WO2023135630A1

WO2023135630A1 - Air conditioner

Info

Publication number: WO2023135630A1
Application number: PCT/JP2022/000489
Authority: WO
Inventors: 良輔松井; 宗史池田
Original assignee: 三菱電機株式会社
Priority date: 2022-01-11
Filing date: 2022-01-11
Publication date: 2023-07-20
Also published as: JPWO2023135630A1

Abstract

This air conditioner comprises: a first heat load device having a first load-side heat exchanger that exchanges heat between a refrigerant and air in a target space and a first load-side expansion valve for expanding the refrigerant flowing into the first load-side heat exchanger or the refrigerant flowing out from the first load-side heat exchanger; a second heat load device having a second load-side heat exchanger that exchanges heat between a refrigerant and air in the target space and a second load-side expansion valve for expanding the refrigerant flowing into the second load-side heat exchanger or the refrigerant flowing out from the second load-side heat exchanger; a heat source machine that has a compressor for compressing the refrigerants and supplies the refrigerants to the first and second load-side heat exchangers; a refrigerant pipe through which the refrigerants flow therein and with which the first and second heat load devices are connected in parallel to the heat source machine; an electromagnetic valve that is provided to the refrigerant pipe and that adjusts the amount of the refrigerant flowing into the first heat load device or the refrigerant flowing out from the first heat load device; and a control device. The control device closes the first load-side expansion valve and the electromagnet valve and sets the opening of the second load-side expansion valve larger than the opening at present time when leakage of the refrigerant is detected in the first heat load device while leakage of the refrigerant is not detected in the second heat load device.

Description

air conditioner

The present disclosure relates to an air conditioner having a solenoid valve that cuts off the flow of refrigerant when refrigerant leaks.

Conventionally, there is an air conditioner that has a plurality of heat load devices connected in parallel to a heat source device, and that has solenoid valves that cut off the flow of refrigerant when refrigerant leaks, corresponding to each of the plurality of heat load devices. Are known. As such an example, Patent Document 1 discloses that, of two pipes connecting a heat source device and a plurality of heat load devices, one pipe is provided with the above-described solenoid valve, and the other pipe is provided with an expansion valve. An air conditioner provided is disclosed. The air conditioner of Patent Document 1 closes only the expansion valve and the solenoid valve corresponding to the heat load device in which refrigerant leakage has been detected, and cuts off the flow of refrigerant to the heat load device. The equipment continues to operate.

Japanese Patent No. 5517789

Generally, in air conditioners, including the air conditioner of Patent Document 1, when refrigerant leakage occurs, refrigerant leakage continues until the expansion valve is completely closed. Therefore, in the air conditioner, even when the flow of the refrigerant in the heat load device in which the refrigerant leakage is detected is cut off, the amount of refrigerant leakage is required to be reduced.

The present disclosure is intended to solve the above problems, and in an air conditioner having a plurality of heat load devices connected in parallel to a heat source device, when refrigerant leakage occurs on the heat load device side An object of the present invention is to provide an air conditioner that reduces the amount of refrigerant leakage.

The air conditioner according to the present disclosure includes a first load-side heat exchanger that exchanges heat between the air in the target space and the refrigerant, and the refrigerant flowing into the first load-side heat exchanger, or from the first load-side heat exchanger. Flows into a first heat load device having a first load-side expansion valve that expands the outflowing refrigerant, a second load-side heat exchanger that exchanges heat between the air in the target space and the refrigerant, and the second load-side heat exchanger. A second heat load device having a second load-side expansion valve for expanding the refrigerant flowing out of the second load-side heat exchanger or the refrigerant flowing out from the second load-side heat exchanger, a compressor for compressing the refrigerant, and a first load-side heat exchanger and a heat source device that supplies refrigerant to the second load side heat exchanger, a refrigerant pipe that flows inside and connects the first heat load device and the second heat load device in parallel to the heat source device; a solenoid valve provided in the refrigerant pipe for adjusting the amount of refrigerant flowing into the first heat load device or the amount of refrigerant flowing out of the first heat load device; When refrigerant leakage in the device is detected and refrigerant leakage in the second heat load device is not detected, the first load side expansion valve and the solenoid valve are closed, and the opening degree of the second load side expansion valve is increased. Increase the current opening.

In the air conditioner of the present disclosure, the load-side expansion valve and the solenoid valve corresponding to the heat load equipment in which refrigerant leakage has occurred are closed, and the opening degree of the expansion valve of the heat load equipment in which refrigerant leakage has not occurred is set to the current value. Enlarge more than opening. As a result, the amount of refrigerant supplied to the heat load equipment in which refrigerant leakage has not occurred increases, and the amount of refrigerant supplied to the heat load equipment in which refrigerant leakage has occurred decreases. Therefore, according to the present disclosure, in an air conditioner having a plurality of heat load devices connected in parallel to a heat source device, the amount of refrigerant leakage when refrigerant leakage occurs on the heat load device side is reduced. be able to.

1 is a circuit diagram of an air conditioner according to Embodiment 1. FIG. 4 is a diagram for explaining the cooling operation of the air conditioner according to Embodiment 1. FIG. 4 is a diagram for explaining the heating operation of the air conditioner according to Embodiment 1. FIG. 1 is a functional block diagram of an air conditioner according to Embodiment 1. FIG. 4 is a flow chart showing operations of the heat source side control device and the load side control device according to Embodiment 1. FIG. FIG. 4 is a diagram for explaining the control of the opening degree of the load-side expansion valve at the time of cooling leakage according to the first embodiment and the comparative example; FIG. 5 is a diagram for explaining cooling leakage amounts according to the first embodiment and a comparative example; FIG. 10 is a diagram for explaining control of the degree of opening of the heat source side expansion valve at the time of cooling leakage according to the second embodiment; FIG. 10 is a diagram for explaining cooling leakage amounts according to the second embodiment and a comparative example; FIG. 11 is a diagram for explaining cooling leakage amounts according to the third embodiment and a comparative example; FIG. 11 is a diagram for explaining cooling leakage amounts according to the fourth embodiment and a comparative example; FIG. 11 is a diagram for explaining cooling leakage amounts according to Embodiment 5 and a comparative example; FIG. 11 is a circuit diagram of an air conditioner according to Embodiment 6. FIG. FIG. 12 is a diagram for explaining the cooling operation of the air conditioner according to Embodiment 6; FIG. 12 is a diagram for explaining the heating operation of the air conditioner according to Embodiment 6;

Embodiments will be described below based on the drawings. In addition, in each figure, the same reference numerals denote the same or corresponding parts, and this is common throughout the specification. Also, the forms of the constituent elements shown in the entire specification are merely examples and are not limited to these descriptions. Furthermore, in the drawings below, the size relationship of each component may differ from the actual size.

