Abstract: A vapor-compression multi-evaporator cooling system comprises a cooling control system and two or more evaporators each coupled to an expansion valve. Each evaporator is selectively enabled or disabled during operation. When an evaporator is enabled, the evaporator transfers heat into a working fluid within the system. When an evaporator is disabled, the evaporator does not exchange any appreciable amount of heat within the system. The cooling control system includes a cooling controller, an adjustable compressor, a condenser, and a variable speed fan that provides selectable amounts of cooling to the condenser. During operation, the cooling controller adjusts the compressor operation and fan speed to maintain stable operation of the cooling system. To compensate for enabling or disabling of evaporators, the cooling controller adjusts compressor operation and fan speed to provide more or less compression and more or less condenser cooling to maintain stable and efficient operation of the cooling system.

Abstract: An air conditioning apparatus is provided that may include an outdoor unit including a compressor and an outdoor heat exchanger and through which a refrigerant is circulated, an indoor unit through which a fluid, such as water is circulated, and at least one heat exchange device including a heat exchanger in which the refrigerant and the fluid are heat-exchanged with each other.

Abstract: Rotary heat exchangers can include a ride-along compressor, at least a portion of which can be rotated along with the heat exchanger. By rotating at least a portion of the compressor along with the heat exchanger, a sealed fluid circuit containing a two-phase working fluid can be provided. A rotary heat pump or heat engine can include an evaporator and a condenser in the form of back-to-back centrifugal fans. The centrifugal fan blades or other portions of the evaporator and condenser may include internal cavities where the working fluid undergoes a phase change.

Abstract: A heat pump system includes a compressor that compresses and discharges a refrigerant, a decompressor that decompresses the refrigerant, an outdoor unit that exchanges heat between the refrigerant and an outside air, an evaporator that evaporates the refrigerant, a condenser that condenses the refrigerant, an internal heat exchanger, an accumulator that separates the refrigerant into a gas refrigerant and a liquid refrigerant, and a flow pathway changing portion. The internal heat exchanger includes a high-pressure passage through which a high-pressure refrigerant flows, and a low-pressure passage through which a low-pressure refrigerant flows, the internal heat exchanger exchanging heat between the refrigerant flowing through the high-pressure passage and the refrigerant flowing through the low-pressure passage. The flow pathway changing portion that switches between a cooling pathway and a heating pathway. According to this heat pump system, a cooling capacity and a heating capacity can be improved.

Abstract: A refrigeration system, including: a compressor, a condenser, an economizer, a throttle valve, and an evaporator which are connected via a pipeline; and a pneumatic valve that includes a valve body and a drive gas phase refrigerant chamber, an gas phase refrigerant outlet of the economizer being connected to an interstage gas phase refrigerant inlet of the compressor via the valve body, and the drive gas phase refrigerant chamber being connected to a low pressure portion of the refrigeration system via a first gas phase refrigerant path, the lower pressure portion having a pressure lower than that in the economizer; wherein a first valve for controlling on/off of the first gas phase refrigerant path is disposed on the first gas phase refrigerant path. The refrigeration system can avoid liquid phase refrigerant accumulated in the economizer from entering the compressor during start to cause a liquid impact problem.

Abstract: A system and method to analyze building performance without requiring an on-site energy audit or customer input is described. The analysis combines total customer energy load from a power utility with externally-supplied meteorological data to analyze each customer's building performance. Building thermal performance is characterized to produce a rich dataset that the power utility can use in planning and operation, including assessing on-going and forecasted power consumption, and for other purposes, such as providing customers with customized information to inform their energy investment decisions and identifying homes for targeted efficiency funding.

Abstract: Potential energy investment scenarios can be evaluated. Energy performance specifications and prices for both existing and proposed energy-related equipment are selected, from which an initial capital cost is determined. The equipment selections are combined with current fuel consumption data, thermal characteristics of the building, and, as applicable, solar resource and other weather data to create an estimate of the fuel consumption of the proposed equipment. An electricity bill is calculated for the proposed equipment, from which an annual cost is determined. The payback of the proposed energy investment is found by comparing the initial and annual costs.

