Abstract: The present invention related to cooling systems. More specifically, the present invention relates to a system for cooling one or more parts of a building and or processes comprising a compressor, a condenser having an inlet and an outlet and a plurality of condenser cooling fans, a receiver, a liquid refrigerant pump, an expansion device, an evaporator, the evaporator being surrounded by a chiller barrel having a cooled water return and a chilled water supply line, and refrigerant line means interconnecting the compressor, condenser, expansion device and evaporator in series, in a closed loop for circulating refrigerant therethrough; means for switching the cooling system between free cooling and mechanical cooling and means for actively floating the head pressure in both mechanical and free cooling modes.

Abstract: A refrigerator incorporates an air filter for filtering an airflow passing along at least one refrigeration component into surrounding spaces. The air filter is positioned in an upper machine compartment which houses refrigeration components associated with maintaining temperatures in the refrigerator. At least one sensor is arranged adjacent the air filter to determine a parameter of the air flow. A control, including an air filter analyzer, determines a need for an air filter change based on the sensed parameter. In addition to removing impurities from the airflow, the air filter includes scented media which adds fragrance to the airflow.

Abstract: The present invention related to cooling systems. More specifically, the present invention relates to a system for cooling one or more parts of a building and or processes comprising a compressor, a condenser having an inlet and an outlet and a plurality of condenser cooling fans, a receiver, a liquid refrigerant pump, an expansion device, an evaporator, the evaporator being surrounded by a chiller barrel having a cooled water return and a chilled water supply line, and refrigerant line means interconnecting the compressor, condenser, expansion device and evaporator in series, in a closed loop for circulating refrigerant therethrough; means for switching the cooling system between free cooling and mechanical cooling and means for actively floating the head pressure in both mechanical and free cooling modes.

Abstract: A method of controlling a startup operation in a heat pump water heater system prevents inadvertent shutdowns and/or low operating efficiencies via closed loop control of the system. The method includes choosing an expansion valve opening at startup near an expected steady state value to ensure high system capacity as early as possible, setting a water pump signal to a high level to maximize cycle efficiency during warm-up, and applying closed loop control over the expansion valve and the water pump to increase the pressure in the system in a controlled manner until the system reaches a steady operating state. The method provides stable startup control even if a transcritical vapor compression system is used as the heat pump.

Abstract: A system for monitoring a remote refrigeration system includes a plurality of sensors that monitor parameters of components of the refrigeration system and a communication network that transfers signals generated by each of the plurality of sensors. A management center receives the signals from the communication network and processes the signals to determine an operating condition of at least one of the components. The management center generates an alarm based on the operating condition.

Abstract: A unitary control for operating at least the fan and compressor of a climate control apparatus in response to signals received from a thermostat. The unitary air conditioning control includes a circuit board, a microprocessor on the circuit board, a first relay on the circuit board operable by the microprocessor, to connect a fan connected thereto to line voltage, and having first and second contacts at least one of which is connected to the microprocessor; and a second relay on the circuit board operable by the microprocessor, to connect a compressor connected thereto to line voltage, and having first and second contacts connected to the microprocessor.

Abstract: A container for containing underwater sensors such as sonar transceivers, sonar imaging devices, optical imaging devices, etc, electronic equipment and a cooling liquid for cooling the electronic equipment is connected to a second, variable volume container which acts both as a heat exchanger and as a pressure compensator for compensating the pressure difference between the cooling fluid and the surrounding water or other fluid.

Abstract: A performance enhancement device is disclosed comprising a chimney that is secured to an upward-facing air exhaust of the condenser unit of an air conditioning system for directing the hot air discharged from the condenser away from the air conditioning system. A sun screened enclosure may also be utilized for at least partially surrounding the condenser unit and protecting it from solar radiation. When used in conjunction with the chimney, the chimney extends above the uppermost extent of the sun screened enclosure. One or more misting nozzles may be disposed within the sun screened enclosure for dispersing a water mist within the enclosure. The misting nozzles may be controlled individually, or in groups.

