JP2006292211A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately determine the suitability of the amount of refrigerants charged in a separate type air conditioner where the outdoor unit is connected to the indoor unit via a refrigerant communication pipe, even when an outdoor heat exchanger or an indoor heat exchanger ages. <P>SOLUTION: The air conditioner 1 comprises a refrigerant circuit 10 constituted by connecting the outdoor unit 2 to the indoor units 4 and 5 via the refrigerant communication pipes 6 and 7, a refrigerant amount determining means, and a state amount correcting means. The refrigerant amount determining means determines the suitability of the refrigerant amount based on the present value of the supercooling degree SC<SB>o</SB>of the refrigerant flowing in the refrigerant circuit 10 or a component apparatus and the reference value of the supercooling degree SC<SB>o</SB>of the refrigerant flowing in the refrigerant circuit 10 or the component apparatus. When the refrigerant amount determining means determines the suitability of the refrigerant amount, the state amount correcting means corrects the supercooling degree SC<SB>o</SB>using the discharge pressure Pd, the outside temperature Ta, the intake pressure Ps, and the inside temperature Tr. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention has a function of determining the suitability of the amount of refrigerant charged in the air conditioner, particularly, a separate type air conditioner in which an outdoor unit and an indoor unit are connected via a refrigerant communication pipe. The present invention relates to a function for determining the suitability of the amount of refrigerant.

  Conventionally, there is a separate type air conditioner in which a refrigerant circuit is configured by connecting an outdoor unit and an indoor unit via a refrigerant communication pipe. In such an air conditioner, the refrigerant may leak from the refrigerant circuit for some reason. Such refrigerant leakage causes a decrease in the air conditioning capability of the air conditioner and damages to the components, and therefore it is desirable to have a function for determining the suitability of the amount of refrigerant charged in the air conditioner.

On the other hand, a method of determining the suitability of the refrigerant amount using the degree of superheat of the refrigerant at the outlet of the outdoor heat exchanger during heating operation or the degree of refrigerant superheat at the outlet of the indoor heat exchanger during cooling operation (Patent Document) 1), a method for determining the suitability of the refrigerant amount using the degree of supercooling at the outlet of the outdoor heat exchanger during cooling operation (see Patent Document 2), and the like.
JP 02-208469 A JP 2000-304388 A

  In the conventional air conditioner having the function of determining the suitability of the refrigerant amount as described above, immediately after an outdoor unit or an indoor unit including an outdoor heat exchanger or an indoor heat exchanger is installed and used in the field. The standard value of the degree of superheat and the degree of supercooling (hereinafter referred to as the operating state quantity) corresponding to the state (for example, the outdoor heat exchanger or the indoor heat exchanger is new), and the current value of the operating state quantity Therefore, it is determined whether or not the refrigerant amount is appropriate.Therefore, fluctuations in the operation state amount due to aging of the outdoor heat exchanger and the indoor heat exchanger are not considered, and as a result, determination of the appropriateness of the refrigerant amount is made. There arises a problem that the accuracy of the is reduced.

  An object of the present invention is to provide a separate type air conditioner in which an outdoor unit and an indoor unit are connected via a refrigerant communication pipe, even if the outdoor heat exchanger or the indoor heat exchanger deteriorates over time. The purpose is to make it possible to accurately determine the suitability of the amount of refrigerant charged.

  An air conditioner according to a first invention is configured by connecting an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger via a refrigerant communication pipe. The air conditioner includes a refrigerant circuit that includes a refrigerant amount determination unit and a state amount correction unit. The refrigerant amount determination means determines whether or not the refrigerant amount is appropriate based on a current value of the operating state quantity of the refrigerant or component device flowing in the refrigerant circuit and a reference value of the operating state quantity of the refrigerant or component device flowing in the refrigerant circuit. . The state quantity correction unit corrects the operation state quantity using the refrigerant pressure or refrigerant temperature in the outdoor heat exchanger and the outside air temperature when the refrigerant quantity judgment unit judges whether or not the refrigerant quantity is appropriate.

  In general, the heat exchange performance of a heat exchanger is determined by a multiplication value of a heat transfer coefficient K and a heat transfer area A (hereinafter referred to as coefficient KA), and this coefficient KA is multiplied by an internal / external temperature difference of the heat exchanger. Determines the amount of heat exchange. Therefore, as long as the coefficient KA is constant, the heat exchange performance of the heat exchanger is the difference between the inside and outside temperature (in the case of an outdoor heat exchanger, the temperature difference between the outside air temperature and the temperature of the refrigerant flowing in the outside heat exchanger). ) Will be determined.

  However, for example, when the outdoor heat exchanger is a cross fin tube type heat exchanger, the coefficient KA varies due to deterioration over time such as contamination of the plate fins and heat transfer tubes and clogging of the plate fins. Actually, it is not a constant value. Specifically, the coefficient KA of the outdoor heat exchanger after the aging deterioration is the outdoor heat exchanger in a state immediately after being installed on the site and starting to be used (for example, the outdoor heat exchanger is a new state). Smaller than the coefficient KA. As described above, when the coefficient KA varies, the correlation between the refrigerant pressure and the refrigerant temperature in the outdoor heat exchanger and the outdoor temperature is determined almost uniquely under the condition that the coefficient KA is constant. The correlation between the refrigerant pressure and the refrigerant temperature in the outdoor heat exchanger and the outside air temperature varies in accordance with the fluctuation of the temperature. For example, under the same outdoor temperature conditions, the refrigerant pressure and refrigerant temperature in an outdoor heat exchanger that has deteriorated over time are the refrigerant pressure and refrigerant in the outdoor heat exchanger in a state immediately after being installed in the field and started to be used. Compared to the temperature, the difference between the inside and outside temperature in the outdoor heat exchanger fluctuates in accordance with the decrease in the coefficient KA. For this reason, when adopting a method for determining the suitability of the refrigerant quantity based on the current value of the operation state quantity and the reference value of the operation state quantity as the refrigerant quantity judgment means, the outdoor heat exchanger deteriorates over time. The current operating state quantity after the operation is compared with the reference value of the operating state quantity in the state immediately after the outdoor heat exchanger is installed and used, and as a result, a different coefficient KA is set. Since the operating state quantities detected in the two air conditioners configured using the outdoor heat exchangers to be compared are compared with each other, the influence of fluctuations in the operating state quantity due to aging deterioration cannot be excluded, and the refrigerant quantity determination It is impossible to accurately determine the suitability of.

  Therefore, in this air conditioner, the coefficient KA of the outdoor heat exchanger varies according to the degree of deterioration over time, that is, the refrigerant pressure, the refrigerant temperature, and the outdoor air temperature in the outdoor heat exchanger with the variation of the coefficient KA. The operational state quantity used in the refrigerant quantity determination means is corrected by using the refrigerant pressure or refrigerant temperature in the outdoor heat exchanger and the outside air temperature. Since the operating state quantities detected in the air conditioner configured using the outdoor heat exchanger having the coefficient KA can be compared with each other, it is possible to eliminate the influence of fluctuations in the operating state quantity due to deterioration over time.

Thereby, in this air conditioning apparatus, even if the outdoor heat exchanger has deteriorated over time, it is possible to accurately determine whether or not the amount of refrigerant charged in the apparatus is appropriate.
An air conditioner according to a second aspect of the invention is configured by connecting an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger via a refrigerant communication pipe. The air conditioner includes a refrigerant circuit that includes a refrigerant amount determination unit and a state amount correction unit. The refrigerant amount determination means determines whether or not the refrigerant amount is appropriate based on a current value of the operating state quantity of the refrigerant or component device flowing in the refrigerant circuit and a reference value of the operating state quantity of the refrigerant or component device flowing in the refrigerant circuit. . The state quantity correction unit corrects the operation state quantity by using the refrigerant pressure or the refrigerant temperature in the indoor heat exchanger and the room temperature when the refrigerant quantity judgment unit determines whether or not the refrigerant quantity is appropriate.

  In general, the heat exchange performance of a heat exchanger is determined by a multiplication value of a heat transfer coefficient K and a heat transfer area A (hereinafter referred to as coefficient KA), and this coefficient KA is multiplied by an internal / external temperature difference of the heat exchanger. Determines the amount of heat exchange. For this reason, as long as the coefficient KA is constant, the heat exchange performance of the heat exchanger is the difference between the internal and external temperature (in the case of an indoor heat exchanger, the temperature difference between the indoor temperature and the temperature of the refrigerant flowing in the indoor heat exchanger). ) Will be determined.

  However, for example, when the indoor heat exchanger is a cross fin tube type heat exchanger, the coefficient KA varies due to deterioration over time such as contamination of the plate fins and heat transfer tubes and clogging of the plate fins. Actually, it is not a constant value. Specifically, the coefficient KA of the indoor heat exchanger after the deterioration over time is the indoor heat exchanger in a state immediately after being installed on the site and starting to be used (for example, the indoor heat exchanger is a new state). Smaller than the coefficient KA. As described above, when the coefficient KA varies, the correlation between the refrigerant pressure and the refrigerant temperature in the indoor heat exchanger and the indoor temperature is almost uniquely determined under the condition that the coefficient KA is constant, whereas the coefficient KA is determined. The correlation between the refrigerant pressure and the refrigerant temperature in the indoor heat exchanger and the room temperature varies according to the fluctuation of the room temperature. For example, under the same indoor temperature conditions, the refrigerant pressure and refrigerant temperature in an indoor heat exchanger that has deteriorated over time are the refrigerant pressure and refrigerant in the indoor heat exchanger in a state immediately after being installed on the site and starting to use. Compared to the temperature, the temperature difference between the inside and outside of the indoor heat exchanger fluctuates in accordance with a decrease in the coefficient KA. For this reason, when adopting a method for determining the appropriateness of the refrigerant quantity based on the current value of the operation state quantity and the reference value of the operation state quantity as the refrigerant quantity judgment means, the indoor heat exchanger deteriorates over time. The current operating state quantity after the operation and the reference value of the operating state quantity in the state immediately after the indoor heat exchanger is installed and used in the field are compared. As a result, a different coefficient KA is set. Since the operation state quantities detected in the two air conditioners configured using the indoor heat exchanger having the same are compared with each other, the influence of the fluctuation of the operation state quantity due to deterioration over time cannot be excluded, and the refrigerant amount determination It is impossible to accurately determine the suitability of.

  Therefore, in this air conditioner, the coefficient KA of the indoor heat exchanger varies according to the degree of deterioration over time, that is, the refrigerant pressure, the refrigerant temperature, and the room temperature in the indoor heat exchanger with the fluctuation of the coefficient KA. The amount of operation state used in the refrigerant amount determination means is corrected by using the refrigerant pressure or refrigerant temperature in the indoor heat exchanger and the room temperature. Since the operating state quantities detected in the air conditioner configured using the indoor heat exchanger having the coefficient KA can be compared with each other, the influence of fluctuations in the operating state quantity due to deterioration over time can be eliminated.

