Abstract: A heat medium relay device includes a valve block provided in a third space, and including a plurality of valves to allow a secondary heat medium subjected to the heat exchange at a first heat exchanger and a secondary heat medium subjected to the heat exchange at a second heat exchanger to flow to at least one indoor unit, the valve block being lighter in weight than each of the first heat exchanger, a first pump, the second heat exchanger, and a second pump.

Abstract: Disclosed is a scroll compressor including: an orbiting scroll having an orbiting scroll end plate and an orbiting volute formed on one side of the orbiting scroll end plate, and a fixed scroll having a fixed scroll end plate and a fixed volute formed on one side of the fixed scroll end plate. The fixed and orbiting scrolls match each other in order to form a series of compression cavities therebetween including a central compression cavity and middle compression cavities located radially outside of the central compression cavity, and. The middle compression cavities include at least a set of a first middle compression cavity and a second middle compression cavity. A fluid channel selectively communicating with a discharge area is provided between the first and second middle compression cavities, and the first middle compression cavity directly communicates with the second middle compression cavity by means of the fluid channel.

Abstract: In an air-conditioning apparatus, an outdoor unit installed in an outdoor space and an indoor unit installed in an indoor space are connected by refrigerant pipes to form a refrigerant circuit. One or more pairs of valve kits are provided at the refrigerant pipes by which the outdoor unit and the indoor unit are connected, and allow a pair of additional refrigerant pipes on an inflow side and an outflow side to be connected to one of the one or more pairs of valve kits, the pair of additional refrigerant pipes being additionally provided to enable a new indoor unit to be added after installation of the air-conditioning apparatus. The valve kits of the one or more pairs of valve kits have respective distal end portions that are inclined upwards relative to a horizontal direction. The distal end portions each allow an associated one of the additional refrigerant pipe to be connected to the distal end portion.

Abstract: A multi-air conditioner for heating and cooling may include at least one indoor unit, an outdoor unit, and at least one leak shut-off valve. The at least one indoor unit is installed in an indoor space and includes an indoor heat exchanger and an indoor expansion valve. The outdoor unit is connected to the at least one indoor unit via a refrigerant pipeline and includes an outdoor heat exchanger, a compressor, an outdoor expansion valve, and a four-way valve. The outdoor unit may decrease a pressure of the refrigerant pipeline when a refrigerant leak occurs from the refrigerant pipeline. The at least one leak shut-off valve is provided on the refrigerant pipeline and blocks a flow of refrigerant in the refrigerant pipeline when a refrigerant leak from the refrigerant pipeline occurs in the indoor space.

Abstract: An air conditioning apparatus includes: a second heat exchanger; a plurality of third heat exchangers; and a plurality of flow rate control valves. In a defrosting mode, when a heat exchanger that is not being requested to perform air conditioning includes a first device having a set temperature lower than or equal to a current room temperature and a second device which is set so as not to perform air conditioning, a controller is configured to control a first flow rate control valve corresponding to the first device and a second flow rate control valve corresponding to the second device such that a degree of opening of the first flow rate control valve is higher than or equal to a degree of opening of the second flow rate control valve.

Abstract: A heat pump system for a vehicle is configured for eliminating a chiller which is separately configured, adjusting a temperature of a battery module by use of an evaporator where a coolant and a refrigerant exchange heat, and improving heating performance by use of a sub-centralized energy module together with waste heat of electrical equipment in a heating mode of the vehicle.

Abstract: A heat management system disclosed herein is used for a vehicle. The heat management system may include an electric device, a first heat exchanger, a second heat exchanger, a first channel, a second channel, a first pump, a second pump, a first channel valve, a second channel valve, a bypass channel, and a controller. The controller may be configured to, when one of the first pump and the second pump operates abnormally, control the first channel valve and the second channel valve such that the flow of the first heat medium from both of the first channel and the second channel to the first heat exchanger is allowed and activate the other of the first pump and the second pump.

Abstract: A two-pipe enhanced-vapor-injection outdoor unit and a multi-split system are provided. The two-pipe enhanced-vapor-injection outdoor unit includes: an outdoor heat exchanger and a second port; an enhanced-vapor-injection compressor, including a gas discharge port, a gas return port and an injection port; a reversing assembly, including first to fourth ends; a supercooler, including a main heat-exchange flow path and an auxiliary heat-exchange flow path communicated with each other, the main heat-exchange flow path being connected to the second port, the auxiliary heat-exchange flow path being connected to the injection port; and a throttling assembly having a first end connected to an outlet of the main heat-exchange flow path, and a second end connected to an inlet of the outdoor heat exchanger.

