JP6443177B2 - Air conditioner - Google Patents

Description

  The present invention relates to an air conditioner in which an indoor unit and an outdoor unit are connected via a refrigerant circuit.

  In an air conditioner using a flammable refrigerant, if the amount of refrigerant leakage exceeds a certain amount, there is a possibility that the refrigerant may ignite. Therefore, a safety measure has been conventionally taken, such as notifying refrigerant leakage. For example, Patent Document 1 is known as a technique for notifying refrigerant leakage. Patent Document 1 discloses that refrigerant leakage occurs when the temperature difference between the intake air temperature of a heat exchanger functioning as an evaporator and the low-pressure refrigerant temperature that is the temperature of the refrigerant that has passed through the heat exchanger is smaller than a threshold value. Is disclosed.

JP-A-3-175244

  By the way, the danger at the time of refrigerant | coolant leakage differs with an air conditioning apparatus according to the installation environment of an outdoor unit. For example, when an outdoor unit is installed in a partially enclosed space such as a semi-underground space, if the semi-underground space becomes deeper, the refrigerant tends to accumulate in the semi-underground space. Becomes higher.

  In addition, there are various types of indoor units such as a floor-standing type, a wall-mounted type, and a ceiling-mounted type, and the danger at the time of refrigerant leakage varies depending on these types. For example, in a floor-standing indoor unit, the refrigerant piping is installed along the floor, so that the leaked refrigerant tends to accumulate on the floor, and there is a high risk of refrigerant leakage.

  However, in the technique of Patent Document 1, since the threshold value for determining the detection of the refrigerant leak is constant, the refrigerant leak cannot be detected in consideration of the danger at the time of the refrigerant leak of each air conditioner. There's a problem.

  An object of this invention is to provide the air conditioning apparatus which detects the refrigerant | coolant leakage in consideration of the danger at the time of the refrigerant | coolant leakage of each air conditioning apparatus.

  An air conditioner (2) according to an aspect of the present invention is an air conditioner (2) in which an indoor unit and an outdoor unit are connected via a refrigerant circuit that circulates a flammable refrigerant, wherein the outdoor unit is installed. An acquisition unit (211) that acquires installation information indicating an environment, an estimation unit (213) that estimates the degree of refrigerant leakage from the refrigerant circuit, and a high risk of refrigerant leakage due to the installation environment of the outdoor unit A determination unit (212) that determines one determination level according to the installation information from among a plurality of determination levels with different degrees of refrigerant leakage so that the leakage detection timing becomes earlier, and the estimation unit (213) ) And a detection unit (214) for detecting refrigerant leakage by comparing the degree of refrigerant leakage estimated by (1) with the determination level of 1 determined by the determination unit (212).

  According to this configuration, the installation information indicating the installation environment of the outdoor unit is acquired, and one determination level corresponding to the acquired installation information is determined. Then, the degree of refrigerant leakage from the refrigerant circuit is estimated, and the estimated degree of refrigerant leakage is compared with the determined one determination level to detect refrigerant leakage. Here, the determination unit (212) determines the determination level of 1 so that the leakage detection timing is advanced as the risk of refrigerant leakage due to the installation environment of the outdoor unit increases. Therefore, it is possible to detect refrigerant leakage at an appropriate timing in consideration of the danger at the time of refrigerant leakage due to the installation environment of the outdoor unit.

  In the air conditioner (2), the determination unit (212) compares the determination level according to the type of the indoor unit with the determination level according to the installation information of the outdoor unit to detect leakage. The determination level with the earlier timing may be adopted.

  According to this configuration, the determination level according to the type of the indoor unit is compared with the determination level according to the installation information of the outdoor unit, and refrigerant leakage is detected using the determination level with the earlier leakage detection level. Therefore, the detection of refrigerant leakage is delayed, and the refrigerant can be prevented from igniting.

  In the air conditioner (2), the installation information may include information indicating a refrigerant filling amount in the refrigerant circuit and a volume of an installation space in which the outdoor unit is installed.

  According to this configuration, since the installation information includes information indicating the refrigerant charging amount and the volume of the installation space in which the outdoor unit is installed, the refrigerant leaks at an appropriate timing in consideration of the information. Can be detected.

  In the air conditioner (2), the detection unit (214) causes the degree of refrigerant leakage estimated by the estimation unit (213) to reach a determination level of 1 determined by the determination unit (212). In such a case, the refrigerant leakage may be notified.

  According to this configuration, when the degree of the refrigerant leakage amount estimated by the estimation unit (213) reaches the determination level determined by the determination unit (212), refrigerant leakage is detected. Here, since the determination level is determined in consideration of at least the danger in the installation environment of the outdoor unit, refrigerant leakage can be detected at an appropriate timing according to the installation environment.

  ADVANTAGE OF THE INVENTION According to this invention, a refrigerant | coolant leak can be detected at the appropriate timing which considered the danger at the time of the refrigerant | coolant leak of each air conditioning apparatus.

