Abstract: An air conditioning system includes an air conditioning apparatus, and a controller. The air conditioning apparatus performs air conditioning of an air-conditioning target space. The controller is connectable to a plurality of types of thermostats. The controller performs communication with the thermostat connected thereto. The controller performs a performance determination process for the refrigeration cycle apparatus. The controller performs different performance determination processes according to whether a first type of thermostat is connected thereto unit or whether a second type of thermostat is connected thereto. Alternatively, the air conditioning apparatus changes a method for using information received by the controller from the thermostat according to whether being in a determination processing time over which the performance determination process is performed or in a non-determination processing time over which the performance determination process is not performed.

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.

Abstract: A refrigerant-amount determination kit includes a sensor and a processor. The sensor is mounted at least temporarily on at least one of a portion of a refrigeration cycle apparatus and the periphery of the refrigeration cycle apparatus. The refrigeration cycle apparatus is an apparatus having a refrigerant circuit that includes a compressor, a condenser, and an evaporator. The processor determines the amount of a refrigerant in the refrigerant circuit based on a detection result detected by the sensor during operation of the refrigeration cycle apparatus.

Abstract: Providing a refrigerant circuit apparatus evaluation system, which, when a plurality of refrigerant circuit apparatuses is installed, may accurately determine whether a heat source unit of each refrigerant circuit apparatus adversely affects the operation of a different refrigerant circuit apparatus. A refrigerant circuit apparatus evaluation system includes memory and processing circuitry. The processing circuitry acquires operation data on a first air-conditioning apparatus. The first air-conditioning apparatus includes a first heat source unit. The processing circuitry determines whether an operation of a second heat source unit different from the first heat source unit has an adverse effect on an operation of the first heat source unit based on the operation data on the first air-conditioning apparatus acquired by the processing circuitry when the first air-conditioning apparatus and a second air-conditioning apparatus including the second heat source unit are simultaneously operating.

Abstract: An air conditioning system includes an air conditioning apparatus, and a controller. The air conditioning apparatus performs air conditioning of an air-conditioning target space. The controller is connectable to a plurality of types of thermostats. The controller performs communication with the thermostat connected thereto. The controller performs a performance determination process for the refrigeration cycle apparatus. The controller performs different performance determination processes according to whether a first type of thermostat is connected thereto unit or whether a second type of thermostat is connected thereto. Alternatively, the air conditioning apparatus changes a method for using information received by the controller from the thermostat according to whether being in a determination processing time over which the performance determination process is performed or in a non-determination processing time over which the performance determination process is not performed.

Abstract: An apparatus evaluation system includes a first evaluation unit that evaluates a first air conditioning apparatus, and a first air conditioning control unit that controls a second air conditioning apparatus. The first evaluation unit performs a first evaluation process to evaluate the first air conditioning apparatus based on a first evaluation index obtained in a first operation performed as a first evaluation operation at a time of installation, and a second evaluation process to evaluate the first air conditioning apparatus based on the first evaluation index obtained in a second operation performed as the first evaluation operation after the first evaluation process. The control unit operates the second air conditioning apparatus before at least one of the first and second operations of the first air conditioning apparatus is performed, and/or while at least one of the first and second operations of the first air conditioning apparatus is being performed.

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.

Abstract: A refrigerant-amount determination kit includes a sensor and a processor. The sensor is mounted at least temporarily on at least one of a portion of a refrigeration cycle apparatus and the periphery of the refrigeration cycle apparatus. The refrigeration cycle apparatus is an apparatus having a refrigerant circuit that includes a compressor, a condenser, and an evaporator. The processor determines the amount of a refrigerant in the refrigerant circuit based on a detection result detected by the sensor during operation of the refrigeration cycle apparatus.