Thereby, in this air conditioning apparatus, even if aged deterioration of the indoor heat exchanger occurs, it is possible to accurately determine the suitability of the refrigerant amount charged in the apparatus.
An air conditioner according to a third aspect of the invention is configured by connecting an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger via a refrigerant communication pipe. The air conditioner includes a refrigerant circuit that includes a refrigerant amount determination unit and a state amount correction unit. The refrigerant amount determination means determines whether or not the refrigerant amount is appropriate based on a current value of the operating state quantity of the refrigerant or component device flowing in the refrigerant circuit and a reference value of the operating state quantity of the refrigerant or component device flowing in the refrigerant circuit. . When the refrigerant quantity determination means determines whether or not the refrigerant quantity is appropriate, the state quantity correction means converts the operation state quantity into the refrigerant pressure or refrigerant temperature in the outdoor heat exchanger, the outdoor air temperature, the refrigerant pressure or refrigerant temperature in the indoor heat exchanger. And the room temperature is used for correction.

  In general, the heat exchange performance of a heat exchanger is determined by a multiplication value of a heat transfer coefficient K and a heat transfer area A (hereinafter referred to as coefficient KA), and this coefficient KA is multiplied by an internal / external temperature difference of the heat exchanger. Determines the amount of heat exchange. Therefore, as long as the coefficient KA is constant, the heat exchange performance of the heat exchanger is the difference between the inside and outside temperature (in the case of an outdoor heat exchanger, the temperature difference between the outside air temperature and the temperature of the refrigerant flowing in the outside heat exchanger). In the case of an indoor heat exchanger, it is determined by the temperature difference between the room temperature and the temperature of the refrigerant flowing in the indoor heat exchanger.

  However, for example, when the outdoor heat exchanger is a cross fin tube type heat exchanger, the coefficient KA varies due to deterioration over time such as contamination of the plate fins and heat transfer tubes and clogging of the plate fins. Actually, it is not a constant value. Specifically, the coefficient KA of the outdoor heat exchanger after the aging deterioration is the outdoor heat exchanger in a state immediately after being installed on the site and starting to be used (for example, the outdoor heat exchanger is a new state). Smaller than the coefficient KA. As described above, when the coefficient KA varies, the correlation between the refrigerant pressure and the refrigerant temperature in the outdoor heat exchanger and the outdoor temperature is determined almost uniquely under the condition that the coefficient KA is constant. The correlation between the refrigerant pressure and the refrigerant temperature in the outdoor heat exchanger and the outside air temperature varies in accordance with the fluctuation of the temperature. For example, under the same outdoor temperature conditions, the refrigerant pressure and refrigerant temperature in an outdoor heat exchanger that has deteriorated over time are the refrigerant pressure and refrigerant in the outdoor heat exchanger in a state immediately after being installed in the field and started to be used. Compared to the temperature, the difference between the inside and outside temperature in the outdoor heat exchanger fluctuates in accordance with the decrease in the coefficient KA. For this reason, when adopting a method for determining the suitability of the refrigerant quantity based on the current value of the operation state quantity and the reference value of the operation state quantity as the refrigerant quantity judgment means, the outdoor heat exchanger deteriorates over time. The current operating state quantity after the operation is compared with the reference value of the operating state quantity in the state immediately after the outdoor heat exchanger is installed and used, and as a result, a different coefficient KA is set. Since the operating state quantities detected in the two air conditioners configured using the outdoor heat exchangers to be compared are compared with each other, the influence of fluctuations in the operating state quantity due to aging deterioration cannot be excluded, and the refrigerant quantity determination It is impossible to accurately determine the suitability of.

  This is also true for indoor heat exchangers, and the refrigerant pressure and refrigerant temperature in the indoor heat exchanger in a state where deterioration has occurred under the same indoor temperature conditions are the same as those immediately after the installation and start of use. Compared to the refrigerant pressure and the refrigerant temperature in the indoor heat exchanger (for example, when the indoor heat exchanger is new), the inside / outside temperature difference in the indoor heat exchanger varies in the direction of expansion as the coefficient KA decreases. Therefore, when adopting a method for determining the suitability of the refrigerant amount based on the current value of the operation state quantity and the reference value of the operation state quantity as the refrigerant quantity determination means, the indoor heat exchanger is subject to deterioration over time. The current operating state quantity after the occurrence is compared with the reference value of the operating state quantity in the state immediately after the indoor heat exchanger is installed and started to be used, and as a result, a different coefficient KA Have Since the operation state quantities detected in the two air conditioners configured using the indoor heat exchanger are compared with each other, the influence of fluctuations in the operation state quantity due to aging cannot be excluded, and the refrigerant amount determination The suitability cannot be accurately determined.

  Therefore, in this air conditioner, the coefficient KA of the outdoor heat exchanger and the indoor heat exchanger varies depending on the degree of deterioration over time, that is, the refrigerant pressure and the refrigerant pressure in the outdoor heat exchanger vary with the variation of the coefficient KA. Paying attention to the correlation between the refrigerant temperature and the outside air temperature and the correlation between the refrigerant pressure in the indoor heat exchanger and the refrigerant temperature and the room temperature, the operating state quantity used in the refrigerant quantity judging means is The outdoor heat exchanger and the indoor heat having the same coefficient KA are corrected by using the refrigerant pressure or refrigerant temperature in the outdoor heat exchanger, the outside air temperature, the refrigerant pressure or refrigerant temperature in the indoor heat exchanger, and the room temperature. Since it is possible to compare operating state quantities detected in an air conditioner configured using an exchanger, it is possible to eliminate the influence of fluctuations in operating state quantities due to aging Kill.

Thereby, in this air conditioning apparatus, even if the outdoor heat exchanger and the indoor heat exchanger are deteriorated over time, it is possible to accurately determine whether or not the amount of refrigerant filled in the apparatus is appropriate.
A refrigerant quantity determination system for an air conditioner according to a fourth aspect of the present invention includes a state quantity acquisition unit, a state quantity storage unit, a refrigerant quantity determination unit, and a state quantity correction unit. The state quantity acquisition means acquires the operating state quantity of the refrigerant or the component device flowing through the refrigerant circuit from the air conditioner. The air conditioner includes a refrigerant circuit configured by connecting an outdoor unit having a compressor and an outdoor heat exchanger and an indoor unit having an indoor heat exchanger via a refrigerant communication pipe. Yes. The state quantity accumulation unit accumulates the operation state quantity acquired by the state quantity acquisition unit as a reference value for the operation state quantity. The refrigerant amount determination unit determines whether the refrigerant amount is appropriate based on the current value of the operation state amount acquired by the state amount acquisition unit and the reference value of the operation state amount stored in the state amount storage unit. When the refrigerant quantity determination means determines whether or not the refrigerant quantity is appropriate, the state quantity correction means converts the operation state quantity into the refrigerant pressure or refrigerant temperature in the outdoor heat exchanger, the outdoor air temperature, the refrigerant pressure or refrigerant temperature in the indoor heat exchanger. And the room temperature is used for correction.

  In general, the heat exchange performance of a heat exchanger is determined by a multiplication value of a heat transfer coefficient K and a heat transfer area A (hereinafter referred to as coefficient KA), and this coefficient KA is multiplied by an internal / external temperature difference of the heat exchanger. Determines the amount of heat exchange. Therefore, as long as the coefficient KA is constant, the heat exchange performance of the heat exchanger is the difference between the inside and outside temperature (in the case of an outdoor heat exchanger, the temperature difference between the outside air temperature and the temperature of the refrigerant flowing in the outside heat exchanger). In the case of an indoor heat exchanger, it is determined by the temperature difference between the room temperature and the temperature of the refrigerant flowing in the indoor heat exchanger.

  However, for example, when the outdoor heat exchanger is a cross fin tube type heat exchanger, the coefficient KA varies due to deterioration over time such as contamination of the plate fins and heat transfer tubes and clogging of the plate fins. Actually, it is not a constant value. Specifically, the coefficient KA of the outdoor heat exchanger after the aging deterioration is the outdoor heat exchanger in a state immediately after being installed on the site and starting to be used (for example, the outdoor heat exchanger is a new state). Smaller than the coefficient KA. As described above, when the coefficient KA varies, the correlation between the refrigerant pressure and the refrigerant temperature in the outdoor heat exchanger and the outdoor temperature is determined almost uniquely under the condition that the coefficient KA is constant. The correlation between the refrigerant pressure and the refrigerant temperature in the outdoor heat exchanger and the outside air temperature varies in accordance with the fluctuation of the temperature. For example, under the same outdoor temperature conditions, the refrigerant pressure and refrigerant temperature in an outdoor heat exchanger that has deteriorated over time are the refrigerant pressure and refrigerant in the outdoor heat exchanger in a state immediately after being installed in the field and started to be used. Compared to the temperature, the difference between the inside and outside temperature in the outdoor heat exchanger fluctuates in accordance with the decrease in the coefficient KA. For this reason, when adopting a method for determining the suitability of the refrigerant quantity based on the current value of the operation state quantity and the reference value of the operation state quantity as the refrigerant quantity judgment means, the outdoor heat exchanger deteriorates over time. The current operating state quantity after the operation is compared with the reference value of the operating state quantity in the state immediately after the outdoor heat exchanger is installed and used, and as a result, a different coefficient KA is set. Since the operating state quantities detected in the two air conditioners configured using the outdoor heat exchangers to be compared are compared with each other, the influence of fluctuations in the operating state quantity due to aging deterioration cannot be excluded, and the refrigerant quantity determination It is impossible to accurately determine the suitability of.

  This is also true for indoor heat exchangers, and the refrigerant pressure and refrigerant temperature in the indoor heat exchanger in a state where deterioration has occurred under the same indoor temperature conditions are the same as those immediately after the installation and start of use. Compared to the refrigerant pressure and the refrigerant temperature in the indoor heat exchanger (for example, when the indoor heat exchanger is new), the inside / outside temperature difference in the indoor heat exchanger varies in the direction of expansion as the coefficient KA decreases. Therefore, when adopting a method for determining the suitability of the refrigerant amount based on the current value of the operation state quantity and the reference value of the operation state quantity as the refrigerant quantity determination means, the indoor heat exchanger is subject to deterioration over time. The current operating state quantity after the occurrence is compared with the reference value of the operating state quantity in the state immediately after the indoor heat exchanger is installed and started to be used, and as a result, a different coefficient KA Have Since the operation state quantities detected in the two air conditioners configured using the indoor heat exchanger are compared with each other, the influence of fluctuations in the operation state quantity due to aging cannot be excluded, and the refrigerant amount determination The suitability cannot be accurately determined.

  Therefore, in this refrigerant quantity determination system, the coefficient KA of the outdoor heat exchanger and the indoor heat exchanger varies according to the degree of aging, that is, the refrigerant pressure in the outdoor heat exchanger varies with the coefficient KA. And the correlation between the refrigerant temperature and the outside air temperature, and the correlation between the refrigerant pressure in the indoor heat exchanger and the correlation between the refrigerant temperature and the room temperature, the operating state quantity used in the refrigerant quantity judging means Is corrected using the refrigerant pressure or refrigerant temperature in the outdoor heat exchanger, the outside air temperature, the refrigerant pressure or refrigerant temperature in the indoor heat exchanger, and the room temperature, and the outdoor heat exchanger and the room having the same coefficient KA Since the operating state quantities detected in the air conditioner configured using a heat exchanger can be compared with each other, the influence of fluctuations in the operating state quantities due to aging is eliminated. Door can be.

Thereby, in this refrigerant | coolant amount determination system, even if aged deterioration of an outdoor heat exchanger and an indoor heat exchanger arises, the suitability of the refrigerant | coolant amount with which the inside of an apparatus is filled can be determined accurately.
The refrigerant amount determination system for an air conditioner according to a fifth aspect of the present invention is the refrigerant amount determination system for an air conditioner according to the fourth aspect of the present invention, wherein the state quantity acquisition means manages the air conditioner. The state quantity storage means, the refrigerant quantity determination means, and the state quantity correction means are remote from the air conditioner and are connected to the state quantity acquisition means via a communication line.

