JP5505126B2 - Refrigeration equipment - Google Patents

Description

  The present invention relates to a refrigeration apparatus.

  Conventionally, as in Patent Document 1 (Japanese Patent Laid-Open No. 10-153354), a refrigeration apparatus that is operated with a so-called chargeless refrigerant amount in which a predetermined amount of refrigerant is sealed in a refrigerant circuit in advance has been proposed. In this refrigeration apparatus, the problem of the refrigeration apparatus due to the unknown length of the connecting pipe connecting the indoor unit and the outdoor unit is corrected.

  When installing such a chargeless type refrigeration system, or when replacing an indoor unit or outdoor unit using existing communication piping, the length of the communication piping can be operated with the chargeless refrigerant amount. If it is too long, it is necessary to fill the refrigerant circuit with additional refrigerant. However, it may be difficult for the installer or the like to know the pipe length of the communication pipe, such as when the installation of the refrigeration apparatus is different from the one that is additionally charged with the refrigerant.

  The subject of this invention is providing the refrigeration apparatus which can know the piping length of communication piping easily.

  The refrigeration apparatus according to the first aspect of the present invention includes a refrigerant circuit, an operation control unit, a supercooling degree related value deriving unit, a storage unit, and an estimation processing unit. The refrigerant circuit includes a utilization unit, a heat source unit, and a communication pipe, and is initially filled with a first predetermined amount of refrigerant. The utilization unit has a utilization side heat exchanger. The heat source unit has a heat source side heat exchanger. The communication pipe connects the use unit and the heat source unit. The operation control unit performs pipe length estimation control. Pipe length estimation control is control which controls the superheat degree of the refrigerant | coolant in the exit of the utilization side heat exchanger in cooling operation or the heat source side heat exchanger in heating operation to a positive value. In the pipe length estimation control, the supercooling degree related value deriving unit obtains the supercooling degree related value related to the supercooling degree at the outlet of the heat source side heat exchanger in cooling operation or the use side heat exchanger in heating operation. To derive. The storage unit stores the first pipe length estimation logic and the second pipe length estimation logic. The first pipe length estimation logic is a logic that associates the supercooling degree related value in the first predetermined amount of refrigerant with the pipe length of the communication pipe. The second pipe length estimation logic is a logic that associates the supercooling degree related value in the second predetermined amount of refrigerant larger than the first predetermined amount with the pipe length of the communication pipe. The estimation processing unit performs a first pipe length estimation process or a second pipe length estimation process. The first pipe length estimation process is a process for estimating the pipe length of the connection pipe based on the supercooling degree related value and the first pipe length estimation logic. The second pipe length estimation process is a process for estimating the pipe length of the connection pipe based on the supercooling degree related value and the second pipe length estimation logic.

  According to the refrigeration apparatus according to the first aspect, pipe length estimation processing for two types of refrigerant amounts can be performed based on the first pipe length estimation logic and the second pipe length estimation logic. For this reason, for example, when it is impossible to estimate the pipe length in the initial refrigerant amount, the pipe length estimation control in the second predetermined amount of refrigerant that is larger than the first predetermined amount of refrigerant initially charged in the refrigerant circuit. The second pipe length estimation process based on the second pipe length estimation logic can be performed. Therefore, for example, even if it is impossible to estimate the pipe length based on the first pipe length estimation process, the pipe length can be estimated by performing the second pipe length estimation process.

  The refrigeration apparatus according to the second aspect of the present invention is the refrigeration apparatus according to the first aspect, further comprising a determination unit and a notification unit. The determination unit determines that it is impossible to estimate the pipe length by the first pipe length estimation logic when the supercooling degree related value derived in the first pipe length estimation process is equal to or less than a predetermined value. When the determination unit determines that estimation of the pipe length is not possible with the first pipe length estimation logic, the notification unit notifies the user to add refrigerant so that the refrigerant amount in the refrigerant circuit becomes the second predetermined amount. Do.

  According to the refrigeration apparatus according to the second aspect, when the supercooling degree related value derived in the first pipe length estimation logic pipe estimation process is equal to or less than the predetermined value, the pipe length estimation is the first pipe length estimation. It is determined that this is impossible with logic, and a notification to that effect is given. For this reason, when it is impossible to estimate the pipe length in the initial refrigerant amount, the pipe length estimation control is performed for the second predetermined amount of refrigerant that is larger than the first predetermined amount of refrigerant initially charged in the refrigerant circuit. In order to perform the notification, for example, it is possible to notify the installer or the like to add the refrigerant so that the refrigerant amount in the refrigerant circuit is the second predetermined amount.

  In the refrigeration apparatus according to the third aspect of the present invention, in the refrigeration apparatus according to the second aspect, the notification unit is a display unit that visually displays the content of the notification.

  Therefore, for example, it is possible to visually notify the installer or the like so that the refrigerant amount in the refrigerant circuit becomes the second predetermined amount.

  In the refrigeration apparatus according to the fourth aspect of the present invention, in the refrigeration apparatus according to the second aspect or the third aspect, the notifying unit is connected to the piping of the connection pipe estimated in the first pipe length estimation process or the second pipe length estimation process. Further inform the length.

  Therefore, for example, the pipe length of the connection pipe can be notified to the installer or the like. For this reason, it is not necessary for the installer or the like to measure the pipe length of the connecting pipe in advance, and the burden on the installer or the like can be reduced.

  The refrigeration apparatus according to the fifth aspect of the present invention is the refrigeration apparatus according to any one of the second to fourth aspects, further comprising an additional refrigerant amount calculation unit. The additional refrigerant amount calculation unit calculates an additional refrigerant amount necessary for the refrigerant circuit from the pipe length of the connection pipe estimated in the first pipe length estimation process or the second pipe length estimation process. The notification unit further notifies the additional refrigerant amount.

  As described above, according to the refrigeration apparatus according to the fifth aspect, when the first predetermined amount of refrigerant is insufficient with respect to the refrigerant circuit, the additional refrigerant amount necessary for the refrigerant circuit is calculated and notified. It is possible to reduce the labor for the operator to calculate the amount of refrigerant. Moreover, since the additional refrigerant amount is calculated based on the supercooling degree related value and the first pipe length estimation logic or the second pipe length estimation logic, the calculation error can be reduced as compared with the case where the installer or the like calculates.

  The refrigeration apparatus according to the sixth aspect of the present invention is the refrigeration apparatus according to any one of the first to fifth aspects, wherein the supercooling degree related value is an excess at the outlet of the heat source side heat exchanger or the use side heat exchanger. This is a value obtained by dividing the physical quantity corresponding to the degree of cooling by the difference between the condensation temperature of the refrigerant and the outside air temperature.

