A computing device calculates an evaporating temperature Te* and a dew-point temperature Tdew* from a quality X, a temperature glide ΔT determined by a difference between a boiling temperature and a dew-point temperature at a predetermined pressure, and a refrigerant temperature detected by second temperature detection device.

A refrigeration system includes a subcooler configured to provide subcooling for a liquid refrigerant flowing through a first side of the subcooler by transferring heat from the liquid refrigerant to a gas refrigerant flowing through a second side of the subcooler. An expansion valve is located at an inlet of the second side of the subcooler and configured to control a flow of the gas refrigerant through the second side of the subcooler. A gas temperature sensor and a gas pressure sensor are configured to measure a temperature and pressure of the gas refrigerant. A liquid temperature sensor is configured to measure a temperature of the subcooled liquid refrigerant. A controller is configured to calculate a superheat of the gas refrigerant based on the measured temperature and measured pressure of the gas refrigerant and may compare the calculated superheat to a superheat threshold. If the calculated superheat is less than the superheat threshold, the controller may close the expansion valve. If the calculated superheat is equal to or greater than the superheat threshold, the controller may operate the expansion valve using a feedback control technique to drive the temperature of the subcooled liquid refrigerant to a subcooled liquid temperature setpoint.

An air-conditioning apparatus detects refrigerant leak with high-accuracy even in a state in which an excessive liquid refrigerant is stored in an accumulator. The air-conditioning apparatus determines that leakage of refrigerant has occurred from a refrigerant circuit in an operating state in which an excessive liquid refrigerant is stored in an accumulator, after a part of the excessive liquid refrigerant stored in the accumulator is moved and stored into a condenser, with the excessive liquid refrigerant remaining in the accumulator as a reference amount, when the excessive liquid refrigerant is less than the reference amount.

A method including: determining whether a cooling system is operating in a cooling mode, such that the cooling system is not operating in a reheat mode, a humidification mode or a dehumidification mode; determining whether the cooling system is operating in a compressor mode, such that the cooling system is not operating in a pump refrigerant economization mode; determining whether the cooling system is at steady-state; and if the cooling system is operating in the cooling mode and the compressor mode and is at steady-state, evaluating one or more rules to determine if a degradation symptom exists for the cooling system. The method further includes: subsequent to the evaluation, generating a degradation evaluation value to indicate whether the one or more rules are satisfied; and based on the degradation evaluation value, generating an alarm signal or performing a countermeasure.

A method for preventing formation of droplets in a heat exchanger, in which a second medium transfers heat to a first. The method is performed by a controller which receives different temperature values (T.sub.1, T.sub.2, T.sub.3) and a pressure (P) value to be used for calculating a boiling point temperature value (T.sub.B) and determining a first temperature difference (ΔT.sub.1) and a second temperature difference (ΔT.sub.2). Generating a flow control signal, for controlling the flow of the first medium into the heat exchanger, based on the first temperature difference (ΔT.sub.1), the second temperature difference (ΔT.sub.2) and the first temperature value T.sub.1 and sending the flow control signal to a regulator device for controlling the flow of the first medium in the heat exchanger.

A temperature control system according to one embodiment includes: a refrigeration apparatus in which a compressor, a condenser, an expansion valve and an evaporator are connected in this order for circulating a refrigerant; a fluid circulation apparatus that causes a fluid to be heat-exchanged in the evaporator, then sends the fluid to a temperature control object, and again causes the fluid having passed through the temperature control object to be heat-exchanged in the evaporator, the fluid circulation apparatus having a heater at a position downstream of the temperature control object and upstream of the evaporator; and a control apparatus. The control apparatus activates the heater to heat the fluid by the heater, when the fluid circulation apparatus has become in a no-load operation state or a no-load-operation transition operation state, wherein the no-load operation state is a state in which the fluid and the temperature control object do not heat-exchange, the no-load-operation transition operation state is a state that is in transition to the no-load operation state.

A refrigeration system with pressure balancing function includes a condensing unit, a first refrigerant delivery pipeline, and a pressure balance control device including a temperature control unit, a first refrigerant control valve and a refrigerant supply switching controller. The temperature control unit determines if the temperature of the evaporator is abnormal, generates a temperature adjustment trigger signal that shifts between adjustment level and non-adjustment level. The refrigerant supply switching controller will determine, based on the level of the temperature adjustment trigger signal, whether to output the valve-open signal to the first refrigerant control valve. When the temperature adjustment trigger signal received by the refrigerant supply switching controller is at the adjustment level, the refrigerant supply switching controller will not output the valve-open signal to the first refrigerant control valve, so that the first refrigerant control valve is closed to stop delivering the refrigerant to the first refrigerant delivery pipeline.

An air conditioner includes an outdoor unit and a plurality of indoor units connected to the outdoor unit. The outdoor unit sometimes sets an evaporation temperature or a condensation temperature that is different from a value that any of the indoor units has requested from the outdoor unit. The indoor units have indoor-side controllers that perform capacity control that adjusts capacity based on a degree of superheating or a degree of supercooling, an air volume, or an evaporation temperature or a condensation temperature while calculating a requested capacity that is determined from a current room temperature and a set room temperature. The indoor-side controllers, when performing the capacity control, determine at least one of the air volume and a target value of the degree of superheating or the degree of supercooling based on the evaporation temperature or the condensation temperature that is set by the outdoor unit.

A method for conditioning air in a test space of a test chamber which receives test material. A temperature in a range of −20° C. to +180° C. is established within the test space with a cooling device. The cooling device includes a cooling circuit with a refrigerant, a heat exchanger, a compressor, a condenser and an expansion element. An internal heat exchanger of the cooling circuit is connected to a high-pressure side of the cooling circuit upstream of the expansion element and downstream of the condenser and to a low-pressure side of the cooling circuit upstream of the compressor and downstream of the heat exchanger and is used to cool the refrigerant of the high-pressure side. A zeotropic refrigerant is used and the internal heat exchanger is used to cool the refrigerant of the high-pressure side to lower an evaporation temperature at the expansion element.

The present disclosure relates to an adjustable fluid flow system for a temperature control system having a heat exchanger including a plurality of channels configured to transmit working fluid and direct the working fluid through a selection of two or more channel sections. The adjustable fluid flow system includes a first chamber defining a first flow path that is aligned with a first channel section of the two or more channel sections, wherein the first chamber includes a first outlet in fluid communication with the first flow path, and a second chamber defining a second flow path that is aligned with a second channel section of the two or more channel sections, wherein the second chamber includes a second outlet in fluid communication with the second flow path. The adjustable fluid flow system further includes a damper configured to adjust a flow of air along the first flow path.