Abstract: Disclosed are an air conditioning system with two compressors and a method for operating the same, so as to variably change a compression capacity of a refrigerant according to the variation of cooling load. Herein, when a full operation order is inputted to the two compressors in order to satisfy increased cooling load, the first compressor is first operated, and then the second compressor having a compression capacity of a refrigerant smaller than that of the first compressor is additionally operated, so that a current peak value for operating the compressors does not exceed an allowable current range of a circuit breaker installed in a home or building, thereby safely controlling the air conditioning system and simultaneously allowing the current to be provided to other electric appliances, thus improving users' convenience.

Abstract: A system and method of providing floating actuator control is provided. This system and method receives input command signals from an actuator controller, and effectively integrates these signals until the controller has requested a large enough movement of the actuator that the actuator can actually effectuate. At this point, the system and method drive the actuator to the commanded position. As a result, excessive mechanical wear in the actuator caused by small command signal perturbations and dither is reduced or eliminated.

Abstract: An apparatus and method for drying condensate from the heat exchanger of a vehicle's air conditioning system after operation in order to thwart odor buildup is provided. The apparatus and method operate regardless of whether the system's blower control circuit is positively or negatively switched. The apparatus includes relays that bypass the normal operating electrical routing to the air conditioning system's blower motor to operate the blower directly. The method comprises determining that the engine of the vehicle has been switched off and that the air conditioning system of the vehicle was in operation prior to the engine being switched off. If the conditions are met, the air conditioning system's blower is operated on a predetermined time schedule to circulate air in the air conditioning system to dry condensate therefrom. In this way, growth of odor-causing fungus and bacteria is inhibited.

Abstract: A first solenoid-operated, discharge-line control valve (26) is moved between open and closed positions to control fluid flow in the discharge fluid line (18) between the compressor (12) and the condenser (14). A second solenoid-operated, liquid-line control valve (28) is moved between open and closed positions to control fluid flow in the liquid fluid line (20) between the condenser (14) and the evaporator (16). A controller (36) closes one of the flow control valves (26, 28) a period of time before closing the other flow control valve (26, 28) and shuts down the compressor (12) sequentially with the flow control valves (26, 28).

Abstract: An air conditioning system and a method for operating the air conditioning system, in which a plurality of compressors are simultaneously or selectively operated, based on the difference between a room temperature and a desired temperature generated during a waiting time for re-operation of the compressors. The room temperature varying during the waiting time for the re-operation of the compressors maintained at a stopped state is sensed to determine whether or not an increase in cooling load occurs. Based on the amount of the cooling load, it is determined whether the compressors have to operate simultaneously or selectively. That is, the refrigerant compression capacity of the air conditioning system is determined by reflecting the cooling load caused by a variation in room temperature occurring during the waiting time for re-operation taken until any compressor maintained in a stopped state is re-operated.

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: A refrigerator includes a housing that encloses at least one interior space, a low temperature generator or refrigerating machine for cooling the interior space, and a control device for receiving a target signal and for controlling the temperature of the interior space to a target temperature represented by the target signal, by controlling the operation of the refrigerating machine. A control element supplies the target signal to the control device with a level that varies in accordance with a predetermined course.

Abstract: In a seat air conditioning unit for a vehicle seat constructed with a seat cushion and a seat back, when a seat air conditioning operation is performed in a cooling operation of a passenger compartment, a cooling capacity of cool air blown from the seat back is set smaller than a cooling capacity of cool air blown from these at cushion while a passenger sits on the vehicle seat. Further, the cooling capacity of cool air blown from a lower portion of the seat back can be set smaller than the cooling capacity of an upper portion of the seat back. Accordingly, even when the cooling operation is continued for a long time while the seat air conditioning operation is performed, the waist portion of the passenger can be prevented from being excessively cooled.