  In the refrigeration apparatus according to the sixth aspect, for example, during cooling operation, the degree of supercooling or the physical quantity corresponding to the degree of supercooling changes depending on the contamination of the heat source side heat exchanger, the surroundings of the heat source side heat exchanger, or the like It is thought that the condensation temperature of the refrigerant also changes. Therefore, the degree of supercooling or the physical quantity corresponding to the degree of supercooling is divided by the value related to the refrigerant condensing temperature, that is, the difference between the condensing temperature and the outside air temperature to calculate the value related to the degree of supercooling. In addition, it is possible to suppress as much as possible that the determination result of the suitability of the refrigerant amount is influenced by the contamination of the heat source side heat exchanger during cooling operation, the situation around the heat source side heat exchanger, and the like.

  The refrigeration apparatus according to a seventh aspect of the present invention is the refrigeration apparatus according to any one of the first to fifth aspects, wherein the supercooling degree related value is a supercooling degree related value at the first time point. In the comparison of the second supercooling degree related value and the second supercooling degree related value that is the second supercooling degree related value that is the supercooling degree related value at the second time point, It is a value corrected by the circulation amount of the refrigerant at two time points and the heat passage rate of the heat source side heat exchanger in the cooling operation or the use side heat exchanger in the heating operation.

  In the refrigeration apparatus according to the seventh aspect, the first supercooling degree related value and the second supercooling degree related value are represented by the refrigerant circulation amount at the first time point and the second time point, and the heat source side heat exchanger or heating during the cooling operation. The suitability of the refrigerant amount in the refrigerant circuit at the second time point is determined by comparing the corrected second subcooling degree related value derived by correcting the heat passage rate of the use side heat exchanger during operation. To do. Thereby, estimation of the pipe length at the second time point can be performed easily and more accurately.

  The refrigeration apparatus according to the eighth aspect of the present invention is the refrigeration apparatus according to any one of the first aspect to the seventh aspect, wherein the communication pipe is an existing pipe.

  In the refrigeration apparatus according to the eighth aspect, since the connecting pipe is an existing pipe, it is difficult for a builder or the like to grasp the pipe length of the connecting pipe. Even in such a refrigeration apparatus, the installer can recognize the pipe length of the communication pipe without measuring the pipe length.

  In the air conditioning apparatus according to the first aspect of the present invention, pipe length estimation processing for two types of refrigerant amounts can be performed based on the first pipe length estimation logic and the second pipe length estimation logic. For this reason, for example, when it is impossible to estimate the pipe length in the initial refrigerant amount, the pipe length estimation control in the second predetermined amount of refrigerant that is larger than the first predetermined amount of refrigerant initially charged in the refrigerant circuit. The second pipe length estimation process based on the second pipe length estimation logic can be performed. Therefore, for example, even if it is impossible to estimate the pipe length based on the first pipe length estimation process, the pipe length can be estimated by performing the second pipe length estimation process.

  In the air conditioning apparatus according to the second aspect of the present invention, when the supercooling degree related value derived during the first pipe length estimation logic pipe estimation process is equal to or less than a predetermined value, the first pipe length estimation logic uses the pipe. It is determined that the length cannot be estimated, and a notification to that effect is given. For this reason, when it is impossible to estimate the pipe length in the initial refrigerant amount, the pipe length estimation control is performed for the second predetermined amount of refrigerant that is larger than the first predetermined amount of refrigerant initially charged in the refrigerant circuit. In order to perform the notification, for example, it is possible to notify the installer or the like to add the refrigerant so that the refrigerant amount in the refrigerant circuit is the second predetermined amount.

  In the air conditioning apparatus according to the third aspect of the present invention, it is possible to visually notify, for example, a contractor or the like so that the refrigerant amount of the refrigerant circuit becomes the second predetermined amount.

  In the air conditioner according to the fourth aspect of the present invention, for example, the length of the communication pipe can be notified to a contractor or the like. For this reason, it is not necessary for the installer or the like to measure the pipe length of the connecting pipe in advance, and the burden on the installer or the like can be reduced.

  In the air conditioning apparatus according to the fifth aspect of the present invention, when the first predetermined amount of refrigerant is insufficient with respect to the refrigerant circuit, the additional refrigerant amount is calculated and notified for calculating the additional refrigerant amount necessary for the refrigerant circuit. It is possible to reduce the time and labor for the installer to calculate. Moreover, since the additional refrigerant amount is calculated based on the supercooling degree related value and the first pipe length estimation logic or the second pipe length estimation logic, the calculation error can be reduced as compared with the case where the installer or the like calculates.

  In the air conditioning apparatus according to the sixth aspect of the present invention, the degree of supercooling or the physical quantity corresponding to the degree of supercooling is divided by the value associated with the refrigerant condensing temperature, that is, the value of the difference between the condensing temperature and the outside air temperature. By calculating the value related to the degree of supercooling, it is as much as possible that the judgment result of the refrigerant quantity is affected by the contamination of the heat source side heat exchanger during cooling operation and the surrounding conditions of the heat source side heat exchanger, etc. Can be suppressed.

  In the air conditioner according to the seventh aspect of the present invention, it is possible to easily and more accurately estimate the pipe length at the second time point.

  In the air conditioner according to the eighth aspect of the present invention, the builder or the like can recognize the pipe length of the connection pipe without the builder measuring the pipe length.

The system diagram of the refrigerant circuit of an air conditioning apparatus. The control block diagram of a control part. The 1st regression type and the 2nd regression type which show the relation between relative supercooling degree and pipe length. The flowchart of piping length estimation control. The flowchart of piping length estimation control. The figure which shows the pattern of lighting and light extinction of LED. The control block diagram of the control part concerning the modification A. FIG. 9 is a system diagram of a refrigerant circuit of an air-conditioning apparatus according to Modification F.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The following embodiments are specific examples of the present invention and do not limit the technical scope of the present invention.

(1) Configuration of Air Conditioner 1 First, the configuration of the air conditioner 1 will be described.

  The air conditioner 1 is a device used for indoor air conditioning by performing a vapor compression refrigeration cycle operation. As shown in FIG. 1, the air conditioner 1 mainly includes a single outdoor unit 2, an indoor unit 4, and a refrigerant communication pipe 8 that connects the outdoor unit 2 and the indoor unit 4. That is, the vapor compression refrigerant circuit 10 of the air conditioner 1 is configured by connecting the outdoor unit 2, the indoor unit 4, and the refrigerant communication pipe 8. Here, the refrigerant communication pipe 8 has a liquid refrigerant communication pipe 6 and a gas refrigerant communication pipe 7. Here, the air conditioner 1 is an air conditioner that is operated with a so-called chargeless refrigerant amount in which a predetermined amount of refrigerant is filled in the outdoor unit 2 in advance.