Abstract: A control method of a transcritical carbon dioxide composite heat pump system is disclosed, wherein the transcritical carbon dioxide composite heat pump system includes: a CO2 main circuit compressor, an air-cooling-air-cooling recombiner, a supercooling-evaporation recombiner, an evaporator and a CO2 auxiliary compressor; wherein the air-cooling-air-cooling recombiner comprises a CO2 main circuit, a CO2 auxiliary circuit and a water circuit; the supercooling-evaporation recombiner comprises a CO2 main circuit supercooling section and a CO2 auxiliary circuit evaporation section. The present invention includes two working modes according to the return water temperature, so that the unit has a wider application range and meets daily needs. There is only one heat exchanger for refrigerant and water. Compared with the three water and refrigerant heat exchangers in the conventional transcritical CO2 composite heat pump, the circulating water circuit is a single circuit with one inlet and one outlet.

Abstract: A heat source unit for an air conditioner that includes a refrigerant circuit includes: an external housing; and a cooling heat exchanger that is disposed in the external housing and that is connected to the refrigerant circuit. The external housing accommodates: a compressor connected to the refrigerant circuit; a heat source heat exchanger that is connected to the refrigerant circuit and that exchanges heat between a refrigerant circulating in the refrigerant circuit and a heat source; and an electric box. The electric box includes a top and a plurality of side walls; accommodates electrical components that control the air conditioner; and further includes an air passage that includes an air inlet and an air outlet. An air flow is induced through the air passage from the air inlet to the air outlet for cooling at least some of the electrical components.

Abstract: An air-conditioning system includes a heat-source device that includes a compressor and a heat-source-side heat exchanger, a relay device that includes a pump and an intermediate heat exchanger, and a plurality of indoor units that each include a load-side heat exchanger. The air-conditioning system includes a refrigerant circuit through which refrigerant circulates and a heat medium circuit through which a heat medium circulates. The air-conditioning system includes a flow rate detection unit configured to detect flow rate information associated with a flow rate of a heat medium that flows through each of the plurality of indoor units and a controller configured to control the compressor and the pump. The controller controls operation of at least either the compressor or the pump on the basis of the flow rate information detected by the flow rate detection unit.

Abstract: A vehicle includes: a vehicle main body having a passenger compartment and a rear compartment located more rearward than the passenger compartment; a rear hatch provided on the vehicle main body and configured to open and close the rear compartment; a cooling box disposed in the rear compartment; a first communication device configured to communicate with an external server; a second communication device having a communication distance shorter than that of the first communication device; a locking device configured to lock the rear hatch; and a processor. The processor is configured to receive information about an opening signal from the server through the first communication device, and to open the rear hatch when the processor receives the opening signal through the second communication device.

Abstract: A refrigeration cycle device has a cooling heat exchanger, an evaporation-pressure control valve, an inside-air ratio adjuster, and a controller. The evaporation-pressure control valve controls an evaporation pressure of a refrigerant in the cooling heat exchanger. The inside-air ratio adjuster changes a ratio of an inside air to an entire volume of the air exchanging heat with the refrigerant in the cooling heat exchanger. The controller controls the inside-air ratio adjuster. The evaporation-pressure control valve increases the evaporation pressure of the refrigerant as a flow rate of the refrigerant flowing through the evaporation-pressure control valve increases. The controller, in a first mode, increases the ratio of the inside air as an evaporation temperature of the refrigerant in the cooling heat exchanger falls.

Abstract: In certain embodiments, a refrigeration system comprises an emergency electric power supply configured to supply power to at least one motor drive of the system. The system comprises a power switch coupled to the emergency electric power supply, a tank configured to store a refrigerant, a first compressor configured to compress the refrigerant of the tank, and a controller coupled to the power switch and first compressor. The controller may receive an indication from the power switch that the system is using the emergency electric power supply, and in response to receiving the indication from the power switch that the system is using the emergency electric power supply, operate the system in a first power outage mode. The controller may determine an amount of power to supply to the first compressor based on the first power outage mode and transmit a signal to instruct the first compressor to turn on.

