JP6972125B2 - Air conditioner - Google Patents

Description

The present invention relates to a refrigerant leak detection of an air conditioner.

In current air conditioners such as multi air conditioners for buildings, the total length of the refrigerant piping that connects the outdoor unit and the indoor unit may be several hundred meters, and the amount of refrigerant filled in the refrigerant circuit is extremely large. It is increasing. In such an air conditioner, when a refrigerant leak occurs, a large amount of refrigerant may leak into one room.

Further, in recent years, there has been a demand for conversion to a refrigerant having a low global warming potential from the viewpoint of global warming, but many refrigerants having a low global warming potential are flammable. In the future, if the conversion to a refrigerant with a low global warming potential progresses, further consideration for safety will be required.

In order to solve such a problem, a technique has been proposed in which a shutoff valve for shutting off the flow of the refrigerant is provided in the refrigerant circuit to reduce the amount of refrigerant leakage when the refrigerant leaks (for example, Patent Document). 1).

In addition, a technology for installing a refrigerant detection sensor that detects leaked refrigerant in an indoor unit or an air-conditioned space and using the refrigerant detection sensor to operate the shutoff valve appropriately, a method for reducing the number of refrigerant detection sensors installed, and optimum Techniques for various installation positions have also been proposed (see, for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 2000-97527 Japanese Patent No. 3744330

However, the market record of air conditioners equipped with a refrigerant detection sensor is still small, and the refrigerant is caused not only by electrical noise but also by miscellaneous gases such as organic compounds in the air caused by disinfectants and cleaning agents. There was a possibility of false detection of leakage. In addition, in order to suppress the false detection of refrigerant leakage by the refrigerant detection sensor, some measures have been taken such as protecting the sensor part with a filter that can chemically adsorb miscellaneous gas, but this is sufficient. There was a problem that the false detection of refrigerant leakage could not be suppressed.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an air conditioner capable of suppressing false detection of refrigerant leakage.

In the air conditioning device according to the present invention, one or a plurality of indoor units that harmonize the air-conditioned space, one or a plurality of outdoor units that function as heat sources, and the indoor unit and the outdoor unit are connected to each other as a refrigerant pipe. A refrigerant circuit that is connected by the Refrigerant leakage occurred when the detection value of the device constantly exceeded the threshold C1 during the determination time ΔTa, or when the detection value of the refrigerant detection device exceeded the threshold C1 for the reference time or more during the determination time ΔTa. and determining control device, comprising a refrigerant filled in before Symbol refrigerant circuit Ri der flammable refrigerant, the determination time ΔTa is set based on the combustion bottom limit LFL (kg / m ³⁾ and It is a thing.

According to the air conditioner according to the present invention, in the control device, the detection value of the refrigerant detection device is constantly exceeded during the determination time ΔT, the threshold value C1 is constantly exceeded, or the detection value of the refrigerant detection device is during the determination time ΔT. When the threshold value C1 is exceeded for the reference time or more, it is determined that the refrigerant leakage has occurred, so that it is possible to avoid erroneous detection of the refrigerant leakage.

It is a schematic diagram which shows the 1st example of the structure of the air conditioner which concerns on embodiment of this invention. It is a schematic diagram which shows the 2nd example of the structure of the air conditioner which concerns on embodiment of this invention. It is a schematic diagram which shows the 3rd example of the structure of the air conditioner which concerns on embodiment of this invention. It is a schematic diagram which shows the 4th example of the structure of the air conditioner which concerns on embodiment of this invention. It is a schematic diagram which shows the 5th example of the structure of the air conditioner which concerns on embodiment of this invention. It is a schematic diagram which shows the sixth example of the structure of the air conditioner which concerns on embodiment of this invention. It is a schematic diagram which shows the 7th example of the structure of the air conditioner which concerns on embodiment of this invention. It is a schematic diagram which shows the 8th example of the structure of the air conditioner which concerns on embodiment of this invention. It is a schematic diagram which shows an example of the refrigerant circuit structure of the air conditioner which concerns on embodiment of this invention. It is a functional block of the air conditioner according to the embodiment of the present invention. It is a refrigerant circuit diagram which shows the flow of the refrigerant at the time of the total cooling operation of the air conditioner which concerns on embodiment of this invention. It is a refrigerant circuit diagram which shows the flow of the refrigerant at the time of the full heating operation of the air conditioner 100 which concerns on embodiment of this invention. It is a figure explaining an example of the erroneous detection operation of the refrigerant leakage of the conventional air conditioner. It is a figure explaining the erroneous detection avoidance operation of the refrigerant leakage of the air conditioner which concerns on embodiment of this invention. It is a figure which shows the 1st example of the control flow of the refrigerant leakage detection operation of the air conditioner which concerns on embodiment of this invention. It is a figure which shows the 2nd example of the control flow of the refrigerant leakage detection operation of the air conditioner which concerns on embodiment of this invention. It is a figure which shows the 3rd example of the control flow of the detection operation of the refrigerant leakage of the air conditioner which concerns on embodiment of this invention.

Hereinafter, embodiments of the air conditioner 100 of the present invention will be described with reference to the drawings. The form of the drawings is an example and does not limit the present invention. Further, those having the same reference numerals in the respective figures are the same or equivalent thereof, which are common to the entire text of the specification. Further, in the drawings below, the relationship between the sizes of the constituent members may differ from the actual one.

Embodiment.
FIG. 1 is a schematic view showing a first example of the configuration of the air conditioner 100 according to the embodiment of the present invention.
Hereinafter, the configuration of the air conditioner 100 according to the present embodiment will be described.
The air conditioner 100 circulates a refrigerant in a refrigerant circuit 101, which will be described later, and performs air conditioning using a refrigeration cycle. Further, the air conditioner 100 can select a full cooling operation in which all the indoor units to be operated cool the air conditioner and a full heating operation in which the all indoor units to be operated heat the air conditioner 100, such as a multi air conditioner for a building. ..

As shown in FIG. 1, the air conditioner 100 includes one outdoor unit 1 and two indoor units 2a and 2b (hereinafter, collectively referred to as indoor unit 2), and the outdoor unit 1 and the indoor unit 2a. 2b are connected to each other by a refrigerant pipe 3. In the present embodiment, a case where two indoor units 2 are connected to the outdoor unit 1 is shown as an example, but the present invention is not limited to this, and the outdoor unit 1 may be a plurality of units, and the indoor unit 2 may be a plurality of units. It may be one or three or more.