(1-1) Indoor unit 4
The indoor unit 4 is installed by being embedded or suspended in the ceiling of the room or by hanging on the wall surface of the room. The indoor unit 4 is connected to the outdoor unit 2 via the refrigerant communication pipe 8 and constitutes a part of the refrigerant circuit 10.

  The indoor unit 4 mainly has an indoor refrigerant circuit 11 that constitutes a part of the refrigerant circuit 10. The indoor side refrigerant circuit 11 mainly has an indoor heat exchanger 41 as a use side heat exchanger.

  The indoor heat exchanger 41 is a cross fin type fin-and-tube heat exchanger composed of heat transfer tubes and a large number of fins, and functions as a refrigerant evaporator during cooling operation to cool indoor air. It is a heat exchanger that functions as a refrigerant condenser and heats indoor air during heating operation.

  The indoor unit 4 has an indoor fan 42. The indoor fan 42 is a blower fan for sucking indoor air into the indoor unit 4 and exchanging heat with the refrigerant in the indoor heat exchanger 41 and then supplying the air into the room as supply air. The indoor fan 42 is a fan capable of changing the air volume of air supplied to the indoor heat exchanger 41, and is a centrifugal fan or a multiblade fan driven by a motor 42a formed of a DC fan motor or the like.

  The indoor unit 4 is provided with an indoor temperature sensor 44 that detects the indoor temperature, which is the temperature of the indoor air flowing into the indoor unit 4, on the indoor air inlet side of the indoor unit 4. The indoor temperature sensor 44 is a thermistor.

(1-2) Outdoor unit 2
The outdoor unit 2 is installed outside and is connected to the indoor unit 4 via the refrigerant communication pipe 8 and constitutes the refrigerant circuit 10 together with the indoor unit 4.

  The outdoor unit 2 mainly has an outdoor refrigerant circuit 20 that constitutes a part of the refrigerant circuit 10. The outdoor refrigerant circuit 20 mainly includes a compressor 21, a four-way switching valve 22, an outdoor heat exchanger 23 as a heat source side heat exchanger, an accumulator 24, an outdoor expansion valve 28 as an expansion mechanism, A liquid side closing valve 25 and a gas side closing valve 26 are provided.

  The compressor 21 is a compressor whose operating capacity can be varied, and is a positive displacement compression type in which the rotation speed is controlled by an inverter. In the present embodiment, only one compressor 21 is used. However, the present invention is not limited to this, and two or more compressors 21 may be connected.

  The four-way switching valve 22 is a valve for switching the flow direction of the refrigerant. During the cooling operation, the outdoor heat exchanger 23 is used as a refrigerant condenser compressed by the compressor 21 and the indoor heat exchanger 41 is used. In order to function as an evaporator for the refrigerant condensed in the outdoor heat exchanger 23, the discharge side of the compressor 21 and the gas side of the outdoor heat exchanger 23 are connected and the suction side (specifically, the compressor 21). The accumulator 24) is connected to the gas refrigerant communication pipe 7 side (see the solid line of the four-way switching valve 22 in FIG. 1). Further, the four-way switching valve 22 is configured such that, during the heating operation, the indoor heat exchanger 41 is used as a refrigerant condenser compressed by the compressor 21 and the outdoor heat exchanger 23 is condensed in the indoor heat exchanger 41. In order to function as an evaporator, the discharge side of the compressor 21 and the gas refrigerant communication pipe 7 side are connected, and the suction side of the compressor 21 and the gas side of the outdoor heat exchanger 23 are connected (FIG. 1). (Refer to the broken line of the four-way switching valve 22).

  The outdoor heat exchanger 23 is a cross-fin type fin-and-tube heat exchanger composed of heat transfer tubes and a large number of fins, and functions as a refrigerant condenser during cooling operation and refrigerant during heating operation. It is a heat exchanger that functions as an evaporator. The outdoor heat exchanger 23 has a gas side connected to the four-way switching valve 22 and a liquid side connected to the liquid refrigerant communication pipe 6.

  The accumulator 24 is connected between the four-way selector valve 22 and the compressor 21 and is a container capable of storing surplus refrigerant generated in the refrigerant circuit 10 in accordance with fluctuations in the operating load of the indoor unit 4. It is.

  The outdoor expansion valve 28 is downstream of the outdoor heat exchanger 23 in the refrigerant flow direction in the refrigerant circuit 10 when performing a cooling operation in order to adjust the pressure and flow rate of the refrigerant flowing in the outdoor refrigerant circuit 20. It is also possible to block the passage of the refrigerant.

  The liquid side shutoff valve 25 and the gas side shutoff valve 26 are valves provided at a connection port with an external device or the refrigerant communication pipe 8. The liquid side closing valve 25 is connected to the outdoor heat exchanger 23. The gas side closing valve 26 is connected to the four-way switching valve 22. Further, the liquid side shutoff valve 25 and the gas side shutoff valve 26 have a function of sealing the refrigerant initially filled in the indoor unit 2. In general, when installing the air conditioner 1, the installer or the like connects the indoor unit 4 and the outdoor unit 2 by the refrigerant communication pipe 8 on the site to complete the refrigerant circuit 10. After completing the refrigerant circuit 10, The liquid side closing valve 25 and the gas side closing valve 26 are manually opened. Thereby, the refrigerant sealed in the outdoor unit 2 spreads to the refrigerant circuit 10.

  The outdoor unit 2 has an outdoor fan 27. The outdoor fan 27 is a blower fan for sucking outdoor air into the outdoor unit 2, exchanging heat with the refrigerant in the outdoor heat exchanger 23, and then discharging the air outside. The outdoor fan 27 is a fan capable of changing the air volume of air supplied to the outdoor heat exchanger 23, and is a propeller fan driven by a motor 27a composed of a DC fan motor or the like.

  The outdoor unit 2 is provided with various sensors. Specifically, an evaporating pressure sensor 29 for detecting the evaporating pressure of the gas refrigerant flowing from the indoor heat exchanger 41, a condensing pressure sensor 30 for detecting the condensing pressure Pc condensed by the outdoor heat exchanger 23, and compression An intake temperature sensor 31 for detecting the intake temperature of the machine 21 and an outlet temperature sensor 32 for detecting the temperature of the refrigerant in the liquid state or the gas-liquid two-phase state on the liquid side (outlet side of the refrigerant) of the outdoor heat exchanger 23. Is provided. The outdoor unit 2 is provided with an outdoor temperature sensor 33 that detects the temperature of the outdoor air that flows into the outdoor unit 2.