Abstract: Provided is a air conditioner including high-and-low-pressure gas pipe expansion valves each of which is provided to a corresponding one of the cooling-heating switching units and adjusts feeding of high-temperature and high-pressure gas refrigerant to the corresponding indoor unit; and a refrigeration cycle controller which adjusts a valve opening degree of the high-and-low-pressure gas pipe expansion valve of the cooling-heating switching unit connected to one of the indoor units which is not in heating operation, in accordance with a determination result on excess or deficiency of refrigerant in a refrigeration cycle.

Abstract: A heat pump system comprises a compressor, a first heat exchanger, a second heat exchanger, a mode switching valve, a throttling element and a reservoir, wherein the throttling element is arranged on a flow path between the first heat exchanger and the second heat exchanger; and which further comprises a mode switching flow path in which a first flow path and a second flow path are arranged, the reservoir is arranged on the second flow path and each flow path is controllably opened or closed to realize different functional modes.

Abstract: The present disclosure provides a hybrid intercooler system integrated with an air conditioning system and a method of controlling the same. In accordance with the present disclosure, it is possible to stabilize the temperature of intake air passing through the inlet of an intercooler using a water cooling unit and increase the cooling efficiency of the intercooler using an air cooling unit. Consequently, it is possible to improve engine power and fuel efficiency.

Abstract: A controller controls a first air-conditioning system and a second air-conditioning system having separate refrigerant circuits, but arranged for conditioning a common space. The controller includes a multi-variable regulator to determine control signals for controlling operations of first components of the first and the second refrigerant circuits to reduce jointly and concurrently an environmental error between setpoint and measured values of environment in the common space. The controller also includes at least two single-variable regulators to receive operational errors between setpoint and measured values of an operation of a second component of the first and the second refrigerant circuits. The controller separately determines control signals for controlling the operation of different refrigerant circuits that reduce the operational errors.

Abstract: A vehicle air conditioning apparatus is provided that can prevent temperature variations of the air after the heat exchange in a radiator to reliably control the temperature of the air supplied to the vehicle interior. During the heating operation and the heating and dehumidifying operation, target degree of supercooling SCt when target air-blowing temperature TAO is a predetermined temperature or higher is set to SCt1 that is greater than SCt2 when the target air-blowing temperature TAO is lower than the predetermined temperature. When amount of air Ga supplied from indoor fan 12 is lower than a predetermined value, the target degree of supercooling SCt is corrected, which is set such that the degree of supercooling is lower than target degree of supercooling corrected when the amount of air Ga supplied from the indoor fan 12 is a predetermined value or higher.

Abstract: A pipe mounting structure of an embodiment allows a pipe, which is connected to an outlet side of an evaporator, to be mounted on a second passage of an expansion valve in such a manner that the pipe is inserted into an inlet port, and allows a pipe, which is connected to an inlet side of a compressor, to be mounted on the second passage in such a manner that the pipe is inserted into an outlet port. These pipes are mounted so that the pipes face each other with a shaft therebetween. The pipe mounting structure includes a natural vibration suppressing structure configured to prevent or suppress natural vibration of a gas column having antinodes of a standing wave at an open end of one of the pipes and an open end of the other pipe.

Abstract: An air-conditioning apparatus controls a decrease in efficiency of a refrigeration cycle, and includes a suction pipe having one end connected to a suction side of a compressor and an other end connected to an evaporator, a receiver connected to a refrigerant pipe connecting the evaporator and a condenser to each other, a first bypass pipe having one end connected to the receiver and an other end connected to the suction pipe and configured to supply refrigerant from the receiver to the suction pipe, a flow control valve provided to the first bypass pipe, a heat recovery portion disposed downstream of a portion of the suction pipe connected to the first bypass pipe, and a control device configured to control an opening degree of the flow control valve based on a degree of superheat of refrigerant in the heat recovery portion.

Abstract: A control system for a rod pumping unit is disclosed herein. The control system includes a memory device, a sensor, and a processor. The memory device is configured to store a velocity profile for controlling a sucker rod string of the rod pumping unit. The sensor is configured to take measurements for determining surface load of the sucker rod string. The processor is configured to gain access to the memory device and the velocity profile. The processor is further configured to determine a reference force. The processor is further configured to receive a measurement from the sensor and determine the surface load. The processor is further configured to compute a desired velocity for commanding the rod pumping unit. The desired velocity is computed based on a reference velocity from the velocity profile, the reference force, and the surface load.