Abstract: A freezing prevention system for a refrigeration device includes a freezing-prevention temperature sensor for detecting a refrigerant temperature in a refrigerant evaporator, and a control unit for controlling operation of a refrigerant compressor based on the detected refrigerant temperature. The control unit includes a calculating means for calculating an integral value of the detected refrigerant temperature integrating with respect to a passed time after the detected refrigerant temperature becomes equal to or lower than 0° C. When the integral value becomes equal to or larger than a predetermined value, the control unit stops the operation of the refrigerant compressor. Accordingly, the freezing prevention system can accurately perform a freezing prevention control while its production cost can be reduced.

Abstract: A method for controlling cycling of an air conditioning compressor coupled to an internal combustion engine interrupts normal cycling based on operation conditions. In addition, normal engaged and disengaged cycling durations are adaptively estimated in real-time. The method of the present invention achieves improved fuel economy and improved drive feel. As an example, improved fuel economy is achieved by engaging the compressor during braking or when the engine is being driven by the vehicle. As another example, improved drive feel is achieved by engaging the compressor during transient conditions when drive feel is unaffected.

Abstract: Control apparatus for an environmental control system comprises input circuitry receiving environmental information and output circuitry for controlling an HVAC system. Processing circuitry in the controller configures the output circuitry based at least in part on the signals received on the input circuitry. Information about the status of the HVAC system may be transferred to system administrators using a wireless link.

Abstract: An air conditioner for vehicle has a refrigeration cycle with a variable displacement type compressor. A fuel cut control is carried out in response to a vehicle deceleration. In the fuel cut control, the displacement is first increased so that an evaporator performs as a cold storage. Then, if an engine speed is decreased to a certain level, the displacement is decreased to decrease an engine load. The displacement is kept in the decreased level for a predetermined time period or until the end of the fuel cut control. Even when the displacement is decreased, the evaporator can cool air, since the evaporator performs as the cold storage. Further, the time period for keeping the displacement in the decreased level is limited. Therefore, it is possible to prevent an excessive temperature rise and to keep comfortable air conditioning.

Abstract: Disclosed are compressor-controlling device and method for an air conditioner comprising a plurality of compressors. The compressor-controlling device comprises a movable timer for sensing a stopping time (t) of stopped compressors selected from the plural compressors according to a decrease of a cooling load, a comparison unit for determining whether the stopping time (t) sensed by the movable timer exceeds a designated time (T), and a control unit for re-operating the stopped compressors after a lapse of the designated time (T) when the cooling load is increased, in case the comparison unit judges that the stopping time (t) does not exceed the designated time (T). When the cooling load is increased, the stopped compressors for satisfying the decrease of a cooling load are re-operated after the lapse of the designated time. Therefore, the compressor-controlling device assures the reliability of its system.

Abstract: A device and method for automatically defrosting a refrigeration system only during times of non-peak energy demand. The device is a defrost delay module that plugs into the current defrost timer supplied with frost-free refrigerators. The defrost delay module includes a microprocessor that utilizes a clock to define peak power consumption periods. If the defrost cycle will occur during a peak power period, the delay module interrupts the normal operation and prevents defrosting of a refrigerator or freezer until the peak power periods has passed. The delay module is able to learn the operating characteristics of the defrost timer such that the delay module can be retrofit to existing appliances.

Abstract: Disclosed are compressor-controlling device and method for an air conditioner comprising a plurality of compressors. The compressor-controlling device comprises a movable timer for sensing a stopping time (t) of stopped compressors selected from the plural compressors according to a decrease of a cooling load, a comparison unit for determining whether the stopping time (t) sensed by the movable timer exceeds a designated time (T), and a control unit for re-operating the stopped compressors after a lapse of the designated time (T) when the cooling load is increased, in case the comparison unit judges that the stopping time (t) does not exceed the designated time (T). When the cooling load is increased, the stopped compressors for satisfying the decrease of a cooling load are re-operated after the lapse of the designated time. Therefore, the compressor-controlling device assures the reliability of its system.