  As described above, the indoor refrigerant circuit 11, the outdoor refrigerant circuit 20, and the refrigerant communication pipe 8 are connected to constitute the refrigerant circuit 10 of the air conditioner 1.

(2) Control of Air Conditioner 1 Next, control of the air conditioner 1 will be described.

  The control unit 9 is configured using a microcomputer having a CPU, a memory, and the like. The control unit 9 controls various devices such as the indoor unit 4 and the outdoor unit 2. Specifically, as shown in FIG. 2, the control unit 9 is electrically connected to various sensors 29 to 33, 44, the compressor 21, the outdoor expansion valve 28, the LEDs 80a to 80d, and the like. While receiving the detection signals of the sensors 29 to 33 and 44, based on these detection signals, the rotational speed of the compressor 21 is controlled, the opening degree of the outdoor expansion valve 28 is adjusted, and the LEDs 80a to 80d are displayed. Or control.

  The control unit 9 mainly includes an operation control unit 9a, a supercooling degree derivation unit 9b, a storage unit 9c, an estimation processing unit 9d, and a determination unit 9e.

  The operation control unit 9a controls the various devices 21 and 28 based on the detection signals of the various sensors 29 to 23 and 44 in the normal operation mode and the pipe length estimation control mode described later of the air conditioner 1.

  The supercooling degree deriving unit 9b derives the relative supercooling degree SC 'as the supercooling degree related value from the condensation pressure Pc, the outlet temperature Tl, and the outdoor temperature Ta. Specifically, the supercooling degree deriving unit 9b converts the condensation pressure Pc detected by the condensation pressure sensor 30 into the saturation temperature of the refrigerant, and derives the condensation temperature Tc. Then, the supercooling degree deriving unit 9b derives the supercooling degree SC by subtracting the outlet temperature Tl from the derived condensation temperature Tc (SC = Tc−Tl). Then, the supercooling degree deriving unit 9b derives the relative supercooling degree SC ′ by dividing the supercooling degree SC by the value obtained by subtracting the outdoor temperature Ta from the condensation temperature Tc (SC ′ = SC / Tc−Ta). .

  In the storage unit 9c, a regression equation (hereinafter referred to as a first pipe length estimation logic) showing the relationship between the relative supercooling degree SC ′ and the pipe length of the refrigerant communication pipe 8 at the first predetermined amount that is the amount of refrigerant initially charged. (Refer to the solid line in FIG. 3) and the relationship between the relative supercooling degree SC ′ and the pipe length of the refrigerant communication pipe 8 in the second predetermined amount obtained by adding 0.5 kg to the first predetermined amount. Is stored as a regression equation (hereinafter referred to as a second regression equation) (see the broken line in FIG. 3). The second predetermined amount is an amount obtained by adding 0.5 kg to the first predetermined amount in the present embodiment, but is not limited thereto, and may be an amount obtained by adding, for example, 0.3 kg or 1.0 kg. The first regression equation and the second regression equation are equations for determining the pipe length of the refrigerant communication pipe 8 based on the relative subcooling degree SC ′ derived under predetermined conditions in the pipe length estimation control described later. This is an expression created on the assumption of the size of standard piping manufactured based on a predetermined standard.

  The estimation processing unit 9d performs a first pipe length estimation process and a second pipe length estimation process in the pipe length estimation control mode. The first pipe length estimation process is a process for estimating the pipe length of the refrigerant communication pipe 8 in the first predetermined amount of refrigerant based on the relative supercooling degree SC ′ and the first regression equation. The second pipe length estimation process is a process of estimating the pipe length of the refrigerant communication pipe 8 in the second predetermined amount of refrigerant based on the relative supercooling degree SC ′ and the second regression equation.

  The determination unit 9e determines whether the pipe length can be estimated in the first regression equation based on the relative supercooling degree SC ′ in the pipe length estimation control mode. Specifically, the determination unit 9e determines that the pipe length can be estimated in the first regression equation when the relative supercooling degree SC ′ exceeds a predetermined value, and the relative supercooling degree SC ′ is equal to or less than the predetermined value. If it is, it is determined that the pipe length cannot be estimated in the first regression equation.

(3) Operation of Air Conditioner 1 Next, the operation of the air conditioner 1 will be described. These operations are performed by the control unit 9.

  As operation modes of the air conditioner 1, there are mainly a normal operation mode and a pipe length estimation control mode. The normal operation mode includes a cooling operation and a heating operation. In the cooling operation and the heating operation, various devices of the outdoor unit 2 and the indoor unit 4 are controlled according to the operation load of the indoor unit 4. In the pipe length estimation control mode, the condenser circuit 10 is placed in the cooling operation state, and the superheat degree SH of the refrigerant at the outlet of the indoor heat exchanger 41 functioning as an evaporator is controlled to be a constant positive value, while the condenser is The subcooling degree SC of the refrigerant at the outlet of the outdoor heat exchanger 23 functioning as is detected, and the control described later is performed. Here, the superheat degree SH of the refrigerant is controlled to a constant positive value, but the present invention is not limited to this, and it may be controlled only to be a positive value.

  Hereinafter, the operation | movement in each operation mode of the air conditioning apparatus 1 is demonstrated.

(3-1) Normal Operation Mode (3-1-1) Cooling Operation First, the cooling operation in the normal operation mode will be described with reference to FIG.

  During the cooling operation, the four-way switching valve 22 is in the state indicated by the solid line in FIG. 1, that is, the discharge side of the compressor 21 is connected to the gas side of the outdoor heat exchanger 23 and the suction side of the compressor 21 is the indoor heat. It is in a state connected to the gas side of the exchanger 41.

  When the compressor 21 and the outdoor fan 27 are activated, the low-pressure gas refrigerant is sucked into the compressor 21 and compressed to become a high-pressure gas refrigerant. Thereafter, the high-pressure gas refrigerant is sent to the outdoor heat exchanger 23 via the four-way switching valve 22 and is condensed by exchanging heat with the outdoor air supplied by the outdoor fan 27. Become. The high-pressure liquid refrigerant is decompressed by the outdoor expansion valve 28 to become a low-pressure gas-liquid two-phase refrigerant, and is sent to the indoor unit 4 via the liquid-side closing valve 25 and the liquid refrigerant communication pipe 6.