Abstract: An operation control apparatus of air-conditioning apparatus having an outdoor unit and an indoor unit includes a controller programmed to execute energy conservation control of the air conditioning apparatus. The controller includes at least one required temperature calculation part calculating a required evaporation temperature or a required condensation temperature based on either a current amount of heat exchanged in a usage-side heat exchanger of the indoor unit and a greater amount of heat exchanged in the usage-side heat exchanger than the current amount, or an operating state amount that yields the current amount of heat exchanged in the usage-side heat exchanger and an operating state amount that yields the greater amount of heat exchanged in the usage-side heat exchanger than the current amount.

Abstract: A system includes a temperature sensor, a pressure sensor, and a controller. The temperature sensor measures a temperature of a refrigerant at a compressor. The compressor receives the refrigerant from a second compressor. The pressure sensor measures a pressure of the refrigerant at the compressor. The controller receives one or more of the measured temperature and the measured pressure and determines that one or more of the measured temperature and the measured pressure exceed a threshold. In response to that determination, the controller actuates a pulse valve coupled to a liquid injection line. The pulse valve controls the flow of a liquid refrigerant from a flash tank through the liquid injection line to mix with the refrigerant at the compressor.

Abstract: A vehicle air conditioning apparatus is provided that can prevent temperature variations of the air after the heat exchange in a radiator to reliably control the temperature of the air supplied to the vehicle interior. During the heating operation and the heating and dehumidifying operation, target degree of supercooling SCt when target air-blowing temperature TAO is a predetermined temperature or higher is set to SCt1 that is greater than SCt2 when the target air-blowing temperature TAO is lower than the predetermined temperature. When amount of air Ga supplied from indoor fan 12 is lower than a predetermined value, the target degree of supercooling SCt is corrected, which is set such that the degree of supercooling is lower than target degree of supercooling corrected when the amount of air Ga supplied from the indoor fan 12 is a predetermined value or higher.

Abstract: A vehicle air conditioning apparatus is provided that can prevent temperature variations of the air after the heat exchange in a radiator to reliably control the temperature of the air supplied to the vehicle interior. During the heating operation and the heating and dehumidifying operation, target degree of supercooling SCt when target air-blowing temperature TAO is a predetermined temperature or higher is set to SCt1 that is greater than SCt2 when the target air-blowing temperature TAO is lower than the predetermined temperature. When amount of air Ga supplied from indoor fan 12 is lower than a predetermined value, the target degree of supercooling SCt is corrected, which is set such that the degree of supercooling is lower than target degree of supercooling corrected when the amount of air Ga supplied from the indoor fan 12 is a predetermined value or higher.

Abstract: Systems and methods for controlling a heat engine system are provided. One method includes initiating flow of a working fluid through a working fluid circuit having a high pressure side and a low pressure side by controlling a pump to pressurize and circulate the working fluid through the working fluid circuit and determining a configuration of the working fluid circuit by determining which of a plurality of waste heat exchangers and which of a plurality of recuperators to position in the high pressure side of the working fluid circuit. The method also includes determining, based on the determined configuration of the working fluid circuit, for each of a plurality of valves, whether to position each respective valve in an opened position, a closed position, or a partially opened position and actuating each of the plurality of valves to the determined opened position, closed position, or partially opened position.

Abstract: An air-conditioning apparatus includes: a first bypass pipe connected to an inlet-side passage of an accumulator through a second expansion device, a second passage of a subcooling heat exchanger, and a first opening and closing device; a second bypass pipe branched from the first bypass pipe between the subcooling heat exchanger and the first opening and closing device and connected to an injection port of a compressor through a second opening and closing device; and a third bypass pipe branched from a refrigerant pipe between a heat source-side heat exchanger and a use-side heat exchanger and connected to the second bypass pipe between the second opening and closing device and the injection port of the compressor through a third expansion device.

Abstract: A method is provided for operating a system for the liquefaction of gas of the type comprising a main heat exchange vessel, a bundle for the gas to be liquefied extending through said MCHE and a refrigerant compression circuit of which a first end leads evaporated refrigerant from the vessel towards a compressor and a second end supplies the compressed and cooled refrigerant from the compressor towards the MCHE. For avoiding problems during heat up or during start up of the heat exchanger the pressure within the liquefaction system is controlled by regulating the amount of evaporated refrigerant in the liquefaction circuit.

