200 controls each component of the refrigeration cycle device 100 to start the recovery operation mode. The flow path switching device 4 is switched to the second state. The second shutoff valve 7 is closed. The compressor 1 is placed in a state of operating at a predetermined frequency. The first shutoff valve 6 is maintained in an open state. After the recovery operation mode ends, the compressor 1 is stopped and the first shutoff valve 6 is closed.

[0103] At the end of the recovery operation mode, the refrigerant is recovered in the heat source side refrigerant flow path 111 in a portion located between the discharge port of the compressor 1 and the second shutoff valve 7. In the refrigeration cycle device 105, the internal volume V of the container 9 is set to 0.5 V in order to ensure that the recovery is performed. c is set to be equal to or greater than the volume of refrigerant in the refrigerant circuit 110 at the end of the recovery operation mode.

[0104] In the refrigeration cycle device 105, the total internal volume of the utilization side heat exchanger 3 is V in (unit: m 3 ), the maximum inner diameter of the first extension pipe 113 is d L (unit: m), the maximum inner diameter of the second extension pipe 114 is d G (unit: m), the maximum length of each of the first extension pipe 113 and the second extension pipe 114 is L (unit: m), and the upper limit value T of the ambient temperature of the refrigerant circuit 110 at which the operation of the refrigeration cycle device 105 is guaranteed. max The saturated liquid density of the refrigerant at the same temperature is ρ L (unit: kg / m 3 ), upper limit T max The saturated gas density of the refrigerant at the same temperature is ρ G (unit: kg / m 3 ) when the internal volume V of the container 9 C is expressed by the following relational expression (3).

[0105]

[0106] The above relational expression (3) is derived as follows: The appropriate amount M of refrigerant recovered in the container 9 in the recovery operation mode c (unit: kg) is the internal volume V of the container 9 C and is set so as to satisfy the following relational expression (7).

[0107]

[0108] In the above relational expression (7), the appropriate amount M C The right side of the expression indicating the upper limit is set taking into consideration that a portion of the gas refrigerant recovered in the container 9 is likely to remain without being condensed.

[0109] In order to properly perform the recovery operation mode, it is necessary that the container 9 is capable of recovering the entire amount of refrigerant filled in the refrigerant circuit, i.e., M ref = M C The above relational expression (3) is preferably M in the above relational expression (7). C to M in the above relational expression (4). ref is derived by substituting

[0110] In the refrigeration cycle apparatus 105, the refrigerant circuit 110 includes a container 9, which is separated from the refrigerant circuit 110 in the normal operation mode but is connected to the refrigerant circuit 110 in the recovery operation mode. Therefore, in the refrigeration cycle apparatus 105, similar to the refrigeration cycle apparatus 102, the amount of refrigerant recovered can be increased without increasing the amount of refrigerant charged.

[0111] Furthermore, the internal volume V of the container 9 C (unit: m 3 ) is set to satisfy the above relational expression (3), so that the internal volume V C is smaller than the left side of the relational expression (3) above, the container 9 can recover a larger amount of refrigerant, and the amount of refrigerant leakage can be reduced.

[0112] <Modifications> In the refrigeration cycle apparatus 107, the container 9 is preferably arranged so that the refrigerant recovered therein exchanges heat with the air outside the container 9 or the refrigerant drawn into the compressor 1. Fig. 7 shows a refrigeration cycle apparatus 106 which is a first modification of the refrigeration cycle apparatus 105. The container 9 shown in Fig. 7 is arranged so that the refrigerant recovered therein exchanges heat with the refrigerant drawn into the compressor 1. This can promote condensation of the gas refrigerant discharged from the compressor 1 to the container 9 in the recovery operation mode. The container 9 may include fins that can come into contact with air circulating around the container 9.

[0113] 8 shows a refrigeration cycle apparatus 107 which is a second modified example of the refrigeration cycle apparatus 105. As shown in Fig. 8, in the refrigeration cycle apparatus 107, a second branched passage 118 is connected in parallel with a second refrigerant flow path 117. One end and the other end of the second branched passage 118 are connected to the second refrigerant flow path 117.