  In this refrigerant quantity determination system, since the state quantity accumulation means, the refrigerant quantity judgment means, and the state quantity correction means exist remotely from the air conditioner, a large amount of past operation data of the air conditioner is accumulated. It is possible to easily realize a configuration that can be set. Thereby, for example, operation data similar to the current operation data acquired by the state quantity acquisition unit is selected from past operation data stored in the storage unit, and both data are compared to determine whether the refrigerant amount is appropriate. Judgment can be made.

As described above, according to the present invention, the following effects can be obtained.
In the first invention, even if the outdoor heat exchanger has deteriorated over time, it is possible to accurately determine whether or not the amount of refrigerant charged in the apparatus is appropriate.
In 2nd invention, even if aged deterioration of an indoor heat exchanger arises, the suitability of the refrigerant | coolant amount with which the inside of an apparatus is filled can be determined accurately.

In 3rd invention, even if aged deterioration of an outdoor heat exchanger and an indoor heat exchanger arises, the suitability of the refrigerant | coolant amount with which the inside of an apparatus is filled can be determined accurately.
In the fourth invention, even if the outdoor heat exchanger and the indoor heat exchanger are deteriorated over time, it is possible to accurately determine the suitability of the amount of refrigerant charged in the air conditioner.
According to the fifth aspect of the invention, a configuration capable of accumulating a large amount of past operation data of the air conditioner can be easily realized.

Hereinafter, embodiments of an air-conditioning apparatus according to the present invention will be described based on the drawings.
(1) Configuration of Air Conditioner FIG. 1 is a schematic refrigerant circuit diagram of an air conditioner 1 according to an embodiment of the present invention. The air conditioner 1 is a device used for indoor air conditioning such as a building by performing a vapor compression refrigeration cycle operation. The air conditioner 1 mainly includes an outdoor unit 2 as one heat source unit, indoor units 4 and 5 as a plurality of (two in the present embodiment) usage units connected in parallel thereto, and an outdoor unit. A liquid refrigerant communication pipe 6 and a gas refrigerant communication pipe 7 are provided as refrigerant communication pipes connecting the unit 2 and the indoor units 4 and 5. That is, the vapor compression refrigerant circuit 10 of the air conditioner 1 of the present embodiment is configured by connecting the outdoor unit 2, the indoor units 4 and 5, the liquid refrigerant communication pipe 6 and the gas refrigerant communication pipe 7. It is configured.

<Indoor unit>
The indoor units 4 and 5 are installed by embedding or hanging on an indoor ceiling of a building or the like, or are installed on a wall surface of the indoor by wall hanging or the like. The indoor units 4 and 5 are connected to the outdoor unit 2 via the liquid refrigerant communication pipe 6 and the gas refrigerant communication pipe 7 and constitute a part of the refrigerant circuit 10.

Next, the configuration of the indoor units 4 and 5 will be described. In addition, since the indoor unit 4 and the indoor unit 5 have the same configuration, only the configuration of the indoor unit 4 will be described here, and the configuration of the indoor unit 5 is the 40th number indicating each part of the indoor unit 4. The reference numerals in the 50s are attached instead of the reference numerals, and description of each part is omitted.
The indoor unit 4 mainly includes an indoor refrigerant circuit 10a (in the indoor unit 5, the indoor refrigerant circuit 10b) that constitutes a part of the refrigerant circuit 10. The indoor refrigerant circuit 10a mainly includes an indoor expansion valve 41 as a use side expansion valve and an indoor heat exchanger 42 as a use side heat exchanger.

In the present embodiment, the indoor expansion valve 41 is an electric expansion valve connected to the liquid side of the indoor heat exchanger 42 in order to adjust the flow rate of the refrigerant flowing in the indoor refrigerant circuit 10a.
In the present embodiment, the indoor heat exchanger 42 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. It is a heat exchanger that cools indoor air and functions as a refrigerant condenser during heating operation to heat indoor air.

  In the present embodiment, the indoor unit 4 includes an indoor fan 43 for supplying indoor air as supply air after sucking indoor air into the unit and exchanging heat, and the indoor air and indoor heat exchanger 42 are provided. It is possible to exchange heat with the refrigerant flowing through The indoor fan 43 is a fan capable of changing the flow rate of air supplied to the indoor heat exchanger 42. In the present embodiment, the indoor fan 43 is a centrifugal fan or a multiblade fan driven by a motor 43a composed of a DC fan motor. It is.

  The indoor unit 4 is provided with various sensors. On the liquid side of the indoor heat exchanger 42, the temperature of the refrigerant in the liquid state or the gas-liquid two-phase state (that is, the refrigerant temperature corresponding to the condensation temperature Tc during the heating operation or the evaporation temperature Te during the cooling operation) is detected. A liquid side temperature sensor 44 is provided. A gas side temperature sensor 45 that detects the temperature of the refrigerant in the gas state or the gas-liquid two-phase state is provided on the gas side of the indoor heat exchanger 42. An indoor temperature sensor 46 that detects the temperature of indoor air flowing into the unit (that is, the indoor temperature Tr) is provided on the indoor air inlet side of the indoor unit 4. In this embodiment, the liquid side temperature sensor 44, the gas side temperature sensor 45, and the room temperature sensor 46 are thermistors. In addition, the indoor unit 4 includes an indoor-side control unit 47 that controls the operation of each unit constituting the indoor unit 4. And the indoor side control part 47 has the microcomputer, memory, etc. which were provided in order to control the indoor unit 4, and is with the remote control (not shown) for operating the indoor unit 4 separately. Control signals and the like can be exchanged between them, and control signals and the like can be exchanged with the outdoor unit 2.

<Outdoor unit>
The outdoor unit 2 is installed on a rooftop of a building or the like, and is connected to the indoor units 4 and 5 via the liquid refrigerant communication pipe 6 and the gas refrigerant communication pipe 7. The circuit 10 is configured.
Next, the configuration of the outdoor unit 2 will be described. The outdoor unit 2 mainly includes an outdoor refrigerant circuit 10 c that constitutes a part of the refrigerant circuit 10. The outdoor refrigerant circuit 10c 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, a liquid side closing valve 25, and a gas side closing. And a valve 26.

The compressor 21 is a compressor whose operating capacity can be varied. In the present embodiment, the compressor 21 is a positive displacement compressor driven by a motor 21a controlled by an inverter. In the present embodiment, the number of the compressors 21 is only one. However, the present invention is not limited to this, and two or more compressors may be connected in parallel according to the number of indoor units connected. Good.
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 condenser for the refrigerant compressed in the compressor 21, and the indoor heat exchanger 42 is used. , 52 is connected to the discharge side of the compressor 21 and the gas side of the outdoor heat exchanger 23 in order to function as an evaporator of refrigerant condensed in the outdoor heat exchanger 23 (specifically Specifically, 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), and the indoor heat exchangers 42 and 52 are compressed by the compressor 21 during heating operation. In order for the outdoor heat exchanger 23 to function as a refrigerant evaporator to be condensed in the indoor heat exchangers 42 and 52, the discharge side of the compressor 21 and the gas refrigerant communication pipe 7 side And connect It is possible to connect the gas side of the suction side and the outdoor heat exchanger 23 of Rutotomoni compressor 21 (see dashed four-way switching valve 22 in FIG. 1).

  In the present embodiment, 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. It is a heat exchanger that functions as a refrigerant evaporator during heating operation. 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.

  In the present embodiment, the outdoor unit 2 includes an outdoor fan 27 for sucking outdoor air into the unit, supplying the outdoor air to the outdoor heat exchanger 23, and then discharging the outdoor heat exchanger 23 to the outside. It is possible to exchange heat with the refrigerant flowing through the vessel 23. The outdoor fan 27 is a fan capable of changing the flow rate of air supplied to the outdoor heat exchanger 23. In the present embodiment, the outdoor fan 27 is a propeller fan driven by a motor 27a including a DC fan motor.

The accumulator 24 is connected between the four-way switching valve 22 and the compressor 21 and is a container capable of storing surplus refrigerant generated in the refrigerant circuit 10 in accordance with the operation load of the indoor units 4 and 5. is there.
The liquid side shutoff valve 25 and the gas side shutoff valve 26 are valves provided at connection ports with external devices and pipes (specifically, the liquid refrigerant communication pipe 6 and the gas refrigerant communication pipe 7). 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.

  The outdoor unit 2 is provided with various sensors. Specifically, the outdoor unit 2 includes a suction pressure sensor 28 that detects the suction pressure Ps of the compressor 21, a discharge pressure sensor 29 that detects the discharge pressure Pd of the compressor 21, and a suction temperature Ts of the compressor 21. An intake temperature sensor 32 for detecting the discharge temperature and a discharge temperature sensor 33 for detecting the discharge temperature Td of the compressor 21 are provided. The suction temperature sensor 32 is provided on the inlet side of the accumulator 24. The outdoor heat exchanger 23 has a heat exchange temperature sensor that detects the temperature of the refrigerant flowing in the outdoor heat exchanger 23 (that is, the refrigerant temperature corresponding to the condensation temperature Tc during the cooling operation or the evaporation temperature Te during the heating operation). 30 is provided. On the liquid side of the outdoor heat exchanger 23, a liquid side temperature sensor 31 that detects the temperature of the refrigerant in the liquid state or the gas-liquid two-phase state is provided. An outdoor air temperature sensor 34 that detects the temperature of the outdoor air flowing into the unit (that is, the outdoor air temperature Ta) is provided on the outdoor air inlet side of the outdoor unit 2. In addition, the outdoor unit 2 includes an outdoor side control unit 35 that controls the operation of each unit constituting the outdoor unit 2. The outdoor control unit 35 includes a microcomputer provided for controlling the outdoor unit 2, an inverter circuit for controlling the memory and the motor 21 a, and the like, and the indoor side control units of the indoor units 4 and 5. Control signals and the like can be exchanged with 47 and 57. That is, the indoor side control units 47 and 57 and the outdoor side control unit 35 constitute a control unit 8 that controls the operation of the entire air conditioner 1. As shown in FIG. 2, the control unit 8 is connected so that it can receive detection signals of various sensors 29 to 34, 44 to 46, and 54 to 56, and various types based on these detection signals and the like. It connects so that apparatus and valve 21,22,27a, 41,43a, 51,53a can be controlled. The control unit 8 is connected to a warning display unit 9 including an LED or the like for notifying that a refrigerant leak has been detected in the refrigerant leak detection mode described later. Here, FIG. 2 is a control block diagram of the air conditioner 1.

  As described above, the refrigerant circuit 10 of the air conditioner 1 is configured by connecting the indoor refrigerant circuits 10a and 10b, the outdoor refrigerant circuit 10c, and the refrigerant communication pipes 6 and 7. The air conditioner 1 of the present embodiment is operated by switching the cooling operation and the heating operation by the four-way switching valve 22 by the control unit 8 including the indoor side control units 47 and 57 and the outdoor side control unit 35. In addition, the devices of the outdoor unit 2 and the indoor units 4 and 5 are controlled according to the operation load of the indoor units 4 and 5.