Abstract: There is disclosed a vehicle air conditioner which is capable of enlarging an effective range of a dehumidifying and heating mode to environmental conditions and smoothly dehumidifying and heating a vehicle interior. A vehicle air conditioner 1 executes a dehumidifying and heating mode in which a controller lets a refrigerant discharged from a compressor 2 radiate heat in a radiator 4, and decompresses the refrigerant by which heat has been radiated and then lets the refrigerant absorb heat in a heat absorber 9 and an outdoor heat exchanger 7, the controller decreases an outdoor blower voltage FANVout of an outdoor blower 15 and decreases an air volume into the outdoor blower 15 in a case where a temperature Te of the heat absorber 9 is high even when the controller adjusts a valve position of an outdoor expansion valve 6 into a lower limit of controlling in a situation in which a temperature TCI of the radiator 4 is satisfactory.

Abstract: A refrigeration apparatus includes a container such as an evaporator for holding refrigerant, and a compressor for compressing refrigerant vapor. The compressed vapor is returned to the container, and stored as liquid. The liquid refrigerant is withdrawn from the container and then returned to the container via a first path through a heat exchanger for cooling a space, or a second path that does not pass through the heat exchanger. Upon returning to the container, the liquid refrigerant is at least partly evaporated due to the reduced pressure in the container caused by the operation of the compressor, and the container is cooled by the latent heat of evaporation. Thus, the container can act as a cold storage unit. The cold storage effect is increased when the refrigerant is returned to the container via the second path.

Abstract: Methods and system for providing de-icing a heat pump heat exchanger and heating a vehicle passenger cabin are presented. In one example, a heat pump that experiences icing of exterior heat exchanger fins may be operated in a cooling mode where a passenger cabin heat exchanger operates as an evaporator to improve de-icing of the exterior heat exchanger fins.

Abstract: A condenser and evaporator system includes (i) a condenser system positioned to receive a gaseous refrigerant from a compressor system and configured to condense the gaseous refrigerant into a liquid refrigerant, (ii) a controlled pressure receiver (CPR) positioned to receive and store the liquid refrigerant, (iii) an evaporator system including a conduit, an expansion valve, and a fan, and (iv) a controller. The conduit is positioned to receive the liquid refrigerant from the CPR. The expansion valve is positioned between the CPR and the conduit, and configured to facilitate modulating an amount of the liquid refrigerant that flows into the conduit from the CPR. The fan is positioned to facilitate providing a cooling operation to an area associated with the evaporator system through evaporation of the liquid refrigerant flowing through the conduit. The controller is configured to control a stage of the condenser system and/or the evaporator system.

Abstract: A heat-pump circuit may include an indoor heat exchanger, an outdoor heat exchanger, a compressor adapted to circulate a working fluid between the indoor and outdoor heat exchangers, and an expansion device disposed between the indoor and outdoor heat exchangers. A monitor for the heat-pump system may include a return-air temperature sensor, a supply-air temperature sensor, and a processor. The return-air temperature sensor may be adapted to measure a first air temperature of air upstream of the indoor heat exchanger. The supply-air temperature sensor may be adapted to measure a second air temperature of air downstream of the indoor heat exchanger. The processor may be in communication with the return-air temperature sensor and the supply-air temperature sensor. The processor may be programmed to determine a working-fluid-charge condition of the heat-pump system based on the first and second air temperatures.

Abstract: A combined heating, ventilation, air conditioning, and refrigeration (“HVACR”) system including an HVAC sub-system and a refrigeration sub-system. The HVAC sub-system is in communication with an open space of an indoor environment and includes a first condenser, a first evaporator, and a first compressor at least partially defining a first refrigerant circuit circulating a first refrigerant for selectively conditioning an airflow within the HVAC subsystem that conditions the open space. The refrigeration sub-system is in communication with an enclosed space within the indoor environment and includes a second condenser, a second evaporator, and a second compressor and at least partially defining a second refrigerant circuit circulating a second refrigerant for selectively conditioning the enclosed space. Heat from the second refrigerant is selectively transferred to the airflow within the second condenser to reheat the airflow prior to the airflow being discharged into the open space.

