# US 11,898,783 B2 · Performance degradation diagnosis system for refrigeration cycle apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,898,783 B2 - Document ID: US11898783B2 - Status: Granted - Kind: B2 - Application number: 17/598,060 - Filed: 2020-03-30 - Published: 2022-06-02 - Granted: 2024-02-13 - Earliest claimed: 2019-03-29 - Assignees: Daikin Industries, Ltd. - Applicants: Daikin Industries, Ltd. - Inventors: Shuji Fujimoto; Akihiro Inao; Shizuka Sadai; Shinichi Kasahara; Takeshi Hikawa - Web page: https://patentgrep.com/patent/US11898783B2 ## CPC - F25B 49/022: {Compressor control arrangements} - F24F 11/32: Responding to malfunctions or emergencies - F24F 11/38: Failure diagnosis - F24F 11/39: Monitoring filter performance - F25B 13/00: Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) - F25B 40/02: Subcoolers - F25B 41/24: Arrangement of shut-off valves for disconnecting a part of the refrigerant cycle, e.g. an outdoor part - F25B 41/31: Expansion valves - F25B 49/005: {of safety devices (F25B49/02 and F25B49/04 take precedence)} - F25B 49/02: for compression type machines, plants or systems - F24F 2110/10: Temperature - F24F 2110/20: Humidity - F24F 2140/20: Heat-exchange fluid temperature - F25B 2313/0293: related to the indoor fan, e.g. controlling speed - F25B 2313/0294: related to the outdoor fan, e.g. controlling speed - F25B 2313/0314: Temperature sensors near the indoor heat exchanger - F25B 2313/0315: Temperature sensors near the outdoor heat exchanger - F25B 2500/19: Calculation of parameters - F25B 2500/222: Detecting refrigerant leaks - F25B 2500/24: Low amount of refrigerant in the system - F25B 2600/025: by controlling speed - F25B 2600/0253: with variable speed - F25B 2600/11: Fan speed control - F25B 2600/111: of condenser fans - F25B 2600/112: of evaporator fans - F25B 2600/2513: Expansion valves - F25B 2700/02: Humidity - F25B 2700/04: Refrigerant level - F25B 2700/1931: Discharge pressures - F25B 2700/1933: Suction pressures - F25B 2700/2104: of an indoor room or compartment - F25B 2700/2106: of fresh outdoor air - F25B 2700/21151: at the suction side of the compressor - F25B 2700/21152: at the discharge side of the compressor - F25B 2700/2116: of a condenser - F25B 2700/21162: of the refrigerant at the inlet of the condenser - F25B 2700/21163: of the refrigerant at the outlet of the condenser - F25B 2700/2117: of an evaporator - F25B 2700/21174: of the refrigerant at the inlet of the evaporator - F25B 2700/21175: of the refrigerant at the outlet of the evaporator - Y02B 30/70: Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS - F24F: AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING (removing dirt or fumes from areas where they are produced B08B15/00; vertical ducts for carrying away waste gases from buildings E04F17/02; tops for chimneys or ventilating shafts, terminals for flues F23L17/02) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A performance degradation diagnosis system includes a determining unit, and control unit. A refrigeration cycle apparatus includes a refrigerant circuit having a compressor, heat-source-side heat exchanger, and use-side heat exchanger. The determining unit determines, based on an index indicating an operation state of the refrigeration cycle apparatus, performance degradation of the refrigeration cycle apparatus with respect to each of a plurality of performance degradation factors. In a case in which the determining unit determines performance degradation, the control unit grasps an operation condition of the refrigeration cycle apparatus which is operating. In a case in which the operation condition of the refrigeration cycle apparatus is not suitable to determine performance degradation with respect to a performance degradation factor of a determination target, the control unit controls the operation condition of the refrigeration cycle apparatus so that the operation condition of the refrigeration cycle apparatus becomes an appropriate operation condition. ## Claims ### Claim 1 A performance degradation diagnosis system for a refrigeration cycle apparatus that includes a refrigerant circuit including a compressor, a heat-source-side heat exchanger, and a use-side heat exchanger, the performance degradation diagnosis system comprising: a computer including a first determining unit configured to determine, based on an index indicating an operation state of the refrigeration cycle apparatus, performance degradation of the refrigeration cycle apparatus with respect to each of a plurality of performance degradation factors of the refrigeration cycle apparatus; and a control unit configured, before the first determining unit determines performance degradation of the refrigeration cycle apparatus with respect to each of the performance degradation factors, to obtain an operation condition of the refrigeration cycle apparatus which is operating, and in a case in which the operation condition of the refrigeration cycle apparatus is not suitable to determine performance degradation of the refrigeration cycle apparatus with respect to a performance degradation factor of a determination target, to control the operation condition of the refrigeration cycle apparatus so that the operation condition of the refrigeration cycle apparatus becomes suitable to determine performance degradation of the refrigeration cycle apparatus. ### Claim 2 (depends on 1) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 1, wherein the refrigeration cycle apparatus further includes a heat-source-side fan configured to supply air to the heat-source-side heat exchanger and an expansion valve disposed between the heat-source-side heat exchanger and the use-side heat exchanger in the refrigerant circuit to decompress refrigerant flowing in the refrigerant circuit, the performance degradation factors include a decrease in an amount of refrigerant, and in a case in which the first determining unit determines performance degradation of the refrigeration cycle apparatus due to the decrease in the amount of refrigerant, and a degree of subcooling in a refrigeration cycle of the refrigeration cycle apparatus which is operating has a value smaller than a first predetermined value, the control unit is configured to cause the refrigeration cycle apparatus to execute at least one of an operation of increasing the number of rotations of the compressor, an operation of decreasing the number of rotations of the heat-source-side fan, and an operation of decreasing an opening degree of the expansion valve, to control the operation condition of the refrigeration