(2) Operation | movement of an air conditioning apparatus Next, operation | movement of the air conditioning apparatus 1 of this embodiment is demonstrated.
As an operation mode of the air conditioner 1 of the present embodiment, a normal operation mode for controlling each device of the outdoor unit 2 and the indoor units 4 and 5 according to the operation load of the indoor units 4 and 5, and an air conditioner And a refrigerant at the outlet of the outdoor heat exchanger 23 that functions as a condenser while cooling the indoor units 4 and 5 after the test operation is finished and the normal operation is started. There is a refrigerant leakage detection mode in which the degree of supercooling is detected to determine whether or not the amount of refrigerant charged in the refrigerant circuit 10 is appropriate. The normal operation mode mainly includes a cooling operation and a heating operation. Further, the test operation mode includes an automatic refrigerant charging operation and a control variable changing operation.

Hereinafter, the operation | movement in each operation mode of the air conditioning apparatus 1 is demonstrated.
<Normal operation mode>
First, the cooling operation in the normal operation mode will be described with reference to FIGS. 1 and 2.
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 connected to the gas side of the exchanger 52. Further, the liquid side closing valve 25 and the gas side closing valve 26 are opened, and the opening degrees of the indoor expansion valves 41 and 51 are adjusted so that the degree of superheat of the refrigerant at the outlets of the indoor heat exchangers 42 and 52 becomes a predetermined value. It has become so. In the present embodiment, the degree of superheat of the refrigerant at the outlets of the indoor heat exchangers 42 and 52 is the refrigerant temperature value detected by the liquid side temperature sensors 44 and 54 from the refrigerant temperature value detected by the gas side temperature sensors 45 and 55. Or the suction pressure Ps of the compressor 21 detected by the suction pressure sensor 28 is converted into a saturation temperature value corresponding to the evaporation temperature Te and detected by the gas side temperature sensors 45 and 55. This is detected by subtracting the saturation temperature value of the refrigerant from the refrigerant temperature value. Although not employed in the present embodiment, the refrigerant temperature value corresponding to the evaporation temperature Te detected by the liquid side temperature sensors 44, 54 is subtracted from the refrigerant temperature value detected by the gas side temperature sensors 45, 55. Is provided with a temperature sensor for detecting the degree of superheat of the refrigerant at the outlets of the indoor heat exchangers 42 and 52, or detecting the temperature of the refrigerant flowing in the indoor heat exchangers 42 and 52, and the evaporation detected by this temperature sensor. The degree of superheat of the refrigerant at the outlets of the indoor heat exchangers 42 and 52 may be detected by subtracting the refrigerant temperature value corresponding to the temperature Te from the refrigerant temperature value detected by the gas side temperature sensors 45 and 55. .

  When the compressor 21, the outdoor fan 27, and the indoor fans 43, 53 are started in the state of the refrigerant circuit 10, 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 sent to the indoor units 4 and 5 via the liquid-side closing valve 25 and the liquid refrigerant communication pipe 6.
The high-pressure liquid refrigerant sent to the indoor units 4 and 5 is reduced in pressure by the indoor expansion valves 41 and 51 to become a low-pressure gas-liquid two-phase refrigerant and sent to the indoor heat exchangers 42 and 52, and the indoor heat The exchangers 42 and 52 exchange heat with room air and are evaporated to become a low-pressure gas refrigerant. Here, the indoor expansion valves 41 and 51 control the flow rate of the refrigerant flowing in the indoor heat exchangers 42 and 52 so that the degree of superheat at the outlets of the indoor heat exchangers 42 and 52 becomes a predetermined value. The low-pressure gas refrigerant evaporated in the indoor heat exchangers 42 and 52 has a predetermined degree of superheat. Thus, the refrigerant | coolant of the flow volume according to the driving | running load requested | required in the air-conditioning space in which each indoor unit 4 and 5 was installed flows through each indoor heat exchanger 42 and 52.

  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. Here, depending on the operating load of the indoor units 4 and 5, for example, when the operating load of one of the indoor units 4 and 5 is small or stopped, or the operating loads of both the indoor units 4 and 5 are When excess refrigerant is generated in the refrigerant circuit 10 as in the case where the refrigerant is small, the excess refrigerant accumulates in the accumulator 24.

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 shown 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 52, and the suction side of the compressor 21 is the outdoor heat. It is connected to the gas side of the exchanger 23. Further, the liquid side shutoff valve 25 and the gas side shutoff valve 26 are opened, and the opening degrees of the indoor expansion valves 41 and 51 are adjusted so that the refrigerant subcooling degree at the outlets of the indoor heat exchangers 42 and 52 becomes a predetermined value. It has come to be. In the present embodiment, the degree of refrigerant supercooling at the outlets of the indoor heat exchangers 42 and 52 is calculated by converting the discharge pressure Pd of the compressor 21 detected by the discharge pressure sensor 29 into a saturation temperature value with respect to the condensation temperature Tc. It is detected by subtracting the saturation temperature value of the refrigerant from the refrigerant temperature value detected by the liquid side temperature sensors 44 and 54 from the saturation temperature value of the refrigerant. Although not adopted in this embodiment, a temperature sensor for detecting the temperature of the refrigerant flowing in the indoor heat exchangers 42 and 52 is provided, and the refrigerant temperature value corresponding to the condensation temperature Tc detected by this temperature sensor. May be subtracted from the refrigerant temperature value detected by the liquid-side temperature sensors 44 and 54 to detect the degree of supercooling of the refrigerant at the outlets of the indoor heat exchangers 42 and 52.

When the compressor 21, the outdoor fan 27, and the indoor fans 43 and 53 are started in the state of the refrigerant circuit 10, 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 is performed. It is sent to the indoor units 4 and 5 via the valve 22, the gas side closing valve 26 and the gas refrigerant communication pipe 7.
The high-pressure gas refrigerant sent to the indoor units 4 and 5 is subjected to heat exchange with the indoor air in the outdoor heat exchangers 42 and 52 to be condensed into a high-pressure liquid refrigerant, and then the indoor expansion valve 41. , 51 is reduced to a low-pressure gas-liquid two-phase refrigerant. Here, the indoor expansion valves 41 and 51 control the flow rate of the refrigerant flowing in the indoor heat exchangers 42 and 52 so that the degree of supercooling at the outlets of the indoor heat exchangers 42 and 52 becomes a predetermined value. The high-pressure liquid refrigerant condensed in the indoor heat exchangers 42 and 52 has a predetermined degree of supercooling. Thus, the refrigerant | coolant of the flow volume according to the driving | running load requested | required in the air-conditioning space in which each indoor unit 4 and 5 was installed flows through each indoor heat exchanger 42 and 52.

  This low-pressure gas-liquid two-phase refrigerant is sent to the outdoor unit 2 via the liquid refrigerant communication pipe 6 and flows into the outdoor heat exchanger 23 via the liquid-side closing valve 25. The low-pressure gas-liquid two-phase refrigerant flowing into the outdoor heat exchanger 23 is condensed by exchanging heat with the outdoor air supplied by the outdoor fan 27 to become 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. Here, depending on the operating load of the indoor units 4 and 5, for example, when the operating load of one of the indoor units 4 and 5 is small or stopped, or the operating loads of both the indoor units 4 and 5 are When a surplus refrigerant amount is generated in the refrigerant circuit 10 as in the case where the refrigerant is small, the surplus refrigerant is accumulated in the accumulator 24 as in the cooling operation.

Thus, the normal operation process including the cooling operation and the heating operation is performed by the control unit 8 functioning as a normal operation control unit that performs the normal operation including the cooling operation and the heating operation.
<Trial run mode>
Next, the trial operation mode will be described with reference to FIGS. Here, FIG. 3 is a flowchart of the test operation mode. In the present embodiment, in the test operation mode, first, the automatic refrigerant charging operation in step S1 is performed, and then the control variable changing operation in step S2 is performed.

In the present embodiment, an outdoor unit 2 preliminarily filled with a predetermined amount of refrigerant and indoor units 4 and 5 are installed and connected via a liquid refrigerant communication pipe 6 and a gas refrigerant communication pipe 7 at the site. An example will be described in which after the circuit 10 is configured, the refrigerant circuit 10 is additionally filled with a refrigerant that is insufficient according to the lengths of the liquid refrigerant communication pipe 6 and the gas refrigerant communication pipe 7.
<Step S1: Automatic refrigerant charging operation>
First, the liquid side closing valve 25 and the gas side closing valve 26 of the outdoor unit 2 are opened, and the refrigerant circuit 10 is filled with the refrigerant filled in the outdoor unit 2 in advance.

Next, when a person who performs a trial run issues a command to start a trial run directly to the control unit 8 or remotely through a remote controller (not shown) or the like, the control unit 8 shows that in FIG. Steps S11 to S13 are performed. Here, FIG. 4 is a flowchart of the automatic refrigerant charging operation.
<Step S11: Refrigerant amount determination operation>
When an instruction to start the automatic refrigerant charging operation is made, the refrigerant circuit 10 is in a state where the four-way switching valve 22 of the outdoor unit 2 is shown by a solid line in FIG. 51 is opened, the compressor 21, the outdoor fan 27, and the indoor fans 43, 53 are activated, and all the indoor units 4, 5 are forcibly cooled (hereinafter referred to as total indoor unit operation). Done.

  Then, in the refrigerant circuit 10, the high-pressure gas refrigerant compressed and discharged in the compressor 21 flows through the flow path from the compressor 21 to the outdoor heat exchanger 23 that functions as a condenser, and the outdoor heat that functions as a condenser. A high-pressure refrigerant that changes phase from a gas state to a liquid state by heat exchange with outdoor air flows in the exchanger 23, and includes a liquid refrigerant communication pipe 6 from the outdoor heat exchanger 23 to the indoor expansion valves 41 and 51. A high-pressure liquid refrigerant flows through the passage, and a low-pressure refrigerant that changes in phase from a gas-liquid two-phase state to a gas state due to heat exchange with indoor air flows in the indoor heat exchangers 42 and 52 functioning as an evaporator, A low-pressure gas refrigerant flows through the flow path including the gas refrigerant communication pipe 7 and the accumulator 24 from the indoor heat exchangers 42 and 52 to the compressor 21.

Next, the following device control is performed to shift to an operation for stabilizing the state of the refrigerant circulating in the refrigerant circuit 10. Specifically, the rotational speed f of the motor 21a of the compressor 21 is controlled to be constant at a predetermined value (constant compressor rotational speed control), and the indoor heat exchangers 42 and 52 functioning as an evaporator are overheated. The indoor expansion valves 41 and 51 are controlled so that the degree SH _i is constant at a predetermined value (hereinafter referred to as indoor heat exchange superheat degree constant control). Here, the constant rotation speed control is performed in order to stabilize the flow rate of the refrigerant sucked and discharged by the compressor 21. The superheat control is performed in order to make the amount of refrigerant in the indoor heat exchangers 42 and 52 and the gas refrigerant communication pipe 7 constant.

  Then, in the refrigerant circuit 10, the state of the refrigerant circulating in the refrigerant circuit 10 becomes stable, and the amount of refrigerant in the equipment and piping other than the outdoor heat exchanger 23 becomes substantially constant. Thus, when the refrigerant circuit 10 starts to be filled with the refrigerant, it is possible to create a state in which only the amount of liquid refrigerant accumulated in the outdoor heat exchanger 23 changes (hereinafter, this operation is referred to as a refrigerant amount determination operation).

