# US 8,769,974 B2 · Heat pump system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,769,974 B2 - Document ID: US8769974B2 - Status: Granted - Kind: B2 - Application number: 13/202,608 - Filed: 2010-02-23 - Published: 2011-12-15 - Granted: 2014-07-08 - Earliest claimed: 2009-02-24 - Assignees: Daikin Industries, Ltd. - Applicants: Masahiro Honda - Inventors: Masahiro Honda - Web page: https://patentgrep.com/patent/US8769974B2 ## CPC - F24D 3/18: using heat pumps - F24D 3/08: in combination with systems for domestic hot-water supply - F24H 6/00: Combined water and air heaters - F25B 7/00: Compression machines, plants or systems, with cascade operation, i.e. with two or more circuits, the heat from the condenser of one circuit being absorbed by the evaporator of the next circuit (F25B9/00 takes precedence) - F25B 13/00: Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) - F24D 2200/12: Heat pump - F25B 2313/003: Indoor unit with water as a heat sink or heat source - F25B 2313/007: three pipes connecting the outdoor side to the indoor side with multiple indoor units - F25B 2313/0231: with simultaneous cooling and heating - F25B 2313/02741: using one four-way valve - F25B 2313/0294: related to the outdoor fan, e.g. controlling speed - F25B 2600/13: Pump speed control - Y02B 30/12: Hot water central heating systems using heat pumps - Y02B 30/70: Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating - F24D: DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR (using steam or condensate extracted or exhausted from steam engine plants for heating purposes F01K17/02) - F24H: FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL (steam generation F22) - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract A heat pump system includes a heat source unit, a first usage unit, and a second usage unit. The heat source unit has a heat-source-side compressor, a heat-source-side heat exchanger, a heat-source-side blower and a heat-source-side switching mechanism. The first usage unit has at least a radiation amount adjusting element and a first usage-side flow rate adjustment valve. The second usage unit has at least a second usage-side flow rate adjustment valve. In a case in which the second usage unit performs an air-cooling operation and the first usage unit performs an aqueous medium heating operation, the amount of radiation adjusted by the radiation amount adjusting element or operating capacity of the heat-source-side blower is controlled in accordance with a state of the first usage-side flow rate adjustment valve and the second usage-side flow rate adjustment valve. ## Claims ### Claim 1 A heat pump system comprising: a heat source unit having a heat-source-side compressor arranged to compress a heat-source-side refrigerant; a heat-source-side heat exchanger; a variable-capacity heat-source-side blower configured to adjust heat exchange efficiency of said heat-source-side heat exchanger; and a heat-source-side switching mechanism switchable between a heat-source-side radiating operation state in which said heat-source-side heat exchanger functions as a radiator of the heat-source-side refrigerant, and a heat-source-side evaporating operation state in which said heat-source-side heat exchanger functions as an evaporator of the heat-source-side refrigerant; a first usage unit having a first usage-side heat exchanger operable as a radiator of the heat-source-side refrigerant compressed by said heat-source-side compressor, a radiation amount adjusting element configured to adjust an amount of radiation in an aqueous medium by radiation of the heat-source-side refrigerant in said first usage-side heat exchanger, and a first usage-side flow rate adjustment valve configured to adjust a flow rate of the heat-source-side refrigerant that flows through said first usage-side heat exchanger, the first usage unit being operable to perform an aqueous medium heating operation in which the aqueous medium is heated by radiation of the heat-source-side refrigerant in said first usage-side heat exchanger; and a second usage unit having a second usage-side heat exchanger operable at least as an evaporator of the heat-source-side refrigerant in said heat-source-side radiating operation state of said heat-source-side switching mechanism, and a second usage-side flow rate adjustment valve configured to adjust a flow rate of the heat-source-side refrigerant that flows through said second usage-side heat exchanger, the second usage unit being operable to perform an air-cooling operation in which an air medium is cooled by evaporation of the heat-source-side refrigerant in said second usage-side heat exchanger, the amount of radiation adjusted by said radiation amount adjusting element or operating capacity of said heat-source-side blower being controlled in accordance with a state of said first usage-side flow rate adjustment valve and said second usage-side flow rate adjustment valve in a case in which said second usage unit performs said air-cooling operation and said first usage unit performs said aqueous medium heating operation. ### Claim 2 (depends on 1) The heat pump system according to claim 1, wherein a superheat-degree fixing control is performed in which a degree of superheat of said heat-source-side refrigerant in said second usage-side heat exchanger is fixed at a predetermined degree of superheat by adjusting an opening degree of said second usage-side flow rate adjustment valve; and a control is performed in which the airflow rate of said heat-source-side blower is decreased in a case in which said second usage-side flow rate adjustment valve reaches an opening degree equal to or greater than a predetermined opening degree. ### Claim 3 (depends on 2) The heat pump system according to claim 2, wherein said first usage-side heat exchanger is configured to exchange heat between the heat-source-side refrigerant and the aqueous medium. ### Claim 4 (depends on 3) The heat pump system according to claim 3, further comprising: an aqueous medium circuit configured