Abstract: The present disclosure provides an air conditioner. The air conditioner includes a compressor; a sensor for measuring the compressors state configured to detect compressor state information that includes at least one of a pressure value and a saturation temperature of the compressor; and a controller configured to control air flow on the side of an indoor unit by comparing the compressor state information measured from the sensor and a threshold.

Abstract: An air-conditioning apparatus is capable of completing heat medium freeze prevention control more quickly by performing heat medium temperature rise control for raising the temperature of a cooled heat medium and includes a controller that adjusts a current opening degree of a bypass device at a bypass pipe to an opening degree, and that makes an adjustment such that the flow passage resistance in the case of the opening degree becomes equal to the flow passage resistance in the case of an opening degree before an expansion device is adjusted to a minimum opening degree.

Abstract: A cooling system for cooling a hybrid vehicle apparatus includes a compressor that circulates a refrigerant, a first heat exchanger that carries out heat exchange between the refrigerant and outside air, an expansion valve that reduces the pressure of the refrigerant, a second heat exchanger that carries out heat exchange between the refrigerant and air-conditioning air, a cooling portion that cools the hybrid vehicle apparatus using the refrigerant that flows between the heat exchanger and the expansion valve, a gas-liquid separator that separates the refrigerant that flows between the heat exchanger and the cooling portion into a liquid-phase refrigerant and a gas-phase refrigerant, and a liquid accumulator that is provided between the gas-liquid separator and the cooling portion, and that retains the liquid-phase refrigerant separated by the gas-liquid separator.

Abstract: An air-conditioning apparatus controls that a discharge temperature does not become too high with a refrigerant whose compressor discharge temperature readily rises, and thus suppress degradation of the refrigerant and a refrigerating machine oil. An injection pipe that injects a heat source side refrigerant into a compressor is installed, connected a pipe between a backflow prevention device and an opening and closing device installed on a branching pipe, and an aperture unit in the compressor.

Abstract: A refrigeration system having a cooling circuit, a heating circuit, a pressurizing receiver tank circuit, a pilot circuit and a liquid injection circuit wherein the hot gas line includes a solenoid valve that connects an outlet of a compressor to an outlet of a receiver tank, and wherein the liquid injection circuit includes a liquid injection solenoid that connects the outlet of the receiver tank to an outlet of an economizer.

Abstract: An air conditioning system includes: first and second utilization side heat exchangers and a heat source side heat exchanger respectively connected in series; a compressor connected between the first utilization side heat exchanger and the heat source side heat exchanger; an expansion valve connected between the first utilization side heat exchanger and the second utilization side heat exchanger; a pressure control device connected between the second utilization side heat exchanger and the heat source side heat exchanger; and a bypass valve connected between the expansion valve and the heat source side heat exchanger. The bypass valve provides a variable amount of liquid refrigerant flowing from the expansion valve to the heat source side heat exchanger. The pressure control device and the bypass valve cooperate with each other to keep a temperature of the compressor below a maximum allowable temperature predetermined for the compressor.

Abstract: A refrigerant container, which is in particular suitable for use in a cooling system designed for operation with a two-phase refrigerant, includes a receiving space for receiving a refrigerant that is disposed in an interior of the refrigerant container. Disposed in the receiving space of the refrigerant container is a heat exchanger allowing passage of a further refrigerant therethrough and being configured to remove heat from refrigerant in the liquid and/or gaseous state of aggregation that is received in the receiving space in order to supercool the refrigerant and/or convert the refrigerant to the liquid state of aggregation.

Abstract: A refrigeration apparatus uses R32 as refrigerant, and includes a compressor, a condenser, an expansion mechanism, an evaporator, a branch flow channel branching from a main refrigerant channel joining the condenser and the evaporator, a first opening adjustable valve disposed along the branch flow channel, an injection heat exchanger, a first injection channel, a refrigerant storage tank disposed along the main refrigerant channel, and a second injection channel. The injection heat exchanger exchanges heat between refrigerant in the main refrigerant channel and refrigerant passing through the first opening adjustable valve. The first injection channel guides refrigerant that flows in the branch flow channel and that exits from the injection heat exchanger to the compressor or the suction passage. The second injection channel guides a gas component of refrigerant accumulated inside the refrigerant storage tank to the compressor or the suction passage.

