A refrigerant amount management system manages an amount of refrigerant with which a plurality of refrigeration cycle apparatuses is filled. Each refrigeration cycle apparatus has a refrigerant circuit. The refrigerant amount management system includes an additional-filling-amount obtaining unit that obtains an additional filling amount of refrigerant with which a refrigeration cycle apparatus has been additionally filled after installation, a storage unit, and a useful-information creation unit. The storage unit stores apparatus information regarding the refrigeration cycle apparatus that has been additionally filled with refrigerant and the additional filling amount of the refrigeration cycle apparatus identified with the apparatus information in association with each other. The useful-information creation unit creates useful information to be used in management of the amount of refrigerant based on the additional filling amount of one of the refrigeration cycle apparatuses and the additional filling amount of another of the refrigeration cycle apparatuses.

The amount of refrigerant to be charged in a refrigerant circuit of an air conditioner is set to a range defined by a lower-limit charge amount and an upper-limit charge amount. The lower-limit charge amount is a charge amount with which a refrigerant supercooling degree is 0 deg and a refrigerant quality is 0 at a refrigerant outlet side of a supercooling heat exchanger when a cooling operation is performed under an overload condition in which the refrigerant is hardly condensed in an outdoor heat exchanger that functions as a condenser. On the other hand, the upper-limit charge amount is a charge amount with which a refrigerant supercooling degree is 0 deg and a refrigerant quality is 0 at a refrigerant outlet side of the outdoor heat exchanger when the cooling operation is performed under a rated condition.

A refrigerant amount management system manages an amount of refrigerant with which a plurality of refrigeration cycle apparatuses is filled. Each refrigeration cycle apparatus has a refrigerant circuit. The refrigerant amount management system includes an additional-filling-amount obtaining unit that obtains an additional filling amount of refrigerant with which a refrigeration cycle apparatus has been additionally filled after installation, a storage unit, and a useful-information creation unit. The storage unit stores apparatus information regarding the refrigeration cycle apparatus that has been additionally filled with refrigerant and the additional filling amount of the refrigeration cycle apparatus identified with the apparatus information in association with each other. The useful-information creation unit creates useful information to be used in management of the amount of refrigerant based on the additional filling amount of one of the refrigeration cycle apparatuses and the additional filling amount of another of the refrigeration cycle apparatuses.

The present invention provides a cooling system including a vaporizer (1) which is configured to absorb heat due to a liquid-phase refrigerant R being vaporized, a condenser (2) which is configured to discharge heat due to a refrigerant (R) in a gaseous phase state being liquefied, a resistance body (8) which is provided in a middle of a pipe passage (3) ranging from the vaporizer (1) to the condenser (2) and is configured to apply a resistance to the refrigerant (R), state detection sensors (9) which are provided in the pipe passage (3) on an upstream side and a downstream side of the resistance body (8) and are configured to detect a state of the refrigerant (R) flowing through each side inside the pipe passage (3), and a flow rate control means (C) which is configured to detect the presence of droplets in the refrigerant R flowing through the pipe passage (3) on the basis of a difference between detection values of the state detection sensors (9) which are detected on the upstream side and the downstream side of the resistance body (8), and controls a flow rate of the refrigerant (R) on the basis of detection results.

There is provided an air conditioner capable of displaying sufficient cooling ability in each indoor unit by allowing a sufficient amount of refrigerant to flow into indoor units where cooling ability cannot be displayed. By executing refrigerant amount balance control, since degrees of opening of indoor expansion valves are narrowed in indoor units whose refrigerant superheating degrees are smaller than an average refrigerant superheating degree, amounts of refrigerant flowing into the indoor expansion valves are decreased. In the indoor unit where the refrigerant superheating degree is higher than the average refrigerant superheating degree, since refrigerant pressure on a downstream side of the indoor expansion valve is also decreased due to the degrees of opening of the indoor expansion valves being narrowed, the difference in pressure between the upstream side and the downstream side of the indoor expansion valve increases and an amount of refrigerant flowing into the indoor unit is increased.

Provided is an air conditioning apparatus. The air conditioning apparatus includes an outdoor unit which includes a compressor and an outdoor heat exchanger and through which a refrigerant is circulated, an indoor unit through which water is circulated, a heat exchanger in which the refrigerant and the water are heat-exchanged with each other, a water tube configured to guide the water circulated through the indoor unit and the heat exchanger, a pump installed in the water tube, and a controller configured to analyze an output signal of the pump so as to calculate a ration of an air layer in the water tube, the controller being configured to control a target supercooling degree or target superheating degree of the heat exchanger according to the calculated ratio of the air layer.

A CO2 refrigeration system can include a condenser, multiple fans, and a controller. The condenser can be configured to cool CO2 and the multiple fans can be configured to affect cooling operations of the condenser. The controller may be configured to obtain a temperature value of CO2 output by the condenser. The controller may be configured to determine if the condenser is operating properly using the temperature value of the CO2. The controller may be configured to obtain values of input current and input voltage provided to the multiple fans. The controller can determine a number of in-operational or faulty fans of the multiple fans using, at least in part, the values of the input current and the input voltage and a model that relates input current to input voltage for known numbers of in-operational or faulty fans.

A CO2 refrigeration system can include a condenser, multiple fans, and a controller. The condenser can be configured to cool CO2 and the multiple fans can be configured to affect cooling operations of the condenser. The controller may be configured to obtain a temperature value of CO2 output by the condenser. The controller may be configured to determine if the condenser is operating properly using the temperature value of the CO2. The controller may be configured to obtain values of input current and input voltage provided to the multiple fans. The controller can determine a number of in-operational or faulty fans of the multiple fans using, at least in part, the values of the input current and the input voltage and a model that relates input current to input voltage for known numbers of in-operational or faulty fans.

An air-conditioning apparatus includes a refrigerant circuit in which an outdoor unit, at least one load-side expansion device, and at least one load-side heat exchanger are connected by pipes to allow refrigerant to circulate. The outdoor unit includes a compressor including an injection port allowing the refrigerant to flow into a suction chamber, a heat-source-side heat exchanger for heat exchange for the refrigerant, and an accumulator. The load-side heat exchanger transfers heat between a load and the refrigerant. The outdoor unit includes: an injection pipe having one end connected between the heat-source-side heat exchanger and the load-side expansion device, and the other end connected to the injection port, in the refrigerant circuit; an outdoor-side expansion device located downstream from the one end of the injection pipe in the flow of the refrigerant from the load-side expansion device to the heat-source-side heat exchanger; and an injection expansion device that adjusts the amount of the refrigerant flowing through the injection pipe. Also, a controller is provided to control the opening degrees of the outdoor-side expansion device and the injection expansion device.

A regulation method for an inverter compressor in a refrigeration system including establishing a working area via limit values for evaporation temperatures, condensation temperatures, compressor speeds, maximum compression ratio, and maximum superheat value, and measuring working values of the compressor in terms of evaporation temperature, condensation temperature, and compression ratio. If the compressor operates outside the established working area, the method includes modifying the working parameters of the compressor by acting on elements to be selected among the compressor speed, the opening angle of the expansion valve, and a combination thereof. If the compressor does not go back to the working area within a certain time, the method includes stopping operation of the compressor and triggering an alarm.