Abstract: When a first temperature difference is the difference between a saturated gas temperature of a first refrigerant at an inlet side and a saturated liquid temperature of the first refrigerant at an outlet side in a heat exchanger for heating, and when a second temperature difference is the difference between a saturated gas temperature of a second refrigerant at an outlet side and a temperature of the second refrigerant at an inlet side in the heat exchanger for heating, the difference between the first temperature difference and the second temperature difference is held in a predetermined value or less by charging the second refrigerant to the second refrigeration cycle so that a plurality of single refrigerants forming the second refrigerant have a predetermined mixing ratio.

Abstract: An air-conditioning apparatus including a refrigerant circuit having an excess refrigerant recovery pipe connected between an inlet of at least one of heat source side heat exchangers and a first refrigerant flow blocking device or between an outlet of the at least one of the heat source side heat exchangers and a second refrigerant flow blocking device, to a passage connected to a suction side of a compressor, and an excess refrigerant recovery device disposed in the excess refrigerant recovery pipe.

Abstract: A vehicle air conditioner (1A) includes a heat pump circuit (2) including a compressor (11), an outdoor heat exchanger (13), an expansion mechanism (14), a first indoor heat exchanger (15), and a second indoor heat exchanger (16). The flow direction of a refrigerant in the heat pump circuit (2) is switched, by a switching member (12A), between a first direction in which the refrigerant discharged from the compressor (11) passes through the outdoor heat exchanger (13), the expansion mechanism (14), the first indoor heat exchanger (15), and the second indoor heat exchanger (16) in this order and returns to the compressor (11), and a second direction in which the refrigerant discharged from the compressor (11) passes through the first indoor heat exchanger (15), the expansion mechanism (14), the outdoor heat exchanger (13), and the second indoor heat exchanger (16) in this order and returns to the compressor (11).

Abstract: A vehicle heat pump system includes a compressor, a first valve coupled to an outlet of the compressor, a cooling circuit between the first valve and the inlet of the compressor, a heating circuit between the first valve and the inlet of the compressor and a controller. The heating circuit includes a heating circuit evaporator and a second valve between the heating circuit evaporator and the inlet of the compressor. The controller is configured to operate the first valve to switch between a cooling mode and a heating mode, cycle the second valve opened and closed in the heating mode, such that when closed, the compressor draws refrigerant out of the cooling circuit and refrigerant pressure builds up within the heating circuit, and maintain the second valve open upon the controller determining that sufficient refrigerant has been drawn out of the cooling circuit during the cycling of the second valve.

Abstract: A secondary pump-type heat source system includes: heat sources connected in parallel; a load system in which the heat source water flows; a primary pump supplying the heat source water to the load system; a secondary pump provided for each heat source and supplies the heat source water subjected to heat exchange in the load system to the heat source; and a heat source controller calculating flow quantity of the heat source water flowing in the heat source side and flow quantity of the heat source water flowing in the load system side by assigning a result from measurement by a water temperature sensor detecting heat source temperature to an operating characteristic of each heat source and controlling operation of the secondary pumps based on the calculation result.

Abstract: When indoor units are performing a cooling operation, an air-conditioning apparatus controls third flow passage switching valves, for example a first solenoid valve, a second solenoid valve, a third solenoid valve, and a fourth solenoid valve, so that a number of intermediate heat exchangers operating as evaporators is greater than in a cooling main operation. During the cooling main operation, a target value for suction pressure or evaporating temperature at a compressor is set equal to or lower than that in a case in which the indoor units are performing the cooling operation, and a frequency of the compressor and a capacity of a heat-source-side heat exchanger are controlled.

Abstract: A system and process to re-liquefy boil-off liquid natural gas in varied amounts by a process using a screw compressor having an effective compression range from about 10 to about 100 percent of its rated capacity.

Abstract: An air conditioning apparatus includes a refrigerant circuit, first and second shut-off mechanisms, a communication pipe and a refrigerant detection mechanism. The refrigerant circuit is configured to at least perform a cooling operation. The first shut-off mechanism is downstream of the receiver and upstream of the liquid refrigerant connection pipe when the cooling operation is performed. The second shut-off mechanism is downstream of the heat source-side heat exchanger and upstream of the receiver when the cooling operation is performed. The communication pipe interconnects the refrigerant circuit between the first and second shut-off mechanisms, and the refrigerant circuit on the suction side of the compressor. The refrigerant detection mechanism is upstream of the second shut-off mechanism when the cooling operation is performed.