Abstract: A first solenoid-operated, discharge-line control valve (26) is moved between open and closed positions to control fluid flow in the discharge fluid line (18) between the compressor (12) and the condenser (14). A second solenoid-operated, liquid-line control valve (28) is moved between open and closed positions to control fluid flow in the liquid fluid line (20) between the condenser (14) and the evaporator (16). A controller (36) closes one of the flow control valves (26, 28) a period of time before closing the other flow control valve (26, 28) and shuts down the compressor (12) sequentially with the flow control valves (26, 28).

Abstract: A fluid fill system includes at least one sensor for indicating whether a fluid level in a reservoir is equal to or greater than a predetermined fluid level and a process control. The process control obtains a reading from the at least one sensor at a predetermined interval and increments a counter if the reading indicates that the fluid level is equal to or greater than the predetermined fluid level and decrements the counter if the reading indicates that the fluid level is less than the predetermined fluid level. Process control operates a fluid supply mechanism when a value of the counter moves beyond a predetermined value.

Abstract: An air conditioning system and a method for operating the air conditioning system, in which a plurality of compressors are simultaneously or selectively operated, based on the difference between a room temperature and a desired temperature generated during a waiting time for re-operation of the compressors. The room temperature varying during the waiting time for the re-operation of the compressors maintained at a stopped state is sensed to determine whether or not an increase in cooling load occurs. Based on the amount of the cooling load, it is determined whether the compressors have to operate simultaneously or selectively. That is, the refrigerant compression capacity of the air conditioning system is determined by reflecting the cooling load caused by a variation in room temperature occurring during the waiting time for re-operation taken until any compressor maintained in a stopped state is re-operated.

Abstract: An apparatus and method for drying condensate from the heat exchanger of a vehicle's air conditioning system after operation in order to thwart odor buildup is provided. The apparatus and method operate regardless of whether the system's blower control circuit is positively or negatively switched. The apparatus includes relays that bypass the normal operating electrical routing to the air conditioning system's blower motor to operate the blower directly. The method comprises determining that the engine of the vehicle has been switched off and that the air conditioning system of the vehicle was in operation prior to the engine being switched off. If the conditions are met, the air conditioning system's blower is operated on a predetermined time schedule to circulate air in the air conditioning system to dry condensate therefrom. In this way, growth of odor-causing fungus and bacteria is inhibited.

Abstract: A refrigeration system for cooling a logic module includes an evaporator housing including an evaporator block in thermal communication with the logic module. The evaporator housing includes a humidity sensor for detecting a humidity within the evaporator housing. The system further comprises a controller for controlling a refrigeration unit supplying cold refrigerant to the evaporator block in response to the operating conditions of the logic module and the temperature of the evaporator block. In another aspect of the invention, two modular refrigeration units are independently operable to cool the evaporator block, and each refrigeration unit is controllable in various modes of operation including an enabled mode in which it is ready to cool the evaporator and an on mode in which it is actively cooling the evaporator. In another aspect of the invention, the evaporator block and a heater on a reverse side of the circuit board are particularly controlled during concurrent repair operations.

Abstract: A control apparatus that promptly increases the displacement of a compressor after the compressor is started while liquefied refrigerant is lingering in an external circuit. The control apparatus includes a restricting passage. The restricting passage is located in a first pressure introduction passage, through which the pressure of the first pressure monitoring point flows to the control valve. The restricting passage decreases the pressure of refrigerant that flows through the passage. When the compressor is started while liquefied refrigerant is lingering in the external circuit and the pressure of the first pressure monitoring point is abruptly increased, the restricting passage reduces the increase of the pressure that is detected by the control valve. Therefore, the displacement of the compressor is promptly increased.