Abstract: An air-conditioning system includes a refrigeration cycle and a control unit. The refrigeration cycle includes an electric compressor in which a compression mechanism for drawing a refrigerant therein for compression is integrated with an electric motor for driving the compression mechanism, and a motor drive circuit for driving the motor is cooled using an intake refrigerant drawn into the compression mechanism. The control unit provides operational control to the motor drive circuit and the refrigeration cycle. When the temperature of the motor drive circuit has exceeded a predetermined temperature, the control unit varies a condition of supplying air to exchange heat with the refrigerant flowing through the refrigeration cycle to thereby reduce the temperature of the intake refrigerant.

Abstract: A refrigerator includes a compressor compressing a refrigerant, a first liquid heat exchanger performing heat exchange between the refrigerant and a first liquid heat medium, an expander expanding the refrigerant, a second liquid heat exchanger performing heat exchange between the refrigerant and a second liquid heat medium, an air heat exchanger performing heat exchange between the refrigerant and air, a blower sending air to the air heat exchanger, a refrigerant flow rate regulator regulating a flow rate of the refrigerant of the first liquid heat exchanger, the second liquid heat exchanger and the air heat exchanger, a pressure sensor detecting a pressure value of the refrigerant of the air heat exchanger, a target pressure value setter setting a target pressure value of the refrigerant of the air heat exchanger in accordance with a target temperature value of the first liquid heat medium, and a blower controller controlling the blower so that the detection value of the pressure sensor becomes the target p

Abstract: A heat transfer system includes a water line for carrying water having a first predetermined flow direction and a refrigerant line for carrying a refrigerant and having a second predetermined flow direction opposite the first predetermined flow direction. The heat transfer system includes a refrigerant evaporator, a vapor compressor, a condenser, and an expansion device. Refrigerant is passed through the refrigerant evaporator as a liquid and is warmed to a cooled gas. The refrigerant is heated to a superheated gas in the vapor compressor, and cooled to a warm liquid in the condenser. The refrigerant is cooled to a bi-phase liquid in the expansion device and is then passed to the refrigerant evaporator. Water enters the refrigerant condenser and heat is exchanged between the refrigerant and the water to warm the water to a predetermined water temperature. The water exits the refrigerant condenser and is passed to the water storage member at a predetermined temperature.

Abstract: The present invention related to cooling systems. More specifically, the present invention relates to a system for cooling one or more parts of a building and or processes comprising a compressor, a condenser having an inlet and an outlet and a plurality of condenser cooling fans, a receiver, a liquid refrigerant pump, an expansion device, an evaporator, the evaporator being surrounded by a chiller barrel having a cooled water return and a chilled water supply line, and refrigerant line means interconnecting the compressor, condenser, expansion device and evaporator in series, in a closed loop for circulating refrigerant therethrough; means for switching the cooling system between free cooling and mechanical cooling and means for actively floating the head pressure in both mechanical and free cooling modes.

Abstract: A method for automatically balancing air conditioning outdoor heat exchange detects a piping measured value of each piping equipment through a detection unit and compares the piping measured value with a set operation mode selected by users and a set value. Airflow amount of adjustable air vents is adjustable according to the comparing result. The method includes the steps of: (1) selecting an operation mode, (2) selecting an effective piping measured value which serves as the basis to operate an air fan device, and (3) based on the piping measured value corresponding to each exchange equipment to open the air vents at a desired degree. By means of the aforesaid method and system, the air conditioning outdoor heat exchange system can be balanced automatically.

Abstract: The invention pertains to a stationary vehicle air conditioning system with a refrigerant circuit, in which at least one compressor circulates the refrigerant to at least two condensers. The at least one compressor may be powered by the vehicle's mechanical power, by an electrical source, or by a combination of these driving forces. Depending on desired operating characteristics, the condensers may be arranged in a series or parallel configuration. A second compressor also may be added, which second compressor may be powered by a source other than the mechanical energy of the vehicle's engine.