Abstract: A refrigeration cycle apparatus (50) includes: a main refrigerant circuit (21) having a compressor (1), a radiator (2), a first expansion mechanism (5), a second expansion mechanism (6), and an evaporator (4); an injection passage (22) for supplying an intermediate-pressure refrigerant to an injection port 1c of the compressor 1; and a water circuit (30) through which water to be heated in the radiator (2) flows. The refrigeration cycle apparatus (50) includes a sub heat exchanger (3) for cooling the water in the water circuit (30) by exchanging heat between the refrigerant in the injection passage (22) and the water to be heated in the radiator (2).

Abstract: An air conditioner (1) includes a refrigerant circuit (10) configured to perform a supercritical refrigeration cycle and including: an outdoor circuit (21) including a compressor (22), an outdoor heat exchanger (23), and an outdoor expansion valve (24); and two indoor circuits (31a, 31b) including indoor heat exchangers (33a, 33b) and indoor expansion valves (34a, 34b). The air conditioner (1) further includes a controller (50) configured to control outlet refrigerant temperatures of the indoor heat exchangers (33a, 33b).

Abstract: For cooling operation, a refrigeration apparatus includes a heat-source-side valve opening controller for controlling a degree of opening of a heat-source-side expansion valve so that pressure of a refrigerant flowing into the utilization-side expansion valve in the cooling operation becomes equal to or lower than a predetermined reference pressure value. For heating operation, the refrigeration apparatus includes a utilization-side valve opening controller for performing, when a low-quantity utilization unit in which a quantity of the refrigerant falls below a quantity of the refrigerant required for delivering capacity of the utilization unit is found among a plurality of the utilization units in the heating operation, valve opening reducing operation of reducing a degree of opening of the utilization-side expansion valve of the utilization unit except for the low-quantity utilization unit.

Abstract: A refrigeration system includes a refrigerant circuit performing a vapor compression supercritical refrigeration cycle. The system includes a compression mechanism, a heat source heat exchanger, an expander, and a utilization heat exchanger. The expander includes, for two-stage compression, a high pressure side and a low pressure side throttle mechanism, both variable in the amount of throttling. A controller is configured to derive a target value, providing a maximum COP, for the pressure of high pressure refrigerant in the refrigerant circuit based on the temperature of refrigerant at the outlet of either the heat source side heat exchanger or the utilization side heat exchanger, whichever becomes a heat dissipation side heat exchanger functioning as a heat dissipation unit and on the temperature of a medium exchanging heat with refrigerant in the heat dissipation side heat exchanger, at the inlet of the heat dissipation side heat exchanger.

Abstract: A cooling system and method are provided for facilitating two-phase heat transfer from an electronics system including a plurality of electronic devices to be cooled. The cooling system includes a plurality of evaporators coupled to the electronic devices, and a coolant loop for passing system coolant through the evaporators. The coolant loop includes a plurality of coolant branches coupled in parallel, with each coolant branch being coupled in fluid communication with a respective evaporator. The cooling system further includes a control unit for maintaining pressure of system coolant at a system coolant supply side of the coolant branches within a specific pressure range at or above saturation pressure of the system coolant for a given desired saturation temperature of system coolant into the evaporators to facilitate two-phase heat transfer in the plurality of evaporators from the electronic devices to the system coolant at the given desired saturation temperature.

Abstract: In one embodiment, the present invention includes a liquid processing system. In the liquid processing system, a first liquid source transmits feed liquid to a heat exchange unit while a heat generation unit transmits warm coolant to the heat exchange unit. A heat generation unit warms the feed liquid while cooling the warm coolant. The warmed feed liquid is sent to a pump, and cooled feed liquid from a second liquid source is mixed with the warmed feed liquid as necessary until a target temperature is reached. The warmed feed liquid is sent to a reverse osmosis unit for filtering and the resulting permeate is sent to the liquid utilization unit. The cooled coolant is sent from the heat exchange unit to the storage tank and if the cooled coolant is not cool enough, it is sent to a cooling tower for further cooling.