It is a schematic block diagram of the air conditioning apparatus in embodiment of this invention. It is a block diagram which shows the electrical structure of the air conditioning apparatus centering on a controller. It is a flowchart which shows operation | movement of the air conditioning apparatus when the determination level is determined in embodiment of this invention. It is a flowchart which shows operation | movement of the air conditioning apparatus at the time of refrigerant | coolant leakage being detected in embodiment of this invention. It is explanatory drawing of the process which determines the determination level according to a model. It is explanatory drawing of the process which determines the determination level according to installation information.

  Hereinafter, an air conditioner according to an embodiment of the present invention will be described with reference to the drawings.

[Air conditioning equipment]
FIG. 1 is a schematic configuration diagram of an air conditioner 2 according to an embodiment of the present invention. The air conditioner 2 is for performing indoor cooling or heating. The air conditioner 2 includes a refrigerant circuit 2C that performs a vapor compression refrigeration cycle. The air conditioner 2 includes an outdoor unit 21 and an indoor unit 22, and the outdoor unit 21 and the indoor unit 22 are connected via a refrigerant circuit 2C.

A combustible refrigerant can be used as the refrigerant filled in the refrigerant circuit 2C. Examples of combustible refrigerants that have a low global warming potential (hereinafter referred to as “GWP”), such as natural refrigerants R290 (C ₃ H ₈ : propane) and R1270 (C ₃ H ₆ : propylene). HC refrigerant can be used. However, in the present embodiment, R32 (CH ₂ F ₂ : difluoromethane), which is an HFC refrigerant that does not have a carbon double bond in its composition and has recently attracted attention as a refrigerant having a low GWP, is adopted as the refrigerant. However, the present invention is not limited to this, and a halogenated hydrocarbon refrigerant which is a kind of HFC refrigerant and has a carbon double bond in its composition may be employed. The halogenated hydrocarbons, for _{example, HFO-1234yf (CF 3 CF} = CH 2: tetrafluoropropane) and _{HFO-1234 ze (CF 3 -CH} = CHF) can be employed.

Such an HFC refrigerant with a low GWP is not as flammable as an HC refrigerant such as R290, which is a natural refrigerant, but unlike R410A, which is nonflammable, has a slightly flammable level of flammability. For this reason, in the present embodiment, such a flammable refrigerant having a flammability level is also referred to as a flammable refrigerant. Further, as the refrigerant, R717 (NH ₃ : ammonia) which is a refrigerant having a low GWP and has a flammability of a slight combustion level may be employed.

  The refrigerant circuit 2C is provided with a compressor 23, an accumulator AC, a four-way switching valve 24, an outdoor heat exchanger 25, an expansion mechanism 26, and an indoor heat exchanger 27. The compressor 23, the four-way switching valve 24, the outdoor heat exchanger 25, and the expansion mechanism 26 are provided in the outdoor unit 21. The indoor heat exchanger 27 is provided in the indoor unit 22. The outdoor unit 21 is provided with an outdoor fan 28 for supplying outdoor air to the outdoor heat exchanger 25, and the indoor unit 22 is provided with an indoor fan 29 for supplying indoor air to the indoor heat exchanger 27. Is provided.

  In the refrigerant circuit 2C, the compressor 23 has a discharge side connected to the first port P1 of the four-way switching valve 24, and a suction side connected to the second port P2 of the four-way switching valve 24 via the accumulator AC. In the refrigerant circuit 2C, an outdoor heat exchanger 25, an expansion mechanism 26, and an indoor heat exchanger 27 are arranged in order from the third port P3 to the fourth port P4 of the four-way switching valve 24.

  The compressor 23 may be a scroll type or rotary type compressor, but is not limited thereto. In the present embodiment, the compressor 23 is configured such that its rotational speed is variable. Specifically, the electric motor of the compressor 23 is connected to a commercial power source via an inverter. When the output frequency of the inverter is changed, the rotational speed of the electric motor changes, and as a result, the rotational speed of the compressor 23 changes. When the rotational speed of the compressor 23 is increased, the operating capacity of the compressor 23 is increased, and when the rotational speed of the compressor 23 is decreased, the operating capacity of the compressor 23 is decreased. Here, although the compressor with the variable rotational speed of the electric motor is employed as the compressor 23, the compressor is not limited to this, and a compressor with a constant rotational speed of the electric motor may be employed.

  The accumulator AC stores the separated liquid refrigerant in order to separate the liquid refrigerant and the gas refrigerant and cause the compressor 23 to suck the gas refrigerant.