Abstract: A method of regulating the refrigerant temperature for a beverage machine, including a refrigeration system for producing a frozen beverage, operating at least one compressor at a speed to flow the refrigerant through the refrigeration system of the beverage machine and cooling the refrigerant with at least one condenser. The method may also include controllably varying the flow of air across the at least one condenser or the speed of the at least one compressor.

Abstract: A method of calculating sensible cooling capacity of a cooling unit includes obtaining compressor capacity, subtracting compressor heat loss from the compressor capacity, subtracting latent cooling capacity from compressor capacity, and subtracting fan power loss from the compressor capacity. Methods of controlling a cooling unit and embodiments of a cooling unit are further disclosed.

Abstract: A controlled flow heat extraction and recovery apparatus using waste heat from a cooling system to heat water to be held in at least one heated water storage tank thereby providing heated water having a purposeful end-use, increasing cooling efficiencies in a cooling system and heating efficiencies in a hot water heating system.

Abstract: A refrigeration unit and diagnostic method therefor are provided. The refrigeration unit includes: a housing with an insulated cavity for storing food and beverages; a vapor cycle system operative to cool the food and beverages in the insulated cavity; a plurality of sensors in communication with the vapor cycle system and outputting data relative to the vapor cycle system; and a controller that, according to the data from the plurality of sensors, determines an occurrence of an event. Wherein the controller logs the data from the plurality of sensors to a data structure according to a first data-logging mode, and logs the data to the data structure according to a second data-logging mode upon occurrence of the event. In one embodiment the refrigeration unit may be a refrigeration line replaceable unit (LRU) configured for an aircraft galley.

Abstract: The invention pertains to a stationary vehicle air conditioning system with a refrigerant circuit, in which a compressor circulates refrigerant through a refrigerant circuit including at least one condenser. The one compressor may be powered by the vehicle's mechanical power, by an electrical source, or by a combination of these driving forces. Depending on desired operating characteristics, a plurality of condensers may be arranged in a series or parallel configuration within the circuit, and a second compressor also may be added, which second compressor may be powered by a source other than the mechanical energy of the vehicle's engine. A plurality of fans may be positioned and selectively operable to provide cooling air streams to one or more of the condensers, with the vehicle engine mechanically driving one fan and an electrical power source driving another fan.

Abstract: A system includes a plurality of distributed refrigeration units respectively coupled to discrete refrigeration circuits. Each refrigeration unit may include a variable compressor, a fixed compressor, a condensing unit, and a controller. The controller compares an operating condition of the refrigeration unit to a refrigeration circuit set point to select a compressor staging capable of achieving the refrigeration circuit set point.

Abstract: A vapor generating and recovery apparatus including a housing having an open top, a closed bottom and a plurality of sidewalls therebetween defining a boiling sump with a treating solution therein. The housing is further provided with at least one heating coil and at least one condensing coil for providing and removing heat from the apparatus. The housing also includes at least one glove extending through one of the sidewalls allowing a user to manually handle and/or manually spray parts or objects needing cleaning using the vapor generating and recovery apparatus.

Abstract: A method and system for controlling a cooling fan that cooperates with an air conditioning condenser in a vehicle. The present embodiments include steps and corresponding implementations for determining a speed of the vehicle, determining a discharge pressure of the air conditioning condenser, determining an ambient temperature of air surrounding the vehicle and determining an outlet temperature of a vehicle air conditioning system. The cooling fan is operated in one or more desired fan speed modes corresponding to one or more respective discharge pressure ranges. The fan speed modes are a function of vehicle speed and one or more of ambient temperature, outlet temperature, and discharge pressure.

Abstract: The present invention provides a solid polymer electrolyte fuel cell comprising a fuel cell stack 21 formed by laminating a plurality of fuel cell units each of which includes a fuel electrode 23, an oxidant electrode 24, and a solid polymer electrolyte membrane 22 interposed between the fuel and oxidant electrodes. The fuel cell unit is operable to generate an electric power through an electrochemical reaction between a first gas supplied to the side of the fuel electrode 23 and a second gas supplied to the side of the oxidant electrode 24. In this fuel cell, the first gas supplied to the side of the fuel electrode 23 and the second gas supplied to the side of the oxidant electrode 24 are adapted to flow generally in opposite directions in the fuel cell stack 21, so that a water created on the side of oxidant electrode 24 is reciprocally moved between the fuel electrode 23 and the oxidant electrode 24 to increase a water holding region in the solid polymer electrolyte membrane 22.