Embodiment 1.
FIG. 1 is a circuit diagram of an air conditioner 100 according to Embodiment 1. FIG. The air conditioning apparatus 100 of Embodiment 1 air-conditions a plurality of target spaces such as a room in a building such as a building. As shown in FIG. 1, the air conditioner 100 includes a heat source device 1, a plurality of heat load devices 2a to 2c, and cutoff devices 3a to 3c. The heat load device 2a corresponds to the "first heat load device" of the present disclosure, and the heat load device 2b corresponds to the "second heat load device" of the present disclosure. Also, the number of heat load devices may be two or four or more.

The heat source unit 1 is, for example, an outdoor unit installed outside the target space. The heat load devices 2a to 2c of the air conditioner 100 supply heat or cold heat to the target space using the refrigerant supplied from the heat source device 1. FIG. The heat load devices 2a to 2c are, for example, indoor units that are installed in the target space and perform cooling or heating. The heat load devices 2a to 2c are connected to the heat source device 1 by

refrigerant pipes

4 and 5 through which refrigerant flows. The

refrigerant pipes

4 and 5 are branched to the heat load devices 2a to 2c, respectively. Therefore, the heat load devices 2a to 2c are connected in parallel to the heat source device 1. FIG.

The heat source device 1 includes a compressor 10, a flow path switching valve 11, a refrigerant heat exchanger 12, a heat source side expansion valve 13, an accumulator 14, a fan 15, a bypass valve 16, a heat source side refrigerant pipe 17, a bypass pipe 18, and a heat source side. A controller 19 is provided. The compressor 10 sucks a low-temperature, low-pressure gas refrigerant, compresses it, and discharges a high-temperature, high-pressure gas refrigerant. The compressor 10 is, for example, an inverter type compressor 10 whose capacity is controllable.

The channel switching valve 11 is, for example, a four-way valve. The channel switching valve 11 switches the channel of the refrigerant discharged from the compressor 10 according to the operation of the heat load devices 2a-2c. Although the details will be described later, the flow path switching valve 11 switches to the flow path indicated by the arrow in FIG. 2 during the cooling operation, and switches to the flow path indicated by the arrow in FIG. 3 during the heating operation. In addition, the channel switching valve 11 may be a combination of a three-way valve and a two-way valve.

The refrigerant heat exchanger 12 is, for example, a fin-tube heat exchanger. The refrigerant heat exchanger 12 exchanges heat between the air supplied by the fan 15 and the refrigerant. The refrigerant heat exchanger 12 functions as a condenser during cooling operation, and condenses and liquefies the refrigerant. Further, the refrigerant heat exchanger 12 functions as an evaporator during heating operation, and evaporates the refrigerant to gasify it. The heat source side expansion valve 13 is an electronic expansion valve whose opening degree is variably controlled. The heat source side expansion valve 13 is connected in series with the refrigerant heat exchanger 12 and reduces the pressure of the refrigerant flowing out of the refrigerant heat exchanger 12 or the refrigerant flowing into the refrigerant heat exchanger 12 to expand the refrigerant.

The accumulator 14 is provided on the suction side of the compressor 10 and has a function of separating liquid refrigerant and gas refrigerant and a function of storing excess refrigerant. Fan 15 is, for example, a propeller fan. The fan 15 supplies air around the heat source device 1 to the refrigerant heat exchanger 12 . The condensing ability or the evaporating ability of the refrigerant heat exchanger 12 is controlled by controlling the rotational speed of the fan 15 by the heat source side control device 19 . A bypass valve 16 is provided in a bypass pipe 18 . The bypass valve 16 adjusts the amount of refrigerant flowing through the bypass pipe 18 by having its opening controlled by the heat source side control device 19 .

The heat source side refrigerant pipe 17 is the pipe inside the housing (not shown) of the heat source device 1 among the pipes of the air conditioner 100 . The heat source side refrigerant pipe 17 connects the heat source side expansion valve 13, the refrigerant heat exchanger 12, the accumulator 14, the compressor 10, and the flow path switching valve 11 in this order. An end portion of the heat source side refrigerant pipe 17 on the flow path switching valve 11 side is connected to the refrigerant pipe 4 . Similarly, the heat source side expansion valve 13 side end of the heat source side refrigerant pipe 17 is connected to the refrigerant pipe 5 . The bypass pipe 18 is a pipe that connects the high pressure side and the low pressure side of the compressor 10 . Specifically, the bypass pipe 18 includes a heat source side refrigerant pipe 17 connected to the suction side of the compressor 10 and a heat source side refrigerant pipe 17 connected to the inflow side of the accumulator 14, that is, the discharge side of the compressor 10. to connect.

The heat source side control device 19 controls the operation of the compressor 10, the flow path switching valve 11, the heat source side expansion valve 13, the fan 15, and the bypass valve 16, which are connected by wire or wirelessly. The heat source side control device 19 is composed of a processing device including a memory for storing data and programs required for control and a CPU for executing the program, dedicated hardware such as ASIC or FPGA, or both. The heat source side control device 19 controls the drive frequency of the compressor 10, the flow path of the flow path switching valve 11, the opening degrees of the heat source side expansion valve 13 and the bypass valve 16, and the rotation speed of the fan 15 based on the detection results of each sensor. to control. Examples of sensors include a pressure sensor (not shown) mounted on the heat source device 1 for detecting refrigerant pressure and a temperature sensor (not shown) for detecting refrigerant temperature or outside air temperature.

In addition, the heat source side control device 19 can perform data communication with the load side control devices 25a to 25c (to be described later) of the heat load devices 2a to 2c connected by wire or wirelessly. Further, the heat source side control device 19 controls solenoid valves 31a to 31c, which are connected by wire or wirelessly and will be described later, of the blocking devices 3a to 3c when refrigerant leakage occurs. When refrigerant leakage occurs, the heat source side control device 19 indirectly controls the load side expansion valves 22a to 22c of the heat load devices 2a to 2c via the load side control devices 25a of the heat load devices 2a to 2c, which will be described later. to control. The control of these devices when refrigerant leakage occurs will be described later.

The heat load devices 2a to 2c supply the heat generated by the heat source device 1 to the cooling load or heating load of the target space. The heat load device 2a includes a load side heat exchanger 21a, a load side expansion valve 22a, a refrigerant leakage detection sensor 23a, a load side refrigerant pipe 24a, and a load side controller 25a. The load-side heat exchanger 21a is, for example, a fin-tube heat exchanger. The load-side heat exchanger 21a exchanges heat between the air in the target space and the refrigerant. The load-side heat exchanger 21a functions as a condenser during heating operation, and condenses and liquefies the refrigerant. In addition, the load-side heat exchanger 21a functions as an evaporator during cooling operation, and evaporates the refrigerant into gas.

The load-side expansion valve 22a is an electronic expansion valve whose opening degree is variably controlled. The load-side expansion valve 22a is connected in series with the load-side heat exchanger 21a, and decompresses and expands the refrigerant flowing out of the load-side heat exchanger 21a or the refrigerant flowing into the load-side heat exchanger 21a.