The indoor units 2a and 2b are installed in the air-conditioned spaces 4a and 4b (hereinafter, collectively referred to as the air-conditioned space 4), respectively, and perform air conditioning in the air-conditioned spaces 4a and 4b, respectively. The branching portions 3a and 3b of the refrigerant pipe 3 connecting the outdoor unit 1 and the indoor units 2a and 2b are shut-off devices 7a and 7b (hereinafter,) for blocking the flow of the refrigerant when a refrigerant leak occurs and suppressing the refrigerant leakage. , The generic term is referred to as a blocking device 7). Further, in the air-conditioned spaces 4a and 4b, alarm devices 6a and 6b (hereinafter collectively referred to as alarm devices 6) for notifying the user of the refrigerant leakage when a refrigerant leak occurs, and the leaked refrigerant are exhausted to the outside of the air-conditioned spaces 4a and 4b. Ventilation devices 8a and 8b (hereinafter, collectively referred to as a ventilation device 8) are provided for this purpose.

The indoor unit 2a or the air-conditioning space 4a, and the indoor unit 2b or the air-conditioning space 4b are provided with refrigerant detection devices 5a and 5b (hereinafter, collectively referred to as a refrigerant detection device 5) for detecting refrigerant leakage. There is. In this embodiment, an example is shown in which the refrigerant detection device 5a is provided in the indoor unit 2a and the refrigerant detection device 5b is provided in the air conditioning space 4b, but the present invention is not limited thereto. The refrigerant detection device 5a may be installed in at least one of the indoor unit 2a and the air conditioning space 4a, and the refrigerant detection device 5b may be installed in at least one of the indoor unit 2b and the air conditioning space 4b. good.

The refrigerant detection device 5, the alarm device 6, the shutoff device 7, and the ventilation device 8 are provided as safety measures when the refrigerant leaks from the air conditioner 100. Hereinafter, the refrigerant detection device 5, the alarm device 6, the shutoff device 7, and the ventilation device 8 are collectively referred to as a safety measure device.

In the air conditioner 100 according to the present embodiment, when the refrigerant leakage is detected by the refrigerant detection device 5, the refrigerant leakage output signal is output to the alarm device 6, the shutoff device 7, and the ventilation device 8. .. Then, based on the output refrigerant leakage output signal, all or at least one of them operates to ensure the safety of the air conditioning space 4.

Therefore, since the refrigerant detection device 5, the alarm device 6, the shutoff device 7, and the ventilation device 8 are provided as safety measures when the refrigerant leaks from the air conditioner 100, normal cooling operation or heating operation can be performed. It does not perform any function when it is done. Therefore, if the maximum concentration at the time of refrigerant leakage calculated from the amount of refrigerant filled in the air conditioner 100 and the volume of the air conditioning space 4 does not reach the concentration that affects the human body, the refrigerant detection device 5, the alarm device 6, and the like. The shutoff device 7 and the ventilation device 8 may not be installed.

FIG. 2 is a schematic view showing a second example of the configuration of the air conditioner 100 according to the embodiment of the present invention, and FIG. 3 is a diagram showing the configuration of the air conditioner 100 according to the embodiment of the present invention. 3 is a schematic diagram showing three examples, FIG. 4 is a schematic diagram showing a fourth example of the configuration of the air conditioner 100 according to the embodiment of the present invention, and FIG. 5 is a schematic view showing the embodiment of the present invention. FIG. 6 is a schematic diagram showing a fifth example of the configuration of the air conditioner 100 according to the present invention, and FIG. 6 is a schematic diagram showing a sixth example of the configuration of the air conditioner 100 according to the embodiment of the present invention. FIG. 7 is a schematic view showing a seventh example of the configuration of the air conditioner 100 according to the embodiment of the present invention.

It is sufficient that any one or more of the alarm device 6, the shutoff device 7, and the ventilation device 8 are installed. Of these, the cases where one or two types are installed are shown in FIGS. 2 to 8.

FIG. 2 is an air conditioning device 100 in the case where the alarm devices 6a and 6b are provided in the air conditioning spaces 4a and 4b, respectively, as a safety measure. FIG. 3 is an air conditioner 100 in the case where the shutoff devices 7a and 7b are provided at the branch portions 3a and 3b of the refrigerant pipe 3 as safety measures. FIG. 4 is an air conditioning device 100 in the case where the ventilation devices 8a and 8b are provided in the air conditioning spaces 4a and 4b, respectively, as a safety measure. In FIG. 5, as a safety measure, the alarm devices 6a and 6b are provided in the air-conditioned spaces 4a and 4b, respectively, and the shutoff devices 7a and 7b are provided in the branch portions 3a and 3b of the refrigerant pipe 3, respectively. The harmonizing device 100.

FIG. 6 is an air conditioning device 100 in the case where the alarm devices 6a and 6b and the ventilation devices 8a and 8b are provided in the air conditioning spaces 4a and 4b, respectively, as a safety measure. FIG. 7 is an air conditioner 100 when the shutoff device 7 is provided in the refrigerant pipe 3 inside the outdoor unit 1 as a safety measure. Since the shutoff device 7 may be provided outside the air conditioning spaces 4a and 4b, it may be provided inside the outdoor unit 1 as shown in FIG. 7.

FIG. 8 is a schematic view showing an eighth example of the configuration of the air conditioner 100 according to the embodiment of the present invention.
As shown in FIG. 8, in the air conditioning device 100 according to the present embodiment, a plurality of indoor units 2a and 2b may be installed in the same air-conditioned space 4. In this case, as a safety measure, for example, the alarm device 6 is provided in the air conditioning space 4, and the shutoff devices 7a and 7b are provided in the branch portions 3a and 3b of the refrigerant pipe 3, respectively.

Next, the configuration of the refrigerant circuit 101 of the air conditioner 100 according to the present embodiment will be described.
FIG. 9 is a schematic view showing an example of the configuration of the refrigerant circuit 101 of the air conditioner 100 according to the embodiment of the present invention.
As shown in FIG. 9, the air conditioner 100 according to the present embodiment includes a compressor 10, a refrigerant flow path switching device 11, a heat source side heat exchanger 12, throttle devices 41a and 41b, and a load side heat exchanger 40a. 40b, the accumulator 13 is sequentially connected by the refrigerant pipe 3, and includes a refrigerant circuit 101 in which the refrigerant circulates. Hereinafter, the throttle devices 41a and 41b are collectively referred to as the throttle device 41, and the load side heat exchangers 40a and 40b are collectively referred to as the load side heat exchanger 40.