Abstract: In a refrigeration cycle device in which heat generated by heat absorption of an evaporator is used for heating in a condenser, a disadvantage that a cooling capacity of the evaporator deteriorates owing to shortage or drop of an amount of the heat to be rejected from the condenser is securely avoided and a cooling function is maintained. In the refrigeration cycle device which is provided with a refrigerant circuit including a compressor, a condenser, an expansion valve and an evaporator and which exhibits a heating function by the heat rejected from the condenser and which exhibits the cooling function by the heat absorption of the evaporator, an operation to secure a predetermined amount of the heat to be rejected from the condenser is executed in order to maintain the cooling function of the evaporator based on an index capable of grasping the amount of the heat to be rejected from the condenser.

Abstract: A controller comprises a first input that receives a signal indicating an energy consumption value of a compressor, a second input that receives a signal indicating an energy consumption value of a variable speed condenser fan, and an output that provides a control signal to the variable speed condenser fan. The controller also comprises a memory that stores a condenser set point, and a processor in communication with the input, output and memory and that modulates the condenser set-point to minimize energy consumption and controls the variable speed condenser fan based on the condenser set-point.

Abstract: Provided are an outdoor unit of an air conditioner, and an operation method thereof. The outdoor unit of the air conditioner includes: a case including an outlet; and an outlet door installed at the case to open/close the outlet, and guiding the air being discharged when opened. Thus, the air being discharge can be guided in a desired direction when the outlet is opened, and foreign substances can be prevented from flowing into the case when the outlet is closed.

Abstract: An energy-efficient heat pump water heating system determines whether to energize a heat pump by interpreting readings from one or temperature sensors based on two thresholds. The heat pump is energized if the detected temperature falls below a first threshold and de-energized when the detected temperature rises above a second threshold. The thresholds may correspond to outputs of two or more sensors. Using multiple temperature thresholds improves the temperature sensing capabilities of the system, thereby improving energy efficiency by matching heat pump operation with hot water demand more closely than previously known systems.

Abstract: Refrigerant is circulated through a vapor compression system including a compressor, a gas cooler, an expansion device, and an evaporator. An auxiliary electric heater is activated to further heat the heated water exiting the gas cooler when the heating capacity of the system is low. The auxiliary electric heater can be located on the water line exiting the gas cooler, in a water tank that stores the heated water, or on the refrigerant line proximate to the compressor discharge.

Abstract: Cooling plant for a “cooled” fluid, able to cool and/or dry the fluid by means of cooling substantially to a pre-established temperature, the plant comprising a heat exchanger (17), to cool the fluid, by means of heat exchange with a “cooling” fluid inserted in a cooling unit (11) comprising a cooling circuit (13) able to feed the cooling fluid to the heat exchanger (17), the cooling unit (11) comprising at least a condensation device (15), able to take the cooling fluid to within desired parameters of pressure and/or temperature. The plant also comprises regulation means (19) able to detect the temperature of the fluid to be controlled, and to act on the condensation device (15) in order to vary the parameters of pressure and/or temperature of the cooling fluid.

Abstract: This invention relates to a rotational speed control system including a plurality of motor drivers for driving motors, and the object thereof is to drive a plurality of motors at the same rotational speed without depending on the number of motor drivers and without depending on the characteristics of each motor driver. A remote controller 31 and a motor driver 202 are connected to a motor driver 201. The motor drivers 201 and 202 control motors M11 and M12 at a prescribed rotational speed, respectively. A rotational speed instructing signal 91 indicative of the rotational speed is supplied from the remote controller 31 to the motor driver 201, and further supplied from the motor driver 201 to the motor driver 202. Because the rotational speed instructing signal 91 indicates a rotational speed which is transmitted in a digital value between the motor drivers 201 and 202, both of the motors M11 and M12 are driven at the rotational speed indicated by the rotational speed instructing signal 91.