  As the outdoor heat exchanger 25 and the indoor heat exchanger 27, for example, a fin-and-tube heat exchanger can be used, but is not limited thereto. The outdoor heat exchanger 25 exchanges heat between the outdoor air and the refrigerant in the refrigerant circuit 2C. The indoor heat exchanger 27 exchanges heat between the indoor air and the refrigerant in the refrigerant circuit 2C. The expansion mechanism 26 can use, for example, an expansion valve such as an electronic expansion valve, but is not limited thereto.

  The four-way switching valve 24 has a first state in which the first port P1 communicates with the third port P3 and the second port P2 communicates with the fourth port P4 (a state indicated by a solid line in FIG. 1), and the first port P1 The state is switched to a second state (state indicated by a broken line in FIG. 1) in which the second port P2 communicates with the third port P3 and communicates with the fourth port P4. The air conditioner 2 performs a cooling operation when in the first state, and performs a heating operation when in the second state. Therefore, the refrigerant flows in the direction indicated by the solid line during cooling, and the refrigerant flows in the direction indicated by the dotted line during heating.

  The indoor unit 22 is provided with a temperature sensor 301 that detects the temperature of indoor air sucked into the indoor heat exchanger 27.

  The outdoor unit 21 is provided with a temperature sensor 302 that measures the temperature of outdoor air sucked into the outdoor heat exchanger 25.

  Further, in the liquid pipe 2C_1 that connects the indoor heat exchanger 27 and the expansion mechanism 26, a temperature sensor 401 that measures the temperature of the refrigerant that passes through the connection location is provided in the vicinity of the connection location with the indoor heat exchanger 27, A temperature sensor 402 that measures the temperature of the refrigerant that passes through the connection point is provided in the vicinity of the connection point with the expansion mechanism 26.

  Further, in the liquid pipe 2C_2 that connects the outdoor heat exchanger 25 and the expansion mechanism 26, a temperature sensor 403 that measures the temperature of the refrigerant that passes through the connection location is provided in the vicinity of the connection location with the outdoor heat exchanger 25. A temperature sensor 404 that measures the temperature of the refrigerant that passes through the connection point is provided in the vicinity of the connection point with the expansion mechanism 26.

[controller]
FIG. 2 is a block diagram showing an electrical configuration of the air conditioning apparatus 2 with the controller 200 as the center.

  The controller 200 includes a control unit 210 and a storage unit 220. For example, the control unit 210 includes a processor such as a CPU, and the storage unit 220 includes a rewritable nonvolatile storage device such as a flash memory.

  The controller 200 may be provided in the outdoor unit 21 or may be provided in the indoor unit 22. The controller 200 is connected to the air conditioner 2, the temperature sensors 301, 302, 401 to 404, and the like via a communication line (not shown), and can transmit / receive information to / from them. Note that transmission / reception of information may be performed wirelessly instead of the communication line.

  The input device 250 is a device for inputting installation information of the outdoor unit 21. The input device 250 may be configured with a remote control for operating the air conditioning device 2 or may be configured with a dedicated input device used by an operator who installs the air conditioning device 2. As a dedicated input device, for example, a portable terminal in which an application for inputting various information to the air conditioner 2 is installed can be employed. For example, the input device 250 is connected to the controller 200 so as to be able to communicate wirelessly. As a wireless communication system, for example, infrared communication, Bluetooth (registered trademark), IEEE802.11 series wireless LAN, or near field wireless communication such as NFC may be used. It may be.

  The input device 250 may be connected to the controller 200 so as to be communicable via a wired cable such as a USB cable.

  The control unit 210 includes functions of an acquisition unit 211, a determination unit 212, an estimation unit 213, and a detection unit 214.

  For example, the acquisition unit 211 controls a communication interface (not shown) for communicating with the input device 250, acquires installation information of the outdoor unit 21 from the input device 250, and stores it in the installation information storage unit 221.

The installation information is information indicating the installation environment of the outdoor unit 21, and includes, for example, information indicating the volume of the installation space in which the outdoor unit 21 is installed and the refrigerant filling amount charged in the refrigerant circuit 2C.
As information indicating the volume of the installation space, for example, if the outdoor unit 21 is installed in a depression called a semi-underground space, the height of the depression (hereinafter referred to as “half-underground height”). And the bottom area of the depression.

  Further, the acquisition unit 211 acquires the identification information of the indoor unit 22 and stores it in the identification information storage unit 222. Here, the identification information is stored in advance in a memory provided in a controller (not shown) of the indoor unit 22. Therefore, if the controller 200 is provided in the outdoor unit 21, the acquisition unit 211 is configured such that, for example, when the air conditioner 2 is installed, the controller 200 and the controller of the indoor unit 22 are communicably connected. In addition, the identification information may be acquired by accessing the memory of the controller and stored in the identification information storage unit 222. If the controller 200 is provided in the indoor unit 22, the acquisition unit 211 may read the identification information stored in advance in the identification information storage unit 222 as necessary.