The refrigerant leakage detection sensor 23a is provided in a housing (not shown) of the heat load device 2a, and detects refrigerant leakage from the load side heat exchanger 21a, the load side expansion valve 22a, or the load side refrigerant pipe 24a. . Various conventionally used methods such as measurement of the refrigerant gas concentration in the housing or the pressure or temperature of the refrigerant flowing through the load-side refrigerant pipe 24a can be applied to the refrigerant leakage detection method itself. When the refrigerant leakage detection sensor 23a detects that refrigerant is leaking from the heat load device 2a, it transmits a detection signal indicating the fact to the load side control device 25a connected by wire or wirelessly.

The load-side refrigerant pipe 24a is, among the pipes of the air conditioner 100, the pipe inside the housing (not shown) of the heat load device 2a. The load-side refrigerant pipe 24a connects the load-side heat exchanger 21a and the load-side expansion valve 22a. The load-side heat exchanger 21 a side end of the load-side refrigerant pipe 24 a is connected to the refrigerant pipe 4 . Similarly, the load-side expansion valve 22 a side end of the load-side refrigerant pipe 24 a is connected to the refrigerant pipe 5 .

The load-side control device 25a controls the operation of the load-side expansion valve 22a connected by wire or wirelessly. The load-side control device 25a is composed of a processing device that includes a memory that stores data and programs required for control and a CPU that executes the program, dedicated hardware such as ASIC or FPGA, or both. The load-side control device 25a controls the load based on the detection results of a temperature sensor (not shown) that detects the temperature of the target space and a temperature sensor (not shown) that detects the temperature of the refrigerant at the outlet and inlet of the heat load device 2a. Controls the degree of opening of the side expansion valve 22a. A temperature sensor is, for example, a thermistor. Note that the load-side control device 25a controls the rotational speed of the opening of the load-side expansion valve 22a according to, for example, the difference between the temperature of the target space and the target temperature.

Also, when the load-side control device 25 a receives a detection signal indicating that the refrigerant is leaking from the refrigerant leakage detection sensor 23 a, it transmits a leakage occurrence signal to the heat source-side control device 19 . In addition, the load-side control device 25a closes the load-side expansion valve 22a substantially at the same time. The leakage occurrence signal includes information indicating in which heat load device leakage of the refrigerant has occurred. The refrigerant leakage detection sensor 23a may have only the function of transmitting the result of measuring the refrigerant gas concentration in the housing or the pressure or temperature of the refrigerant flowing through the load-side refrigerant pipe 24a to the load-side control device 25a. . In this case, the load-side control device 25a determines whether or not the refrigerant is leaking based on the measurement result of the refrigerant leakage detection sensor 23a.

The

heat load devices

2b and 2c have the same configuration as the heat load device 2a. That is, the heat load device 2b includes a load side heat exchanger 21b, a load side expansion valve 22b, a refrigerant leakage detection sensor 23b, a load side refrigerant pipe 24b, and a load side control device 25b. Similarly, the heat load device 2c includes a load side heat exchanger 21c, a load side expansion valve 22c, a refrigerant leakage detection sensor 23c, a load side refrigerant pipe 24c, and a load side control device 25c. The configuration of each device included in the

heat load devices

2b and 2c is also the same as that of the heat load device 2a, so description thereof will be omitted. The load-side heat exchanger 21a corresponds to the "first load-side heat exchanger" of the present disclosure, and the load-side heat exchanger 21b corresponds to the "second load-side heat exchanger" of the present disclosure. Further, the load-side expansion valve 22a corresponds to the "first load-side expansion valve" of the present disclosure, and the load-side expansion valve 22b corresponds to the "second load-side expansion valve" of the present disclosure.

The heat source side expansion valve 13, the refrigerant heat exchanger 12, the accumulator 14, the compressor 10, and the flow path switching valve 11 of the heat source device 1, and the load side heat exchangers 21a to 21c and the load A refrigerant circuit 6 is configured by connecting the side expansion valves 22a to 22c and the solenoid valves 31a to 31c by the heat source side refrigerant pipe 17 and the load side refrigerant pipes 24a to 24c.

The shutoff device 3a has an electromagnetic valve 31a. The solenoid valve 31a is provided at a branched portion of the refrigerant pipe 4 at a position corresponding to the heat load device 2a. The electromagnetic valve 31a is housed in a housing (not shown) of the cutoff device 3a. The solenoid valve 31a adjusts the flow rate of refrigerant flowing through the heat load device 2a. The solenoid valve 31a is controlled to be closed by the heat source side control device 19 when refrigerant leakage occurs from the heat load device 2a, and the flow of the refrigerant in the heat load device 2a, that is, the inflow of the refrigerant into the heat load device 2a, and block the outflow of the refrigerant from the heat load device 2a.

The

blocking devices

3b and 3c have the same configuration as the blocking device 3a. In other words, the cutoff device 3b includes an electromagnetic valve 31b corresponding to the heat load device 2b. Similarly, the cutoff device 3c includes an electromagnetic valve 31c corresponding to the heat load device 2c.

The air conditioner 100 performs cooling operation or heating operation based on instructions from a remote controller (not shown) or the like for the heat load devices 2a to 2c. Cooling operation and heating operation are realized by switching the channel switching valve 11 of the heat source device 1 . The refrigerant flow in each operation will be described below. FIG. 2 is a diagram for explaining the cooling operation of the air conditioner 100 according to Embodiment 1. FIG. As shown in FIG. 2 , in cooling operation, high-temperature and high-pressure gas refrigerant discharged from the compressor 10 flows through the flow path switching valve 11 into the refrigerant heat exchanger 12 . The refrigerant that has flowed into the refrigerant heat exchanger 12 exchanges heat with the air supplied by the fan 15, condenses, and liquefies. The refrigerant flowing out of the refrigerant heat exchanger 12 passes through the refrigerant pipe 5 and is split to the heat load devices 2a to 2c.

The refrigerant that has flowed into the heat load devices 2a-2c is depressurized by the load-side expansion valves 22a-22c, becomes a low-temperature gas-liquid two-phase refrigerant, and flows into the load-side heat exchangers 21a-21c. The refrigerant that has flowed into the load-side heat exchangers 21a to 21c exchanges heat with the air in the target space, evaporates, and gasifies. At this time, the refrigerant absorbs heat from the air in the target space, thereby cooling the target spaces in which the heat load devices 2a to 2c are installed. The refrigerant flowing out of the load-side heat exchanger 21 a flows into the heat source device 1 through the refrigerant pipe 4 . The refrigerant that has flowed into the heat source device 1 is sucked into the compressor 10 again via the flow path switching valve 11 and the accumulator 14 .

FIG. 3 is a diagram for explaining the heating operation of the air conditioner 100 according to Embodiment 1. FIG. As shown in FIG. 3, in the heating operation, the high-temperature and high-pressure gas refrigerant discharged from the compressor 10 flows out from the heat source device 1 through the flow path switching valve 11, and flows through the refrigerant pipe 4 to the heat load equipment. 2a to 2c. The refrigerant that has flowed into the heat load devices 2a-2c exchanges heat with the air in the target space in the load-side heat exchangers 21a-21c, condenses, and liquefies. At this time, the refrigerant dissipates heat to the air in the target space, thereby heating the target spaces in which the heat load devices 2a to 2c are installed. The refrigerant flowing out of the load-side heat exchangers 21a-21c is decompressed by the load-side expansion valves 22a-22c, flows out of the heat load devices 2a-2c, and flows through the refrigerant pipe 5 into the heat source device 1.