cycle apparatus to the operation condition suitable to determine performance degradation of the refrigeration cycle apparatus. ### Claim 3 (depends on 1) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 1, wherein the refrigeration cycle apparatus further includes a heat-source-side fan configured to supply air to the heat-source-side heat exchanger and an expansion valve disposed between the heat-source-side heat exchanger and the use-side heat exchanger in the refrigerant circuit to decompress refrigerant flowing in the refrigerant circuit, the performance degradation factors include a decrease in an amount of refrigerant, and in a case in which the first determining unit determines perforenone degradation of the refrigeration cycle apparatus due to the decrease in the amount of refrigerant, and a degree of subcooling in a refrigeration cycle of the refrigeration cycle apparatus which is operating has a value greater than a second predetermined value, the control unit is configured to cause the refrigeration cycle apparatus to execute at least one of an operation of decreasing the number of rotations of the compressor, an operation of increasing the number of rotations of the heat-source-side fan, and an operation of increasing an increase of the expansion valve, to control the operation condition of the refrigeration cycle apparatus to the operation condition suitable to determine performance degradation of the refrigeration cycle apparatus. ### Claim 4 (depends on 1) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 1, wherein the refrigeration cycle apparatus further includes a heat-source-side fan configured to supply air to the heat-source-side heat exchanger, the performance degradation factors include soiling of the heat-source-side heat exchanger, and in a case in which the first determining unit determines performance degradation of the refrigeration cycle apparatus due to the soiling of the heat-source-side heat exchanger, the control unit is configured to cause the refrigeration cycle apparatus to execute at least one of an operation of increasing the number of rotations of the compressor, and an operation of decreasing the number of rotations of the heat-source-side fan, to control the operation condition of the refrigeration cycle apparatus, which is operating, to the operation condition suitable to determine performance degradation of the refrigeration cycle apparatus. ### Claim 5 (depends on 1) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 1, wherein the refrigeration cycle apparatus further includes a use-side fan configured to supply air to the use-side heat exchanger and a filter configured to remove a foreign substance from the air to be supplied to the use-side heat exchanger, the performance degradation factors include at least one of soiling of the use-side heat exchanger and soiling of the filter, and in a case in which the first determining unit determines performance degradation of the refrigeration cycle apparatus due to at least one of the soiling of the use-side heat exchanger and the soiling of the filter, the control unit is configured to cause the refrigeration cycle apparatus to execute at least one of an operation of increasing the number of rotations of the compressor, and an operation of decreasing the number of rotations of the use-side fan, to control the operation condition of the refrigeration cycle apparatus, which is operating, to the operation condition suitable to determine performance degradation of the refrigeration cycle apparatus. ### Claim 6 (depends on 1) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 1, wherein the refrigeration cycle apparatus further includes a heat-source-side fan configured to supply air to the heat-source-side heat exchanger and an expansion valve disposed between the heat-source-side heat exchanger and the use-side heat exchanger in the refrigerant circuit to decompress refrigerant flowing in the refrigerant circuit, and in a case in which a degree of subcooling in a refrigeration cycle of the refrigeration cycle apparatus which is operating has a value smaller than or equal to a third predetermined value, the control unit is configured to cause the refrigeration cycle apparatus to execute at least one of an operation of increasing the number of rotations of the compressor, an operation of increasing the number of rotations of the heat-source-side fan, and an operation of decreasing an opening degree of the expansion valve, to control the operation condition of the refrigeration cycle apparatus to the operation condition suitable to determine performance degradation of the refrigeration cycle apparatus. ### Claim 7 (depends on 1) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 1, wherein the refrigeration cycle apparatus further includes a heat-source-side fan configured to supply air to the heat-source-side heat exchanger and an expansion valve disposed between the heat-source-side heat exchanger anti the use-side heat exchanger in the refrigerant circuit to decompress refrigerant flowing in the refrigerant circuit, and in a case in which a degree of superheating in a refrigeration cycle of the refrigeration cycle apparatus which is operating has a value smaller than or equal to a fourth predetermined value, the control unit is configured to cause the refrigeration cycle apparatus to execute at least one of an operation of increasing the number of rotations of the compressor, an operation of increasing the number of rotations of the heat-source-side fan, and an operation of decreasing an opening degree of the expansion valve, to control the operation condition of the refrigeration cycle apparatus to the operation condition suitable to determine performance degradation of the refrigeration cycle apparatus. ### Claim 8 (depends on 1) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 1, wherein the computer further includes an overall determining unit configured to determine overall performance degradation of the refrigeration cycle apparatus, in a case in which the overall determining unit determines that the refrigeration cycle apparatus has the overall performance degradation, the first determining unit being configured to determine performance degradation of the refrigeration cycle apparatus with respect to each of the plurality of performance degradation factors. ### Claim 9 (depends on 2) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 2, wherein the refrigeration cycle apparatus further includes a use-side fan configured to supply air to the use-side heat exchanger and a filter configured to