[0114] In the refrigeration cycle apparatus 107, the container 9 is attached between one end and the other end of the second branch path 118. The heat source side refrigerant flow path 111 includes a first on-off valve 8a disposed between the container 9 and one end of the second branch path 118, and a second on-off valve 8b disposed between the container 9 and the other end of the second branch path 118. Each of the first on-off valve 8a and the second on-off valve 8b is closed in the normal operation mode. At least one of the first on-off valve 8a and the second on-off valve 8b is opened in the recovery operation mode.

[0115] In the refrigeration cycle devices 105 to 107 as well, the refrigerant circuit 110 does not need to include the flow path switching device 4. In this case, it is sufficient that the discharge port of the compressor 1 is connected to the user-side heat exchanger 3 and the suction port of the compressor 1 is connected to the heat-source-side heat exchanger 2. In other words, it is sufficient that the refrigeration cycle devices 105 to 107 are at least switchable between a heating operation mode and a recovery operation mode.

[0116] The refrigeration cycle apparatuses 105 to 107 according to the third embodiment can be modified in the same manner as the refrigeration cycle apparatuses 100 and 101 according to the first embodiment or the refrigeration cycle apparatuses 102 and 103 according to the second embodiment.

[0117] Although the embodiments of the present disclosure have been described above, the above-described embodiments can be modified in various ways. Furthermore, the scope of the present disclosure is not limited to the above-described embodiments. The scope of the present disclosure is defined by the scope of the claims, and is intended to include all modifications within the meaning and scope of the claims.

[0118] REFRIGERATION CYCLE DEVICE, 100, 101, 102, 103, 104, 105, 106 REFRIGERATION CYCLE DEVICE, 110 REFRIGERATOR CIRCUIT, 111 HEAT SOURCE SIDE REFRIGERATOR PATH, 112 USE SIDE REFRIGERATOR PATH, 113 FIRST EXTENSION PIPE, 114 SECOND EXTENSION PIPE, 115 FIRST REFRIGERATOR PATH, 115A THIRD REFRIGERATOR PATH, 115B THIRD REFRIGERATOR PATH, 116 FIRST BRANCH, 117 SECOND REFRIGERATOR PATH, 118 SECOND BRANCH, 121 HEAT SOURCE SIDE UNIT, 122 USE SIDE UNIT, 200 CONTROL DEVICE, 201 PROCESSOR, 202 MEMORY, 300 SENSOR.

Claims

1. A refrigeration cycle device including a refrigerant circuit through which a refrigerant circulates, the refrigerant circuit including: a heat source side refrigerant flow path including a compressor and a heat source side heat exchanger; a utilization side refrigerant flow path including a utilization side heat exchanger; and a first extension pipe and a second extension pipe connecting the heat source side refrigerant flow path and the utilization side refrigerant flow path; and further including a control device for switching between a cooling operation mode and a recovery operation mode in which the refrigerant is recovered to the heat source side refrigerant flow path, in which in the cooling operation mode, the heat source side heat exchanger acts as a condenser and the utilization side heat exchanger acts as an evaporator, and the refrigerant flows through the compressor, the heat source side heat exchanger, the first extension pipe, the utilization side heat exchanger, and the second extension pipe in this order; the heat source side refrigerant flow path includes a first control valve disposed between the heat source side heat exchanger and the first extension pipe, and the first control valve is controlled to open in the cooling operation mode and to close in the recovery operation mode, and the total internal volume of the utilization side heat exchanger is V in (Unit: m 3 ), the maximum inner diameter of the first extension pipe is d L (unit: m), the maximum inner diameter of the second extension pipe is d G (unit: m), the maximum length of each of the first extension pipe and the second extension pipe is L (unit: m), and the upper limit value T of the ambient temperature of the refrigerant circuit at which the operation of the refrigeration cycle device is guaranteed. max The saturated liquid density of the refrigerant at the same temperature is ρ L (Unit: kg / m 3 ), the upper limit T max The saturated gas density of the refrigerant at the same temperature is ρ G (Unit: kg / m 3 ) When the total internal volume V of the heat source side heat exchanger is out (Unit: m 3 ) is expressed by the following relational expression (1).