The refrigerant that has flowed into the heat source device 1 flows into the refrigerant heat exchanger 12 . The refrigerant that has flowed into the refrigerant heat exchanger 12 exchanges heat with the air supplied by the fan 15 to evaporate and gasify. The refrigerant that has flowed out of the refrigerant heat exchanger 12 is sucked into the compressor 10 again via the flow switching valve 11 and the accumulator 14 .

Here, the details of the control of the load-side expansion valves 22a-22c of the thermal load devices 2a-2c and the electromagnetic valves 31a-31c of the blocking devices 3a-3c by the heat source-side control device 19 and the load-side control devices 25a-25c will be described. do. FIG. 4 is a functional block diagram of the air conditioner 100 according to Embodiment 1. As shown in FIG. As shown in FIG. 4, when the refrigerant leakage detection sensors 23a to 23c detect that refrigerant is leaking from the corresponding heat load devices 2a to 2c, the detection signals to that effect are sent to the corresponding load side. It is transmitted to the control devices 25a to 25c. The load-side control devices 25a-25c receive detection signals from the refrigerant leakage detection sensors 23a-23c. The load-side control devices 25a to 25c transmit a leak occurrence signal to the heat source-side control device 19 upon receiving the detection signal. Also, the load-side control devices 25a-25c close the corresponding load-side expansion valves 22a-22c. In addition, the load-side control devices 25aa-25c in which no refrigerant leakage has occurred expand the opening degrees of the load-side expansion valves 22a-22c based on the command from the heat source-side control device 19 from the current opening degrees.

When the heat source side control device 19 receives a leakage occurrence signal from one of the load side control devices 25a to 25c, the heat source side control device 19 closes the electromagnetic valves 31a to 31c corresponding to the heat load devices 2a to 2c in which refrigerant leakage is occurring. . Then, the heat source side control device 19 increases the opening degrees of the load side expansion valves 22a to 22c of the heat load devices 2a to 2c in which refrigerant leakage does not occur. 25a-25c. Specifically, the heat source side control device 19 fully opens the load side expansion valves 22a to 22c when they are not fully open, and maintains the fully opened state when the load side expansion valves 22a to 22c are already fully open.

Here, the order of operation of the heat source side control device 19 and the load side control devices 25a to 25c will be described. FIG. 5 is a flow chart showing operations of the heat source side control device 19 and the load side control devices 25a to 25c according to the first embodiment. In FIG. 5, the left column shows the processing contents of the heat source side control device 19, the middle column shows the processing contents of the load side control device 25a, and the right column shows the processing contents of the load side control devices 25b and 25c. is shown. In the following, for the sake of simplicity, a case will be exemplified where refrigerant leakage occurs in the heat load device 2a and refrigerant leakage does not occur in the

heat load devices

2b and 2c. In addition, the load side expansion valves 22a to 22c of the thermal load devices 2a to 2c and the solenoid valves 31a to 31c of the shutoff devices 3a to 3c are all kept open until the leakage of the refrigerant is detected. will be described as a premise. However, the load-side expansion valves 22a to 22c are opened at an opening degree less than fully open.

As shown in FIG. 5, first, when the refrigerant leakage detection sensor 23a detects that refrigerant is leaking from the heat load device 2a, the load-side control device 25a receives a signal from the refrigerant leakage detection sensor 23a. A detection signal is received (step S1). Upon receiving the detection signal, the load side control device 25a transmits a leakage occurrence signal to the heat source side control device 19 (step S2). Then, the load-side control device 25a closes the load-side expansion valve 22a (step S3).

When the heat source side control device 19 receives the leakage occurrence signal from the load side control device 25a, it closes the electromagnetic valve 31a corresponding to the heat load device 2a in which the refrigerant is leaking (step S4). Then, the heat source side control device 19 increases the opening degrees of the load

side expansion valves

22b and 22c of the

heat load devices

2b and 2c in which refrigerant leakage is not occurring. 25b and 25c (step S5). The load-

side control devices

25b and 25c that have received the command from the heat source-side control device 19 increase the opening degrees of the load-

side expansion valves

22b and 22c from the current opening degrees (step S6). Note that step S2 and step S3 may be interchanged.

Thus, in Embodiment 1, the load side expansion valves 22a to 22c and the electromagnetic valves 31a to 31c corresponding to the heat load devices 2a to 2c in which refrigerant leakage has occurred are closed. Along with this control, the opening degrees of the load side expansion valves 22a to 22c of the heat load devices 2a to 2c in which no refrigerant leakage has occurred are increased. The case where refrigerant leakage occurs in the heat load device 2a and refrigerant leakage does not occur in the

heat load devices

2b and 2c has been exemplified. However, the control of the load

side expansion valve

22b or 22c and the

electromagnetic valve

31b or 31c is the same when refrigerant leakage occurs in the

heat load device

2b or 2c. That is, for example, when refrigerant leakage occurs in the heat load device 2b and refrigerant leakage does not occur in the

heat load devices

2a and 2c, the load side expansion valve 22b and the electromagnetic valve 31b are closed, and the load side expansion valve 22b and the solenoid valve 31b are closed. The opening degrees of the

valves

22a and 22c are increased from the current opening degrees. Further, when refrigerant leakage occurs in the

heat load devices

2a and 2b and no refrigerant leakage occurs in the heat load device 2c, the load

side expansion valves

22a and 22b and the

solenoid valves

31a and 31b are closed, The opening of the load-side expansion valve 22c is increased from the current opening.

The effects obtained by Embodiment 1 will be described below by comparing Embodiment 1 and a comparative example. FIG. 6 is a diagram for explaining control of the opening degree of the load-side expansion valve at the time of cooling leakage according to the first embodiment and the comparative example. In FIG. 6, the opening degrees [pulse] of the load-side expansion valves 22a to 22c of the heat load devices 2a to 2c in which the refrigerant leakage is detected according to Embodiment 1 are plotted against the elapsed time after the refrigerant leakage is detected. Each [s] is indicated by a white triangle. Similarly, the load-side expansion valves 22a to 22c of the thermal load devices 2a to 2c, in which leakage of the refrigerant is not detected according to Embodiment 1, that is, are normal, are indicated by black triangles. In addition, the load-side expansion valve of the heat load device in which leakage of the refrigerant according to the comparative example was detected is indicated by an outline circle. The load-side expansion valves of the normal thermal load equipment according to the comparative example are indicated by black circles.