Abstract: A method and apparatus for cooling an air conditioning system's condensing coils utilizing air filter pad made of glass fibers with self contained, perforated water capillary tubes allowing moisture to permeate the filter pad. The filter dads are connectable in series and provided with integral mounting strips for fixed or magnetic, internal or external attachment to the condensing unit. Special adaptive solenoids are also provided to allow for minimum flow of water over long periods of time. Dual sensors are provided connected to both the high and low side of the compressor for sensing compressor temperature status and switching the solenoid on and off, thereby preventing freezing. A unique method for applying chilled water to the capillary tubes by coiling the capillary tube around the suction line of the compressor is utilized.

Abstract: A dehumification/refrigeration system has a first suction stop valve, first evaporator and first timer control contact and a second suction stop valve, second evaporator and second timer control contact. The first suction stop valve is adapted to inactivate the first evaporator upon the detection of ice and to activate the second suction stop valve and second evaporator. The second suction stop valve is adapted to inactivate the second evaporator upon the detection of ice and to activate the first suction stop valve and first evaporator. A supplemental relay and an associated third timer control contact simultaneously activate the first timer and second control contacts. A timer sequentially activates one timer control contact to the exclusion of the others.

Abstract: Disclosed is a method for controlling operation of a kimchi storage device. A compressor operates immediately if the condition to operate the compressor is met, and a heater operates after a predetermined time delay if the condition to operate the heater has been met, whereby the variation in the temperature of a storage chamber caused by the immediate sensing of low temperature and the operation of the heater thereby can be reduced, so the flavor and freshness of the kimchi can be enhanced.

Abstract: A method for estimating the duration of the interruptions in the supply from the electric mains in an electric appliance having an electronic control, in particular a household appliance, includes the steps of (a) on the occasion of an interruption of the supply voltage of the apparatus, measuring and storing the value of at least one quantity that is characteristic of the operating status of the apparatus; (b) on the occasion of the restoration of the supply voltage, measuring the current value of the at least one characteristic quantity; (c) comparing the stored value and the current value of the at least one characteristic quantity; and (d) estimating, on the basis of the comparison, the duration of the interruption of the supply voltage.

Abstract: A method and device (18) to control the temperature T in a refrigerator or freezer cabinet (10), which keep a set temperature in a space (12) in the cabinet. The space is refrigerated by an element (14) of an intermittently operating refrigerating machine (16). The refrigerator cabinet has a control gear (18), which consists of a first means (20) and a second means (22), a third means (24) and a fourth means (26). The first means is situated at the refrigerating element, which is placed in the space, and it measures a regulating temperature. The second means is arranged at a reference point in the space, and it measures a current temperature in the space. The third means compiles an average temperature of the current temperatures. The forth means compiles a discrepancy between the average temperature and a preset temperature.

Abstract: A floodback detector for refrigerant systems employing any of: minimum suction temperature, temperature rate of change and duration thereof; minimum superheat, superheat rate of change and duration thereof.

Abstract: A displacement control device comprises a control valve. The control valve controls the pressure in a crank chamber. The control valve includes a valve body, and an electromagnetic actuator. A power source supplies the current to the actuator. A switch device located between the actuator and the power source. A controller determines a target value of the current supplied to the actuator in accordance with an external condition. When the target value is changed to a new value, the controller controls the switching of the switch device such that the current is intermittently supplied from the power source to the actuator before the current is set to the new target value. This permits the displacement of the compressor to be smoothly and rapidly changed.

Abstract: A capacity control device controls a discharge capacity of a variable displacement compressor for use in an automotive air conditioning system. The air conditioning system has the compressor and an evaporator fan. The device includes a control, a first detector, and a second detector. The control changes the discharge capacity of the compressor between a minimum discharge capacity for that compressor and a maximum discharge capacity. The first detector detects an elapsed time of a minimum discharge capacity operation of the compressor. The second detector detects an impressed voltage of the evaporator fan of the air conditioning system. The discharge capacity increases from the minimum discharge capacity to a predetermined discharge capacity when the elapsed time of the minimum discharge capacity operation is greater than a predetermined time and when the impressed voltage of the evaporator fan is greater than a predetermined voltage.