[Outdoor unit 1]
The outdoor unit 1 functions as a heat source, and includes a compressor 10, a refrigerant flow path switching device 11, a heat source side heat exchanger 12, and an accumulator 13. Further, an outdoor blower 14 for blowing air to the heat source side heat exchanger 12 is provided in the vicinity of the heat source side heat exchanger 12.

The compressor 10 sucks in a low-temperature low-pressure refrigerant and compresses the refrigerant into a high-temperature and high-pressure state, and is composed of an inverter compressor or the like whose capacity can be controlled. The refrigerant flow path switching device 11 switches between the flow of the refrigerant during the cooling operation and the flow of the refrigerant during the heating operation, and is composed of a four-way valve or the like.

The heat source side heat exchanger 12 functions as a condenser during the cooling operation and as an evaporator during the heating operation, and exchanges heat between the air supplied from the outdoor blower 14 such as a fan and the refrigerant. ..

Further, the outdoor unit 1 is provided with a first pressure detecting device 20 and a second pressure detecting device 21 for detecting pressure. The first pressure detecting device 20 is provided in the refrigerant pipe 3 connecting the discharge side of the compressor 10 and the refrigerant flow path switching device 11, and presses the pressure of the high-temperature and high-pressure refrigerant compressed by the compressor 10 and discharged. It is to detect. Further, the second pressure detecting device 21 is provided in the refrigerant pipe 3 connecting the refrigerant flow path switching device 11 and the suction side of the compressor 10, and detects the pressure of the low-temperature low-pressure refrigerant sucked into the compressor 10. It is something to do.

Further, the outdoor unit 1 is provided with a first temperature detecting device 22 for detecting the temperature. The first temperature detection device 22 is provided in the refrigerant pipe 3 connecting the discharge side of the compressor 10 and the refrigerant flow path switching device 11, and measures the temperature of the high-temperature and high-pressure refrigerant compressed and discharged by the compressor 10. It detects and is composed of a thermistor and the like.

[Indoor unit 2a, 2b]
The indoor units 2a and 2b harmonize the air-conditioned spaces 4a and 4b with air, and include load-side heat exchangers 40a and 40b and throttle devices 41a and 41b, respectively. Further, indoor blowers 42a and 42b (hereinafter collectively referred to as indoor blowers 42) for blowing air to the load side heat exchangers 40a and 40b are provided in the vicinity of the load side heat exchangers 40a and 40b, respectively. .. Further, the indoor units 2a and 2b are connected to the outdoor unit 1 via the refrigerant pipe 3, so that the refrigerant flows in and out.

The load side heat exchanger 40 functions as an evaporator during the cooling operation and as a condenser during the heating operation, exchanges heat between the air supplied from the indoor blower 42 such as a fan and the refrigerant, and performs heat exchange between the air conditioning space. It produces heating air or cooling air to be supplied to 4. The throttle device 41 has functions as a pressure reducing valve and an expansion valve, decompresses and expands the refrigerant, and is composed of a device whose opening degree can be variably controlled, for example, an electronic expansion valve.

Further, the indoor units 2a and 2b include second temperature detection devices 50a and 50b (hereinafter collectively referred to as the second temperature detection device 50) and third temperature detection devices 51a and 51b (hereinafter collectively referred to as the second temperature detection device 50) for detecting the temperature. The third temperature detection device 51) and the fourth temperature detection devices 52a and 52b (hereinafter, collectively referred to as the fourth temperature detection device 52) are provided.

The second temperature detecting device 50 is provided in the refrigerant pipe 3 connecting the throttle device 41 and the load side heat exchanger 40, and detects the temperature of the refrigerant flowing into the load side heat exchanger 40 during the cooling operation. be. Further, the third temperature detection device 51 is provided in the refrigerant pipe 3 on the side opposite to the throttle device 41 with respect to the load side heat exchanger 40, and the refrigerant flowing out from the load side heat exchanger 40 during the cooling operation is provided. It detects the temperature. Further, the fourth temperature detecting device 52 is provided in the air suction portion of the load side heat exchanger 40, and detects the air temperature in the air conditioning space 4.

The second temperature detection device 50, the third temperature detection device 51, and the fourth temperature detection device 52 are composed of a thermistor or the like.

[Control device 30]
Further, the outdoor unit 1 includes a control device 30. The control device 30 is composed of, for example, dedicated hardware or a CPU (also referred to as a central processing unit, a processing unit, a computing device, a microprocessor, a microcomputer, or a processor) that executes a program stored in a memory. Has been done.

FIG. 10 is a functional block of the air conditioner 100 according to the embodiment of the present invention.
As shown in FIG. 10, the control device 30 includes a main control unit 31, a timer unit 32, a storage unit 33, and a drive unit 34.
The main control unit 31 turns on / off the alarm device 6, opens / closes the shutoff device 7, and rotates the ventilation device 8 (ON) based on the detection values of various detection devices and instructions from the remote controller (not shown). (Including / OFF), frequency of compressor 10, rotation speed of outdoor blower 14 of heat source side heat exchanger 12 (including ON / OFF), switching of refrigerant flow path switching device 11, opening of throttle device 41, and load. The drive unit 34 is instructed to control the rotation speed (including ON / OFF) of the indoor blower 42 of the side heat exchanger 40.

The various detection devices include a refrigerant detection device 5, a first pressure detection device 20, a second pressure detection device 21, a first temperature detection device 22, a second temperature detection device 50, a third temperature detection device 51, and the like. A fourth temperature detection device 52 is included.

The timer unit 32 measures the time. The storage unit 33 stores various information such as the threshold value C1 described later.
Based on the instruction from the main control unit 31, the drive unit 34 turns on / off the alarm device 6, opens / closes the shutoff device 7, rotates the ventilation device 8 (including ON / OFF), the frequency of the compressor 10, and the heat source. The rotation speed (including ON / OFF) of the outdoor blower 14 of the side heat exchanger 12, the switching of the refrigerant flow path switching device 11, the opening degree of the throttle device 41, and the rotation speed of the indoor blower 42 of the load side heat exchanger 40. It controls (including ON / OFF).

In this embodiment, an example in which the control device 30 is provided in the outdoor unit 1 is shown, but the present invention is not limited to this, and the control device 30 may be provided separately for each unit of the outdoor unit 1 and the indoor units 2a and 2b. Alternatively, it may be provided in either the outdoor unit 1 or the indoor units 2a and 2b. Further, the control device 30 is configured to include the timer unit 32 and the storage unit 33, but the present invention is not limited to this, and the timer unit 32 and the storage unit 33 may be provided separately from the control device 30. good.