  The low-pressure gas-liquid two-phase refrigerant sent to the indoor unit 4 is sent to the indoor heat exchanger 41 where it is evaporated by exchanging heat with the indoor air in the indoor heat exchanger 41 to become a low-pressure gas refrigerant. . And the refrigerant | coolant of the flow volume according to the driving | running load requested | required in the room | chamber interior in which the indoor unit 4 was installed flows into the indoor heat exchanger 41. FIG.

  This low-pressure gas refrigerant is sent to the outdoor unit 2 via the gas refrigerant communication pipe 7 and flows into the accumulator 24 via the gas-side closing valve 26 and the four-way switching valve 22. Then, the low-pressure gas refrigerant that has flowed into the accumulator 24 is again sucked into the compressor 21. For example, when the operation load of the indoor unit 4 is small or when the operation of the indoor unit 4 is stopped, surplus refrigerant is accumulated in the accumulator 24.

(3-1-2) Heating operation Next, the heating operation in the normal operation mode will be described.

  During the heating operation, the four-way switching valve 22 is in the state indicated by the broken line in FIG. 1, that is, the discharge side of the compressor 21 is connected to the gas side of the indoor heat exchanger 41, and the suction side of the compressor 21 is the outdoor heat. It is connected to the gas side of the exchanger 23. The opening of the outdoor expansion valve 28 is adjusted to reduce the refrigerant flowing into the outdoor heat exchanger 23 to an evaporation pressure at which the refrigerant can be evaporated in the outdoor heat exchanger 23.

  When the compressor 21 and the outdoor fan 27 are activated, the low-pressure gas refrigerant is sucked into the compressor 21 and compressed to become a high-pressure gas refrigerant, and the four-way switching valve 22, the gas-side closing valve 26, and the gas refrigerant communication. It is sent to the indoor unit 4 via the pipe 7.

  The high-pressure gas refrigerant sent to the indoor unit 4 is condensed by exchanging heat with indoor air in the indoor heat exchanger 41, and then becomes high-pressure liquid refrigerant. Sent to the outdoor unit 2. And the refrigerant | coolant of the flow volume according to the driving | running load requested | required in the room | chamber interior in which the indoor unit 4 was installed flows into the indoor heat exchanger 41. FIG.

  The high-pressure liquid refrigerant is reduced in pressure by the outdoor expansion valve 28 via the liquid-side closing valve 25, becomes a low-pressure gas-liquid two-phase refrigerant, and flows into the outdoor heat exchanger 23. The low-pressure gas-liquid two-phase refrigerant that has flowed into the outdoor heat exchanger 23 exchanges heat with the outdoor air supplied by the outdoor fan 27 to evaporate into a low-pressure gas refrigerant. And flows into the accumulator 24. Then, the low-pressure gas refrigerant that has flowed into the accumulator 24 is again sucked into the compressor 21. Note that, for example, when an excess refrigerant amount is generated in the refrigerant circuit 10 such as when the operation load of the indoor unit 4 is small or when the operation of the indoor unit 4 is stopped, the same as in the cooling operation. The surplus refrigerant is accumulated in the accumulator 24.

(3-2) Pipe length estimation control mode In the pipe length estimation control mode, pipe length estimation control is performed. This pipe length estimation control is performed by a remote controller after a construction person or the like configures the refrigerant circuit 10 by connecting the outdoor unit 2 pre-filled with the refrigerant and the indoor unit 4 via the refrigerant communication pipe 8 at the site. (Not shown) or through a pipe length estimation control switch provided in the control unit 9.

  In addition, the pipe length of the refrigerant | coolant communication pipe | tube 8 which can be drive | operated with the 1st predetermined quantity of refrigerant | coolants initially filled by the outdoor unit 2 shall be 30 m, for example.

  Hereinafter, the procedure of pipe length estimation control will be described with reference to FIGS.

  In step S1, when a pipe length estimation control start command is issued, the refrigerant circuit 10 is in a state (cooling operation state) where the four-way switching valve 22 of the outdoor unit 2 is indicated by a solid line in FIG. Then, the compressor 21 and the outdoor fan 27 are activated, and the various devices of the indoor unit 4 operate under the predetermined conditions (the rotational speed of the compressor 21 is constant and the degree of opening of the outdoor expansion valve 28 is adjusted to adjust the accumulator. The cooling operation is forcibly performed under the condition that the superheat degree of the refrigerant at the inlet of the refrigerant is controlled to be a positive value. Then, after the forced cooling operation is performed for a predetermined time, the process proceeds to the next step S2.

  In step S 2, the condensation pressure Pc on the outlet side of the outdoor heat exchanger 23 detected by the condensation pressure sensor 30, the outlet temperature Tl detected by the outlet temperature sensor 32, and the outdoor temperature Ta detected by the outdoor temperature sensor 33. Are detected. Then, when the condensation pressure Pc, the outlet temperature Tl, and the outdoor temperature Ta are detected, the process proceeds to step S3.

  In step S3, the supercooling degree deriving unit 9b derives the relative supercooling degree SC 'based on the condensation pressure Pc, the outlet temperature Tl, and the outdoor temperature Ta detected in step S2. When the relative supercooling degree SC ′ is derived, the process proceeds to step S4.

  In step S4, it is determined whether or not the relative degree of supercooling SC 'is stable. If it is determined that the relative subcooling degree SC 'is stable, the process proceeds to step S5. If it is not determined that the relative subcooling degree SC' is stable, the process returns to step S2 and is repeated. Here, the stability of the relative degree of supercooling SC ′ means that there is no blurring in the change in the numerical value.

  In step S5, the determination unit 9e determines that the pipe length can be estimated in the first regression equation when the relative supercooling degree SC ′ exceeds a predetermined value, and the relative supercooling degree SC ′ is equal to or less than the predetermined value. In some cases, it is determined that the pipe length cannot be estimated in the first regression equation. Accordingly, the determination unit 9e determines whether the pipe length can be estimated in the first regression equation based on the relative degree of supercooling SC ′. If the relative supercooling degree SC 'is less than or equal to the predetermined value, the process proceeds to step S6. If the relative supercooling degree SC' exceeds the predetermined value, the process proceeds to step S12.

  Here, when the pipe length of the refrigerant communication pipe 8 exceeds 70 m, as shown in FIG. 3, the relative supercooling degree SC ′ is unlikely to decrease with the first predetermined amount of refrigerant, and the pipe length of the refrigerant communication pipe 8 is estimated. It becomes difficult. For this reason, 0.5 kg of refrigerant is added to the refrigerant circuit 10 to set the amount of refrigerant to a second predetermined amount, and the second degree in which the relative supercooling degree SC ′ and the pipe length of the refrigerant communication pipe 8 in the second predetermined amount are associated with each other. A second pipe length estimation process (step S8 to step S11) using a regression equation is performed. By using the second regression equation, the pipe length of the refrigerant communication pipe 8 can be estimated even for the refrigerant circuit 10 in which the pipe length of the refrigerant communication pipe 8 exceeds 70 m.