to circulate an aqueous medium to exchange heat with the heat-source-side refrigerant in said first usage-side heat exchanger, said radiation amount adjusting element being a variable-capacity circulation pump, a subcooling-degree fixing control being performed in which a degree of subcooling of said heat-source-side refrigerant in said first usage-side heat exchanger is fixed at a predetermined degree of subcooling by adjusting an opening degree of said first usage-side flow rate adjustment valve, and a capacity of said circulation pump being controlled so that a flow rate of the aqueous medium circulated through said aqueous medium circuit decreases in a case in which said first usage-side flow rate adjustment valve reaches an opening degree equal to or greater than a predetermined opening degree. ### Claim 5 (depends on 2) The heat pump system according to claim 2, wherein said first usage-side heat exchanger is configured to exchange heat between the heat-source-side refrigerant and a usage-side refrigerant which is other than the heat-source-side refrigerant; and said first usage unit further includes a usage-side compressor arranged to compress the usage-side refrigerant, and a refrigerant/water heat exchanger operable as a radiator of the usage-side refrigerant to heat the aqueous medium, said first usage unit together with said first usage-side heat exchanger forming parts of a usage-side refrigerant circuit configured to circulate the usage-side refrigerant. ### Claim 6 (depends on 5) The heat pump system according to claim 5, further comprising: an aqueous medium circuit configured to circulate an aqueous medium to exchange heat with the usage-side refrigerant in said refrigerant/water heat exchanger, the aqueous medium circuit having said radiation amount adjusting element, which is a variable-capacity circulation pump, a subcooling-degree fixing control being performed in which a degree of subcooling of said heat-source-side refrigerant in said first usage-side heat exchanger is fixed at a predetermined degree of subcooling by adjusting an opening degree of said first usage-side flow rate adjustment valve, and a capacity of said circulation pump being controlled so that a flow rate of the aqueous medium circulated through said aqueous medium circuit decreases in a case in which said first usage-side flow rate adjustment valve reaches an opening degree equal to or greater than a predetermined opening degree. ### Claim 7 (depends on 2) The heat pump system according to claim 2, further comprising: a discharge refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from a discharge of said heat-source-side compressor in any of said heat-source-side radiating operation state and said heat-source-side evaporating operation state of said heat-source-side switching mechanism; a liquid refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from an outlet of said heat-source-side heat exchanger functioning as a radiator of the heat-source-side refrigerant in said heat-source-side radiating operation state of said heat-source-side switching mechanism, and introducing the heat-source-side refrigerant into an inlet of said heat-source-side heat exchanger functioning as an evaporator of the heat-source-side refrigerant from outside said heat source unit in said heat-source-side evaporating operation state of said heat-source-side switching mechanism; and a gas refrigerant communication tube capable of introducing the heat-source-side refrigerant into an intake of said heat-source-side compressor from outside said heat source unit. ### Claim 8 (depends on 1) The heat pump system according to claim 1, wherein said first usage-side heat exchanger is configured to exchange heat between the heat-source-side refrigerant and the aqueous medium. ### Claim 9 (depends on 8) The heat pump system according to claim 8, further comprising: an aqueous medium circuit configured to circulate an aqueous medium to exchange heat with the heat-source-side refrigerant in said first usage-side heat exchanger, said radiation amount adjusting element being a variable-capacity circulation pump, a subcooling-degree fixing control being performed in which a degree of subcooling of said heat-source-side refrigerant in said first usage-side heat exchanger is fixed at a predetermined degree of subcooling by adjusting an opening degree of said first usage-side flow rate adjustment valve, and a capacity of said circulation pump being controlled so that a flow rate of the aqueous medium circulated through said aqueous medium circuit decreases in a case in which said first usage-side flow rate adjustment valve reaches an opening degree equal to or greater than a predetermined opening degree. ### Claim 10 (depends on 9) The heat pump system according to claim 9, further comprising: a discharge refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from a discharge of said heat-source-side compressor in any of said heat-source-side radiating operation state and said heat-source-side evaporating operation state of said heat-source-side switching mechanism; a liquid refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from an outlet of said heat-source-side heat exchanger functioning as a radiator of the heat-source-side refrigerant in said heat-source-side radiating operation state of said heat-source-side switching mechanism, and introducing the heat-source-side refrigerant into an inlet of said heat-source-side heat exchanger functioning as an evaporator of the heat-source-side refrigerant from outside said heat source unit in said heat-source-side evaporating operation state of said heat-source-side switching mechanism; and a gas refrigerant communication tube capable of introducing the heat-source-side refrigerant into an intake of said heat-source-side compressor from outside said heat source unit. ### Claim 11 (depends on 8) The heat pump system according to claim 8, further comprising: a discharge refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from a discharge of said