The shutoff device 7 cuts off the flow of the refrigerant pipe 3 in order to suppress the refrigerant leak from the outdoor unit 1 to the air conditioning space 4 when the refrigerant leaks from the indoor unit 2 or its vicinity. .. Therefore, the shutoff device 7 may be any device as long as it can shut off the flow of the refrigerant in the refrigerant circuit 101, and may be a device that can be controlled only by opening / closing, such as a solenoid valve, or an electronic expansion valve. The opening may be variably controllable.

[Full cooling operation]
FIG. 11 is a refrigerant circuit 101 showing the flow of the refrigerant during the total cooling operation of the air conditioner 100 according to the embodiment of the present invention. In FIG. 11, the flow direction of the refrigerant is indicated by a solid arrow. Further, the refrigerant flow path switching device 11 is switched so that the discharge side of the compressor 10 and the heat source side heat exchanger 12 are connected to each other. In FIG. 11, the total cooling operation of the air conditioner 100 will be described by taking as an example a case where a cold heat load is generated in the load side heat exchangers 40a and 40b.

In the case of full cooling operation, the low temperature and low pressure refrigerant is compressed by the compressor 10 and discharged as a high temperature and high pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 10 flows into the heat source side heat exchanger 12 via the refrigerant flow path switching device 11. The high-temperature high-pressure gas refrigerant that has flowed into the heat source-side heat exchanger 12 condenses while radiating heat to the outdoor air to become a high-pressure liquid refrigerant. Then, the high-pressure liquid refrigerant flowing out of the heat source side heat exchanger 12 flows out from the outdoor unit 1, passes through the refrigerant pipe 3, and flows into the indoor units 2a and 2b. At this time, the shutoff devices 7a and 7b are in an open state so as not to obstruct the flow of the refrigerant.

The high-pressure liquid refrigerant that has flowed into the indoor units 2a and 2b is decompressed into a low-temperature low-pressure two-phase refrigerant by the throttle devices 41a and 41b, and then flows into the load-side heat exchangers 40a and 40b that act as evaporators, and is indoors. By absorbing heat from the air, it cools the indoor air and becomes a low-temperature, low-pressure gas refrigerant. The low-temperature low-pressure gas refrigerant flowing out of the load-side heat exchangers 40a and 40b flows into the outdoor unit 1 through the refrigerant pipe 3. The refrigerant that has flowed into the outdoor unit 1 passes through the refrigerant flow path switching device 11 and the accumulator 13 and is sucked into the compressor 10.

In the control device 30, the superheat (superheat degree) obtained as the difference between the temperature detected by the second temperature detecting devices 50a and 50b and the temperature detected by the third temperature detecting devices 51a and 51b is constant. In addition, the opening degree of the throttle devices 41a and 41b is controlled. By doing so, the capacity corresponding to the heat load of the air-conditioned spaces 4a and 4b can be exhibited, and efficient operation becomes possible.

[Full heating operation]
FIG. 12 is a refrigerant circuit 101 showing the flow of the refrigerant during the full heating operation of the air conditioner 100 according to the embodiment of the present invention. In FIG. 12, the flow direction of the refrigerant is indicated by a solid arrow. Further, the refrigerant flow path switching device 11 is switched so that the discharge side of the compressor 10 and the shutoff devices 7a and 7b are connected. In FIG. 12, the full heating operation of the air conditioner 100 will be described by taking as an example a case where a thermal load is generated in the load side heat exchangers 40a and 40b.

In the case of full heating operation, the low temperature and low pressure refrigerant is compressed by the compressor 10 and discharged as a high temperature and high pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the compressor 10 passes through the refrigerant pipe 3 via the refrigerant flow path switching device 11 and flows into the indoor units 2a and 2b. At this time, the shutoff devices 7a and 7b are in an open state so as not to obstruct the flow of the refrigerant.

The high-temperature high-pressure gas refrigerant flowing into the indoor units 2a and 2b dissipates heat to the indoor air in the load-side heat exchangers 40a and 40b, becomes a high-pressure liquid refrigerant, and flows into the throttle devices 41a and 41b. Then, after the pressure is reduced to the low-temperature low-pressure two-phase refrigerant by the throttle devices 41a and 41b, the indoor units 2a and 2b flow out, pass through the refrigerant pipe 3, and flow into the outdoor unit 1.

The low-temperature low-pressure two-phase refrigerant flowing into the outdoor unit 1 flows into the heat source side heat exchanger 12 and absorbs heat from the outdoor air to become a low-temperature low-pressure gas refrigerant. The low-temperature low-pressure gas refrigerant exiting the heat source-side heat exchanger 12 passes through the refrigerant flow path switching device 11 and the accumulator 13 and is sucked into the compressor 10.

The control device 30 is a subcool (overcooling degree) obtained as a difference between the saturated liquid temperature of the refrigerant calculated from the pressure detected by the first pressure detecting device 20 and the temperature detected by the second temperature detecting device 50. Is constant, the opening degrees of the throttle devices 41a and 41b are controlled. By doing so, the capacity corresponding to the heat load of the air-conditioned spaces 4a and 4b can be exhibited, and efficient operation becomes possible.

Next, an operation for avoiding erroneous detection of refrigerant leakage of the air conditioner 100 according to the present embodiment will be described.
FIG. 13 is a diagram illustrating an example of a refrigerant leakage erroneous detection operation of a conventional air conditioner, and FIG. 14 is a diagram showing a refrigerant leakage erroneous detection avoidance operation of the air conditioner 100 according to the embodiment of the present invention. It is a figure explaining.
Conventionally, the control device of the air conditioner has a threshold value of the refrigerant concentration, and when the detection value (refrigerant concentration) detected by the refrigerant leak device exceeds the threshold value, it is generally determined that the refrigerant leak has occurred. there were. However, in this method, as shown in FIG. 13, even if the refrigerant concentration temporarily exceeds the threshold value due to miscellaneous gas, noise, etc., it is determined that the refrigerant has leaked, and erroneous detection of the refrigerant leak has occurred. Was there.

Therefore, the control device 30 of the air conditioner 100 according to the present embodiment is characterized by having a refrigerant leakage determination function for avoiding the above-mentioned false detection of refrigerant leakage.
Hereinafter, the refrigerant leakage determination function will be described in detail.

[Refrigerant leakage judgment function]
The refrigerant leakage determination function of the control device 30 of the air conditioner 100 is a function of determining whether or not a refrigerant leakage has occurred by using both the refrigerant leakage determination time and the threshold value of the refrigerant concentration.