As shown in FIG. 6, the air conditioner 100 of Embodiment 1 closes the load-side expansion valves 22a to 22c and solenoid valves 31a to 31c corresponding to the heat load devices 2a to 2c in which refrigerant leakage has occurred. Further, the air conditioner 100 of Embodiment 1 expands the opening degrees of the load-side expansion valves 22a to 22c of the heat load devices 2a to 2c in which refrigerant leakage does not occur from the current opening degrees. On the other hand, the comparative example has a configuration equivalent to that of the air conditioner 100 of Embodiment 1, but differs in control content. That is, in the comparative example, although the load-side expansion valve and solenoid valve corresponding to the heat-load equipment in which refrigerant leakage has occurred are closed, the opening degree of the load-side expansion valve of the heat-load equipment in which refrigerant leakage has not occurred is less than fully open. to maintain a constant degree of opening.

FIG. 7 is a diagram for explaining cooling leakage amounts according to the first embodiment and the comparative example. In FIG. 7, the refrigerant leakage amount QI [g/s] according to Embodiment 1 is indicated by black triangles for each elapsed time [s] after the refrigerant leakage is detected. Similarly, the refrigerant leakage amount QI [g/s] according to the comparative example is indicated by black circles. In the air conditioner according to the comparative example, when closing the load-side expansion valve of the heat-load equipment in which refrigerant leakage has been detected, the opening degree of the load-side expansion valve of the heat-load equipment in which refrigerant leakage has not been detected is constant. Therefore, the total flow area of all heat load devices is narrowed. Therefore, in the process of closing the load-side expansion valve of the heat-load device in which refrigerant leakage has been detected, the pressure at the inlet of the load-side expansion valve of each heat-load device increases. At this time, the pressure difference between the inlet and outlet of the load-side expansion valve of each heat load device increases, and the amount of refrigerant passing through the load-side expansion valve of the heat load device in which refrigerant leakage has been detected also increases. The amount of refrigerant leakage until the valve is fully closed is greater than in the first embodiment.

On the other hand, in Embodiment 1, the load-side expansion valves 22a to 22c and solenoid valves 31a to 31c corresponding to the heat load devices 2a to 2c in which refrigerant leakage has occurred are closed, and the heat load devices in which refrigerant leakage has not occurred are closed. The opening degrees of the load side expansion valves 22a to 22c of 2a to 2c are increased. As a result, the total flow area of all the heat load devices 2a to 2c is kept constant. Therefore, the pressure at the inlets of the load-side expansion valves 22a-22c does not rise. Therefore, in the process of closing the load-side expansion valves 22a to 22c of the heat load devices 2a to 2c in which refrigerant leakage has been detected, only the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has not occurred is reduced. The amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has occurred decreases. Therefore, in Embodiment 1, the amount of refrigerant leakage can be reduced until the load-side expansion valves 22a to 22c corresponding to the heat load devices 2a to 2c in which refrigerant leakage has occurred are fully closed.

As described above, in Embodiment 1, the load-side expansion valves 22a to 22c and solenoid valves 31a to 31c corresponding to the heat load devices 2a to 2c in which refrigerant leakage has occurred are closed, and no refrigerant leakage has occurred. The opening degrees of the load side expansion valves 22a to 22c of the heat load devices 2a to 2c are increased from the current opening degrees. As a result, the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has not occurred increases, and the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has occurred decreases. Therefore, according to Embodiment 1, in the air conditioner 100 having a plurality of heat load devices 2a to 2c connected in parallel to the heat source device 1, refrigerant leakage occurs on the side of the heat load devices 2a to 2c. It is possible to reduce the amount of refrigerant leakage at the time of occurrence.

Further, according to Embodiment 1, in order to cut off the flow of refrigerant to the heat load devices 2a to 2c in which refrigerant leakage has occurred, the heat load devices 2a to 2c in which refrigerant leakage has not occurred continue to operate. It is possible to Therefore, it is possible to prevent the comfort of the target space in which the heat load devices 2a to 2c are installed from being impaired.

In the first embodiment, when refrigerant leakage occurs, the opening degrees of the load-side expansion valves 22a to 22c of all the heat load devices 2a to 2c in which no refrigerant leakage has occurred are increased from the current opening degrees. I explained it as a thing to do. However, if the total flow area of all the heat load devices 2a to 2c is maintained constant, any one of the load side expansion valves 22a to 22c of the heat load devices 2a to 2c in which refrigerant leakage does not occur The opening degrees of the load side expansion valves 22a to 22c may be increased.

Embodiment 2.
Embodiment 2 differs from Embodiment 1 in that the degree of opening of the heat source side expansion valve 13 is made smaller than the current degree of opening when refrigerant leakage is detected in any of the heat load devices 2a to 2c. differ. In the second embodiment, the same reference numerals are assigned to the same parts as in the first embodiment, and the description thereof is omitted.

The air conditioner 100 of Embodiment 2 has the same configuration as the air conditioner 100 of Embodiment 1. Below, the effects obtained by the second embodiment will be described by comparing the second embodiment with a comparative example. FIG. 8 is a diagram for explaining control of the degree of opening of the heat source side expansion valve 13 at the time of cooling leakage according to the second embodiment. In FIG. 8, the opening degree [pulse] of the heat source side expansion valve 13 of the heat source device 1 in which refrigerant leakage is detected according to Embodiment 2 is changed for each elapsed time [s] after the refrigerant leakage is detected. It is indicated by a white circle. Since the configuration and control details of the air conditioner in the comparative example are the same as those described in Embodiment 1, detailed description thereof will be omitted. As shown in FIG. 8, the heat-source-side control device 19 of the second embodiment operates when refrigerant leakage is detected in any of the heat load devices 2a to 2c during cooling operation, as described in the first embodiment. In addition to the above control, the degree of opening of the heat source side expansion valve 13 is made smaller than it is at present.

FIG. 9 is a diagram for explaining cooling leakage amounts according to the second embodiment and the comparative example. In FIG. 9, the refrigerant leakage amount QI [g/s] according to Embodiment 2 is indicated by black squares for each elapsed time [s] after the refrigerant leakage is detected. Similarly, the refrigerant leakage amount QI [g/s] according to the comparative example is indicated by black circles. In the comparative example, when the opening degree of the heat source side expansion valve 13 of the heat source device 1 is fully open, the refrigerant at the inlets of the load side expansion valves 22a to 22c is in the liquid phase.

On the other hand, in Embodiment 2, when the opening degree of the heat source side expansion valve 13 of the heat source device 1 is reduced, the refrigerant at the inlets of the load side expansion valves 22a to 22c is two-phase. Since the density of the two-phase refrigerant is lower than that of the liquid phase, even if the volume of the refrigerant passing through the load-side expansion valves 22a to 22c with a certain degree of opening is the same, the weight of the refrigerant is higher than that of the two-phase refrigerant. is smaller than the liquid phase. Therefore, in the second embodiment, the amount of refrigerant that leaks can be reduced more than in the comparative example.

The order of operation of the heat source side control device 19 and the load side control devices 25a to 25c of the second embodiment is that after any of steps S2 to S6 described in the first embodiment, the heat source side control device 19 controls the heat source side. This corresponds to addition of a process to make the opening of the expansion valve 13 smaller than the current opening. Therefore, detailed description is omitted.