  The worker who installs the air conditioner 2 measures the semi-underground height and the bottom area when the air conditioner 2 is installed, for example, and inputs the obtained values to the input device 250, so Get underground height and bottom area. In addition, for example, the worker causes the acquisition unit 211 to acquire the refrigerant filling amount by inputting the refrigerant filling amount actually filled when the air conditioner 2 is installed to the input device 250.

  The determination unit 212 installs the outdoor unit 21 from a plurality of determination levels having different degrees of refrigerant leakage so that the leakage detection timing is advanced as the risk of refrigerant leakage due to the installation environment of the outdoor unit 21 increases. A determination level of 1 according to information is determined. In addition, the determination unit 212 determines whether the indoor unit 22 has a plurality of determination levels having different degrees of refrigerant leakage so that the leakage detection timing is earlier in the indoor unit 22 of a type that has a higher risk of being affected on the human body when the refrigerant leaks. A determination level of 1 corresponding to the model is determined. Then, the determination unit 212 determines the determination level with the earlier leakage detection timing among the determination levels, and stores the determination level in the determination level storage unit 223.

  Here, as the degree of the refrigerant leakage amount, a ratio of the refrigerant filling amount leaked from the refrigerant circuit 2C when the initial refrigerant filling amount of the refrigerant circuit 2C is 100% can be employed.

  Therefore, the plurality of determination levels include, for example, a plurality of predetermined refrigerant leakage amounts such as a determination level of the refrigerant leakage amount of 40%, a determination level of 45%, and a determination level of 50%. Judgment level is included.

  As will be described later, since the refrigerant leakage is detected when the degree of the refrigerant leakage amount leaked from the refrigerant circuit 2C reaches the determination level, the leakage detection timing becomes earlier as the degree of the refrigerant leakage amount indicated by the determination level becomes smaller. Become.

  Here, the determination unit 212 may determine the model of the indoor unit 22 from the identification information of the indoor unit 22 stored in the identification information storage unit 222. In this embodiment, as a model of the indoor unit 22, for example, a floor-mounted type, a ceiling-mounted type such as a ceiling-embedded type or a ceiling-suspended type, and a wall-mounted type are assumed, but this is an example. Here, the identification information employs, for example, a symbol system including a symbol string indicating the model of the indoor unit 22 and a symbol string for specifying each indoor unit 22. Therefore, the determination unit 212 can determine the type of the indoor unit from the symbol string indicating the type included in the identification information. In addition, identification information is not limited to this, For example, the information which shows a model itself may be employ | adopted.

  For example, the estimation unit 213 calculates a temperature difference ΔT between the first temperature T1 detected by the first temperature sensor 230 and the second temperature T2 detected by the second temperature sensor 240, and uses the calculated temperature difference ΔT. Thus, the degree of refrigerant leakage from the refrigerant circuit 2C is estimated.

  Here, as the first temperature T <b> 1 and the second temperature T <b> 2, various temperatures can be adopted according to the refrigerant leakage detection logic adopted by the air conditioner 2. In the present embodiment, the detection logic uses a temperature of air sucked by a heat exchanger functioning as an evaporator (suction temperature) and a temperature of the refrigerant evaporated by the heat exchanger (evaporation temperature). Is adopted.

  In this case, since the indoor heat exchanger 27 serves as an evaporator during the cooling operation, the temperature sensor 301 is employed as the first temperature sensor 230, and the suction temperature of the indoor unit 22 measured by the temperature sensor 301 is the first temperature T1. Become. Further, during the cooling operation, the temperature sensor 401 is employed as the second temperature sensor 240, and the evaporation temperature measured by the temperature sensor 401 becomes the second temperature T2.

  On the other hand, since the outdoor heat exchanger 25 serves as an evaporator during heating operation, the temperature sensor 302 is employed as the first temperature sensor 230, and the suction temperature of the outdoor unit 21 measured by the temperature sensor 302 is the first temperature T1. Become. Moreover, the temperature sensor 403 is employ | adopted as the 2nd temperature sensor 240 at the time of heating operation, and the evaporation temperature which the temperature sensor 403 measured becomes 2nd temperature T2.

  Here, when the refrigerant leakage amount increases, the refrigerant filling amount in the refrigerant circuit 2C decreases, and thus the evaporation temperature rises. On the other hand, the suction temperature of the air sucked by the heat exchanger is not affected by the amount of refrigerant leakage. Therefore, since the temperature difference ΔT obtained by subtracting the second temperature T2 from the first temperature T1 decreases as the refrigerant leakage amount increases, the degree of refrigerant leakage amount can be estimated from the temperature difference ΔT.

  Specifically, the estimation unit 213 determines the degree of refrigerant leakage corresponding to the temperature difference ΔT using a function or a lookup table in which the relationship between the temperature difference ΔT and the degree of refrigerant leakage is predetermined. Good.