remove a foreign substance from the air to be supplied to the use-side heat exchanger, the performance degradation factors include at least one of soiling of the use-side heat exchanger and soiling of the filter, and in a case in which the first determining unit determines performance degradation of the refrigeration cycle apparatus due to at least one of the soiling of the use-side heat exchanger and the soiling of the filter, the control unit is configured to cause the refrigeration cycle apparatus to execute at least one of an operation of increasing the number of rotations of the compressor, and an operation of decreasing the number of rotations of the use-side fan, to control the operation condition of the refrigeration cycle apparatus, which is operating, to the operation condition suitable to determine performance degradation of the refrigeration cycle apparatus. ### Claim 10 (depends on 2) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 2, wherein the computer further includes an overall determining unit configured to determine overall performance degradation of the refrigeration cycle apparatus, in a case in which the overall determining unit determines that the refrigeration cycle apparatus has the overall performance degradation, the first determining unit being configured to determine performance degradation of the refrigeration cycle apparatus with respect to each of the plurality of performance degradation factors. ### Claim 11 (depends on 3) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 3, wherein the refrigeration cycle apparatus further includes a use-side fan configured to supply air to the use-side heat exchanger and a filter configured to remove a foreign substance from the air to be supplied to the use-side heat exchanger, the performance degradation factors include at least one of soiling of the use-side heat exchanger and soiling of the filter, and in a case in which the first determining unit determines performance degradation of the refrigeration cycle apparatus due to at least one of the soiling of the use-side heat exchanger and the soiling of the filter, the control unit is configured to cause the refrigeration cycle apparatus to execute at least one of an operation of increasing the number of rotations of the compressor, and an operation of decreasing the number of rotations of the use-side fan, to control the operation condition of the refrigeration cycle apparatus, which is operating, to the operation condition suitable to determine performance degradation of the refrigeration cycle apparatus. ### Claim 12 (depends on 3) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 3, wherein the computer further includes an overall determining unit configured to determine overall performance degradation of the refrigeration cycle apparatus, in a case in which the overall determining unit determines that the refrigeration cycle apparatus has the overall performance degradation, the first determining unit being configured to determine performance degradation of the refrigeration cycle apparatus with respect to each of the plurality of performance degradation factors. ### Claim 13 (depends on 4) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 4, wherein the refrigeration cycle apparatus further includes a use-side fan configured to supply air to the use-side heat exchanger and a filter configured to remove a foreign substance from the air to be supplied to the use-side heat exchanger, the performance degradation factors include at least one of soiling of the use-side heat exchanger and soiling of the filter, and in a case in which the first determining unit determines performance degradation of the refrigeration cycle apparatus due to at least one of the soiling of the use-side heat exchanger and the soiling of the filter, the control unit is configured to cause the refrigeration cycle apparatus to execute at least one of an operation of increasing the number of rotations of the compressor, and an operation of decreasing the number of rotations of the use-side fan, to control the operation condition of the refrigeration cycle apparatus, which is operating, to the operation condition suitable to determine performance degradation of the refrigeration cycle apparatus. ### Claim 14 (depends on 4) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 4, wherein the computer further includes, an overall determining unit configured to determine overall performance degradation of the refrigeration cycle apparatus, in a case in which the overall determining unit determines that the refrigeration cycle apparatus has the overall performance degradation, the first determining unit being configured to determine performance degradation of the refrigeration cycle apparatus with respect to each of the plurality of performance degradation factors. ### Claim 15 (depends on 5) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 5, wherein the computer further includes an overall determining unit configured to determine overall performance degradation of the refrigeration cycle apparatus, in a case in which the overall determining unit determines that the refrigeration cycle apparatus has the overall performance degradation, the first determining unit being configured to determine performance degradation of the refrigeration cycle apparatus with respect to each of the plurality of performance degradation factors. ### Claim 16 (depends on 6) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 6, wherein the computer further includes an overall determining unit configured to determine overall performance degradation of the refrigeration cycle apparatus, in a case in which the overall determining unit determines that the refrigeration cycle apparatus has the overall performance degradation, the first determining unit being configured to determine performance degradation of the refrigeration cycle apparatus with respect to each of the plurality of performance degradation factors. ### Claim 17 (depends on 7) The performance degradation diagnosis system for a refrigeration cycle apparatus according to claim 7, wherein the computer further includes an overall determining unit configured to determine overall performance degradation of the refrigeration cycle apparatus, in a case in which the overall determining unit determines that the refrigeration cycle apparatus has the overall performance degradation, the first determining unit being configured to determine performance degradation of the refrigeration cycle apparatus with respect to each of the plurality of performance degradation factors.