As described above, in the second embodiment, the load-side expansion valves 22a to 22c and solenoid valves 31a to 31c corresponding to the heat load devices 2a to 2c in which refrigerant leakage has occurred are closed, and no refrigerant leakage has occurred. The opening degrees of the load side expansion valves 22a to 22c of the heat load devices 2a to 2c are increased from the current opening degrees. As a result, the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has not occurred increases, and the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has occurred decreases. Therefore, according to Embodiment 2, in the air conditioner 100 having a plurality of heat load devices 2a to 2c connected in parallel to the heat source device 1, refrigerant leakage occurs on the side of the heat load devices 2a to 2c. It is possible to reduce the amount of refrigerant leakage at the time of occurrence.

Further, according to Embodiment 2, since the flow of refrigerant to the heat load devices 2a to 2c in which refrigerant leakage has occurred is blocked, the operation of the heat load devices 2a to 2c in which refrigerant leakage has not occurred continues. It is possible to Therefore, it is possible to prevent the comfort of the target space in which the heat load devices 2a to 2c are installed from being impaired.

Further, according to the second embodiment, when refrigerant leakage is detected in any one of the heat load devices 2a to 2c, the degree of opening of the heat source side expansion valve 13 is made smaller than the current degree of opening. The refrigerant at the inlets of the side expansion valves 22a-22c can be two-phase. As a result, the density of the refrigerant is reduced, so that the amount of refrigerant leakage can be further reduced.

Embodiment 3.
Embodiment 3 differs from Embodiment 1 in that the air volume of fan 15 is reduced from the current air volume when refrigerant leakage is detected in any of heat load devices 2a to 2c. In the third embodiment, the same reference numerals are assigned to the same parts as in the first embodiment, and the description thereof is omitted.

The air conditioner 100 of Embodiment 3 has the same configuration as the air conditioner 100 of Embodiment 1. Below, the effects obtained by the third embodiment will be described by comparing the third embodiment and a comparative example. In addition to the control described in Embodiment 1, the heat source side control device 19 of Embodiment 3 operates when refrigerant leakage is detected in any of the heat load devices 2a to 2c during cooling operation. to lower the current airflow. Since the configuration and control details of the air conditioner in the comparative example are the same as those described in Embodiment 1, detailed description thereof will be omitted.

FIG. 10 is a diagram for explaining cooling leakage amounts according to the third embodiment and the comparative example. In FIG. 10, the refrigerant leakage amount QI [g/s] according to Embodiment 3 is indicated by black diamonds for each elapsed time [s] after the refrigerant leakage is detected. Similarly, the refrigerant leakage amount QI [g/s] according to the comparative example is indicated by black circles. In Embodiment 3, by reducing the air volume of the fan 15 from the current air volume, the degree of subcooling of the refrigerant flowing through the outlet of the refrigerant heat exchanger 12 is reduced, and the density of the refrigerant is reduced. By reducing the density of the refrigerant, the weight of the refrigerant becomes smaller even if the volume of the refrigerant passing through the load-side expansion valves 22a to 22c with a certain degree of opening remains the same. Therefore, as shown in FIG. 10, in the third embodiment, the amount of refrigerant that leaks can be reduced more than in the comparative example.

The order of operation of the heat source side control device 19 and the load side control devices 25a to 25c of the third embodiment is that the fan 15 is operated by the heat source side control device 19 after any of steps S2 to S6 described in the first embodiment. This corresponds to the addition of processing to lower the current air volume below the current air volume. Therefore, detailed description is omitted.

As described above, in the third embodiment, the load-side expansion valves 22a to 22c and solenoid valves 31a to 31c corresponding to the heat load devices 2a to 2c in which refrigerant leakage has occurred are closed, and no refrigerant leakage has occurred. The opening degrees of the load side expansion valves 22a to 22c of the heat load devices 2a to 2c are increased from the current opening degrees. As a result, the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has not occurred increases, and the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has occurred decreases. Therefore, according to Embodiment 3, in the air conditioner 100 having a plurality of heat load devices 2a to 2c connected in parallel to the heat source device 1, refrigerant leakage occurs on the side of the heat load devices 2a to 2c. It is possible to reduce the amount of refrigerant leakage at the time of occurrence.

Further, according to the third embodiment, since the flow of refrigerant to the heat load devices 2a to 2c in which refrigerant leakage has occurred is blocked, the heat load devices 2a to 2c in which refrigerant leakage has not occurred continue to operate. It is possible to Therefore, it is possible to prevent the comfort of the target space in which the heat load devices 2a to 2c are installed from being impaired.

Further, according to the third embodiment, when refrigerant leakage is detected in any of the heat load devices 2a to 2c, the air volume of the fan 15 is reduced below the current air volume. The degree of subcooling of the refrigerant flowing through the outlet is reduced. As a result, the density of the refrigerant is reduced, so that the amount of refrigerant leakage can be further reduced.

Embodiment 4.
The fourth embodiment differs from the first embodiment in that the bypass valve 16 is opened when refrigerant leakage is detected in any one of the heat load devices 2a to 2c. In the fourth embodiment, the same reference numerals are assigned to the same parts as in the first embodiment, and the description thereof is omitted.

The air conditioner 100 of Embodiment 4 has the same configuration as the air conditioner 100 of Embodiment 1. Below, the effect obtained by Embodiment 4 is demonstrated by comparing Embodiment 4 and a comparative example. The heat source side control device 19 of the fourth embodiment opens the bypass valve 16 in addition to the control described in the first embodiment when refrigerant leakage is detected in any one of the heat load devices 2a to 2c. Since the configuration and control details of the air conditioner in the comparative example are the same as those described in Embodiment 1, detailed description thereof will be omitted.

FIG. 11 is a diagram for explaining cooling leakage amounts according to the fourth embodiment and the comparative example. In FIG. 11, the refrigerant leakage amount QI [g/s] according to Embodiment 4 is indicated by white triangles for each elapsed time [s] after the refrigerant leakage is detected. Similarly, the refrigerant leakage amount QI [g/s] according to the comparative example is indicated by black circles. In the fourth embodiment, by opening the bypass valve 16, the discharge pressure of the compressor 10 decreases and the suction pressure of the compressor 10 increases. As a result, the pressure difference between the inlets and outlets of the load-side expansion valves 22a to 22c is reduced. Therefore, the amount of refrigerant passing through the load-side expansion valves 22a to 22c of the heat load devices 2a to 2c for which refrigerant leakage has been detected decreases. Therefore, as shown in FIG. 11, in the fourth embodiment, the amount of refrigerant that leaks can be reduced more than in the comparative example.

The order of operation of the heat source side control device 19 and the load side control devices 25a to 25c of the fourth embodiment is that after any of steps S2 to S6 described in the first embodiment, the heat source side control device 19 turns the bypass valve on. 16 is added. Therefore, detailed description is omitted.