Hereinafter, a more specific description of the refrigerant leakage determination function will be given. When a refrigerant leak occurs, the time ΔT (s) from the occurrence of the refrigerant leak until the refrigerant concentration in the air-conditioned space 4 reaches C (kg / m ³ ) is expressed by the following equation.

[Number 1]
ΔT = C × A × H / G (1)

In Equation 1, A is the floor area (m ² ) of the air conditioning space 4, H is the ceiling height (m) of the air conditioning space 4, and G is the leakage rate of the refrigerant (kg / s).

Further, assuming that the threshold value of the refrigerant concentration is C1 (kg / m ³ ), the time ΔT1 (s) from the occurrence of the refrigerant leakage to the arrival at the threshold value C1 is expressed by the following equation.

[Number 2]
ΔT1 = C1 × A × H / G (2)

Further, if the refrigerant leakage is detected before the refrigerant concentration in the air conditioning space 4 reaches LFL / 2 (kg / m ³ ) using the lower combustion limit LFL (kg / m ³ ), the air conditioning space 4 has a problem. Page 221 (http://www.jsrae.or.jp/www.jsrae.orjp/ww.jsrae.orjp/com. It is reported in final_report_2016r1_en.pdf).

Therefore, if the refrigerant leakage is detected before the refrigerant concentration in the air-conditioned space 4 reaches LFL / 2 (kg / m ³ ) and the safety countermeasure device is operated, ignition in the air-conditioned space 4 can be suppressed. can. Here, the time ΔT2 (s) from the occurrence of the refrigerant leakage until the refrigerant concentration in the air conditioning space 4 reaches LFL / 2 is expressed by the following equation.

[Number 3]
ΔT2 = (LFL / 2) × A × H / G (3)

From the above, when the safety measure device operates immediately, the control device 30 detects the refrigerant concentration of the threshold C1 after ΔT1 second by the refrigerant detection device 5 with reference to the time when the refrigerant leak occurs, and the air conditioning space 4 If it is determined that the refrigerant leakage has occurred before ΔT 2 seconds after the refrigerant concentration of the above becomes LFL / 2, the safety is ensured.

The determination time ΔTa (s), which is the maximum time allowed from the occurrence of the refrigerant leakage to the determination of the refrigerant leakage by the control device 30, is expressed by the following equation.

[Number 4]
ΔTa = ΔT2-ΔT1 = ((LFL / 2) -C1) × A × H / G (4)

Refrigerant leakage occurs due to cracks in the refrigerant pipe 3 and corrosion of the heat exchanger in the indoor unit 2. That is, once the refrigerant leaks, the hole through which the refrigerant leaks is not closed, so that the refrigerant leak continues until the amount of the refrigerant in the air conditioner 100 is reduced. On the other hand, a sterilizing spray or the like, which causes a false detection of refrigerant leakage, is sprayed in a short time.

Therefore, in order to suppress erroneous detection of refrigerant leakage, the refrigerant is detected when the refrigerant concentration exceeding the threshold value C1 is detected by the refrigerant detecting device 5, and then the refrigerant concentration exceeding the threshold value C1 is continuously detected for a certain period of time. A method of determining that it is a leak can be considered. However, although there is a possibility that a transmission error of the detection signal from the refrigerant detection device 5 may occur, even if a signal transmission error occurs, the ratio is small, so that the time exceeding the threshold value C1 is a predetermined ratio or more. If the presence is used as a determination criterion, a signal transmission error can be suppressed.

That is, the refrigerant concentration detected by the refrigerant detecting device 5 constantly exceeds the threshold value C1 or sets the threshold value C1 by the time when the determination time ΔTa (s) elapses after the refrigerant leakage occurs. By performing the refrigerant leakage determination based on the determination criterion that the time exceeded is a predetermined ratio or more, it is possible to suppress erroneous detection of the refrigerant leakage.

The control interval of the control device 30 of the air conditioner 100 is 10 seconds or more even if it is short, and in order to suppress erroneous detection of refrigerant leakage, it is necessary to detect the refrigerant leakage a plurality of times at this control interval. In addition, it seems that the time for spraying the disinfectant spray or the like is at most several seconds. Therefore, it is the shortest determination time for refrigerant leakage that the refrigerant detection device 5 continuously detects the refrigerant concentration exceeding the threshold value C1 for 20 seconds or more, and the determination time ΔTa needs to be a value of 20 (s) or more. There is.

Further, since it is necessary to determine the leakage of the refrigerant before all the refrigerant filled in the refrigerant circuit 101 leaks, the amount of refrigerant M (kg) filled in the refrigerant circuit 101 satisfies the following equation. There is a need.

[Number 5]
M ≧ ΔT2 × G (5)

In addition, page 221 (http://www.jsrae.or.jp/committe/bine_frompage2016) of Risk Assessment of Mildly Refrigerants Final Report 2016 (March 2017) published by the Japan Society of Refrigerating and Air-Conditioning. The leakage rate of the refrigerant in the indoor unit of the air conditioner harmonizer is 10 (kg / h) = 10/3600 (kg / s). Further, considering that the standard ceiling height in the room is 2.2 (m), the equations (1) to (5) are expressed as follows.

[Number 1A]
ΔT = C × A × H / G
= C x A x 2.2 / (10/3600)
= 792 x C x A (6)

[Number 2A]
ΔT1 = C1 × A × H / G
= C1 x A x 2.2 / (10/3600)
= 792 x C1 x A (7)

[Number 3A]
ΔT2 = (LFL / 2) × A × H / G
= (LFL / 2) x A x 2.2 / (10/3600)
= 396 x LFL x A (8)

[Number 4A]
ΔTa = ((LFL / 2) -C1) × A × H / G
= ((LFL / 2) -C1) x A x 2.2 / (10/3600)
= 792 x (LFL / 2-C1) x A (9)
[Number 5A]
M ≧ ΔT2 × G
= (LFL / 2) x A x (H / G) x G
= 396 x LFL x A x G
= (LFL / 2) × A × H
= (LFL / 2) x A x 2.2
= 1.1 x LFL x A (10)

As an example, the refrigerant filled in the refrigerant circuit 101 is R32 refrigerant, the floor area A of the air conditioning space 4 is 9 (m ² ), and the threshold C1 of the refrigerant detection device 5 is 0.0307 (kg / m ³ ). Then, since the LFL of the R32 refrigerant is 0.307 (kg / m ³ ), ΔT1 is about 219 seconds (≈3.7 minutes), ΔT2 is about 1094 seconds (≈18.2 minutes), and ΔTa is about 875. Seconds (≈14.5 minutes), M is about 3.0 (kg).