  Here, although the estimation part 213 estimated the degree of the refrigerant | coolant leakage amount based on temperature, this is an example. For example, the estimation unit 213 may estimate the degree of refrigerant leakage based on the pressure of the refrigerant flowing through the refrigerant circuit 2C. For example, when the refrigerant leakage amount increases, the pressure of the refrigerant compressed by the compressor 23 becomes lower than the assumed refrigerant pressure. Therefore, the degree of the refrigerant leakage amount is estimated such that the refrigerant leakage amount increases as the pressure measured by the pressure sensor provided in the pipe near the outlet of the compressor 23 becomes lower than the reference pressure value. That's fine.

  When the degree of the refrigerant leakage amount estimated by the estimation unit 213 reaches the determination level stored in the determination level storage unit 223, the detection unit 214 detects the occurrence of refrigerant leakage and notifies the refrigerant leakage. Here, the detection unit 214 may notify the refrigerant leakage by displaying a message indicating that the refrigerant leakage has occurred on the display panel of the remote controller (not shown) of the air conditioner 2. As the message, for example, the phrase “refrigerant is leaking” can be adopted. Alternatively, if the remote controller includes a speaker, the detection unit 214 may output a sound or an alarm sound indicating that refrigerant leakage has occurred from the speaker. Or if the lighting lamp for alerting | reporting refrigerant | coolant leakage is provided in the indoor unit 22 or the outdoor unit 21, the detection part 214 may alert | report refrigerant | coolant leakage by lighting this lighting lamp. Alternatively, if the controller 200 is connected to a monitoring device (for example, a server) of the management company of the air conditioning apparatus 2 via an external network, the detection unit 214 sends a message indicating that the refrigerant has leaked to this monitoring device. You may alert | report a refrigerant | coolant leak by transmitting.

[Decision level determination]
FIG. 3 is a flowchart showing the operation of the air conditioning apparatus 2 when the determination level is determined in the embodiment of the present invention. This flowchart may be executed, for example, when power is first turned on at the time of installation of the air conditioner 2, or may be executed when the air conditioner 2 is regularly checked. It may be executed when power is first turned on at the time of relocation.

  First, the acquisition unit 211 acquires installation information input by a worker using the input device 250 (S301), and stores it in the installation information storage unit 221.

  Next, the determination unit 212 uses the acquired installation information to calculate a risk index indicating the level of danger at the time of refrigerant leakage due to the installation environment of the outdoor unit 21 (S302).

  Here, the determination unit 212 may calculate the risk index K using a predetermined function f (H, A, M). However, H is a semi-underground height, A is the bottom area of a semi-underground space, M shows a refrigerant | coolant filling amount.

  Since the danger at the time of refrigerant leakage increases as the semi-underground height H increases, the function f (H, A, M) is set so that the risk index K increases as the semi-underground height H increases. Has been. Further, since the risk of refrigerant leakage increases as the refrigerant filling amount per unit volume in the semi-underground space increases, the function f (H, A, M) is expressed as refrigerant filling amount M / volume of the semi-underground space. The risk index K is set so as to increase as V increases. However, the volume V of the semi-underground space is semi-underground height H × bottom area A.

  Next, the determination unit 212 calculates the degree of the allowable refrigerant leakage amount until the calculated risk index K exceeds the predetermined reference value Kth (S303). The reference value Kth is a value indicating that it is necessary to immediately report the leakage of the refrigerant when the risk index K becomes a value higher than this, and a value determined in advance according to the type of the refrigerant is adopted.

  If the installation environment of the outdoor unit 21 does not change, the semi-underground height H and the bottom area A are constant, so the risk index K is a function of the refrigerant charge amount M. Therefore, the reference value Kth−danger index K = ΔK has a value corresponding to the degree of the allowable refrigerant leakage amount (a value where the degree of the allowable refrigerant leakage amount decreases as ΔK decreases). Accordingly, the determination unit 212 calculates the degree of the allowable refrigerant leakage amount using the value of ΔK. For example, the determination unit 212 may calculate the degree of the allowable refrigerant amount using a lookup table or function in which ΔK and the degree of the allowable refrigerant leakage amount are associated in advance.

  However, this calculation method is merely an example, and the determination unit 212 may calculate the degree of the allowable refrigerant leakage amount using another method.

  Next, the determination unit 212 determines one determination level corresponding to the installation information of the outdoor unit 21 from a plurality of predetermined determination levels using the degree of the allowable refrigerant leakage amount calculated in S303 ( S304). FIG. 6 is an explanatory diagram of processing for determining a determination level according to installation information. In this example, the degree of the allowable refrigerant leakage amount calculated in S303 is Lx. Further, three determination levels 601, 602, and 603 whose allowable refrigerant leakage amounts are L21, L22, and L23 are employed as a plurality of determination levels. However, L21 <L22 <L23, and the leakage detection timing is the earliest at the determination level 601, the next determination level 602 is the earliest, and the next determination level 603 is early.