Abstract: A method and apparatus for controlling temperature of a compressor motor (170) having a motor cooling circuit in a refrigeration system (1014) is provided. The motor cooling circuit includes a second expansion valve (1043) providing fluid communication between the condenser and the compressor motor. The compressor motor (170) is in fluid communication with the refrigeration circuit (1014) between downstream of the first expansion valve (1040) and a compressor inlet. Refrigerant is provided as a cooling fluid to the motor cooling circuit. A primary PID loop (402) and a secondary PID loop (414) are used to control the temperature and the flow of refrigerant to the motor (170).

Abstract: A cooling system for a beverage comprises an enclosure for housing a beverage container, a cold plate through which the beverage flows, and a refrigeration system that controllably cools the enclosure and the cold plate in a differential manner. In preferred embodiments, preference is given during normal operation to cooling the cold plate, and only cooling the enclosure when the cold plate is determined to be at or below a desired temperature. In some embodiments a special defrost cycle warms the cold plate while continuing to cool the enclosure. Controls can be mechanical, electronic or any combination of the two, and preferably utilizes information from both pressure and temperature sensors.

Abstract: A chiller including a condenser having a refrigerant-storage vessel in fluid communication with a multichannel heat exchanger is disclosed. The chiller further includes a compressor, an evaporator and an expansion device connected in a refrigerant circuit. The refrigerant-storage vessel provides system volume for pump down operations.

Abstract: Provided is a heat source system that includes two heat source devices connected in series to a heat medium and can be efficiently operated. A heat source system (1) reduces the temperature of chilled water that is guided from a cooling load and has a predetermined return temperature Tr, to a predetermined supply temperature Ts, and supplies the chilled water to the cooling load. The heat source system (1) includes: a second centrifugal chiller (TR2) that reduces the temperature of the chilled water from the return temperature Tr to an intermediate temperature T2; a first centrifugal chiller (TR1) that reduces the temperature of the chilled water that has been reduced to the intermediate temperature T2 by the second centrifugal chiller (TR2), to the supply temperature Ts; and a control unit (9) that variably sets the intermediate temperature T2.

Abstract: A cooling device utilizes a vapor compression refrigeration cycle including a compressor, a condenser, a receiver, an expansion valve, an evaporator, and an accumulator to cool a heat source with a coolant. The receiver separates the coolant having been subjected to heat exchange by the condenser into gas and liquid. The accumulator separates the coolant having been subjected to heat exchange by the evaporator into gas and liquid. The cooling device opens a switch valve capable of bringing the receiver and the accumulator into communication with each other to move the coolant liquid in the accumulator to the receiver. The cooling device restores the pressure difference between the receiver and the accumulator after the movement of the coolant liquid to the pressure difference before the movement of the coolant liquid by a pressure regulating unit.

Abstract: A refrigeration cycle device includes a first refrigerant passage in which a compressor, a first solenoid valve, a four-way valve, an outdoor heat exchanger, a pressure reducing device, an indoor heat exchanger, and an accumulator are sequentially connected through pipes; a second refrigerant passage in which a second solenoid valve and a water refrigerant heat exchanger are sequentially connected to a pipe that connects a portion of a pipe between the compressor and the first solenoid valve to the pressure reducing device; heating means for heating a shell of the compressor; and a controller that performs control so as to close the first solenoid valve and the second solenoid valve in association with an operation of the compressor being stopped and so as to open the first solenoid valve when the heating means heats the compressor.

Abstract: A refrigeration system includes a compressor, a condenser, an expansion device, an evaporator, and an additional refrigerant vessel connected in a closed refrigerant loop. The additional refrigerant vessel is connected to the condenser at the high pressure side by a first valve and to the evaporator at a low pressure side by a second valve. A controller controls operation of the first valve and the second valve. Only one of the first valve and the second valve may be open at the same time. Refrigerant from the additional refrigerant vessel may be added to the closed refrigerant loop when the controller receives a low refrigerant level indication of in the evaporator. Refrigerant may also be removed from the closed refrigerant loop when the controller receives a high refrigerant level indication in the evaporator.