In the above-mentioned example of the R32 refrigerant, the determination time ΔTa (s), which is the maximum time allowed from the detection of the refrigerant concentration exceeding the threshold C1 to the determination of the refrigerant leakage, is set to about 875 seconds. However, the safety of the air-conditioned space 4 can be guaranteed. As a matter of course, since the determination time ΔTa (s) is the maximum allowable time, it may be set to a smaller value in actual operation.

Since the amount of refrigerant to be filled in the refrigerant circuit 101 is predetermined, the LFL of the leaking refrigerant is known in advance. Further, the threshold value C1 is also predetermined by the refrigerant detection device 5 used. Therefore, LFL and C1 in the equation (9) can be set as constants, and if an R32 refrigerant is used and the threshold value C1 is 0.0307 (kg / m ³ ), the equation (9) becomes the following equation. Therefore, ΔTa can be calculated by using only the floor area A.

[Number 4B]
ΔTa = ((LFL / 2) -C1) × A × H / G
= 792 x (0.307 / 2-0.037) x A
= 92.268 × A (11)

Further, the air conditioning load L of the general air conditioning space 4 takes a value such as ^{0.1 (kW / m 2).} Since the air conditioning capacity Q (kW) of the indoor unit 2 is stored in the storage unit 33 of the control device 30, the floor area A can be obtained by using the air conditioning capacity Q and the air conditioning load L of the indoor unit 2. ΔTa can also be calculated by the following equation. That is, ΔTa can be calculated only by the value of the air conditioning capacity Q of the indoor unit 2. When a plurality of indoor units 2 are installed in one air-conditioning space 4, the total air-conditioning capacity of the plurality of indoor units 2 may be set as Q.

[Number 4C]
ΔTa = ((LFL / 2) -C1) × (Q / L) × H / G
= 792 x (0.307 / 2-0.037) x (Q / 0.1)
= 922.68 × Q (12)

Further, when the equation (9) is rewritten, it becomes the following equation, and ΔTa may be specified by the value calculated by the equation (13).

[Number 4D]
ΔTa = ((LFL / 2) -C1) × (Q / L) × H / G
= 792 x ((LFL / 2) -C1) x (Q / 0.1)
= 7920 x ((LFL / 2) -C1) x Q (13)

Similarly, when the equation (10) is rewritten, it becomes the following equation, and M may be defined by the value calculated by the equation (14).

[Number 5B]
M ≧ ΔT2 × G
= (LFL / 2) x (Q / L) x (H / G) x G
= (LFL / 2) × (Q / L) × H
= (LFL / 2) x (Q / 0.1) x 2.2
= 11 x LFL x Q (14)

Therefore, as shown in FIG. 14, even if the control device 30 detects the refrigerant concentration exceeding the threshold value C1 by the refrigerant detection device 5 due to electrical noise and miscellaneous gas such as an organic compound system in the air. It is not immediately determined that the refrigerant has leaked. Then, the control device 30 can determine whether or not the refrigerant leakage is really occurring from the detection value Cd of the refrigerant detection device 5 during the determination time ΔTa (s), and suppresses erroneous detection of the refrigerant leakage. It becomes possible to do.

Next, a specific example of a method for suppressing false detection of refrigerant leakage will be described. As a method of suppressing false detection of refrigerant leakage using the determination time ΔTa (s), the following measures can be taken.
The condition for determining that the refrigerant leakage has occurred is always set to the threshold value from the time when the ^{detection value Cd by the refrigerant detection device 5 exceeds the threshold value C1 (kg / m 3) until the determination time ΔTa (s) elapses.} If the condition exceeds C1, it is possible to suppress erroneous detection of refrigerant leakage due to miscellaneous gas in the air.

In addition, the condition for determining that the refrigerant leakage has occurred is that the determination time ΔTa (s) elapses after the ^{detection value Cd by the refrigerant detection device 5 exceeds the threshold value C1 (kg / m 3).} Even under the condition that the ratio exceeding the threshold value C1 is a predetermined ratio or more, it is possible to suppress erroneous detection of refrigerant leakage due to miscellaneous gas in the air.

As yet another determination condition, the detection value Cd by the refrigerant detection device 5 is sampled at regular intervals, and the detection value Cd by the refrigerant detection device 5 continues for a reference number of times until the determination time ΔTa (s) elapses. If the threshold value C1 is exceeded, it may be determined that the refrigerant has leaked.

In the present embodiment, in the above-mentioned explanation of the refrigerant leakage determination function, the refrigerant filled in the refrigerant circuit 101 is an R32 refrigerant which is a flammable refrigerant, and the lower limit LFL of the refrigerant is used for the explanation. .. However, the refrigerant filled in the refrigerant circuit 101 is not limited to the flammable refrigerant, and even if a nonflammable refrigerant or a toxic refrigerant is used and the refrigerant concentration limit RCL (Refrigerant Concentration Limit) of the nonflammable refrigerant and the toxic refrigerant is used. , The same effect can be obtained.

FIG. 15 is a diagram showing a first example of a control flow of a refrigerant leakage detection operation of the air conditioner 100 according to the embodiment of the present invention.
Next, a first example of the control flow of the refrigerant leakage detection operation of the air conditioner 100 according to the present embodiment will be described with reference to FIG.

First, the main control unit 31 determines whether or not the detection value Cd by the refrigerant detection device 5 exceeds the threshold value C1 stored in the storage unit 33 (step S1A).

When the main control unit 31 determines that the detected value Cd exceeds the threshold value C1 (YES in step S1A), the timer unit 32 starts measuring the time t (step S2A).

After step S2A, the main control unit 31 determines whether or not the time t exceeds the determination time ΔTa stored in the storage unit 33 (step S3A).

When the main control unit 31 determines that the time t does not exceed the determination time ΔTa (NO in step S3A), the main control unit 31 determines whether or not the detection value Cd exceeds the threshold value C1 (step S4A).

In step S4A, when the detection value Cd is determined not to exceed the threshold value C1 (NO in step S4A), the main control unit 31 ends the process.

On the other hand, when the main control unit 31 determines that the detected value Cd exceeds the threshold value C1 (YES in step S4A), the main control unit 31 returns to step S3A.

In step S3A, when the main control unit 31 determines that the time t exceeds the determination time ΔTa (YES in step S3A), the drive unit 34 operates the safety countermeasure device. That is, the main control unit 31 is turned ON for the alarm device 6, opened for the shutoff device 7, and turned ON for the ventilation device 8 (step S5A).