  Here, let us consider a case where the allowable refrigerant leakage amount degree Lx is L21 <Lx <L22 and has a value between determination levels 601 and 602. In this case, the determination unit 212 employs the determination level 601 with the earlier leakage detection timing among the determination levels 601 and 602, that is, the determination level 601 with the stricter determination conditions. Thus, the risk of refrigerant leakage is detected in advance, and the leakage detection timing is prevented from being delayed.

  Thus, the determination unit 212 detects two determination levels sandwiching the allowable refrigerant leakage amount degree Lx, and determines one of the two determination levels with the earlier leakage detection timing as one determination according to the installation information. Decide as a level.

  Returning to FIG. 3, in S305, the determination unit 212 acquires the identification information of the indoor unit 22 from the identification information storage unit 222 (S305), and determines the model of the indoor unit 22 from the acquired identification information (S306). .

  Next, the determination unit 212 determines one determination level according to the model of the indoor unit 22 from a plurality of predetermined determination levels (S307). FIG. 5 is an explanatory diagram of processing for determining the determination level according to the model. In the example of FIG. 5, a floor-standing type, a wall-mounted type, and a ceiling-mounted type are adopted as types. The floor-standing type is associated with a determination level 501 with an allowable refrigerant leakage amount of L11, and the wall-mounted type is associated with a determination level 502 with an allowable medium leakage amount of L12, and the ceiling. The installation type is associated with a determination level 503 having an allowable refrigerant leakage amount L13.

  However, L11 <L12 <L13. This is because the floor-standing type takes into account that the danger of refrigerant leakage is higher than other types. That is, since the floor-standing indoor unit 22 is directly installed on the floor, the refrigerant pipes are also arranged along the floor, and the leaked refrigerant accumulates on the floor. For this reason, the floor-standing indoor unit 22 is associated with a determination level 501 that has earlier leak detection timing than other types.

  Moreover, since the wall-mounted type and ceiling-mounted type indoor unit 22 has a longer distance to the floor than the floor-mounted type, the leaked refrigerant is more likely to diffuse than the floor-mounted type. Therefore, the wall-hanging indoor unit 22 is associated with a determination level 502 with an allowable refrigerant leakage amount of L12, and the ceiling-mounted indoor unit 22 has a determination level 503 with an allowable refrigerant leakage amount of L13. Are associated. In the example of FIG. 5, the ceiling-mounted indoor unit 22 has an allowable refrigerant leakage degree L13 larger than the wall-mounted indoor unit 22 allowable refrigerant quantity degree L12. This is because it is assumed that the leaked refrigerant is more easily diffused than the wall-mounted type.

  However, the determination level is not limited to this. For example, the determination level may be associated with the floor-standing indoor unit 22 and the other types of indoor units 22. For example, the determination level 501 is associated with the floor-standing indoor unit 22, and the determination level 502 is associated with the indoor unit 22 other than the floor-standing indoor unit 22 regardless of the ceiling-mounted type or the wall-mounted type. It may be attached.

  As described above, in the present embodiment, a determination level that is earlier in leak detection timing is assigned to a model that has a higher risk of affecting the human body when refrigerant leaks.

  Returning to FIG. In S308, the determination unit 212 compares the determination level of 1 according to the installation information determined in S304 with the determination level of 1 according to the type determined in S307, and determines the determination level with the earlier leak detection timing. select.

  Then, the determination unit 212 stores the determination level 1 determined in S308 in the determination level storage unit 223 (S309). Thereafter, the refrigerant leakage is detected using the determination level stored in the determination level storage unit 223.

  Next, the processing of S308 will be described with reference to FIGS. In the following description, the allowable refrigerant leakage amounts L21 to L23 of the determination levels 601 to 603 are values between the allowable refrigerant leakage amount L11 of the determination level 501 and the allowable refrigerant leakage amount L12 of the determination level 502. Suppose you have That is, it is assumed that there is a relationship of L11 <L21 <L22 <L23 <L12.

  In this case, since the degree L11 of the allowable refrigerant leakage amount at the determination level 501 is smaller than the degree L21 of the allowable refrigerant leakage amount at the determination level 601, if the type of the indoor unit 22 is a floor-standing type, the installation information of the outdoor unit 21 is included. Regardless, the determination level 501 is determined as a determination level of 1.

  Since L23 <L12, if the type of the indoor unit 22 is a wall-mounted type or a ceiling-mounted type, a determination level corresponding to the installation information is selected regardless of the type of the indoor unit 22.

  When the determination level is set as in this example, if the type of the indoor unit 22 is a floor-standing type with a high risk, the determination level 501 with the earliest leak detection timing is selected, so that the leak detection timing is delayed. Can be prevented. On the other hand, in the case of a wall-mounted or ceiling-mounted indoor unit 22 with a relatively low risk, an appropriate determination level is selected according to the installation information of the outdoor unit 21, so that the leak detection timing is unnecessarily fast. It is possible to prevent inconvenience to the user.