As described above, in the fourth embodiment, the load-side expansion valves 22a to 22c and solenoid valves 31a to 31c corresponding to the heat load devices 2a to 2c in which refrigerant leakage has occurred are closed, and no refrigerant leakage has occurred. The opening degrees of the load side expansion valves 22a to 22c of the heat load devices 2a to 2c are increased from the current opening degrees. As a result, the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has not occurred increases, and the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has occurred decreases. Therefore, according to Embodiment 4, in the air conditioner 100 having a plurality of heat load devices 2a to 2c connected in parallel to the heat source device 1, refrigerant leakage occurs on the side of the heat load devices 2a to 2c. It is possible to reduce the amount of refrigerant leakage at the time of occurrence.

Further, according to the fourth embodiment, in order to cut off the flow of refrigerant to the heat load devices 2a to 2c in which refrigerant leakage has occurred, the heat load devices 2a to 2c in which refrigerant leakage has not occurred continue to operate. It is possible to Therefore, it is possible to prevent the comfort of the target space in which the heat load devices 2a to 2c are installed from being impaired.

Further, according to the fourth embodiment, when refrigerant leakage is detected in any one of the heat load devices 2a to 2c, the bypass valve 16 is opened. the difference becomes smaller. As a result, the amount of refrigerant passing through the load-side expansion valves 22a to 22c of the heat load devices 2a to 2c in which leakage has been detected decreases, so that the amount of refrigerant leakage can be further reduced.

Embodiment 5.
Embodiment 5 differs from Embodiment 1 in that the operating frequency of compressor 10 is lowered from the current operating frequency when refrigerant leakage is detected in any of heat load devices 2a to 2c. . In the fifth embodiment, the same reference numerals are given to the same parts as in the first embodiment, and the description thereof is omitted.

The air conditioner 100 of Embodiment 5 has the same configuration as the air conditioner 100 of Embodiment 1. Below, the effect obtained by Embodiment 5 is demonstrated by comparing Embodiment 5 and a comparative example. In addition to the control described in Embodiment 1, the heat source side control device 19 of Embodiment 5, when refrigerant leakage is detected in any of the heat load devices 2a to 2c during cooling operation, controls the compressor. 10 is lowered below the current operating frequency. Since the configuration and control details of the air conditioner in the comparative example are the same as those described in Embodiment 1, detailed description thereof will be omitted.

FIG. 12 is a diagram for explaining cooling leakage amounts according to the fifth embodiment and the comparative example. In FIG. 12, the refrigerant leakage amount QI [g/s] according to Embodiment 5 is indicated by white squares for each elapsed time [s] after the refrigerant leakage is detected. Similarly, the refrigerant leakage amount QI [g/s] according to the comparative example is indicated by black circles. In Embodiment 5, by lowering the operating frequency of the compressor 10 from the current operating frequency, the discharge pressure of the compressor 10 is lowered and the suction pressure of the compressor 10 is raised. As a result, the pressure difference between the inlets and outlets of the load-side expansion valves 22a to 22c is reduced. Therefore, the amount of refrigerant passing through the load-side expansion valves 22a to 22c of the heat load devices 2a to 2c in which leakage has been detected decreases. Therefore, as shown in FIG. 12, in the fourth embodiment, the amount of refrigerant that leaks can be reduced more than in the comparative example.

The order of operation of the heat source side control device 19 and the load side control devices 25a to 25c of the fifth embodiment is that after one of steps S2 to S6 described in the first embodiment, the heat source side control device 19 controls the compressor. 10 to which the processing for lowering the operating frequency of 10 below the current operating frequency is added. Therefore, detailed description is omitted.

As described above, in the fifth embodiment, the load-side expansion valves 22a to 22c and solenoid valves 31a to 31c corresponding to the heat load devices 2a to 2c in which refrigerant leakage has occurred are closed, and no refrigerant leakage has occurred. The opening degrees of the load side expansion valves 22a to 22c of the heat load devices 2a to 2c are increased from the current opening degrees. As a result, the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has not occurred increases, and the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has occurred decreases. Therefore, according to Embodiment 5, in the air conditioner 100 having a plurality of heat load devices 2a to 2c connected in parallel to the heat source device 1, refrigerant leakage occurs on the side of the heat load devices 2a to 2c. It is possible to reduce the amount of refrigerant leakage at the time of occurrence.

Further, according to the fifth embodiment, in order to cut off the flow of refrigerant to the heat load devices 2a to 2c in which refrigerant leakage has occurred, the heat load devices 2a to 2c in which refrigerant leakage has not occurred continue to operate. It is possible to Therefore, it is possible to prevent the comfort of the target space in which the heat load devices 2a to 2c are installed from being impaired.

Further, according to the fifth embodiment, when refrigerant leakage is detected in any one of the heat load devices 2a to 2c, the operating frequency of the compressor 10 is lowered below the current operating frequency. The pressure difference between the inlet and outlet of the expansion valves 22a-22c is reduced. As a result, the amount of refrigerant passing through the load-side expansion valves 22a to 22c of the heat load devices 2a to 2c in which leakage has been detected decreases, so that the amount of refrigerant leakage can be further reduced.

Embodiment 6.
FIG. 13 is a circuit diagram of an air conditioner 100A according to Embodiment 6. As shown in FIG. As shown in FIG. 13, the sixth embodiment has a refrigerant heat medium heat exchanger 12A instead of the fan 15 and the refrigerant heat exchanger 12, a pump 41, a flow control valve 42, a heat medium heat exchanger 43, and a heating medium pipe 44, which is different from the first embodiment. In the sixth embodiment, the same reference numerals are given to the same parts as in the first embodiment, and the description thereof is omitted.

The heat source device 1 of the air conditioner 100A of Embodiment 6 has a refrigerant heat medium heat exchanger 12A instead of the fan 15 and the refrigerant heat exchanger 12. The refrigerant heat medium heat exchanger 12A of the heat source device 1 includes a refrigerant flow path (not shown) through which the refrigerant circulating in the refrigerant circuit 6 flows, and a heat medium flow path (not shown) through which the heat medium circulating in the heat medium circuit 7 flows. (not shown) for heat exchange between the refrigerant and the heat medium. The heat medium circuit 7 is formed by connecting the heat medium flow paths of the pump 41, the flow control valve 42, the heat medium heat exchanger 43, and the refrigerant heat medium heat exchanger 12A through the heat medium pipes 44. FIG. The pump 41 is provided in the heat medium pipe 44 and conveys the heat medium to the refrigerant heat medium heat exchanger 12A. The flow rate adjustment valve 42 is provided in the heat medium pipe 44 and adjusts the flow rate of the heat medium circulating through the heat medium circuit 7 . The heat medium heat exchanger 43 exchanges heat between the heat medium and air and supplies hot or cold heat to the heat medium. The heat medium is a fluid different from the refrigerant, such as water. Thus, the refrigerant heat medium heat exchanger 12A of the sixth embodiment is not a so-called air-cooled heat exchanger that exchanges heat between the refrigerant and the air as in the first embodiment. It functions as a so-called water-cooled heat exchanger that exchanges heat with the heat medium that has been heat-exchanged in the vessel 43 .