From the above, the main control unit 31 repeats the processes of steps S3A and S4A while the detection value Cd exceeds the threshold value C1, and is safe when the detection value Cd constantly exceeds the threshold value C1 during the determination time ΔTa. The countermeasure device is operating.

FIG. 16 is a diagram showing a second example of a control flow of a refrigerant leakage detection operation of the air conditioner 100 according to the embodiment of the present invention.
Next, a second example of the control flow of the refrigerant leakage detection operation of the air conditioner 100 according to the present embodiment will be described with reference to FIG.

First, the main control unit 31 starts the measurement of the time t by the timer unit 32, and resets the on time Δton and the off time Δtoff to 0 (step S1B). Here, the on time Δton is the total time when the detected value Cd exceeds the threshold value C1, and the off time Δtoff is the total time when the detected value Cd does not exceed the threshold value C1. Next, the main control unit 31 determines whether or not the detection value Cd by the refrigerant detection device 5 exceeds the threshold value C1 stored in the storage unit 33 (step S2B).

When the main control unit 31 determines that the detection value Cd exceeds the threshold value C1 (YES in step S2B), the main control unit 31 adds time to the on-time Δton (step S3B), and proceeds to step S5B.

On the other hand, when the main control unit 31 determines that the detection value Cd does not exceed the threshold value C1 (NO in step S2B), the time is added to the off time Δtoff (step S4B), and the process proceeds to step S5B. The process of step S4B can be omitted.

Here, in steps S3B and S4B, the time to be added to the on-time Δton or the off-time Δtoff is the time from the determination process in the previous step S2B to the current step S2B. For example, when the main control unit 31 performs the determination process in step S2B every second, the above addition time is 1 second.

In step S5B, the main control unit 31 determines whether or not the time t exceeds the determination time ΔTa stored in the storage unit 33.

When the main control unit 31 determines that the time t exceeds the determination time ΔTa (YES in step S5B), the main control unit 31 proceeds to step S6B.

On the other hand, when the main control unit 31 determines that the time t does not exceed the determination time ΔTa (NO in step S5B), the main control unit 31 returns to step S2B. That is, the main control unit 31 repeats the processes of steps S2B to S5B until the time t exceeds the determination time ΔTa. Then, during the determination time ΔTa, the detection value Cd does not exceed the threshold value C1 during the Δon time ton, which is the total time during which the detection value Cd exceeds the threshold value C1, and during the determination time ΔTa. Find the off time Δtoff, which is the total time.

In step S6B, the main control unit 31 determines whether or not the on-time Δton exceeds the reference time xΔTa stored in the storage unit 33. Here, regarding the reference time xΔTa, for example, when the determination time ΔTa is 30 seconds and the preset ratio x is 80%, the reference time xΔTa is 30 × (8/10) = 24 seconds.

When the main control unit 31 determines that the on-time Δton exceeds the reference time xΔTa (YES in step S6B), the drive unit 34 operates the safety countermeasure device. That is, the main control unit 31 is turned ON for the alarm device 6, opened for the shutoff device 7, and turned ON for the ventilation device 8 (step S7B).

On the other hand, when the main control unit 31 determines that the on-time Δton does not exceed the reference time xΔTa (NO in step S6B), the main control unit 31 ends the process.

From the above, the main control unit 31 measures the total time when the detected value Cd exceeds the threshold value C1 during the determination time ΔTa, and when the total measured time is equal to or more than the reference time xΔTa, the safety measure device. Is operating.

FIG. 17 is a diagram showing a third example of a control flow of a refrigerant leakage detection operation of the air conditioner 100 according to the embodiment of the present invention.
Next, a third example of the control flow of the refrigerant leakage detection operation of the air conditioner 100 according to the present embodiment will be described with reference to FIG.

First, the main control unit 31 starts measuring the time t by the timer unit 32, and resets the counter K to 0 (step S1C). Next, the main control unit 31 determines whether or not the detection value Cd by the refrigerant detection device 5 exceeds the threshold value C1 stored in the storage unit 33 (step S2C).

When the main control unit 31 determines that the detected value Cd exceeds the threshold value C1 (YES in step S2C), 1 is added to the counter K (step S3C), and the process proceeds to step S5C.

On the other hand, when the main control unit 31 determines that the detected value Cd does not exceed the threshold value C1 (NO in step S2C), the counter K is reset (step S4C), and the process proceeds to step S5C.

In step S5C, the main control unit 31 determines whether or not the value of the counter K has reached the reference number of times Ka stored in the storage unit 33.

When the main control unit 31 determines that the value of the counter K has reached the reference number of times Ka (YES in step S5C), the drive unit 34 operates the safety countermeasure device. That is, the main control unit 31 is turned ON for the alarm device 6, opened for the shutoff device 7, and turned ON for the ventilation device 8 (step S7C).

On the other hand, when the main control unit 31 determines that the value of the counter K has not reached the reference number of times Ka (NO in step S5C), the main control unit 31 proceeds to step S6C.

In step S6C, the main control unit 31 determines whether or not the time t exceeds the determination time ΔTa stored in the storage unit 33.

When the main control unit 31 determines that the time t exceeds the determination time ΔTa (YES in step S6C), the main control unit 31 ends the process.

On the other hand, when the main control unit 31 determines that the time t does not exceed the determination time ΔTa (NO in step S6C), the main control unit 31 returns to step S2C. That is, the main control unit 31 repeats the processes of steps S2C to S5C until the time t exceeds the determination time ΔTa, and the detection value Cd continuously exceeds the threshold value C1 for the reference number of times Ka during the determination time ΔTa. It is judged whether or not it was.

From the above, the main control unit 31 measures the number of times that the detected value Cd continuously exceeds the threshold value C1 during the determination time ΔTa, and when the measured number of times is equal to or more than the reference number of times Ka, the safety measure device is installed. It is working.

As described above, in the air conditioner 100 according to the present embodiment, the refrigerant detection device 5 for detecting the refrigerant leakage from the refrigerant circuit 101 and the detection value Cd of the refrigerant detection device 5 constantly exceed the threshold value C1 during the determination time ΔT. In this case, or when the detection value Cd of the refrigerant detection device 5 exceeds the threshold value C1 by the reference time xΔTa or more during the determination time ΔT, the control device 30 for determining that the refrigerant leakage has occurred is provided. ..