In this way, the control unit 8 that functions as the refrigerant amount determination operation control unit that performs the refrigerant amount determination operation including the indoor unit total number operation, the compressor rotational speed constant control, and the indoor heat exchange superheat degree constant control is performed by step S11. Is performed.
Unlike the present embodiment, when the outdoor unit 2 is not prefilled with the refrigerant, the refrigerant is charged until the refrigerant amount reaches a level at which the refrigeration cycle operation can be performed prior to the processing of step S11. There is a need to do.

<Step S12: Accumulation of operation data when refrigerant is charged>
Next, while performing the refrigerant quantity determination operation, the refrigerant circuit 10 is additionally charged with the refrigerant. At this time, in step S12, the refrigerant or the component device that flows in the refrigerant circuit 10 when the refrigerant is additionally charged. Are acquired as operation data and stored in the memory of the control unit 8. In the present embodiment, the degree of supercooling SC _{o at} the outlet of the outdoor heat exchanger 23, the outside air temperature Ta, the room temperature Tr, the discharge pressure Pd, and the suction pressure Ps are controlled as operation data during refrigerant charging. Stored in the memory of the unit 8. In this embodiment, the degree of refrigerant supercooling SC _{o at} the outlet of the outdoor heat exchanger 23 is detected by the liquid side temperature sensor 31 from the refrigerant temperature value detected by the heat exchanger temperature sensor 30 corresponding to the condensation temperature Tc. The refrigerant is detected by subtracting the refrigerant temperature value, or the discharge pressure Pd of the compressor 21 detected by the discharge pressure sensor 29 is converted into a saturation temperature value corresponding to the condensation temperature Tc, and the saturation temperature of this refrigerant It is detected by subtracting the refrigerant temperature value detected by the liquid side temperature sensor 31 from the value.

This step S12 is repeated until a condition for determining whether or not the refrigerant amount is appropriate in step S13, which will be described later, so that the above-described operation state quantity at the time of refrigerant charging is from the start to the completion of the additional charging of the refrigerant. Is stored in the memory of the control unit 8 as operation data when the refrigerant is charged. The operating data stored in the memory of the control unit 8, the accumulation of the operating data between to complete once initiated additional refrigerant charging, for example, the degree of supercooling SC _o for each appropriate temperature interval while, the other operation state quantity that corresponds to these degrees of subcooling SC _o as such accumulated may be accumulated properly thinned the operation data.

  As described above, the process of step S12 is performed by the control unit 8 functioning as a state quantity accumulation unit that accumulates the operation state quantity of the refrigerant flowing in the refrigerant circuit 10 or the component device during operation accompanied by refrigerant filling as operation data. The operation state amount when the refrigerant circuit 10 is filled with an amount of refrigerant smaller than the amount of refrigerant after completion of additional charging of the refrigerant (hereinafter referred to as initial refrigerant amount) can be obtained as the operation data.

<Step S13: Determination of Appropriateness of Refrigerant Amount>
As described above, when additional charging of the refrigerant into the refrigerant circuit 10 is started, the amount of refrigerant in the refrigerant circuit 10 gradually increases, so the amount of refrigerant in the outdoor heat exchanger 23 increases, and the outdoor heat exchanger 23 A tendency for the degree of supercooling SC _{o at the} outlet to increase appears. This tendency means that there is a correlation as shown in FIG. 5 between the degree of supercooling SC _{o at} the outlet of the outdoor heat exchanger 23 and the amount of refrigerant charged in the refrigerant circuit 10. Yes. Here, FIG. 5 is a graph showing the degree of supercooling SC _o at the outlet of the outdoor heat exchanger 23 in the refrigerant quantity judging operation, the relationship between the outside air temperature Ta and the refrigerant quantity Ch. This correlation indicates that the specified refrigerant in which the refrigerant is set in advance in the refrigerant circuit 10 when the above-described refrigerant amount determination operation is performed using the air conditioner 1 in a state immediately after being installed and used in the field. The figure shows the relationship between the value of the degree of supercooling SC _o at the outlet of the outdoor heat exchanger 23 (hereinafter referred to as the specified value of the degree of supercooling SC _o ) and the outside air temperature Ta when it is filled up to the amount. That is, (specifically, the refrigerant automatic filling) commissioning specified value of the supercooling degree SC _o is determined at the outlet of the outdoor heat exchanger 23 by the outside air temperature Ta of the specified value of the subcooling degree SC _o by comparing the current value of supercooling degree SC _o detected during refrigerant charging, the refrigerant quantity of appropriateness charged in the refrigerant circuit 10 is means that it can be determined by additional refrigerant charging.

Step S13 is a process of determining the suitability of the amount of refrigerant charged in the refrigerant circuit 10 by additional charging of the refrigerant using the correlation as described above.
That is, when the refrigerant amount to be additionally charged is small and the refrigerant amount in the refrigerant circuit 10 has not reached the initial refrigerant amount, the refrigerant amount in the outdoor heat exchanger 23 is small. Here, the state in which the amount of refrigerant in the outdoor heat exchanger 23 is small means that the current value of the degree of supercooling SC _o at the outlet of the outdoor heat exchanger 23 is smaller than the specified value of the degree of supercooling SC _o. . For this reason, in step S13, when the value of the degree of supercooling SC _o at the outlet of the outdoor heat exchanger 23 is smaller than the specified value and the additional charging of the refrigerant has not been completed, the current value of the degree of supercooling SC _o is obtained. Until the value reaches the specified value, the process of step S13 is repeated. Further, if the current value of supercooling degree SC _o reaches the prescribed value, additional refrigerant charging is completed, the step S1 as a refrigerant quantity charging operation process is completed. In addition, there are cases where the specified refrigerant amount calculated from the pipe length, the capacity of the component equipment, etc. at the site does not match the initial refrigerant amount after completion of the additional charging of the refrigerant, but in this embodiment, additional charging of the refrigerant The value of the degree of supercooling SC _{o and} the value of other operating state quantities when the operation is completed is used as the reference value of the operating state quantity such as the degree of supercooling SC _o in the refrigerant leakage detection mode described later.

Thus, the process of step S13 is performed by the control unit 8 that functions as a refrigerant amount determination unit that determines the suitability of the refrigerant amount charged in the refrigerant circuit 10 in the refrigerant amount determination operation.
Unlike this embodiment, when the refrigerant is not additionally charged and the amount of refrigerant prefilled in the outdoor unit 2 is sufficient as the amount of refrigerant in the refrigerant circuit 10, it is substantially automatic. The refrigerant charging operation is an operation for only accumulating data of the operation state quantity in the initial refrigerant quantity.

<Step S2: Control variable change operation>
When the above-described automatic refrigerant charging operation in step S1 is completed, the process proceeds to a control variable changing operation in step S2. In the control variable changing operation, the control unit 8 performs the processes of steps S21 to S23 shown in FIG. Here, FIG. 6 is a flowchart of the control variable changing operation.

<Steps S21 to S23: Control variable change operation and operation data accumulation during this operation>
In step S21, after the above-described automatic refrigerant charging operation is finished, the refrigerant quantity determination operation similar to that in step S11 is performed in a state where the refrigerant circuit 10 is filled with the initial refrigerant quantity.
Here, in the state where the refrigerant amount determination operation is performed in the state after being filled up to the initial refrigerant amount, the air volume of the outdoor fan 27 is changed, so that during the trial operation, that is, the installation of the air conditioner 1 Later, the heat exchange performance of the indoor heat exchangers 42 and 52 is changed by performing an operation that simulates the state in which the heat exchange performance of the outdoor heat exchanger 23 is changed or by changing the air volume of the indoor fans 43 and 53. An operation that simulates the state is performed (hereinafter, such an operation is referred to as a control variable change operation).

  For example, in the refrigerant amount determination operation, if the air volume of the outdoor fan 27 is reduced, the heat transfer coefficient K of the outdoor heat exchanger 23 is reduced and the heat exchange performance is lowered. Therefore, as shown in FIG. 7, the outdoor heat exchanger The refrigerant condensing temperature Tc at 23 increases, and the discharge pressure Pd of the compressor 21 corresponding to the refrigerant condensing pressure Pc at the outdoor heat exchanger 23 tends to increase. Further, in the refrigerant amount determination operation, if the air volume of the indoor fans 43 and 53 is reduced, the heat transfer coefficient K of the indoor heat exchangers 42 and 52 is reduced and the heat exchange performance is lowered. Therefore, as shown in FIG. The evaporating temperature Te of the refrigerant in the indoor heat exchangers 42 and 52 is lowered, whereby the suction pressure Ps of the compressor 21 corresponding to the evaporating pressure Pe of the refrigerant in the indoor heat exchangers 42 and 52 tends to be lowered. When such a control variable change operation is performed, the initial refrigerant amount charged in the refrigerant circuit 10 remains constant, and the refrigerant flowing through the refrigerant circuit 10 or the operation state quantity of the component device varies according to each operation condition. Will do. Here, FIG. 7 is a graph showing the relationship between the discharge pressure Pd and the outside air temperature Ta in the refrigerant amount determination operation. FIG. 8 is a graph showing the relationship between the suction pressure Ps and the outside air temperature Ta in the refrigerant quantity determination operation.

In step S <b> 22, the operation state quantity of the refrigerant or the component device that flows in the refrigerant circuit 10 under each operation condition of the control variable change operation is acquired as operation data and stored in the memory of the control unit 8. In the present embodiment, the degree of supercooling SC _{o at} the outlet of the outdoor heat exchanger 23, the outside air temperature Ta, the room temperature Tr, the discharge pressure Pd, and the suction pressure Ps are the operation data at the start of refrigerant charging. It is stored in the memory of the control unit 8.

This step S22 is repeated until it is determined in step S23 that all the operating conditions of the control variable changing operation have been executed.
In this way, the state in which the heat exchange performance of the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52 is changed by simulating the air volume of the outdoor fan 27 and the indoor fans 43 and 53 while performing the refrigerant amount determination operation is simulated. Steps S21 and S23 are performed by the control unit 8 functioning as a control variable change operation unit that performs a control variable change operation including the operation to be performed. In addition, since the process of step S22 is performed by the control unit 8 functioning as a state quantity accumulation unit that accumulates, as operation data, the refrigerant flowing in the refrigerant circuit 10 or the operation state quantity of the component device during the control variable change operation, the outdoor heat The amount of operation state in the case of performing an operation simulating the state in which the heat exchange performance of the exchanger 23 and the indoor heat exchangers 42 and 52 is changed can be obtained as operation data.

<Refrigerant leak detection mode>
Next, the refrigerant leakage detection mode will be described with reference to FIGS. Here, FIG. 9 is a flowchart of the refrigerant leakage detection mode.
In the present embodiment, during the cooling operation or heating operation in the normal operation mode, the refrigerant in the refrigerant circuit 10 is externally introduced due to an unexpected cause on a regular basis (for example, when it is not necessary to perform air conditioning during holidays or late at night). An example will be described in which it is detected whether there is leakage.

<Step S31: Determination of whether or not the normal operation mode has elapsed for a certain time>
First, it is determined whether or not the operation in the normal operation mode such as the cooling operation and the heating operation described above has passed for a certain period of time (every month, etc.). Control goes to step S32.
<Step S32: Refrigerant Quantity Determination Operation>
When the operation in the normal operation mode has elapsed for a certain period of time, the indoor unit total number operation, the compressor rotation speed constant control, and the indoor heat exchange superheat degree constant control are performed as in step S11 of the refrigerant automatic charging operation described above. A refrigerant quantity determination operation is performed. Here, the rotation speed f of the compressor 21 and the superheat degree SH _{i at} the outlets of the indoor heat exchangers 42 and 52 are the rotation speed f and the superheat degree SH _i in the refrigerant quantity determination operation in step S11 of the automatic refrigerant charging operation. The same value as the predetermined value is used.