heat-source-side compressor in any of said heat-source-side radiating operation state and said heat-source-side evaporating operation state of said heat-source-side switching mechanism; a liquid refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from an outlet of said heat-source-side heat exchanger functioning as a radiator of the heat-source-side refrigerant in said heat-source-side radiating operation state of said heat-source-side switching mechanism, and introducing the heat-source-side refrigerant into an inlet of said heat-source-side heat exchanger functioning as an evaporator of the heat-source-side refrigerant from outside said heat source unit in said heat-source-side evaporating operation state of said heat-source-side switching mechanism; and a gas refrigerant communication tube capable of introducing the heat-source-side refrigerant into an intake of said heat-source-side compressor from outside said heat source unit. ### Claim 12 (depends on 1) The heat pump system according to claim 1, wherein said first usage-side heat exchanger is configured to exchange heat between the heat-source-side refrigerant and a usage-side refrigerant which is other than the heat-source-side refrigerant; and said first usage unit further includes a usage-side compressor arranged to compress the usage-side refrigerant, and a refrigerant/water heat exchanger operable as a radiator of the usage-side refrigerant to heat the aqueous medium, said first usage unit together with said first usage-side heat exchanger forming parts of a usage-side refrigerant circuit configured to circulate the usage-side refrigerant. ### Claim 13 (depends on 12) The heat pump system according to claim 12, further comprising: an aqueous medium circuit configured to circulate an aqueous medium to exchange heat with the usage-side refrigerant in said refrigerant/water heat exchanger, the aqueous medium circuit having said radiation amount adjusting element, which is a variable-capacity circulation pump, a subcooling-degree fixing control being performed in which a degree of subcooling of said heat-source-side refrigerant in said first usage-side heat exchanger is fixed at a predetermined degree of subcooling by adjusting an opening degree of said first usage-side flow rate adjustment valve, and a capacity of said circulation pump being controlled so that a flow rate of the aqueous medium circulated through said aqueous medium circuit decreases in a case in which said first usage-side flow rate adjustment valve reaches an opening degree equal to or greater than a predetermined opening degree. ### Claim 14 (depends on 13) The heat pump system according to claim 13, further comprising: a discharge refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from a discharge of said heat-source-side compressor in any of said heat-source-side radiating operation state and said heat-source-side evaporating operation state of said heat-source-side switching mechanism; a liquid refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from an outlet of said heat-source-side heat exchanger functioning as a radiator of the heat-source-side refrigerant in said heat-source-side radiating operation state of said heat-source-side switching mechanism, and introducing the heat-source-side refrigerant into an inlet of said heat-source-side heat exchanger functioning as an evaporator of the heat-source-side refrigerant from outside said heat source unit in said heat-source-side evaporating operation state of said heat-source-side switching mechanism; and a gas refrigerant communication tube capable of introducing the heat-source-side refrigerant into an intake of said heat-source-side compressor from outside said heat source unit. ### Claim 15 (depends on 12) The heat pump system according to claim 12, further comprising: a discharge refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from a discharge of said heat-source-side compressor in any of said heat-source-side radiating operation state and said heat-source-side evaporating operation state of said heat-source-side switching mechanism; a liquid refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from an outlet of said heat-source-side heat exchanger functioning as a radiator of the heat-source-side refrigerant in said heat-source-side radiating operation state of said heat-source-side switching mechanism, and introducing the heat-source-side refrigerant into an inlet of said heat-source-side heat exchanger functioning as an evaporator of the heat-source-side refrigerant from outside said heat source unit in said heat-source-side evaporating operation state of said heat-source-side switching mechanism; and a gas refrigerant communication tube capable of introducing the heat-source-side refrigerant into an intake of said heat-source-side compressor from outside said heat source unit. ### Claim 16 (depends on 1) The heat pump system according to claim 1, further comprising: a discharge refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from a discharge of said heat-source-side compressor in any of said heat-source-side radiating operation state and said heat-source-side evaporating operation state of said heat-source-side switching mechanism; a liquid refrigerant communication tube capable of directing the heat-source-side refrigerant outside of said heat source unit from an outlet of said heat-source-side heat exchanger functioning as a radiator of the heat-source-side refrigerant in said heat-source-side radiating operation state of said heat-source-side switching mechanism, and introducing the heat-source-side refrigerant into an inlet of said heat-source-side heat exchanger functioning as an evaporator of the heat-source-side refrigerant from outside said heat source unit in said heat-source-side evaporating operation state of said heat-source-side switching mechanism; and a gas refrigerant communication tube capable of introducing the heat-source-side refrigerant into an intake of said heat-source-side compressor from outside said heat source unit.