The heat source side control device 19 of Embodiment 6 controls the operation of the pump 41 and the flow control valve 42 connected by wire or wirelessly. The heat source side control device 19 controls the operating frequency of the pump 41 and the degree of opening of the flow control valve 42 based on the detection results of the sensors described in the first embodiment. Further, the heat source side control device 19 of the sixth embodiment performs the control described in the first embodiment when refrigerant leakage is detected in any one of the heat load devices 2a to 2c.

FIG. 14 is a diagram for explaining the cooling operation of the air conditioner 100A according to Embodiment 6. FIG. FIG. 15 is a diagram for explaining the heating operation of the air conditioner 100A according to Embodiment 6. FIG. As shown in FIGS. 14 and 15, the flow of the refrigerant in the refrigerant circuit 6 during cooling and heating is the same as in the first embodiment, and thus the explanation is omitted.

As described above, in Embodiment 6, the load-side expansion valves 22a to 22c and solenoid valves 31a to 31c corresponding to the heat load devices 2a to 2c in which refrigerant leakage has occurred are closed, and no refrigerant leakage has occurred. The opening degrees of the load side expansion valves 22a to 22c of the heat load devices 2a to 2c are increased from the current opening degrees. As a result, the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has not occurred increases, and the amount of refrigerant supplied to the heat load devices 2a to 2c in which refrigerant leakage has occurred decreases. Therefore, according to Embodiment 6, in the air conditioner 100A having a plurality of heat load devices 2a to 2c connected in parallel to the heat source device 1, refrigerant leakage occurs on the side of the heat load devices 2a to 2c. It is possible to reduce the amount of refrigerant leakage at the time of occurrence.

Further, according to the sixth embodiment, in order to cut off the flow of refrigerant to the heat load devices 2a to 2c in which refrigerant leakage has occurred, the heat load devices 2a to 2c in which refrigerant leakage has not occurred continue to operate. It is possible to Therefore, it is possible to prevent the comfort of the target space in which the heat load devices 2a to 2c are installed from being impaired.

Note that the heat source side control device 19 of Embodiment 6 may perform the control described in

Embodiments

2, 4, or 5 in addition to the control described in Embodiment 1. Further, instead of lowering the air volume of the fan 15 from the current air volume as in Embodiment 3, the operating frequency of the pump 41 may be lowered from the current operating frequency, or the flow control valve 42 may The opening may be made smaller than the current opening. Also in this case, an effect equivalent to that of the third embodiment can be obtained.

Although the embodiments have been described above, the present disclosure is not limited to the above embodiments, and can be variously modified or combined without departing from the gist of the present disclosure. For example, when refrigerant leakage is detected in any of the heat load devices 2a to 2c, in addition to the control described in Embodiment 1, two or more of the controls described in Embodiments 2 to 5 are combined. , may be performed.

Further, in Embodiments 1 to 6, each of the heat load devices 2a to 2c exemplifies a form in which the cooling operation and the heating operation cannot be mixed at the same time. It is also possible to apply the present disclosure to any form.

Also, one or a plurality of devices that control the solenoid valves 31a to 31c or the load-side expansion valves 22a to 22c of the cutoff devices 3a to 3c correspond to the "control device" of the present disclosure. In Embodiments 1 to 6, the heat source side control device 19 controls the electromagnetic valves 31a to 31c of the blocking devices 3a to 3c, and the load side control devices 25a to 25c control the load side expansion valves 22a to 25c. 22c is controlled. However, either the heat source side control device 19 or the load side control devices 25a to 25c is omitted, and the function of controlling the load side expansion valves 22a to 22c and the solenoid valves 31a to 31c is replaced by any one or a plurality of "control devices." ” may be integrated into However, the heat source side control device 19 and the load side control devices 25a to 25c may be provided outside the housings of the heat source device 1 and the heat load devices 2a to 2c.

1 Heat source equipment, 2a, 2b, 2c Heat load equipment, 3a, 3b, 3c Breaker, 4, 5 Refrigerant piping, 6 Refrigerant circuit, 7 Heat medium circuit, 10 Compressor, 11 Flow switching valve, 12 Refrigerant heat exchange vessel, 12A refrigerant heat medium heat exchanger, 13 heat source side expansion valve, 14 accumulator, 15 fan, 16 bypass valve, 17 heat source side refrigerant piping, 18 bypass piping, 19 heat source side control device, 21a, 21b, 21c load

side heat Exchangers

22a, 22b, 22c Load

side expansion valves

23a, 23b, 23c Refrigerant

leakage detection sensors

24a, 24b, 24c Load side

refrigerant pipes

25a, 25b, 25c

Load side controllers

31a, 31b, 31c Solenoid valves , 41 pump, 42 flow control valve, 43 heat medium heat exchanger, 44 heat medium piping, 100, 100A air conditioner.

Claims

a first load-side heat exchanger that exchanges heat between the air in the target space and the refrigerant; a first heat load device having a first load side expansion valve;
a second load-side heat exchanger that exchanges heat between the air in the target space and the refrigerant; a second heat load device having a two-load side expansion valve;
a heat source device having a compressor that compresses refrigerant and supplying refrigerant to the first load heat exchanger and the second load heat exchanger;
a refrigerant pipe that flows a refrigerant therein and connects the first heat load device and the second heat load device in parallel with the heat source device;
a solenoid valve provided in the refrigerant pipe for adjusting the amount of refrigerant flowing into the first heat load device or refrigerant flowing out of the first heat load device;
a controller;
The control device is
When refrigerant leakage in the first heat load device is detected and refrigerant leakage in the second heat load device is not detected, the first load side expansion valve and the electromagnetic valve are closed, and the first load side expansion valve and the solenoid valve are closed. An air conditioner that increases the degree of opening of a two-load side expansion valve from the current degree of opening.
The heat source machine is
Having a heat source side expansion valve that expands the refrigerant,
The control device is
The air conditioner according to claim 1, wherein when refrigerant leakage is detected in the first heat load device or the second heat load device, the degree of opening of the heat source side expansion valve is made smaller than the current degree of opening.
The heat source machine is
a refrigerant heat exchanger that exchanges heat between refrigerant and air;
A fan that sends air to the refrigerant heat exchanger,
The control device is
3. The air conditioner according to claim 1 or 2, wherein when refrigerant leakage is detected in the first heat load device or the second heat load device, the air volume of the fan is reduced below the current air volume.
further comprising a heat medium heat exchanger for exchanging heat between the heat medium and air;
The heat source machine is
3. The air conditioner according to claim 1, further comprising a refrigerant heat medium heat exchanger for exchanging heat between a refrigerant and the heat medium heat-exchanged in the heat medium heat exchanger.
The heat source machine is
a bypass pipe connecting the suction side and the discharge side of the compressor;
a bypass valve that is provided in the bypass pipe and adjusts the amount of refrigerant flowing through the bypass pipe;
The control device is
The air conditioner according to any one of claims 1 to 4, wherein a bypass valve is opened when refrigerant leakage is detected in the first heat load device or the second heat load device.
The control device is
The operating frequency of the compressor is lowered below the current operating frequency when refrigerant leakage is detected in the first heat load device or the second heat load device. air conditioner.