In this way, the control unit 8 that functions as the refrigerant amount determination operation control unit that performs the refrigerant amount determination operation including the indoor unit total number operation, the compressor rotation speed constant control, and the indoor heat exchange superheat degree constant control, performs step S32. Is performed.
<Steps S33 to S35: Determination of appropriateness of refrigerant amount, return to normal operation, warning display>
When the refrigerant in the refrigerant circuit 10 leaks to the outside, the amount of refrigerant in the refrigerant circuit 10 decreases, so that the current value of the degree of supercooling SC _o at the outlet of the outdoor heat exchanger 23 tends to decrease (see FIG. 5). ). That is, this means that you can determine the refrigerant quantity adequacy filled in the refrigerant circuit 10 by comparing the current value of supercooling degree SC _o at the outlet of the outdoor heat exchanger 23. In the present embodiment, the current value and the initial refrigerant charged into the refrigerant circuit 10 during the automatic refrigerant charging operation completion of the above subcooling degree SC _o at the outlet of the outdoor heat exchanger 23 in the refrigerant leak detection during operation by comparing the reference value of supercooling degree SC _o corresponding to the amount, the determination of the refrigerant quantity adequacy, that is to perform refrigerant leakage detection.

Here, the reference value of the degree of supercooling SC _o corresponding to the initial amount of refrigerant charged in the refrigerant circuit 10 at the completion of the automatic refrigerant charging operation described above is used as the reference value of the degree of supercooling SC _o during the refrigerant leak detection operation. As a problem, the heat exchange performance is deteriorated due to the deterioration of the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52 over time.
In general, the heat exchange performance of a heat exchanger is determined by a multiplication value of a heat transfer coefficient K and a heat transfer area A (hereinafter referred to as coefficient KA), and this coefficient KA is multiplied by an internal / external temperature difference of the heat exchanger. Determines the amount of heat exchange. For this reason, as long as the coefficient KA is constant, the heat exchange performance of the heat exchanger is the difference between the inside and outside temperature (in the case of the outdoor heat exchanger 23, the outside air temperature Ta and the temperature of the refrigerant flowing in the outdoor heat exchanger 23). In the case of the indoor heat exchangers 42 and 52, the temperature difference between the indoor temperature Tr and the evaporation temperature Te as the refrigerant temperature flowing in the indoor heat exchangers 42 and 52). Will be.

However, the coefficient KA fluctuates due to aging deterioration such as contamination of the plate fins and heat transfer tubes of the outdoor heat exchanger 23 and clogging of the plate fins, and therefore, the coefficient KA is not a constant value in practice. . Specifically, the coefficient KA in the state in which aged deterioration has occurred is smaller than the coefficient KA in the state immediately after the outdoor heat exchanger 23 (that is, the air conditioner 1) is installed on the site and started to be used. As described above, when the coefficient KA varies, the correlation between the refrigerant pressure (that is, the condensation pressure Pc) in the outdoor heat exchanger 23 and the outside air temperature Ta is almost uniquely determined under the condition that the coefficient KA is constant ( In contrast to the reference line in FIG. 7, the correlation between the condensation pressure Pc and the outdoor air temperature Ta in the outdoor heat exchanger 23 changes according to the change in the coefficient KA (other than the reference line in FIG. 7). See the line). For example, the condensation pressure Pc in the outdoor heat exchanger 23 that has deteriorated over time under the same outdoor air temperature Ta condition is the outdoor heat exchange in a state immediately after the outdoor heat exchanger 23 is installed and started to be used. Compared with the condensation pressure Pc in the condenser 23, the condensation pressure Pc increases as the coefficient KA decreases (see FIG. 10), and the internal and external temperature difference in the outdoor heat exchanger 23 fluctuates in an increasing direction. Therefore, as the refrigerant quantity judging means, when compared with the reference value of the current value and the subcooling degree SC _o supercooling degree SC _o use determining method the appropriateness of the amount of refrigerant through the outdoor heat exchanger 23 on the current supercooling degree SC _o after aging has occurred, to the outdoor heat exchanger 23 is compared with a reference value of supercooling degree SC _o in a state immediately after use in country has started becomes, consequently, to become comparing the degree of subcooling SC _o each other were detected in the outdoor heat exchanger 23 two air conditioning apparatus 1 configured with having different coefficients KA, over due to aging In some cases, it is not possible to eliminate the influence of fluctuations in the cooling degree SC _o and to accurately determine whether or not the refrigerant amount determination is appropriate.

This also applies to the indoor heat exchangers 42 and 52. Under the same indoor temperature Tr conditions, the evaporation pressure Pe in the indoor heat exchangers 42 and 52 in a state where deterioration has occurred is the indoor heat exchangers 42 and 52. Compared with the evaporation pressure Pe in the indoor heat exchangers 42 and 52 in a state immediately after the installation is started and the use is started, the condensation pressure Pe decreases as the coefficient KA decreases (see FIG. 11). The temperature difference between the inside and outside of the exchangers 42 and 52 will fluctuate in an increasing direction. Therefore, as the refrigerant quantity judging means, when compared with the reference value of the current value and the subcooling degree SC _o supercooling degree SC _o use determining method the appropriateness of the amount of refrigerant through the indoor heat exchanger 42 , the current supercooling degree SC _o after aging occurs in 52, and a reference value of supercooling degree SC _o in a state immediately after the use the indoor heat exchangers 42 and 52 is installed in the local has started As a result, the degree of supercooling SC _o detected in the two air conditioners 1 configured using the indoor heat exchangers 42 and 52 having different coefficients KA is compared. therefore impossible eliminate the influence of the variation of the supercooling degree SC _o due to aging, may not be determined with high accuracy appropriateness determination refrigerant quantity.

Therefore, in the air conditioner 1 of the present embodiment, the coefficient KA of the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52 varies according to the degree of aging, that is, along with the variation of the coefficient KA, Paying attention to the fact that the correlation between the condensation pressure Pc and the outdoor air temperature Ta in the outdoor heat exchanger 23 and the correlation between the evaporation pressure Pe and the indoor temperature Tr in the indoor heat exchangers 42 and 52 vary, the current value or the reference value of supercooling degree SC _o, the discharge pressure Pd of the compressor 21 corresponding to the condensation pressure Pc in the outdoor heat exchanger 23, the outside air of the supercooling degree SC _o that is used in the determination of the appropriateness By correcting the temperature Ta, the suction pressure Ps of the compressor 21 corresponding to the evaporation pressure Pe in the indoor heat exchangers 42 and 52, and the room temperature Tr, the outdoor heat exchanger 23 and the room having the same coefficient KA are corrected. Heat exchange The degree of supercooling SC _o detected in the air conditioner 1 configured using the converters 42 and 52 can be compared with each other, and the influence of fluctuations in the degree of supercooling SC _o due to deterioration over time is eliminated. I am doing so.

In addition, about the outdoor heat exchanger 23, the fluctuation | variation of the heat exchange performance by the influence of weather, such as rainy weather or a strong wind, may also arise besides aged deterioration. Specifically, in the case of rain, the plate fins and heat transfer tubes of the outdoor heat exchanger 23 may be wetted by rainwater, resulting in fluctuations in heat exchange performance, that is, fluctuations in the coefficient KA. Further, in the case of strong winds, fluctuations in heat exchange performance, that is, fluctuations in coefficient KA may occur as the air volume of the outdoor fan 27 becomes weaker or stronger due to strong winds. Regarding the influence on the heat exchange performance of the outdoor heat exchanger 23 due to the influence of the weather as described above, the correlation between the condensation pressure Pc and the outdoor air temperature Ta in the outdoor heat exchanger 23 according to the variation of the coefficient KA (see FIG. 7). ), The influence of fluctuations in the degree of supercooling SC _o due to deterioration over time can be eliminated. As a result, the influence of fluctuations in the degree of supercooling SC _o due to weather can also be eliminated. It can be done.

As a specific correction method, for example, the refrigerant amount Ch filled in the refrigerant circuit 10 is expressed as a function of the degree of supercooling SC _o , the discharge pressure Pd, the outside air temperature Ta, the suction pressure Ps, and the room temperature Tr. By calculating the refrigerant amount Ch from the current value of the degree of supercooling SC _o during the refrigerant leakage detection operation and the current value of the discharge pressure Pd, the outside air temperature Ta, the suction pressure Ps, and the indoor temperature Tr at this time, by comparison with the initial refrigerant quantity is a reference value of the amount of refrigerant, there is a method of compensating the effects of aging and weather supercooling degree SC _o at the outlet of the outdoor heat exchanger 23.

Here, the refrigerant amount Ch filled in the refrigerant circuit 10 is:
_{Ch = k1 × SC o + k2} × Pd + k3 × Ta + × k4 × Ps + k5 × Tr + k6
Therefore, the operation data accumulated in the memory of the control unit 8 (that is, the outlet of the outdoor heat exchanger 23) when the refrigerant is charged and the control variable is changed in the test operation mode described above. By performing multiple regression analysis using the degree of supercooling SC _o , outside air temperature Ta, room temperature Tr, discharge pressure Pd, and suction pressure Ps), the parameters k1 to k6 are calculated. A function of the refrigerant amount Ch can be determined.

In the present embodiment, the function of the refrigerant amount Ch is determined after the control variable change operation in the trial operation mode and before switching to the first refrigerant amount leakage detection mode. It is executed in part 8.
As described above, the function for compensating for the influence of the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52 on the degree of supercooling SC _o due to aging and weather in the detection of the presence or absence of the refrigerant leak in the refrigerant leak detection mode. Processing for determining a correction formula is performed by the control unit 8 functioning as a state quantity correction formula calculation means.

Then, the current value of the refrigerant amount Ch is calculated from the current value of the degree of supercooling SC _o at the outlet of the outdoor heat exchanger 23 during the refrigerant leak detection operation, and the reference of the refrigerant amount Ch in the reference value of the degree of supercooling SC _o is calculated. When the value is substantially the same as the value (that is, the initial refrigerant amount) (for example, the absolute value of the difference between the refrigerant amount Ch corresponding to the current value of the degree of supercooling SC _o and the initial refrigerant amount is less than a predetermined value) It is determined that there is no refrigerant leakage, and the process proceeds to the next step S34 to return to the normal operation mode.

On the other hand, the current value of the refrigerant quantity Ch is calculated from the current value of the degree of supercooling SC _o at the outlet of the outdoor heat exchanger 23 during the refrigerant leak detection operation, and a value smaller than the initial refrigerant quantity (for example, the degree of supercooling SC _If the absolute value of the difference between the refrigerant amount Ch corresponding to the current value of _o and the initial refrigerant amount is greater than or equal to a predetermined value), it is determined that refrigerant leakage has occurred, and the process of step S35 is performed. After shifting to display a warning informing that the refrigerant leakage has been detected on the warning display unit 9, the process proceeds to step S34 to return to the normal operation mode.

Thus, substantially the same conditions as to compare the degree of subcooling SC _o each other is detected in the air conditioner 1 configured by using the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52 have the same coefficient KA respectively in, it is possible to achieve the same results as the comparison between the reference value of the current value and the subcooling degree SC _o supercooling degree SC _o, to eliminate the influence of the variation of the supercooling degree SC _o by aging be able to.