Abstract: A heat pump system includes a heat pump circuit, a load distribution element, and a controller. The heat pump circuit includes low-stage and high-stage compression mechanisms having a fixed capacity ratio relationship. The load distribution element establishes a load distribution between first and second heat loads subjected to heating processes by heat exchange with refrigerant discharged from the low-stage and high-stage compression mechanisms, respectively. The controller performs distribution control to maintain a ratio of 1 between temperatures of the refrigerant discharged from the low-stage and high stage compression mechanisms and after heat exchange with the first and second heat loads, respectively. Alternatively, the controller performs distribution control to reduce a difference between the temperatures of the refrigerant discharged from the low-stage and high stage compression mechanisms and after heat exchange with the first and second heat loads, respectively.

Abstract: A refrigeration apparatus includes a compression mechanism, a heat source-side heat exchanger, a usage-side heat exchanger, an intercooler, an intercooler bypass tube and an intake return tube. The compression mechanism has a plurality of compression elements configured so that refrigerant discharged from a first-stage compression element is sequentially compressed by a second-stage compression element. The intercooler is connected to an intermediate refrigerant tube configured to draw refrigerant discharged from the first-stage compression element into the second-stage compression element to cool the refrigerant discharged from the first-stage compression element and drawn into the second-stage compression element. The intercooler bypass tube is connected to the intermediate refrigerant tube so as to bypass the intercooler.

Abstract: A heat pump system includes a heat pump circuit, a heat load circuit, first and second heat exchangers, a flow rate regulation mechanism and a controller. A first passage connects branching and converging portions of the heat load circuit. A second passage connects the branching and converging portions without converging with the first passage. The first and second heat exchanger perform heat exchange between discharge refrigerant from the low and high stage compression mechanisms and fluid in the first and second passages, respectively. The flow rate regulation mechanism regulates a ratio between flow rates through the first and second passages. The controller controls the flow rate regulation mechanism so that the fluid is allowed to flow to the first heat exchanger when a temperature of refrigerant flowing into the first heat exchanger is lower than a heating target temperature of converged fluid flowing through the heat load circuit.

Abstract: A refrigerating apparatus, where refrigerant reaches a supercritical state in at least part of a refrigeration cycle, includes at least one expansion mechanism, an evaporator connected to the expansion mechanism, first and second sequential compression elements, a radiator connected to the discharge side of the second compression element, a first refrigerant pipe interconnecting the radiator and the expansion mechanism, a heat exchanger arranged to cause heat exchange between the first refrigerant pipe and another refrigerant pipe. Preferably, a heat exchanger switching mechanism is switchable so that refrigerant flows in the first refrigerant pipe through the first heat exchanger or in a heat exchange bypass pipe connected to the first refrigerant pipe.

Abstract: A refrigeration apparatus includes a multi-stage compression mechanism, heat source-side and usage side heat exchangers each operable as a radiator/evaporator, a switching mechanism switchable between cooling and heating operation states, a second-stage injection tube, an intermediate heat exchanger and an intermediate heat exchanger bypass tube. The intermediate heat exchanger bypass tube ensures that refrigerant discharged from the first-stage compression element and drawn into the second-stage compression element is not cooled by the intermediate heat exchanger during a heating operation. Injection rate optimization controls a flow rate of refrigerant returned to the second-stage compression element through the second-stage injection tube so that an injection ratio is greater during the heating operation than during a cooling operation.

Abstract: A heat pump system includes a heat pump circuit, a heat load circuit, first and second heat exchangers, a flow rate regulation mechanism and a controller. A first passage connects branching and converging portions of the heat load circuit. A second passage connects the branching and converging portions without converging with the first passage. The first and second heat exchanger perform heat exchange between discharge refrigerant from the low and high stage compression mechanisms and fluid in the first and second passages, respectively. The flow rate regulation mechanism regulates a ratio between flow rates through the first and second passages. The controller controls the flow rate regulation mechanism so that the fluid is allowed to flow to the first heat exchanger when a temperature of refrigerant flowing into the first heat exchanger is lower than a heating target temperature of converged fluid flowing through the heat load circuit.