  Note that the above-described magnitude relationship of the allowable refrigerant leakage amount is merely an example, and other magnitude relationships may be employed. For example, the allowable refrigerant leakage amount degrees L12 and L13 of the determination levels 502 and 503 may be smaller than the allowable refrigerant leakage amount degree L23 of the determination level 603 (L12, L13 <L23).

[Detection of refrigerant leakage]
FIG. 4 is a flowchart showing the operation of the air conditioning apparatus 2 when refrigerant leakage is detected in the embodiment of the present invention. This flowchart may be executed every time the air conditioner 2 is driven, or may be periodically executed while the air conditioner 2 is being driven.

  First, the estimation unit 213 causes the first temperature sensor 230 and the second temperature sensor 240 to measure the first temperature T1 and the second temperature T2 (S401).

  Next, the estimation unit 213 calculates the temperature difference ΔT by subtracting the second temperature T2 from the first temperature T1 (S402). Next, the estimation unit 213 estimates the degree of refrigerant leakage from the temperature difference ΔT (S403). Next, if the degree of refrigerant leakage estimated by the estimation unit 213 is equal to or higher than the determination level stored in the determination level storage unit 223 (YES in S404), the detection unit 214 detects refrigerant leakage (S405). The refrigerant leakage is notified (S406). On the other hand, if the degree of the refrigerant leakage amount estimated by the estimation unit 213 is less than the determination level stored in the determination level storage unit 223 (NO in S404), the detection unit 214 does not notify the refrigerant leakage and performs processing. finish.

[Summary of embodiment]
In the present embodiment, the determination level of 1 according to the installation information indicating the installation environment of the outdoor unit 21 and the determination level of 1 according to the type of the indoor unit 22 are compared, and the determination level with the earlier leak detection timing Is finally determined as a determination level of 1 and stored in the determination level storage unit 223. Thereafter, the refrigerant leakage is detected using the determination level stored in the determination level storage unit 223. Here, the determination level determined according to the installation information of the outdoor unit 21 is determined such that the leak detection timing is advanced as the risk of refrigerant leakage due to the installation environment of the outdoor unit 21 increases. Therefore, when the determination level according to the installation information is finally determined as 1 determination level, the refrigerant leakage can be detected at an appropriate timing taking into consideration the danger at the time of refrigerant leakage due to the installation environment of the outdoor unit 21 .

  Further, the determination level determined according to the type of the indoor unit 22 is determined so that the leakage detection timing is earlier for a type having a higher risk to the human body when the refrigerant leaks. Therefore, when the determination level determined according to the model of the indoor unit 22 is finally determined as a determination level of 1, the refrigerant leakage can be notified at an appropriate timing in consideration of the danger due to the model of the indoor unit 22.

  Moreover, since the determination level with the earlier leak detection timing of the determination level according to the installation information and the determination level according to the model is finally determined as the determination level of 1, the detection of leakage is delayed. It is possible to prevent the refrigerant from being ignited.

  Further, when determining the determination level according to the installation information, the determination unit 212 uses the installation information (the semi-underground height H, the bottom area A, and the refrigerant filling) as a risk index K indicating the level of danger at the time of refrigerant leakage. The determination level is determined from the degree of the allowable refrigerant leakage amount until the calculated risk index K exceeds the predetermined reference value Kth (S302, S303). Therefore, an appropriate determination level according to the installation environment and the refrigerant charging amount can be determined. As a result, it is possible to prevent the leakage detection timing from becoming unnecessarily fast and causing inconvenience to the user.

[Modification]
(1) In the above embodiment, the refrigerant leakage detection logic is a logic that compares the temperature difference between the suction temperature of the heat exchanger functioning as an evaporator and the evaporation temperature with a determination level. It is not limited to. For example, the temperature of the refrigerant near the inlet of the heat exchanger functioning as an evaporator is adopted as the first temperature T1, the temperature of the refrigerant just after passing through the expansion mechanism 26 is adopted as the second temperature T2, and both temperatures The logic which detects refrigerant | coolant leakage using may be sufficient.

  In this modification, the temperature sensor 401 may be employed as the first temperature sensor 230 and the temperature sensor 402 may be employed as the second temperature sensor 240 during cooling. In this modification, the temperature sensor 403 may be employed as the first temperature sensor 230 and the temperature sensor 404 may be employed as the second temperature sensor 240 during heating.

  If the refrigerant leakage amount is large at the time of cooling, the evaporation temperature measured by the temperature sensor 401 is difficult to decrease to the target temperature. Therefore, the controller 200 controls, for example, the expansion mechanism 26 in the closing direction to control the indoor heat exchanger. 27 continues to lower the pressure of the refrigerant entering. Therefore, the second temperature T2 measured by the temperature sensor 402 decreases as the refrigerant leakage amount increases. On the other hand, the first temperature T1 measured by the temperature sensor 401 tends to be affected by the indoor air as the refrigerant leakage amount increases, and thus approaches the suction temperature. Therefore, the temperature difference ΔT obtained by subtracting the second temperature T2 from the first temperature T1 increases as the refrigerant leakage amount increases, and the degree of the refrigerant leakage amount can be estimated from the temperature difference ΔT.