In this way, the refrigerant leakage that is one of the refrigerant amount determination means that detects the presence or absence of the refrigerant leakage by determining the suitability of the refrigerant amount charged in the refrigerant circuit 10 while performing the refrigerant amount determination operation in the refrigerant leakage detection mode. The processing of steps S33 to S35 is performed by the control unit 8 that functions as a detection unit. Further, state quantity correction means for compensating for the influence on the degree of supercooling SC _o due to the aging of the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52 when detecting the presence or absence of refrigerant leakage in the refrigerant leakage detection mode. A part of the processing in step S33 is performed by the control unit 8 functioning as:

As described above, in the air conditioning apparatus 1 of the present embodiment, the control unit 8 includes the refrigerant amount determination operation unit, the state amount accumulation unit, the refrigerant amount determination unit, the control variable change operation unit, the state amount correction formula calculation unit, and By functioning as state quantity correction means, a refrigerant quantity determination system for determining the suitability of the refrigerant quantity charged in the refrigerant circuit 10 is configured.
(3) Features of the air conditioner The air conditioner 1 of the present embodiment has the following features.

(A)
In the air conditioner 1 of the present embodiment, the degree of aging from the state immediately after the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52 (that is, the air conditioner 1) are installed and used in the field. Accordingly, the coefficient KA of the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52 fluctuates, that is, with the fluctuation of the coefficient KA, the condensation pressure Pc, which is the refrigerant pressure in the outdoor heat exchanger 23, and the outside air temperature. Paying attention to the correlation between Ta and the correlation between the evaporation pressure Pe, which is the refrigerant pressure in the indoor heat exchangers 42 and 52, and the room temperature Tr (see FIGS. 10 and 11), the amount of refrigerant in the control unit 8 that functions as a determination unit and the state quantity correcting means, the current value supercooling degree SC _o of the refrigerant quantity Ch, the discharge pressure Pd, the outside air temperature Ta, the suction pressure Ps, and, expressed as a function of the room temperature Tr The current value of supercooling degree SC _o at the time of refrigerant leak detection operation and the discharge pressure Pd in this, the outside air temperature Ta, the suction pressure Ps, and, by calculating the current value of the refrigerant quantity Ch from the current value of the room temperature Tr , is compared with the initial refrigerant quantity is a reference value of the refrigerant quantity, it is possible to eliminate the influence of the variation of the supercooling degree SC _o as the operation state quantity due to aging.

Thereby, in this air conditioning apparatus 1, even if the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52 are deteriorated over time, the suitability of the amount of refrigerant charged in the apparatus, that is, the presence or absence of refrigerant leakage is determined. It can be determined with high accuracy.
In addition, regarding the outdoor heat exchanger 23, as a case where the coefficient KA fluctuates, it may be caused by weather fluctuations such as rainy weather and strong winds. , The correlation between the condensation pressure Pc, which is the refrigerant pressure in the outdoor heat exchanger 23, and the outside air temperature Ta changes. As a result, the change in the degree of supercooling SC _o at this time is changed. The influence can also be eliminated.

(B)
In the air conditioner 1 of the present embodiment, in the test operation after the air conditioner 1 is installed, the operating state quantity (specifically, the degree of supercooling _SCo , The discharge pressure Pd, the outside air temperature Ta, the suction pressure Ps, and the indoor temperature Tr reference values) are stored in the control unit 8 functioning as state quantity storage means, and the operation state quantity is used as a reference value in the refrigerant leakage detection mode. Compared with the current value of the operating state quantity, the suitability of the refrigerant quantity, that is, the presence or absence of refrigerant leakage is determined, so the initial refrigerant quantity that is actually filled in the device and the refrigerant leakage detection time The current refrigerant amount can be compared.

As a result, in the air conditioner 1, there is a variation between the prescribed refrigerant amount set in advance before the refrigerant filling and the initial refrigerant amount filled in the field, or the pipe lengths of the refrigerant communication pipes 6 and 7. , the amount of the operating state used to determine the adequacy of the refrigerant quantity I by the installation height difference between the combination and the units 2, 4, 5 of a plurality of utilization units 4 and 5 (specifically, the degree of subcooling SC _o) Even when the fluctuation reference value fluctuates, it is possible to accurately determine whether or not the amount of refrigerant charged in the apparatus is appropriate.

(C)
In the air conditioner 1 of the present embodiment, the operation state amount after being charged up to the initial refrigerant amount (specifically, the degree of supercooling SC _o , the discharge pressure Pd, the outside air temperature Ta, the suction pressure Ps, and the room temperature) (Traffic reference value) In addition to changing the control variables of the components of the air-conditioning apparatus 1 such as the outdoor fan 27 and the indoor fans 43 and 53, an operation that simulates operating conditions different from those during the trial operation The operation state quantity during operation can be stored in the control unit 8 functioning as a state quantity storage means.

  Thereby, in this air conditioning apparatus 1, the outdoor heat exchanger 23 and the indoor heat exchange are based on the data of the operating state quantity during operation in which the control variables of the component devices such as the outdoor fan 27 and the indoor fans 43 and 53 are changed. Correlation and correction formulas for various operation state quantities when the operating conditions are different as in the case where the devices 42 and 52 have deteriorated over time, and using such correlation and correction formula, It is possible to compensate for a difference in operating conditions when comparing the reference value of the state quantity and the current value of the operating state quantity. As described above, in the air conditioner 1, the reference value of the operation state quantity during the trial operation is compared with the current value of the operation state quantity based on the data of the operation state quantity during the operation in which the control variable of the component device is changed. Since it becomes possible to compensate for the difference in operating conditions during the operation, it is possible to further improve the accuracy of determining the appropriateness of the refrigerant amount charged in the apparatus.

(4) Modification 1
In the air conditioning apparatus 1 of the above, in the determination of the adequacy of the refrigerant quantity in Step S33 of the refrigerant leak detection mode, in effect, the reference value of supercooling degree SC _o after it has been filled up to the initial refrigerant quantity, supercooling The presence or absence of refrigerant leakage is detected by comparing the current value of the degree SC _o , and in addition, in step S12 of the automatic refrigerant charging operation, from the start of additional charging of the refrigerant to completion The amount of refrigerant filled in the apparatus is determined using the data of the operation state quantity in a state where the refrigerant quantity smaller than the initial refrigerant quantity is filled in the refrigerant circuit 10. May be.

For example, in step S33 of the refrigerant leakage detection mode, along with determining whether or not the refrigerant amount is appropriate by comparing the reference value of the degree of supercooling SC _o after being charged to the initial refrigerant amount and the current value of the degree of supercooling SC _o. The operation state amount data in a state in which the refrigerant amount less than the initial refrigerant amount stored in the memory of the control unit 8 is filled in the refrigerant circuit 10 is used as a reference value and compared with the current value of the operation state amount. Accordingly, it is possible to further improve the accuracy of determining whether or not the amount of refrigerant charged in the apparatus is appropriate.

(5) Modification 2
In the air conditioner 1 described above, the discharge pressure Pd, the outside air temperature Ta, the suction pressure Ps, and the room temperature Tr are used to compensate for the aging of both the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52. These four operating state quantities are used, but only the discharge pressure Pd and the outside air temperature Ta need to be considered when compensating for the aging degradation of the outdoor heat exchanger 23 alone. In addition, when compensating for aging degradation of only the indoor heat exchangers 42 and 52, only the suction pressure Ps and the indoor temperature Tr need be considered.

In this case, the control unit 8 functioning as the state quantity storage means is provided with the discharge pressure Pd and the outside air temperature Ta or the indoor heat exchanger 42 when compensating for the aging deterioration of the outdoor heat exchanger 23 alone. , 52, the data on the suction pressure Ps and the room temperature Tr are accumulated.
(6) Modification 3
In the above-described air conditioner 1, the discharge pressure Pd of the compressor 21 is set as an operating state quantity corresponding to the condensation pressure Pc as the refrigerant pressure in the outdoor heat exchanger 23, and the suction pressure Ps of the compressor 21 is set to the indoor heat. The operating state quantity corresponding to the evaporation pressure Pe as the refrigerant pressure in the exchangers 42 and 52 is accumulated in the control unit 8 functioning as a state quantity accumulating means, and the aging of the outdoor heat exchanger 23 and the indoor heat exchangers 42 and 52 is achieved. Although it was used to determine the parameters of the correction equation that compensates for deterioration or the like, the condensation temperature Tc is used instead of the discharge pressure Pd of the compressor 21, or the evaporation temperature Te is used instead of the suction pressure Ps of the compressor 21. May be used. Even in this case, as with the air conditioning apparatus 1 described above, it is possible to compensate for aging degradation and the like.

(7) Modification 4
In the air conditioner 1 described above, the outlet of the outdoor heat exchanger 23 when performing the refrigerant quantity determination operation including the indoor unit total number operation, the compressor rotational speed constant control, and the indoor heat exchange superheat degree constant control. Using the correlation (see FIG. 5) between the degree of supercooling SC _o and the amount of refrigerant charged in the refrigerant circuit 10, determination of the appropriateness of the refrigerant amount at the time of automatic refrigerant charging and at the time of refrigerant leakage detection However, using the correlation between the amount of other operating states and the amount of refrigerant charged in the refrigerant circuit 10, determination of the suitability of the amount of refrigerant at the time of automatic refrigerant charging and refrigerant leakage detection May be performed.

For example, when performing the refrigerant quantity determination operation including the indoor unit total number operation, the compressor rotation speed constant control, and the indoor heat exchange superheat degree constant control, the supercooling degree SC at the outlet of the outdoor heat exchanger 23 is performed. _{When o} becomes large, the dryness of the refrigerant flowing into the indoor heat exchangers 42 and 52 after being expanded by the indoor expansion valves 41 and 51 is lowered. Therefore, the indoor expansion valve 41 performing the indoor heat exchange superheat constant control. , 51 tends to decrease the opening. This tendency means that there is a correlation as shown in FIG. 12 between the opening degree of the indoor expansion valves 41 and 51 and the amount of refrigerant filled in the refrigerant circuit 10. Thereby, the suitability of the refrigerant quantity filled in the refrigerant circuit 10 can be determined by the opening degree of the indoor expansion valves 41 and 51.

Moreover, as a criterion for refrigerant quantity adequacy determination result by the subcooling degree SC _o at the outlet of the outdoor heat exchanger 23, and the refrigerant quantity utilizing both the judgment result by the degree of opening of the indoor expansion valves 41 and 51 The suitability of the refrigerant amount may be determined by a combination of a plurality of operating state quantities, such as determining the suitability of the refrigerant.
Note that in this case, the controller 8 that functions as the state quantity storing means, in the test operation mode, instead of supercooling degree SC _o at the outlet of the outdoor heat exchanger 23, or, together with the degree of supercooling SC _o, the indoor Data on the opening degree of the expansion valves 41 and 51 is accumulated as a reference value.

(8) Modification 5
In the air conditioner 1 described above, the refrigerant amount determination operation is an operation including all indoor unit operation, constant compressor rotation speed control, and constant indoor heat exchange superheat degree control, but the indoor heat exchange superheat degree is constant. Instead of the control, the refrigerant quantity determination operation is performed under other control conditions, and the correlation between the other operation state quantity and the refrigerant quantity filled in the refrigerant circuit 10 is used to automatically and You may determine the suitability of the refrigerant quantity at the time of refrigerant leak detection.