2. The refrigeration cycle device according to claim 1, wherein the refrigerant circuit does not include an accumulator or a receiver.

3. A refrigeration cycle device as described in claim 1 or 2, wherein the first control valve is configured as an expansion valve that expands the refrigerant condensed in the heat source side heat exchanger in the cooling operation mode.

4. A refrigeration cycle device as described in claim 1 or 2, wherein the first control valve is configured as a shutoff valve that is fully opened in the cooling operation mode, and the refrigerant circuit further includes an expansion valve that expands the refrigerant condensed in the heat source side heat exchanger.

5. A refrigeration cycle device comprising a refrigerant circuit through which a refrigerant circulates, the refrigerant circuit comprising: a heat source side refrigerant flow path including a compressor and a heat source side heat exchanger; a utilization side refrigerant flow path including a utilization side heat exchanger; and a first extension pipe and a second extension pipe connecting the heat source side refrigerant flow path and the utilization side refrigerant flow path, and further comprising a control device for switching between a cooling operation mode and a recovery operation mode in which the refrigerant is recovered to the heat source side refrigerant flow path, wherein in the cooling operation mode, the heat source side heat exchanger acts as a condenser and the utilization side heat exchanger acts as an evaporator, and the refrigerant flows through the compressor, the heat source side heat exchanger, the first extension pipe, the utilization side heat exchanger, and the second extension pipe in that order, and the heat source side refrigerant flow path comprises: a first control valve disposed between the heat source side heat exchanger and the first extension pipe; The heat exchanger includes at least one on-off valve that opens and closes the first branch path, and a container that is connected to the first refrigerant flow path via the first branch path and the at least one on-off valve and is capable of recovering the refrigerant, the first control valve is controlled to open in the cooling operation mode and to close in the recovery operation mode, the at least one on-off valve is controlled to close in the cooling operation mode and to open in the recovery operation mode, and a total internal volume of the utilization side heat exchanger is V in (Unit: m 3 ), the maximum inner diameter of the first extension pipe is d L (unit: m), the maximum inner diameter of the second extension pipe is d G (unit: m), the maximum length of each of the first extension pipe and the second extension pipe is L (unit: m), and the upper limit value T of the ambient temperature of the refrigerant circuit at which the operation of the refrigeration cycle device is guaranteed. max The saturated liquid density of the refrigerant at the same temperature is ρ L (Unit: kg / m 3 ), the upper limit T max The saturated gas density of the refrigerant at the same temperature is ρ G (Unit: kg / m 3 ) When the total internal volume V of the heat source side heat exchanger is out (Unit: m 3 ) and the internal volume V of the container C is expressed by the following relational expression (2).

6. The total internal volume V of the heat source side heat exchanger out (Unit: m 3 ) and the internal volume V of the container C The refrigeration cycle apparatus according to claim 5 , wherein is expressed by the following relational expression (3).

7. A refrigeration cycle device as described in claim 5 or 6, wherein the first control valve is configured as an expansion valve that expands the refrigerant condensed in the heat source side heat exchanger in the cooling operation mode.

8. A refrigeration cycle apparatus as described in claim 5 or 6, wherein the first control valve is configured as a valve that is fully opened in the cooling operation mode, the refrigerant circuit further includes an expansion valve that expands the refrigerant condensed in the heat source side heat exchanger, and the first branch path branches off from a portion of the first refrigerant flow path that connects between the expansion valve and the first control valve.

9. A refrigeration cycle device according to any one of claims 5 to 8, wherein only one end of the first branch passage is connected to the first refrigerant flow passage.

10. A refrigeration cycle device as described in any one of claims 5 to 8, wherein the first branch path is connected in parallel with the first refrigerant flow path, and the at least one on-off valve includes a first on-off valve arranged between the container and one end of the first branch path, and a second on-off valve arranged between the container and the other end of the first branch path.