Abstract: Cooling control device for a condenser is provided which includes the condenser, a cooling device for cooling the condenser, and a control device for controlling the cooling device. The cooling device includes a first cooling fan for cooling a gaseous-phase portion of the condenser, and two second cooling fans for cooling a liquid-phase portion of the condenser independently of the first cooling fan. The control device also includes a pressure control section for optimally adjusting a pressure within the gaseous-phase portion, and a temperature control section for optimally adjusting a temperature within the liquid-phase portion. The pressure control section operates the first cooling fan, in accordance with a detected pressure within the gaseous-phase portion, to adjust the pressure within the gaseous-phase portion.

Abstract: A method of controlling a startup operation in a heat pump water heater system prevents inadvertent shutdowns and/or low operating efficiencies via closed loop control of the system. The method includes choosing an expansion valve opening at startup near an expected steady state value to ensure high system capacity as early as possible, setting a water pump signal to a high level to maximize cycle efficiency during warm-up, and applying closed loop control over the expansion valve and the water pump to increase the pressure in the system in a controlled manner until the system reaches a steady operating state. The method provides stable startup control even if a transcritical vapor compression system is used as the heat pump.

Abstract: In a liquid-level-position control device for a condenser in a Rankine cycle apparatus, first and second reference liquid level positions are set. When a position of the fluid level is lower than the first reference liquid level position, water is replenished to a condenser by a liquid-phase working medium supply section. When the position of the fluid level is higher than the second reference liquid level position, the liquid-phase working medium is discharged from within the condenser by a liquid-phase working medium discharge section. In this way, the liquid level, which is a boundary surface between water vapor and condensed water within the condenser, can be constantly kept at an optimal position.

Abstract: A driving load of a cooling fan unit is selectively determined from a plurality of predetermined loads corresponding to vehicle parameters including a coolant temperature and a vehicle speed. Also, on the basis of a plurality of coolant temperature ranges and a plurality of vehicle speed ranges. The cooling fan unit is driven with the determined driving load. The vehicle parameters preferably further include a refrigerant pressure and a state of an air/con switch.

Abstract: A system and method for cooling air includes using a refrigerant cooling system and further using a refrigerant liquefaction subsystem or method that includes using a heat sink cooler (“pre-cooler”) to cool the heat sink coolant before it is used to cool the refrigerant in the condenser. One aspect of the refrigerant liquefaction subsystem may use a water mist, which may be prepared by atomizers, high pressure nozzles, piezo-electric ultrasonic nebulizers, or the like, to cool the heat sink coolant.

Abstract: The invention proposes an air conditioning installation furnished with an injection computer (42), with an air conditioning apparatus and with an electronic control device (401). The installation furthermore comprises measurement facilities making it possible to establish values relating to the temperature of the external air stream at the inlet of the condenser, to the pressure at the outlet of the compressor (123), and to the pressure at the inlet of the compressor (122). The electronic control device (401) implements the solving of a linear equation, relating the mass flow rate of the refrigerant to the values measured by the measurement facilities so as to calculate an estimate of a quantity relating to the refrigerant. On the basis of this quantity, the electronic device can estimate the power absorbed by the compressor (14).

Abstract: An apparatus and method for controlling louver blades of a compressor/condenser unit are provided which can improve efficiency of the compressor/condenser unit based on a position of the louver blades and peripheral conditions. The apparatus includes louver blades with a pair of connecting protrusions formed at each end thereof, and a plurality of levers which are rotatably coupled to the connecting protrusions of the louver blades formed in the same positions. A driving member opens and closes the louver blades by moving the levers, and in turn, the louver blades coupled there to. A microcomputer controls the driving member, and the louver blades are opened and closed based on a control signal from the microcomputer.