For example, the refrigerant amount determination operation may be performed in which the opening degree of the indoor expansion valves 41 and 51 is fixed to a predetermined value. When performing such a refrigerant quantity judging operation, since the degree of superheating SH _i at the outlets of the indoor heat exchangers 42 and 52 will vary, depending superheat degree SH _i at the outlets of the indoor heat exchangers 42 and 52 The suitability of the amount of refrigerant charged in the refrigerant circuit 10 can be determined.
In this case, the control unit 8 functioning as the state quantity accumulating means has, instead of the degree of supercooling SC _{o at} the outlet of the outdoor heat exchanger 23 and the opening degree of the indoor expansion valves 41 and 51, in the trial operation mode. Alternatively, the data of the superheat degree SH _i at the outlets of the indoor heat exchangers 42 and 52 is accumulated as a reference value.

(9) Other Embodiments Although the embodiments of the present invention have been described with reference to the drawings, the specific configuration is not limited to these embodiments and can be changed without departing from the gist of the invention. It is.
(A)
In the above-described embodiment, the example in which the present invention is applied to an air conditioner capable of switching between cooling and heating has been described. However, the present invention is not limited thereto, and the present invention is applied to an air conditioner dedicated to cooling or an air conditioner capable of simultaneous cooling and heating. You may apply.

(B)
In the above-described embodiment, the control variable change operation is performed in the test operation mode, and the parameters of the correction formula necessary for compensation for aging deterioration and the like are determined from the operation data obtained by this operation. As long as the accuracy in determination is allowed, compensation for aged deterioration or the like may be performed using a parameter of a correction equation set in advance without performing a control variable changing operation during a trial operation.

(C)
In the above-described embodiment, in the automatic refrigerant charging operation, the refrigerant circuit 10 is filled with an amount of refrigerant smaller than the initial refrigerant amount from the start to the completion of the additional refrigerant charging. Is stored in the memory of the control unit 8, but when these data are not used in the refrigerant leakage detection mode, the additional charging of the refrigerant is started and completed. It is also possible to accumulate only the operation state quantity data after being filled up to the initial refrigerant quantity without accumulating the operation state quantity data in between.

(D)
In the above-described embodiment, the control unit 8 of the air conditioner 1 performs all the functions of various operation control means, state quantity accumulation means, refrigerant quantity determination means, state quantity correction means, and state quantity correction formula calculation means. However, the present invention is not limited to this. For example, as shown in FIG. 13, the refrigerant amount determination system is permanently installed in the air conditioner 1 as a management device that manages each component device of the air conditioner 1. When the local controller 61 to be connected is connected, the air conditioner 1 and the local controller 61 may constitute a refrigerant amount determination system having various functions provided in the control unit 8 described above. For example, the local controller 61 functions as a state quantity acquisition unit that acquires the operation state quantity of the air conditioner 1, and also serves as a state quantity storage unit, a refrigerant quantity determination unit, a state quantity correction unit, and a state quantity correction formula calculation unit. A configuration such as a function is conceivable. In this case, the control unit 8 of the air conditioner 1 accumulates a large amount of operation state data used only for determining the parameters of the state quantity correction formula, or includes refrigerant quantity determination means, state quantity correction means, In addition, it is not necessary to have a function as a state quantity correction formula calculation means.

  Further, as shown in FIG. 14, a personal computer 62 is temporarily connected to the air conditioner 1 (for example, when a serviceman performs a test operation including a test operation or a refrigerant leak detection operation), and the air conditioner 1 In addition, the personal computer 62 may be configured to function in the same manner as the local controller 61 described above. Since the personal computer 62 may be used for other purposes, an external storage device is used as the state quantity storage means instead of a storage device such as a disk device built in the personal computer 62. It is desirable to do. In this case, during a test run or refrigerant leak detection operation, an external storage device is connected to the personal computer 62, and data such as operation state quantities necessary for various operations can be read or obtained in various operations. The operation of writing the data such as the operating state quantity is performed.

(E)
Further, as shown in FIG. 15, a local controller 61 is connected to the air conditioner 1 as a management device that manages each component device of the air conditioner 1 and obtains operation data. By connecting to the remote server 64 of the information management center that receives the operation data of the harmony device 1 via the network 63 and connecting the storage device 65 such as a disk device as a state quantity storage means to the remote server 64, the amount of refrigerant A determination system may be configured. For example, the local controller 61 is a state quantity acquisition unit that acquires the operating state quantity of the air conditioner 1, the storage device 65 is a state quantity storage unit, and the remote server 64 is a refrigerant quantity determination unit, a state quantity correction unit, and a state quantity correction. A configuration such as functioning as an equation calculation means is conceivable. Also in this case, the control unit 8 of the air conditioner 1 accumulates a large amount of operating state quantity data used only for determining the parameters of the state quantity correction formula, or includes refrigerant quantity determination means, state quantity correction means, and It is no longer necessary to have a function as a state quantity correction formula calculation means.

  Moreover, since a large amount of operation data from the air conditioner 1 can be stored in the storage device 65, past operation data of the air conditioner 1 including operation data in the refrigerant leakage detection mode is stored. The remote server 64 selects operation data similar to the current operation data acquired by the local controller 61 from these past operation data, and compares both data to determine the suitability of the refrigerant amount. It becomes possible to do. Thereby, it is possible to determine the suitability of the refrigerant amount in consideration of the characteristics peculiar to the air conditioner 1, and the combined use with the determination result of the suitability of the refrigerant amount by the above-described refrigerant amount judgment means can It becomes possible to determine the suitability more accurately.

  According to the present invention, in a separate type air conditioner in which an outdoor unit and an indoor unit are connected via a refrigerant communication pipe, even if the outdoor heat exchanger or the indoor heat exchanger deteriorates over time, It is possible to accurately determine whether or not the amount of refrigerant charged in the refrigerant is appropriate.

1 is a schematic refrigerant circuit diagram of an air conditioner according to an embodiment of the present invention. It is a control block diagram of an air conditioning apparatus. It is a flowchart of test run mode. It is a flowchart of a refrigerant | coolant automatic charging operation. It is a graph which shows the relationship between the subcooling degree in the exit of the outdoor heat exchanger in a refrigerant | coolant amount determination driving | operation, outside temperature, and a refrigerant | coolant amount. It is a flowchart of a control variable change operation. It is a graph which shows the relationship between the discharge pressure and external temperature in a refrigerant | coolant amount determination driving | operation. It is a graph which shows the relationship between the suction pressure and external temperature in a refrigerant | coolant amount determination driving | operation. It is a flowchart of a refrigerant | coolant leak detection mode. It is a graph which shows the relationship between the coefficient KA and a condensation pressure in an outdoor heat exchanger. It is a graph which shows the relationship between coefficient KA and an evaporation pressure in an indoor heat exchanger. It is a graph which shows the relationship between the opening degree of the indoor expansion valve in a refrigerant | coolant amount determination driving | operation, the supercooling degree and refrigerant | coolant amount in the exit of an outdoor heat exchanger. This is a refrigerant quantity determination system using a local controller. This is a refrigerant quantity determination system using a personal computer. It is a refrigerant | coolant amount determination system using a remote server and a memory | storage device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air conditioning apparatus 2 Outdoor unit 4, 5 Indoor unit 6, 7 Refrigerant communication piping 10 Refrigerant circuit 21 Compressor 23 Outdoor heat exchanger 42, 52 Indoor heat exchanger

Claims (5)

An outdoor unit (2) having a compressor (21) and an outdoor heat exchanger (23) and an indoor unit (4, 5) having an indoor heat exchanger (42, 52) are connected to a refrigerant communication pipe (6 , 7) an air conditioner comprising a refrigerant circuit (10) configured by being connected via
Refrigerant amount determination means for determining the suitability of the refrigerant amount based on the current value of the operating state quantity of the refrigerant or component equipment flowing through the refrigerant circuit and the reference value of the operating state quantity of the refrigerant or component equipment flowing through the refrigerant circuit. When,
A state amount correction unit that corrects the operation state amount using the refrigerant pressure or the refrigerant temperature in the outdoor heat exchanger and the outside air temperature when the refrigerant amount determination unit determines whether or not the refrigerant amount is appropriate;
An air conditioner (1) comprising: An outdoor unit (2) having a compressor (21) and an outdoor heat exchanger (23) and an indoor unit (4, 5) having an indoor heat exchanger (42, 52) are connected to a refrigerant communication pipe (6 , 7) an air conditioner comprising a refrigerant circuit (10) configured by being connected via
Refrigerant amount determination means for determining the suitability of the refrigerant amount based on the current value of the operating state quantity of the refrigerant or component equipment flowing through the refrigerant circuit and the reference value of the operating state quantity of the refrigerant or component equipment flowing through the refrigerant circuit. When,
A state amount correction unit that corrects the operating state amount using the refrigerant pressure or the refrigerant temperature in the indoor heat exchanger and the indoor temperature when the refrigerant amount determination unit determines whether or not the refrigerant amount is appropriate;
An air conditioner (1) comprising: An outdoor unit (2) having a compressor (21) and an outdoor heat exchanger (23), an indoor unit (4, 5) having an indoor heat exchanger (42, 52), and a refrigerant communication pipe (6, 7) an air conditioner comprising a refrigerant circuit (10) configured by being connected via
Refrigerant amount determination means for determining the suitability of the refrigerant amount based on the current value of the operating state quantity of the refrigerant or component equipment flowing through the refrigerant circuit and the reference value of the operating state quantity of the refrigerant or component equipment flowing through the refrigerant circuit. When,
When determining the suitability of the refrigerant quantity by the refrigerant quantity judging means, the operation state quantity is obtained by using the refrigerant pressure or refrigerant temperature in the outdoor heat exchanger, the outside air temperature, the refrigerant pressure or refrigerant temperature in the indoor heat exchanger, and State quantity correction means for correcting using the room temperature;
An air conditioner (1) comprising: An outdoor unit (2) having a compressor (21) and an outdoor heat exchanger (23) and an indoor unit (4, 5) having an indoor heat exchanger (42, 52) are connected to a refrigerant communication pipe (6 , 7) State quantity acquisition means for acquiring the operating state quantity of the refrigerant flowing through the refrigerant circuit or the component device from the air conditioner (1) provided with the refrigerant circuit (10) configured by being connected via When,
State quantity accumulation means for accumulating the operation state quantity acquired by the state quantity acquisition means as a reference value of the operation state quantity;
A refrigerant amount determination unit that determines whether or not the refrigerant amount is appropriate based on a current value of the operation state amount acquired by the state amount acquisition unit and a reference value of the operation state amount stored in the state amount storage unit;
When determining the suitability of the refrigerant quantity by the refrigerant quantity judging means, the operation state quantity is obtained by using the refrigerant pressure or refrigerant temperature in the outdoor heat exchanger, the outside air temperature, the refrigerant pressure or refrigerant temperature in the indoor heat exchanger, and State quantity correction means for correcting using the room temperature;
A refrigerant amount determination system for an air conditioner comprising: The state quantity acquisition means manages the air conditioner (1),
The state quantity storage means, the refrigerant quantity determination means, and the state quantity correction means are remote from the air conditioner and are connected to the state quantity acquisition means via a communication line.
The refrigerant | coolant amount determination system of the air conditioning apparatus of Claim 4.

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