  In step S6, a display to the effect that 0.5 kg of refrigerant is added to the refrigerant circuit 10 is performed.

  In step S7, the system waits until it recognizes a signal indicating that the addition of 0.5 kg of refrigerant has been completed. For example, specifically, when a contractor or the like operates a pipe length estimation control switch (not shown), a signal notifying that the addition of 0.5 kg of refrigerant has been completed is sent to the control unit 9. Recognize. At this time, the cooling operation started in step S1 is continued.

  In Steps S8 to S11, when the relative supercooling degree SC ′ exceeds a predetermined value in Step S5, the second regression that relates the relative supercooling degree SC ′ and the pipe length of the refrigerant communication pipe 8 in the second predetermined amount. A second pipe length estimation process using the equation is performed.

  In step S8, as in step S2, the condensation pressure Pc on the outlet side of the outdoor heat exchanger 23 detected by the condensation pressure sensor 30, the outlet temperature Tl detected by the outlet temperature sensor 32, and the outdoor temperature sensor 33 are used. The detected outdoor temperature Ta is detected. Then, when the condensation pressure Pc, the outlet temperature Tl, and the outdoor temperature Ta are detected, the process proceeds to step S9.

  In step S9, as in step S3, the supercooling degree deriving unit 9b derives the relative supercooling degree SC 'based on the condensation pressure Pc, the outlet temperature Tl, and the outdoor temperature Ta detected in step S8. When the relative supercooling degree SC ′ is derived, the process proceeds to step S10.

  In step S10, it is determined whether or not the relative supercooling degree SC 'is stable. If it is determined that the relative supercooling degree SC 'is stable, the process proceeds to step S11. If it is not determined that the relative supercooling degree SC' is stable, the process returns to step S8 and is repeated.

  In step S11, the pipe length of the refrigerant communication pipe 8 is estimated from the stable relative supercooling degree SC 'based on the second regression equation stored in the storage unit 9c. Then, the process proceeds to step S13. As described above, the second regression equation is created on the premise of the size of a standard pipe manufactured based on a predetermined standard in the second predetermined amount of refrigerant, and the estimated pipe length is the refrigerant This is the length of the pipe length when the communication pipe 8 is converted into the size of the standard pipe.

  In step S12, when the relative supercooling degree SC ′ exceeds a predetermined value in step S5, the first regression equation that associates the relative supercooling degree SC ′ in the first predetermined amount with the pipe length of the refrigerant communication pipe 8 is used. A first pipe length estimation process is performed. In step S12, the pipe length of the refrigerant communication pipe 8 is estimated from the stable relative supercooling degree SC 'based on the first regression equation stored in the storage unit 9c. Then, the process proceeds to step S13. Note that, as described above, the first regression equation is created on the premise of the size of standard piping manufactured based on a predetermined standard in the first predetermined amount of refrigerant initially filled in the outdoor unit 2. The estimated pipe length is the length of the pipe length when the refrigerant communication pipe 8 is converted into the size of the standard pipe.

  In step S13, the pipe length of the refrigerant communication pipe 8 estimated in step S11 or step S12 is notified by the LEDs 80a to 80d. And piping length estimation control is complete | finished. Here, the notified pipe length of the refrigerant communication pipe 8 is the length of the pipe length when the actual refrigerant communication pipe 8 is converted into the size of the standard pipe. A specific notification method using the LEDs 80a to 80d will be described later.

(3-2-1) Notification Method Using LEDs 80a to 80d For the pipe length notification means of the refrigerant communication pipe 8, four LEDs 80a to 80d are used, and the pipe length of the refrigerant communication pipe 8 is determined by turning on or off the LEDs 80a to 80d. Is expressed. The pipe length is expressed in units of meters (m). Specifically, the LED 80a to 80d represent the pipe length, the LED 80a and the LED 80b represent the tenth digit of the refrigerant communication pipe 8, and the LED 80c and the LED 80d represent the first digit. Is done. For example, as shown in FIG. 6, when the LED 80a is turned off and the LED 80b blinks three times, the tenth digit is represented as 3, the LED 80c is always lit, and the LED 80d is turned on once. When blinking, the numerical value of the 1's place is represented as 6. Therefore, the pipe length of the refrigerant communication pipe 8 represented by these LEDs 80a to 80d is 36 m.

  The blinking display by the LEDs 80a to 80d is performed for 5 seconds after the initial state for 5 seconds (for example, the state in which all the LEDs 80a to 80d are turned on for 2.5 seconds and then turned off for 2.5 seconds).

  Moreover, lighting or extinguishing is repeated every 0.5 seconds. For example, when the numerical value 7 is represented by the LED 80a and the LED 80b, the LED 80b blinks twice after the initial state for 5 seconds. The LED 80b blinks twice when the end point of the initial state for 5 seconds is set to 0 seconds, and is turned on for 0 to 0.5 seconds and turned off for 0.5 to 1 seconds. The light is turned on for 1 to 1.5 seconds, and is turned off for 7 counts (3.5 seconds / 0.5 seconds) between 1.5 and 5 seconds. On the other hand, the LED 80a is lit for 5 seconds, that is, 10 counts (5 seconds / 0.5 seconds) after the initial state for 5 seconds.

  Note that the LEDs 80 a to 80 d are provided in an electrical component unit disposed inside the outdoor unit 2.

(4) Features (4-1)
Conventionally, an air conditioner that is operated with a so-called chargeless refrigerant amount, in which an outdoor unit is filled with a refrigerant in advance, has been proposed.

  When the air conditioner is installed and when an indoor unit or an outdoor unit using the existing refrigerant communication pipe is replaced, the length of the refrigerant communication pipe may not be known by the installer. For this reason, whether the pipe length of the refrigerant communication pipe is a pipe length that can be operated only with the amount of chargeless refrigerant filled in the outdoor unit or longer than a pipe length that can be operated only with the amount of chargeless refrigerant. It is assumed that it is impossible to know. Under this circumstance, the contractor or the like does not have to fill the refrigerant in the outdoor unit, or should the refrigerant be filled, and if the refrigerant should be filled, how much refrigerant should be filled. It is thought that it cannot be known whether it has to be filled.