Abstract: The invention relates to improvements in compressors and, in particular, to improvements in a method of controlling centrifugal compressors to maximize their efficacy. The compressor has an impeller mounted on a shaft supported by an active magnetic bearing unit and is driven by a variable speed motor at a rotational speed under normal on-load conditions at a calculated pre-surge speed for the required delivery pressure. The actual rotational speed and delivery pressure of the compressor is repeatedly measured and recorded at high frequency. The compressor is allowed to surge periodically after a preset re-calibration time and the compressor is put into a surge recovery cycle when surge is detected, during which the compressor is off-loaded and the rotational speed reduced.

Abstract: The air-conditioning apparatus includes a compressor; a heat source side heat exchanger; a use side pressure-reducing mechanism; a use side heat exchanger and an accumulator connected by a pipe so that a refrigerant circulates therethrough; a high-low pressure bypass pipe; a high-low pressure bypass unit installed in the high-low pressure bypass pipe; and a unit controller configured to perform a refrigerant amount detection operation in which an operation frequency of the compressor is controlled so that a value of an evaporating temperature becomes an evaporating temperature target value of the compressor to discharge a liquid-state refrigerant of the refrigerant from the accumulator, and control an opening degree of the high-low pressure bypass unit in performing the refrigerant amount detection operation.

Abstract: A heat pump-type hot water supply apparatus may be provided that includes: a refrigeration cycle circuit (including a compressor, an outdoor heat exchanger, expansion devices, and an indoor heat exchanger); a hot water supply heat exchanger connected to the refrigeration cycle circuit to use the first refrigerant discharged from the compressor for a hot water supply; a cascade heat exchanger connected to the refrigeration cycle circuit to allow the first refrigerant passing through the hot water supply heat exchanger to evaporate a second refrigerant and thereafter, to be condensed, expanded, and evaporated in the refrigeration cycle circuit; a heat storage compressor compressing the second refrigerant evaporated in the cascade heat exchanger, a heat storage tank to heat water using the second refrigerant compressed by the heat storage compressor, and a heat storage expansion device to expand the second refrigerant condensed in the heat storage tank.

Abstract: A refrigerant cycle device includes a first refrigerant passage for guiding refrigerant from a refrigerant radiator to an inlet side of an outdoor heat exchanger, a first throttle part capable of varying an opening area of the first refrigerant passage, a second refrigerant passage for guiding the refrigerant from the outdoor heat exchanger to a compressor-suction side, a first opening/closing part for opening/closing the second refrigerant passage, a third refrigerant passage for guiding the refrigerant from the outdoor heat exchanger to the compressor-suction side via an evaporator, a second throttle part capable of varying an opening area of the third refrigerant passage, a bypass passage for guiding the refrigerant flowing between the refrigerant radiator and the first throttle part to a position between the outdoor heat exchanger and the second throttle part in the third refrigerant passage, and a second opening/closing part for opening/closing the bypass passage.

Abstract: This invention relates generally to oil lubricated helium compressor units for use in cryogenic refrigeration systems, operating on the Gifford McMahon (GM) cycle. The objective of this invention is to keep the oil separator and absorber, which are components in an oil lubricated, helium compressor, in an indoor air conditioned environment while rejecting at least 65% of the heat from the compressor outdoors during the summer. The balance of the heat is rejected to either the indoor air conditioned air, or cooling water. This is accomplished by circulating hot oil at high pressure to an outdoor air cooled heat exchanger and returning cooled oil to the compressor inlet, while hot high pressure helium is cooled in an air or water cooled heat exchanger in an indoor assembly that includes the compressor, an oil separator, an oil absorber, and other piping and control components. It is an option to reject the heat from the oil to the indoor space during the winter to save on the cost of heating the indoor space.

Abstract: To provide a heat pump apparatus, such as a heat pump water heating apparatus, capable of efficiently supplying high-temperature water by increasing a condensation capacity to a maximum if the outside air temperature is low. The heat pump water heating apparatus is configured to include a first refrigeration cycle and a second refrigeration cycle. The first refrigeration cycle is configured to connect in series a main compressor, a first water-refrigerant heat exchanger, an internal heat exchanger, a first pressure reducing device, and an air heat exchanger. The second refrigeration cycle diverges from the first refrigeration cycle between the first water-refrigerant heat exchanger and the first pressure reducing device, and joins the first refrigeration cycle between the main compressor and the first water-refrigerant heat exchanger.