Abstract: A refrigeration device includes a compression mechanism, a radiator, a first expansion mechanism, a liquid receiver, a second expansion mechanism, an evaporator, a pressure detector, a temperature detector, and a control unit. The pressure detector is provided between the refrigerant discharge side of the compression mechanism and the refrigerant inflow side of the first expansion mechanism. The temperature detector is provided between the exit side of the radiator and the refrigerant inflow side of the first expansion mechanism. The control unit controls the first expansion mechanism using the pressure detected by the pressure detector and the temperature detected by the temperature detector so that the refrigerant flowing out from the first expansion mechanism reaches a saturated state.

Abstract: A refrigeration device includes a compression mechanism, a radiator, a first expansion mechanism, a second expansion mechanism, an evaporator, a first internal heat exchanger, a branch pipe a third expansion mechanism, and a second internal heat exchanger. The first internal heat exchanger causes heat to be exchanged between refrigerant that flows from the radiator to the inflow side of the first expansion mechanism, and refrigerant that flows from the evaporator to the compression mechanism. The branch pipe branches from a third refrigerant pipe for connecting the radiator and the second expansion mechanism, and merges with the second refrigerant pipe. A third expansion mechanism is provided to the branch pipe. The second internal heat exchanger causes heat to be exchanged between refrigerant that flows out from the first expansion mechanism, and refrigerant that flows out from the third expansion mechanism.

Abstract: A refrigeration device includes a control unit, and a refrigerant circuit in which a compression mechanism, a radiator, a refrigerant cooling unit, a first expansion mechanism, a liquid receiver, a second expansion mechanism, and an evaporator are connected in sequence. The control unit performs refrigerant cooling control whereby the refrigerant is cooled by the refrigerant cooling unit so that the state of the refrigerant that has flowed out from the first expansion mechanism is near the saturation line and not near the critical point.

Abstract: A vapor compression refrigeration system including components capable of determining the superheat at a compressor inlet is provided. The vapor compression refrigeration system may include sensors capable of making measurements from which the superheat at the compressor inlet may be determined. The vapor compression refrigeration system may be operable to compare the determined superheat level at the inlet to the compressor to a desired superheat level and generate a new evaporator discharge superheat level target for one or more evaporators operatively interconnected to the compressor to affect the superheat at the compressor inlet. The vapor compression refrigeration system may be operable to broadcast the new evaporator discharge superheat level target to the one or more evaporators over a communications bus. The vapor compression refrigeration system may update and broadcast the evaporator discharge superheat level target at programmed intervals.

Abstract: A heat pump type hot water supply outdoor apparatus, in a compressor, a water heat exchanger, a first expansion valve, a medium pressure receiver, a second expansion valve, and an air heat exchanger are connected circularly, has an injection circuit, which is a bypass for a part of the refrigerant between the medium pressure receiver and the second pressure reduction unit, to inject the part of refrigerant into a compression chamber of the compressor, and has a third expansion valve and an internal heat exchanger for carrying out heat exchange between the refrigerant whose pressure is reduced by the third expansion valve and the refrigerant between the medium pressure receiver and the second expansion valve, a pressure detection sensor for detecting a condensing pressure, and a controller for starting an injection control by the third expansion valve at the time when the condensing pressure detected by the pressure sensor or the condensing temperature calculated from the condensing pressure becomes a first pr

Abstract: A first motor-actuated expansion valve and a second motor-actuated expansion valve which are connected in parallel with each other in back-to-back connection are provided between an outdoor heat exchanger and an indoor heat exchanger. In the first motor-actuated expansion valve, at the time of non-operation and full closure, when the refrigerant pressure on the indoor heat exchanger side is higher than the refrigerant pressure on the outdoor heat exchanger side by a predetermined value or more, the full closure is released by receiving the refrigerant pressure on the indoor heat exchanger side. In the second motor-actuated expansion valve, at the time of non-operation and full closure, when the refrigerant pressure on the outdoor heat exchanger side is higher than the refrigerant pressure on the indoor heat exchanger side by a predetermined value or more, the full closure is released by receiving the refrigerant pressure on the outdoor heat exchanger side.