  Therefore, in the air conditioning apparatus 1 according to the present embodiment, a pipe length estimation control mode is provided so that the pipe length estimation operation in that mode can be performed when the air conditioning apparatus 1 is installed. In this pipe length estimation operation, from the relative subcooling degree SC ′ derived from the condensation temperature Tc, the outdoor temperature Ta, and the outlet temperature Tl based on the first regression equation or the second regression equation stored in advance in the control unit 9. The pipe length of the refrigerant communication pipe 8 is estimated. And the estimated piping length is alert | reported to an installer etc. by the blink display by LED80a-80d.

  Thereby, the installer etc. can know the pipe length of the refrigerant communication pipe 8. Therefore, the installer can know whether the refrigerant should be additionally charged in the outdoor unit 2 or not, and when the refrigerant should be additionally charged in the outdoor unit 2. If the pipe length of the refrigerant communication pipe 8 that can be operated with the chargeless refrigerant quantity is subtracted from the estimated pipe length, it can be known that the refrigerant quantity should be additionally charged by the subtracted length.

(4-2)
Further, when the pipe length of the refrigerant communication pipe exceeds a predetermined length (70 m in the present embodiment), the relative supercooling degree SC ′ is unlikely to decrease with the first predetermined amount of refrigerant as shown in FIG. It becomes difficult to estimate the pipe length of the pipe.

  Therefore, in the air conditioning apparatus 1 according to the present embodiment, it is determined whether or not pipe length estimation (first pipe length estimation processing) is possible for the first predetermined amount of refrigerant that is the amount of refrigerant initially charged, When the first pipe length estimation process is impossible, pipe length estimation (second pipe length estimation process) is performed for the second predetermined amount of refrigerant 0.5 kg larger than the first predetermined amount of refrigerant. The first pipe length estimation process is performed based on a first regression equation that associates the relative supercooling degree SC 'with the first predetermined amount of refrigerant amount and the pipe length of the refrigerant communication pipe 8. The second pipe length estimation process is performed based on a second regression equation that associates the relative supercooling degree SC 'with the second predetermined amount of refrigerant amount and the pipe length of the refrigerant communication pipe 8.

  In this way, by adding 0.5 kg of refrigerant to the refrigerant circuit 10 to set the refrigerant amount to the second predetermined amount and performing the second pipe length estimation process, the refrigerant circuit in which the pipe length of the refrigerant communication pipe 8 exceeds 70 m. Also about 10, the pipe length of the refrigerant communication pipe 8 can be estimated.

(5) Modification (5-1) Modification A
In the above embodiment, only the pipe length of the refrigerant communication pipe 8 is notified, but as shown in FIG. 7, an additional refrigerant amount calculation section 9 f is further provided in the control section 9, and based on the pipe length of the refrigerant communication pipe 8. Then, the additional refrigerant amount necessary for the refrigerant circuit may be calculated, and the calculated additional refrigerant amount may be notified. Specifically, the additional refrigerant amount calculation unit 9f calculates the additional refrigerant amount necessary for the refrigerant circuit 10 based on the pipe length of the refrigerant communication pipe 8 estimated by the estimation processing unit 9d. In the first pipe length estimation process, the additional refrigerant amount calculation unit 9f calculates an optimum refrigerant amount optimum for the refrigerant circuit 10 based on the pipe length of the refrigerant communication pipe 8, and subtracts the first refrigerant amount from the optimum refrigerant amount. Thus, the additional refrigerant amount is calculated. In the second pipe length estimation process, the additional refrigerant amount calculation unit 9f calculates the optimum refrigerant amount based on the pipe length of the refrigerant communication pipe 8, and subtracts the second refrigerant amount from the optimum refrigerant amount. Calculate the quantity.

  In the present modification, the optimum refrigerant amount is calculated based on the pipe length of the refrigerant communication pipe 8, but is not limited to this, and the relative supercooling degree SC ′ derived by the supercooling degree deriving unit 9b. You may calculate based on the optimal refrigerant | coolant amount regression type which linked | related the optimal refrigerant | coolant amount, and relative subcooling degree SC '.

(5-2) Modification B
In the above embodiment, the pipe length of the refrigerant communication pipe 8 is determined based on the relative supercooling degree SC ′, but is not limited to the relative supercooling degree SC ′, and may be a simple supercooling degree SC.

(5-3) Modification C
In the above embodiment, the pipe length of the refrigerant communication pipe 8 is determined based on the relative supercooling degree SC ′, but is not limited to this relative supercooling degree SC ′, and the reference relative supercooling stored in advance at the time of development. It may be determined based on the corrected relative supercooling degree CASC ′ obtained by correcting the degree ASC ′.

  Specifically, the corrected relative supercooling degree CASC ′ is the heat transfer rate Ks of the heat transfer tube of the outdoor heat exchanger 23 at the time of development setting operation (first time point) performed at the time of development to the reference relative supercooling degree ASC ′. And the refrigerant circulation amount Grs in the refrigerant circuit 10 (which are stored in the storage unit 9c during the development setting operation) and the heat transfer tube of the outdoor heat exchanger 23 during the pipe length estimation control (second time point) Is multiplied by a relational expression expressed as a functional expression of the heat passage rate Kb (heat passage rate at the second time point) and the refrigerant circulation amount Grb (the refrigerant circulation amount at the second time point) in the refrigerant circuit 10. calculate. The said relational expression is shown in the following (Formula 1). In the following description, the equation (Equation 1) is referred to as a corrected conversion value Δx.

(Expression 1) Δx = (Grb / Grs) × (Ks / Kb)
(Formula 2) CASC ′ = ASC ′ × (Grb / Grs) × (Ks / Kb)
As described above, by correcting the reference relative supercooling degree ASC ′ using the correction conversion value Δx, the heat transfer rate Kb of the heat transfer tube of the outdoor heat exchanger 23 (condenser) and the refrigerant at the time of pipe length estimation control are obtained. The refrigerant circulation amount Grb in the circuit 10 is approximately the same value as the heat transfer rate Ks of the heat transfer tube of the outdoor heat exchanger 23 (condenser) and the refrigerant circulation amount Grs in the refrigerant circuit 10 during the development setting operation. can do. That is, it is possible to directly compare the corrected relative supercooling degree CASC ′ corrected during the pipe length estimation control and the reference relative supercooling degree ASC ′ during the development setting operation. Therefore, the suitability of the refrigerant amount in the refrigerant circuit 10 can be easily and accurately determined.