Abstract: A heat rejection apparatus includes an object conducting heat to be rejected, with an absorptive material on the outside of the object. A water system deposits water on the absorptive material to wet the material to absorb heat from the object by water evaporation. A collector below the object directs excess water to a drain. An air delivery system directs air over the absorptive material on the object. The water system supplies enough water to keep the absorptive material wet, even with the evaporative losses of water, and carry dissolved solids to the collector.

Abstract: The present invention relates to systems and methods for controlling head pressure in a vapor compression system, e.g. in a precision air conditioning system. One embodiment of the invention provides a method for regulating working fluid flow in a vapor compression system including a compressor. The method includes: providing a controller; receiving signals at the controller representative of a monitored discharge pressure in a discharge line of the compressor; and using the controller to provide a control signal to an actuator that controls a flow control valve that, in turn, controls working fluid flow into the system, the control signal being responsive at least in part to a difference between a set point pressure and the monitored discharge pressure.

Abstract: The present invention discloses an apparatus and method for controlling an operation of an outdoor unit which can efficiently control the outdoor unit by mounting sensors on the outdoor unit. The apparatus for controlling the operation of the outdoor unit includes: a pressure sensor for sensing a pressure of refrigerants in an outlet of a compressor of the outdoor unit; a temperature sensor for sensing a temperature of the refrigerants in an outlet of a condenser; and a microcomputer for comparing the pressure from the pressure sensor and the temperature from the temperature sensor with optimal pressure and temperature ranges, and controlling operation conditions of at least a blast fan and the compressor in the outdoor unit to be inversely proportional to each other according to the comparison results.

Abstract: A vehicle air conditioning control apparatus having an externally controlled type compressor 3 and an externally controlled type cooling electric fan 9 is disclosed in which a control map, for determining a duty ratio for a fan motor 10 in terms of a compressor discharge pressure Pd, is determined based on the maximum efficiency point, for providing the maximum fuel consumption, that allows a total engine load torque, represented by a total sum of an engine load torque caused by the externally controlled type compressor 3 and an engine load torque caused by a fan motor 10, to be a minimum torque, and a duty voltage to be applied to the fan motor 10 is controlled using the compressor outlet pressure Pd and the control map which is determined.

Abstract: An apparatus is described for applying a fine mist of water to an air conditioner condenser coil for increasing the heat transfer thereof. A water source under normal utility pressure is tapped for flow into a reduced diameter tube supplying the apparatus. Said tube water is filtered and electrolysis protected by a magnesium element affixed to the tube and to the air conditioner structure. A metering valve used exclusively for metering small flows of liquid Freon-type refrigerant, is modified and adapted for exclusive use in metering water to the misters. It is conjoined with a temperature sensor bulb filled with expandable refrigerator coolant as a control initiator and which communicates with said valve via a sealed capillary tube to a chamber and diaphragm means. As the sensor bulb is located at the heat exchanger coil, this expansion valve meters water flow control in accordance with the temperature of the heat exchanger, without the use of electricity or dependence on fan power.

Abstract: A transcritical refrigeration system includes a compressor, a gas cooler, an expansion device, and an evaporator. Refrigerant is circulated though the closed circuit system. Preferably, carbon dioxide is used as the refrigerant. A fan moves outdoor air that exchanges heat with the refrigerant across the evaporator. The speed of the fan is regulated to regulate the evaporator pressure and to adapt the evaporator to different environmental conditions to achieve the optimal coefficient of performance. During high ambient conditions, the fan speed is decreased, decreasing the refrigerant mass flowrate in the system. The energy exchange per unit mass of the refrigerant in the gas cooler increases and the work of the fan decreases, increasing the coefficient of performance of the system. During low ambient conditions, the mass flowrate of the system is low and there is more heat transfer thermal resistance on the refrigerant side at the evaporator. The speed of the fan is lowered to decrease the work of the fan.

Abstract: A system and method for cooling air includes using a refrigerant cooling system and further using a refrigerant liquefaction subsystem or method that includes using a heat sink cooler (“pre-cooler”) to cool the heat sink coolant before it is used to cool the refrigerant in the condenser. One aspect of the refrigerant liquefaction subsystem may use a water mist, which may be prepared by atomizers, high pressure nozzles, piezo-electric ultrasonic nebulizers, or the like, to cool the heat sink coolant.