Abstract: A substrate processing apparatus includes: a processing room in which a semiconductor substrate may be treated by a process; a cooling unit positioned to cool the processing room, the cooling unit configured to convey cooling fluid; and a temperature-adjusting unit that alters the temperature of the cooling fluid supplied into the cooling unit. The temperature-adjusting unit has a cycling circuit. The cycling circuit has a compressor configured to compress a refrigerant, a condenser configured to condense the compressed refrigerant, an expander configured to expand the condensed refrigerant, the expander including a plurality of expansion valves arranged in parallel, and an evaporator configured to evaporate the expanded refrigerant, the evaporator positioned to cool the cooling fluid.

Abstract: A climate control system having two or more stages of cooling operation or heating operation is provided for supplying conditioned air to a plurality of zones within a space, where the climate control system comprises a plurality of controllable zone dampers for controlling the supply of conditioned air to each of the plurality of zones, and a plurality of zone temperature sensors for periodically sensing temperature at preset intervals and transmitting sensed temperature information when the temperature of the zone has changed by more than a predetermined amount.

Abstract: A method and apparatus for refrigeration system control includes a control system operable to meet cooling demand and control suction pressure for a plurality of refrigeration circuits each including a variable valve and an expansion valve. The controller controls the variable valve independently of the expansion valves to meet cooling demand by determining a change in a measured parameter and controlling at least one of the variable valves based upon the change to an approximately fully open position.

Abstract: An automobile air conditioning system controls the high pressure of the refrigeration cycle in a wide range of airflows from a low airflow region during an intermediate period to a high airflow region. When a dehumidifying mode is selected, the target high pressure at which the cycle efficiency calculated from a gas cooler outlet refrigerant temperature is maximized is defined as a target value to a valve such as a heating variable throttle valve to control the high pressure of the refrigeration cycle to the target value. This permits control such that the cycle efficiency of the refrigeration cycle is maximized in a wide range of airflow from a low airflow region during an intermediate period to a high airflow region at a relatively low, about 10° C., outside air temperature.

Abstract: A dehumidifying air-conditioning apparatus comprises a pressurizer (4) for raising a pressure of a refrigerant, a condenser (5) for condensing the refrigerant to heat a high-temperature heat source fluid, and an evaporator (1) for evaporating the refrigerant to cool process air to a temperature lower than its dew point. A first heat exchanging portion (21) is disposed in a refrigerant path between the condenser (5) and the evaporator (1) for evaporating the refrigerant under an intermediate pressure between the condensing pressure of the condenser (5) and the evaporating pressure of the evaporator (1) to cool the process air by evaporation of the refrigerant under the intermediate pressure.

Abstract: A heating/air-conditioning installation for a motor vehicle has a thermal loop which includes a refrigerating compressor, a gas cooler, a pressure-reducing valve, an evaporator, and a heating element. The gas cooler and the heating element are grouped together into a single exchanger including a main module forming a main fluid-carrying heat exchanger.

Abstract: By the use of the suction pressure of a compressor, the pressure in back pressure chambers 71g and 71h are reduced to open a refrigerant inlet side and a refrigerant outlet side of an evaporator, and when the compressor is at rest, by the use of a first coil spring 76 and a second coil spring 77, the refrigerant inlet side and the refrigerant outlet side of the evaporator 40 are closed mechanically. Due to this, it is possible to minimize a refrigerant leak by the use of an inexpensive means.

Abstract: A vapor compression refrigeration and freezer system includes a compressor, a condenser, an expansion devise and an evaporator which includes an evaporator coil having an inlet and an outlet which coil is in heat exchange relation with an air medium along substantially the entire coil length. The inlet to the evaporator coil is in flow communication with an outlet of the expansion devise via an evaporator feedline.

Abstract: A vapor compression refrigeration and freezer system includes a compressor, a condenser, an expansion devise and an evaporator which includes an evaporator coil having an inlet and an outlet which coil is in heat exchange relation with an air medium along substantially the entire coil length. The inlet to the evaporator coil is in flow communication with an outlet of the expansion devise via an evaporator feedline.