  Further, if the refrigerant leakage amount is large during heating, the evaporation temperature measured by the temperature sensor 403 is less likely to decrease to the target temperature. Therefore, the controller 200 controls the expansion mechanism 26 in the closing direction so that the outdoor heat exchanger is closed. Continue to lower the pressure of the refrigerant entering 25. Therefore, the second temperature T2 measured by the temperature sensor 404 decreases as the refrigerant leakage amount increases. On the other hand, the first temperature T1 measured by the temperature sensor 403 tends to be influenced by outdoor air as the refrigerant leakage amount increases, and thus approaches the suction temperature. Therefore, the temperature difference ΔT obtained by subtracting the second temperature T2 from the first temperature T1 increases as the refrigerant leakage amount increases, and the degree of the refrigerant leakage amount can be estimated from the temperature difference ΔT.

  (2) In the above-described embodiment, as shown in FIG. 6, the plurality of predetermined determination levels are provided with three determination levels. However, the present invention is not limited to this. For example, the number of determination levels may be set to N. In this case, an integer greater than or equal to 2 can be adopted as N, and a value that can be regarded as an infinite stage may be adopted. By increasing the value of N, the determination level corresponding to the installation information can be determined more finely.

  (3) In the flowchart of FIG. 3, first, the determination level according to the installation information of the outdoor unit 21 is determined before the determination level according to the model of the indoor unit 22, but this order is reversed. Also good. In this case, the processes of S301 to S304 may be executed after the processes of S305 to S307 are executed.

  (4) In the present embodiment, among the determination level according to the type of the indoor unit 22 and the determination level according to the installation information of the outdoor unit 21, the determination level with the earlier leak detection timing is finally set to 1. Although the determination level is determined, the present invention is not limited to this. For example, the determination level of 1 may be finally determined considering only the installation information of the outdoor unit 21, or the determination level of 1 may be determined finally considering only the type of the indoor unit 22. May be.

  (5) In the present embodiment, the detection unit 214 has been described as notifying the refrigerant leakage when the refrigerant leakage is detected (S406 in FIG. 4), but the present invention is not limited to this, and the refrigerant leakage notification is made. In addition, the air conditioner 2 may be abnormally stopped. Alternatively, when detecting the refrigerant leakage, the detection unit 214, instead of notifying the refrigerant leakage, abnormally stops the air conditioner 2 and stores an abnormality history indicating that the refrigerant leakage has occurred in the storage device. Also good. In this case, the occurrence of the refrigerant leakage can be indicated by referring to the abnormality history without notifying the refrigerant leakage.

DESCRIPTION OF SYMBOLS 2 Air conditioning apparatus 2C Refrigerant circuit 21 Outdoor unit 22 Indoor unit 200 Controller 210 Control part 211 Acquisition part 212 Determination part 213 Estimation part 214 Detection part 220 Storage part 221 Installation information storage part 222 Identification information storage part 223 Determination level storage part 230 1st One temperature sensor 240 Second temperature sensor 250 Input device

Claims (4)

An air conditioner (2) in which an indoor unit and an outdoor unit are connected via a refrigerant circuit for circulating a combustible refrigerant,
An acquisition unit (211) for acquiring installation information indicating an installation environment of the outdoor unit;
An estimation unit (213) for estimating the degree of refrigerant leakage from the refrigerant circuit;
One determination level corresponding to the installation information from among a plurality of determination levels with different degrees of refrigerant leakage so that the leakage detection timing is advanced as the risk of refrigerant leakage due to the installation environment of the outdoor unit increases. A determination unit (212) for determining
Air provided with a detection unit (214) for detecting refrigerant leakage by comparing the degree of refrigerant leakage estimated by the estimation unit (213) with the determination level of 1 determined by the determination unit (212) Harmony device.   The determination unit (212) compares the determination level according to the type of the indoor unit with the determination level according to the installation information of the outdoor unit, and adopts the determination level with the earlier leak detection timing. Item 2. The air conditioner according to Item 1.   The air conditioning apparatus according to claim 1 or 2, wherein the installation information includes information indicating a refrigerant filling amount in the refrigerant circuit and a volume of an installation space in which the outdoor unit is installed.   The said detection part (214) alert | reports refrigerant | coolant leakage, when the degree of the refrigerant | coolant leakage amount estimated by the said estimation part (213) reaches | attains the 1 determination level determined by the said determination part (212). Item 4. The air conditioner according to any one of Items 1 to 3.

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