(5-4) Modification D
In the above-described embodiment, it has been described that the pipe length of the refrigerant communication pipe 8 is notified to the contractor or the like by display by the LEDs 80a to 80d. However, the present invention is not limited to this, and the pipe length is notified by a sound such as a beep sound. May be. Further, a configuration may be adopted in which a remote controller (not shown) is connected to the control unit 9 and the pipe length is displayed on the remote controller. In addition, a 7-segment display may be attached to the electrical equipment of the outdoor unit 2 to display the pipe length, or during test operation, a personal computer or the like is connected to the control unit 9 with a terminal, and the pipe length is displayed on the screen of the personal computer. You may let them.

(5-5) Modification E
In the above embodiment, the controller 9 estimates that the pipe length of the refrigerant communication pipe 8 is estimated from the relative subcooling degree SC ′ based on the first regression equation or the second regression equation preset in the controller 9. However, the present invention is not limited to the regression equation, and the pipe length is estimated from the relative supercooling degree SC ′ based on a map that determines the pipe length of the refrigerant communication pipe 8 from the relative supercooling degree SC ′. May be. That is, in this case, instead of the first regression equation, the second regression equation is used by using the first map that associates the relative supercooling degree SC ′ and the pipe length of the refrigerant communication pipe 8 with the first predetermined amount of refrigerant. Instead, the second map in which the relative degree of supercooling SC ′ in the second predetermined amount of refrigerant is associated with the pipe length of the refrigerant communication pipe 8 is used.

(5-6) Modification F
In the above embodiment, the supercooling degree deriving unit 9b explained that the condensation pressure Pc of the outdoor heat exchanger 23 detected by the condensation pressure sensor 30 is converted to the saturation temperature of the refrigerant to derive the condensation temperature Tc. The temperature Tc may not be derived from the condensation pressure Pc. For example, as shown in FIG. 8, instead of the condensation pressure sensor 30 for detecting the condensation pressure Pc, a two-phase region temperature sensor 35 capable of detecting the temperature of the two-phase region of the refrigerant is provided in the outdoor heat exchanger 23. Therefore, the supercooling degree deriving unit 9b may directly derive the condensation temperature Tc.

(5-7) Modification G
In the said embodiment, although limited and described to the air conditioning apparatus 1, refrigeration apparatuses other than the air conditioning apparatus 1 may be sufficient. Examples of the refrigeration apparatus other than the air conditioner 1 include a heat pump type water heater.

(5-8) Modification H
In the above embodiment, the pipe length estimation control is performed in the cooling operation state, but is not limited thereto, and may be performed in the heating operation state. In the heating operation state, the indoor heat exchanger functioning as a condenser while controlling the superheat degree SH of the refrigerant at the outlet of the outdoor heat exchanger 23 functioning as an evaporator to a positive value during the heating operation. This is done by detecting the supercooling degree SC of the refrigerant at the outlet 41.

1 Air conditioning equipment (refrigeration equipment)
2 Outdoor unit (heat source unit)
4 Indoor units (units used)
8 Refrigerant communication piping (communication piping)
9a Operation control unit 9b Supercooling degree deriving part (Supercooling degree related value deriving part)
9c Storage unit 9d Estimation processing unit 9e Determination unit 9f Additional refrigerant amount calculation unit 10 Refrigerant circuit 23 Outdoor heat exchanger (heat source side heat exchanger)
80a-80d LED (notification part)

Japanese Patent Laid-Open No. 10-153354

Claims (8)

A utilization unit (4) having a utilization side heat exchanger (41), a heat source unit (2) having a heat source side heat exchanger (23), and a connecting pipe (8) connecting the utilization unit and the heat source unit A refrigerant circuit (10) initially filled with a first predetermined amount of refrigerant;
An operation control unit (9a) for performing pipe length estimation control for controlling the superheat degree of the refrigerant at the outlet of the use side heat exchanger in the cooling operation or the heat source side heat exchanger in the heating operation to a positive value;
In the pipe length estimation control, a supercooling degree related value related to a supercooling degree at the outlet of the heat source side heat exchanger in the cooling operation or the use side heat exchanger in the heating operation is derived. Degree related value deriving section (9b),
A first pipe length estimation logic for associating the supercooling degree related value in the first predetermined amount of refrigerant with the pipe length of the communication pipe; and the excess in the second predetermined amount of refrigerant larger than the first predetermined amount. A storage unit (9c) for storing a second pipe length estimation logic that associates a cooling degree related value and a pipe length of the communication pipe;
A first pipe length estimation process for estimating the pipe length of the communication pipe based on the supercooling degree related value and the first pipe length estimation logic, or the supercooling degree related value and the second pipe length estimation logic. An estimation processing unit (9d) for performing a second pipe length estimation process for estimating the pipe length of the communication pipe based on
A refrigeration apparatus (1). Determining whether or not the first pipe length estimation logic is capable of estimating the pipe length when the supercooling degree related value derived during the first pipe length estimation process is equal to or less than a predetermined value. Part (9e),
When the determination unit determines that estimation of the pipe length is not possible with the first pipe length estimation logic, a notification that prompts the addition of the refrigerant so that the refrigerant amount of the refrigerant circuit becomes the second predetermined amount A notification unit (80a to 80d) to perform;
Further comprising
The refrigeration apparatus (1) according to claim 1. The notification unit is a display unit that visually displays the content of the notification.
The refrigeration apparatus (1) according to claim 2. The notification unit further notifies the pipe length of the communication pipe estimated in the first pipe length estimation process or the second pipe length estimation process.
The refrigeration apparatus (1) according to claim 2 or 3. An additional refrigerant amount calculation unit (9f) that calculates an additional refrigerant amount necessary for the refrigerant circuit based on the pipe length of the communication pipe estimated in the first pipe length estimation process or the second pipe length estimation process. ,
In addition,
The notification unit further notifies the additional refrigerant amount,
The refrigeration apparatus (1) according to any one of claims 2 to 4. The supercooling degree related value is a value obtained by dividing a physical quantity corresponding to the supercooling degree at the outlet of the heat source side heat exchanger or the use side heat exchanger by the difference between the refrigerant condensing temperature and the outside air temperature.
The refrigeration apparatus (1) according to any one of claims 1 to 5. The supercooling degree related value is a comparison between a first supercooling degree related value that is the supercooling degree related value at the first time point and a second supercooling degree related value that is the supercooling degree related value at the second time point. The second subcooling degree related value is obtained by calculating the refrigerant circulation amount at the first time point and the second time point and the heat of the heat source side heat exchanger in the cooling operation or the use side heat exchanger in the heating operation. It is a value corrected by the passage rate.
The refrigeration apparatus (1) according to any one of claims 1 to 5. The connecting pipe is an existing pipe.
The refrigeration apparatus (1) according to any one of claims 1 to 7.

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