Abstract: System and method for reducing temperature variation among heat dissipating components in a multi-component computer system. In this respect, component temperatures are controlled to remain relatively constant (approximately within 5° C.) with respect to other components, while allowing for multiple fluctuating heat loads between components. A refrigeration system possessing a variable speed compressor or a constant speed compressor is utilized to control the flow of refrigerant through the refrigeration system. The temperature variation among components is reduced by independently metering the mass flow rate of the refrigerant flowing into each component to compensate for the amount of heat load on each component. In this respect, the mass flow rate of the refrigerant entering into each of the evaporators is metered by valves located upstream from each of the evaporators.

Abstract: A vapor compression refrigeration system includes an evaporator, a compressor, and a condenser interconnected in a closed-loop system. In one embodiment, a multifunctional valve is configured to receive a liquefied heat transfer fluid from the condenser and a hot vapor from the compressor. A saturated vapor line connects the outlet of the multifunctional valve to the inlet of the evaporator and is sized so as to substantially convert the heat transfer fluid exiting the multifunctional valve into a saturated vapor prior to delivery to the evaporator. The multifunctional valve regulates the flow of heat transfer fluid through the valve by monitoring the temperature of the heat transfer fluid returning to the compressor through a suction line coupling the outlet of the evaporator to the inlet of the compressor.

Abstract: An expansion device in a refrigeration chiller defines at least two fixed orifices and employs at least two positionable valve members in order to minimize the overall flow area through the expansion device under a first set of chiller operating conditions, to maximize the overall flow area through the expansion device under a second set of chiller operating conditions and to define a flow area intermediate said minimum and said maximum flow areas when a third set of chiller operating conditions exist.

Abstract: A system for use in regulating the flow of a working fluid, such as a refrigerant, is provided which includes a pressure regulating device. The pressure regulating device controls the mass flow rate of the working fluid in the refrigeration system. The pressure regulating device is controlled based on the saturation characteristics of the working fluid.

Abstract: The present invention consists of a refrigeration unit with an adjusting valve that functions to control the flow of refrigerant and which is installed between the condenser and the evaporator. The adjusting valve is modulated by a controller that adjusts the refrigerant flow from the condenser to the evaporator, depending upon the outflow refrigerant vapor pressure coming from the compressor, condenser, or evaporator. Thus, substantial energy losses are avoided.

Abstract: A refrigerating system, using CO.sub.2 as a refrigerant, for an air conditioner for an automobile. A pressure at the outlet of the heat emitter 2 is controlled to a target value in accordance with the temperature of the refrigerant at the outlet of the heat emitter for obtaining an operation of the refrigerating system along the optimum control line .eta..sub.max. A pressure reducer 4 and a cooler 5 are provided on a branched passageway 28 branched from a refrigerant recirculating passageway 27 for injection. The cooler 5 is for obtaining a heat exchange between a flow of the refrigerant on the branched passageway 28 after being cooled by the pressure reducer and a flow of the refrigerant on the main passageway 27, thereby cooling the refrigerant directed to the evaporator. In a second aspect of the invention, a means is provided for increasing a target value of the pressure at the pressure reducer when a thermal load of the refrigerating system is high.

Abstract: An air conditioner capable of enhancing responsivity of a blowout temperature of conditioned air while preventing occurrence of an overshoot or undershoot condition of the blowout temperature when a user gives an instruction to change the blowout temperature in a dehumidifying operation mode. In a control state, if a set temperature level is adjusted to increase a blowout temperature of conditioned air by increasing the target condenser outlet temperature, the rotating speed of the refrigerant compressor is increased, while the restriction opening of the heating expansion valve is maintained. Thus, the condenser outlet temperature is regulated to the target temperature with minimal undershoot or overshoot of the target temperature.

Abstract: A refrigerant circulation system of the present invention includes a compressor, a condenser, a evaporator, a throttle device and a control unit. The control unit controls a composition of a refrigerant circulating in the refrigerant circulation system based on a temperature and pressure of the refrigerant of an inlet and outlet portion of the compressor, condenser, evaporator and throttle device. The control unit controls to open and close the throttle device to change the composition of the refrigerant circulating in the refrigerant circulation system.