11. A refrigeration cycle apparatus according to any one of claims 1 to 10, wherein the heat source side refrigerant flow path further includes a switching device that is switched by the control device between a first state in which the discharge port of the compressor is connected to the heat source side heat exchanger and the suction port of the compressor is connected to the utilization side heat exchanger, and a second state in which the discharge port of the compressor is connected to the utilization side heat exchanger and the suction port of the compressor is connected to the heat source side heat exchanger, and the switching device is set to the first state in the cooling operation mode and the recovery operation mode.

12. A refrigeration cycle device comprising a refrigerant circuit through which a refrigerant circulates, the refrigerant circuit comprising: a heat source side refrigerant flow path including a compressor and a heat source side heat exchanger; a utilization side refrigerant flow path including a utilization side heat exchanger; and a first extension pipe and a second extension pipe connecting the heat source side refrigerant flow path and the utilization side refrigerant flow path, the device further comprising a control device for switching between a heating operation mode and a recovery operation mode in which the refrigerant is recovered to the heat source side refrigerant flow path, wherein in the heating operation mode, the utilization side heat exchanger acts as a condenser and the heat source side heat exchanger acts as an evaporator, and the refrigerant flows through the compressor, the second extension pipe, the utilization side heat exchanger, the first extension pipe, and the heat source side heat exchanger in that order, the heat source side refrigerant flow path comprising: a second control valve disposed between the second extension pipe and an intake port of the compressor; a second branch path branching off from the second refrigerant flow path connecting between the second control valve and the intake port; and at least one opening / closing valve for opening and closing the second branch path. a container connected to the second refrigerant flow path via the second branch path and the at least one on-off valve and capable of recovering the refrigerant, the second control valve being controlled to open in the heating operation mode and to close in the recovery operation mode, the at least one on-off valve being controlled to close in the heating operation mode and to open in the recovery operation mode, and a total internal volume of the utilization side heat exchanger is V in (Unit: m 3 ), the maximum inner diameter of the first extension pipe is d L (unit: m), the maximum inner diameter of the second extension pipe is d G (unit: m), the maximum length of each of the first extension pipe and the second extension pipe is L (unit: m), and the upper limit value T of the ambient temperature of the refrigerant circuit at which the operation of the refrigeration cycle device is guaranteed. max The saturated liquid density of the refrigerant at the same temperature is ρ L (Unit: kg / m 3 ), the upper limit T max The saturated gas density of the refrigerant at the same temperature is ρ G (Unit: kg / m 3 ) when the internal volume V of the container C is expressed by the following relational expression (4).

13. A refrigeration cycle device as described in claim 12, wherein the container is arranged so that the refrigerant recovered inside the container exchanges heat with the air outside the container or the refrigerant sucked into the compressor.

14. A refrigeration cycle device according to claim 12 or 13, wherein only one end of the second branch passage is connected to the second refrigerant flow passage.

15. A refrigeration cycle device as described in claim 12 or 13, wherein the second branch path is connected in parallel with the second refrigerant flow path, and the at least one on-off valve includes a first on-off valve arranged between the container and one end of the second branch path, and a second on-off valve arranged between the container and the other end of the second branch path.

16. A refrigeration cycle apparatus according to any one of claims 12 to 15, wherein the heat source side refrigerant flow path further includes a switching device that is switched by the control device between a first state in which the discharge port of the compressor is connected to the heat source side heat exchanger and the suction port of the compressor is connected to the utilization side heat exchanger, and a second state in which the discharge port of the compressor is connected to the utilization side heat exchanger and the suction port of the compressor is connected to the heat source side heat exchanger, and the switching device is set to the second state in the heating operation mode and the recovery operation mode.

17. A refrigeration cycle device according to any one of claims 1 to 16, wherein the refrigerant is a mixed refrigerant containing R32 and R1234yf, a mixed refrigerant containing R32 and R1123, a mixed refrigerant containing R32 and R1132(E), a mixed refrigerant containing R290 and R1123, a mixed refrigerant containing R290 and R1132(E), or R290.

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