Abstract: A heat pump system includes a heat pump circuit, a load distribution element, and a controller. The heat pump circuit includes low-stage and high-stage compression mechanisms having a fixed capacity ratio relationship. The load distribution element establishes a load distribution between first and second heat loads subjected to heating processes by heat exchange with refrigerant discharged from the low-stage and high-stage compression mechanisms, respectively. The controller performs distribution control to maintain a ratio of 1 between temperatures of the refrigerant discharged from the low-stage and high stage compression mechanisms and after heat exchange with the first and second heat loads, respectively. Alternatively, the controller performs distribution control to reduce a difference between the temperatures of the refrigerant discharged from the low-stage and high stage compression mechanisms and after heat exchange with the first and second heat loads, respectively.

Abstract: An air-conditioning apparatus uses carbon dioxide as a refrigerant, and includes a two-stage-compression-type compression mechanism, a heat source-side heat exchanger, an expansion mechanism, a usage-side heat exchanger, and an intercooler. The intercooler uses air as a heat source. The intercooler is configured and arranged to cool refrigerant flowing through an intermediate refrigerant tube that draws refrigerant discharged from the first-stage compression element into the second-stage compression element. The intercooler is integrated with the heat source-side heat exchanger to form an integrated heat exchanger, with the intercooler disposed in an upper part of the integrated heat exchanger.

Abstract: A refrigeration apparatus uses a refrigerant that operates in a supercritical range. The refrigeration apparatus includes a compression mechanism, a heat source-side heat exchanger, an expansion mechanism, a usage-side heat exchanger, a switching mechanism, an intercooler which functions as a cooler of refrigerant discharged from a first-stage compression element of the compression mechanism and drawn into a second-stage compression element of the compression mechanism, and an intercooler bypass tube. The switching mechanism is configured to switch between cooling and heating operation states in which refrigerant is circulated differently. When a defrosting operation for defrosting the heat source-side heat exchanger is performed, refrigerant flows to the heat source-side heat exchanger and the intercooler. After defrosting of the intercooler is detected as being complete, the intercooler bypass tube is used to ensure that the refrigerant does not flow to the intercooler.

Abstract: A refrigeration apparatus uses a refrigerant that operates in a supercritical range. The refrigeration apparatus includes a compression mechanism, a heat source-side heat exchanger, an expansion mechanism, a usage-side heat exchanger, a switching mechanism, an intercooler, a bypass tube, and an injection tube. The switching mechanism is configured to switch between cooling and heating operation states. When the switching mechanism is switched to the cooling operation state to allow refrigerant to flow to the heat source-side heat exchanger and a reverse cycle defrosting operation for defrosting the heat source-side heat exchanger is performed, the refrigerant is caused to flow to the heat source-side heat exchanger, the intercooler and the injection tube. After the defrosting of the intercooler is detected as being complete, the bypass tube is used so as to ensure that the refrigerant does not flow to the intercooler and the injection valve is controlled so that the opening degree is increased.

Abstract: A refrigeration apparatus uses a refrigerant that operates in a region including critical processes, and includes a compression mechanism having first and second compressors, a heat-source-side heat exchanger, an expansion mechanism, a utilization-side heat exchanger, an intercooler, and an intermediate refrigerant pipe. The first compressor has a first low-pressure compression element and a first high-pressure compression element to increase pressure of refrigerant more than the first low-pressure compression element. The second compressor has a second low-pressure compression element and a second high-pressure compression element to increase pressure of refrigerant more than the second low-pressure compression element. The intermediate refrigerant pipe causes refrigerant discharged by the first and second low-pressure compression elements to pass through the intercooler and be sucked into first and second high-pressure the compression elements.

Abstract: A heat pump system includes a heat pump circuit, a heat load circuit, first and second heat exchangers, a flow rate adjustment element, and a controller. The heat pump circuit circulates primary refrigerant through a low and high stage-side compression elements, an expansion element and an evaporator. The heat load circuit circulates a first fluid and has a first and second branching portions, first and second branching channels, and a heat-load-processing section. The first and second heat exchangers perform heat exchange between the primary refrigerant and the first fluid. Flow rate of the first fluid in the first and/or second branching channel is adjustable. The controller performs flow rate adjustment control so as to maintain a state in which a predetermined temperature condition is satisfied, or to reduce a difference between the temperature of the first fluid flowing through portions of the first and second branching channels.