According to the air conditioner 100 according to the present embodiment, the control device 30 detects when the detection value Cd of the refrigerant detection device 5 constantly exceeds the threshold value C1 during the determination time ΔT, or the detection of the refrigerant detection device 5. When the value Cd exceeds the threshold value C1 by the reference time xΔTa or more during the determination time ΔT, it is determined that the refrigerant leakage has occurred, so that the false detection of the refrigerant leakage can be suppressed.

Further, the air conditioning device 100 according to the present embodiment includes at least one of an alarm device 6, a ventilation device 8, and a shutoff device 7, and the control device 30 determines that a refrigerant leak has occurred, the alarm device 6 is provided. , At least one of the ventilation device 8 and the shutoff device 7 is operated.

According to the air conditioning device 100 according to the present embodiment, by operating the safety measure device when it is determined that the refrigerant leakage has occurred, ignition in the air conditioning space 4 can be suppressed, and the safety of the air conditioning space 4 can be suppressed. Can be guaranteed.

Further, in the air conditioning device 100 according to the present embodiment, the control device 30 samples the detection value of the refrigerant detection device 5 at regular intervals, and the detection value of the refrigerant detection device 5 is the reference number of times during the determination time ΔTa. When Ka continuously exceeds the threshold value C1, it is determined that a refrigerant leak has occurred.

According to the air conditioner 100 according to the present embodiment, the control device 30 samples the detection value of the refrigerant detection device 5 at regular intervals, and the detection value of the refrigerant detection device 5 is the reference number of times during the determination time ΔTa. When Ka continuously exceeds the threshold value C1, it is determined that the refrigerant leak has occurred, so that the false detection of the refrigerant leak can be suppressed.

1 outdoor unit, 2 indoor unit, 2a indoor unit, 2b indoor unit, 3 refrigerant piping, 3a branch part, 3b branch part, 4 air conditioning space, 4a air conditioning space, 4b air conditioning space, 5 refrigerant detection device, 5a refrigerant detection device, 5b Refrigerator detection device, 6 alarm device, 6a alarm device, 6b alarm device, 7 cutoff device, 7a cutoff device, 7b cutoff device, 8 ventilation device, 8a ventilation device, 8b ventilation device, 10 compressor, 11 refrigerant flow path switching Equipment, 12 heat source side heat exchanger, 13 accumulator, 14 outdoor blower, 20 first pressure detector, 21 second pressure detector, 22 first temperature detector, 30 controller, 31 main controller, 32 timer section, 33 Storage unit, 34 Drive unit, 40 Load side heat exchanger, 40a Load side heat exchanger, 40b Load side heat exchanger, 41 Squeezing device, 41a Squeezing device, 41b Squeezing device, 42 Indoor blower, 42a Indoor blower, 42b Indoor blower, 50 second temperature detector, 50a second temperature detector, 50b second temperature detector, 51 third temperature detector, 51a third temperature detector, 51b third temperature detector, 52 fourth temperature detector Device, 52a 4th temperature detector, 52b 4th temperature detector, 100 air conditioner, 101 refrigerant circuit.

Claims (8)

With one or more indoor units that harmonize the air-conditioned space with air,
One or more outdoor units that function as heat sources,
A refrigerant circuit in which the indoor unit and the outdoor unit are connected by a refrigerant pipe and the refrigerant circulates.
A refrigerant detection device that is provided inside the indoor unit or in an air-conditioned space where the indoor unit harmonizes with air and detects refrigerant leakage from the refrigerant circuit.
Refrigerant leakage when the detection value of the refrigerant detection device constantly exceeds the threshold value C1 during the determination time ΔTa, or when the detection value of the refrigerant detection device exceeds the threshold value C1 for the reference time or more during the determination time ΔTa. Equipped with a control device that determines that
Before SL is flammable refrigerant der refrigerant charged in the refrigerant circuit is, the determination time ΔTa, the air conditioning apparatus is set based on the combustion bottom limit LFL (kg / m ^3). The floor area of the air-conditioned space where the indoor unit is installed is A (m ² ),
The ceiling height of the air-conditioned space where the indoor unit is installed is H (m),
The leakage rate of the refrigerant filled in the refrigerant circuit is G (kg / s),
The total air conditioning capacity of the indoor unit is Q (kW),
When the air conditioning load of the air conditioning space where the indoor unit is installed is L (kW / m ² ),
The determination time ΔTa is less than a value calculated by ((LFL / 2) −C1) × A × H / G or ((LFL / 2) −C1) × (Q / L) × H / G. The air conditioner according to claim 1. The amount of the refrigerant filled in the refrigerant circuit is equal to or greater than the value calculated by (LFL / 2) × A × H or (LFL / 2) × (Q / L) × H. Air conditioner. Claimed that the leakage rate is G = 10/3600 (kg / s), the ceiling height is H = 2.2 (m), and the air conditioning load is L = 0.1 (kW / m ² ). The air conditioner according to 2 or 3. With one or more indoor units that harmonize the air-conditioned space with air,
One or more outdoor units that function as heat sources,
A refrigerant circuit in which the indoor unit and the outdoor unit are connected by a refrigerant pipe and the refrigerant circulates.
A refrigerant detection device that is provided inside the indoor unit or in an air-conditioned space where the indoor unit harmonizes with air and detects refrigerant leakage from the refrigerant circuit.
Refrigerant leakage when the detection value of the refrigerant detection device constantly exceeds the threshold value C1 during the determination time ΔTa, or when the detection value of the refrigerant detection device exceeds the threshold value C1 for the reference time or more during the determination time ΔTa. Equipped with a control device that determines that
Before SL is incombustible refrigerant or toxic refrigerant der refrigerant charged in the refrigerant circuit is, the determination time ΔTa, the air conditioning apparatus is set based on the refrigerant concentration limit RCL (kg / m ^3). Equipped with at least one of an alarm device that notifies the user of refrigerant leakage, a ventilation device that exhausts the leaked refrigerant, and a blocking device that blocks the flow of refrigerant.
The air conditioner according to any one of claims 1 to 5, wherein the control device operates at least one of the alarm device, the ventilation device, and the shutoff device when it is determined that a refrigerant leak has occurred. The air conditioner according to any one of claims 1 to 6, wherein the determination time ΔTa is 20 seconds or more. The control device samples the detection value of the refrigerant detection device at regular intervals, and when the detection value of the refrigerant detection device continuously exceeds the threshold value C1 for the reference number of times during the determination time ΔTa, the refrigerant leakage occurs. The air conditioner according to any one of claims 1 to 7, wherein the air conditioner is determined to have occurred.

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