Abstract: The present invention discloses an apparatus and method for controlling louver blades of an outdoor unit which can improve efficiency of the outdoor unit according to a state of the louver blades and peripheral conditions. The apparatus for controlling the louver blades of the outdoor unit includes: a louver blade member including louver blades having a pair of connecting protrusions at their both ends, and first to fourth levers for rotatably connecting the connecting protrusions of the louver blades formed in the same positions; a driving member for opening/closing the louver blades by moving the first to fourth levers in the vertical direction to the louver blades by a predetermined distance; and a microcomputer for controlling the driving member, and opening/closing the louver blades by generating a control command.

Abstract: A temperature conditioning system includes a damper system that determines the pattern of airflow through two coil slabs of an indoor heat exchanger, wherein the heat exchanger is preferably part of a split-system air conditioner or a heat pump. In a normal mode position, the damper system directs the airflow in a parallel flow relationship through the two coil slabs for optimum capacity and efficiency. In an enhanced mode position, the damper system directs the airflow in a series flow relationship through the two coil slabs. The enhanced mode position not only helps reduce humidity when the temperature conditioning system operates in a cooling mode but also helps raise the supply air temperature at a room register when the system is operating in a heating mode. In some embodiments, the damper system is also movable to a bypass position that allows the air to bypass the indoor heat exchanger.

Abstract: A control device for a motor fan of a vehicle, which controls the motor fan to cool a radiator for engine coolant and a condenser for air conditioner refrigerant, includes: a first command value calculation section which calculates a first command value for control of the motor fan according to refrigerant pressure; a second command value calculation section which calculates a second command value for control of the motor fan according to coolant temperature; a first target value setting section which sets the greater of the first command value and the second command value as a first target value; a second target value setting section which obtains a second target value for control of the motor fan which corresponds to a total torque which is smaller than a total torque of a torque of an alternator and a torque of a compressor corresponding to the first target value; and a control section which controls the motor fan according to the second target value.

Abstract: A chiller plant which produces chilled water for airconditioning, or an industrial process and which is comprised of chillers, cooling fluid pumps, and cooling towers with electrical motor drives uses a substantial amount of energy. A method that coordinates the operation of the cooling tower, cooling fluid pumps, and refrigeration machines so that the chiller plant operates at a higher overall efficiency thus reducing the power usage has been developed and is presented herein. The flow rate of the cooling fluid pumps are controlled to maintain a precise temperature difference across the refrigerant condenser. The cooling tower fans are controlled by comparing the cooling fluid temperature and the cooling fluid flow rate to selected design parameters. The heat rejection rate is measured for each chiller in the chiller plant and operating set points are established for each operating chiller to provide the optimum operation for best energy efficiency.

Abstract: Disclosed is a cooling-heating combination air conditioner being provided with an outdoor heat exchanger and an indoor heat exchanger in a single case. The present invention has advantages of freely adjusting a ventilation rate from 0% to 100% with its simple structure without equipping a separate ventilator, and improving efficiency in cooling and heating effectively by recovering an air discharged during a ventilation process and a waste energy of condensed water generated in the indoor heat exchanger and by maximizing a path along which a coolant is circulated according to cooling-heating mode conversion.

Abstract: A control device for a motor fan of a vehicle, which controls the motor fan to cool a radiator for engine coolant and a condenser for air conditioner refrigerant, includes: a first command value calculation section which calculates a first command value for control of the motor fan according to refrigerant pressure; a second command value calculation section which calculates a second command value for control of the motor fan according to coolant temperature; a first target value setting section which sets the greater of the first command value and the second command value as a first target value; a second target value setting section which obtains a second target value for control of the motor fan which corresponds to a total torque which is smaller than a total torque of a torque of an alternator and a torque of a compressor corresponding to the first target value; and a control section which controls the motor fan according to the second target value.