Abstract: Control apparatus for an environmental control system comprises input circuitry receiving environmental information and output circuitry for controlling an HVAC system. Processing circuitry in the controller configures the output circuitry based at least in part on the signals received on the input circuitry. Information about the status of the HVAC system may be transferred to system administrators using a wireless link.

Abstract: A temperature management apparatus for foodstuffs stored in a storage cabinet, wherein a temperature sensor is placed in the storage cabinet to detect an inside temperature of the cabinet thereby to calculate an ambient temperature of the foodstuffs based on the detected inside temperature, and wherein an internal temperature of the foodstuffs is presumed on a basis of the calculated ambient temperature. The temperature management apparatus is provided with a foodstuff temperature indicator for indicating the presumed internal temperature of the foodstuffs and an alarm device for issuing an alarm sound when the presumed internal temperature of the foodstuffs becomes lower than a lower limit temperature or higher than an upper limit temperature.

Abstract: A vehicle air conditioner includes a variable displacement compressor forming a part of a coolant circuit, detectors for detecting external information necessary for air conditioning, and a controller. The compressor has pistons and mechanism for actuating the pistons to draw, compress and discharge refrigerant. The piston actuating mechanism is located in a crank chamber. The pressure in the crank chamber is changed to vary the compressor displacement. The controller controls the compressor based on the information from the detectors. When disengaging an electromagnetic clutch, which is located between a vehicle engine and the compressor, the controller quickly decreases the compressor displacement and prevents the pressure difference between the crank chamber and compression chambers excessively increased. Therefore, immediately after being stopped, the compressor is started at the minimum displacement, which minimizes the shock due to load torque change on the engine.

Abstract: It is an object of the present invention to provide an operation control method of an air-conditioning apparatus and an air-conditioning apparatus that prevent a plurality of air-conditioning apparatuses from simultaneously restarting upon their automatic recovery after a recovery of power and from stopping again due to a voltage drop. The air-conditioning apparatus of the present invention is provided with an automatic recovery control circuit (21) for deciding a delay time until a restart based on set data for deciding operation works of the air-conditioning apparatus or randomly, thereby to restart the air-conditioning apparatus with the decided delay time.

Abstract: The present invention is direct to a system and method for electronically controlling the refrigeration and/or heating of the product storage compartment in a vending machine. The system includes a temperature sensor for sensing the temperature in the product storage compartment, and a door sensor for sensing whether the door is open or closed. The control method includes the steps of activating a defrost mode, which is a timed period with no heating or cooling activity, when the door to the vending apparatus is open. The defrost mode is also activated whenever the cooling element has been running continuously for several hours. Further, the control method includes a step of cycling the cooling element “on” whenever a predetermined high temperature is reached. When the cooling element is “off” for more than 6 hours and the predetermined high temperature has not been reached, the heater is turned “on” to prevent the products in the vending machine from freezing.

Abstract: A refrigerator having a refrigerator evaporator and a freezer evaporator, capable of controlling the refrigerant circulation correctly and reducing the delay in the refrigerant behaviors. When freezer mode is to be switched to refrigerator mode, at the end of the freezer mode, a refrigerant recovery run recovers the refrigerant from the freezer evaporator and feeds it to a condenser before the refrigerator mode by running a compressor while blocking the refrigerant to the freezer evaporator and by running a compressor fan.

Abstract: When a single-stage thermostat is appropriately connected to a two-stage cooling system, a microprocessor control activates low and high stages of cooling based on preset parameters. The cooling load requirement is determined and compared to the maximum load requirement that can be satisfied in low-stage cooling mode and the minimum load requirement which can be satisfied in high-stage cooling mode. The desired low-stage cooling time limit is then determined for the next cycle. After the first cycle, the desired low-stage cooling time limit may be equal to zero in which case the next cycle is spent in high-stage cooling mode, or, if greater than zero, the next cycle runs in low-stage cooling mode up to the desired low-stage cooling time limit, with an additional high-stage cooling mode run if the thermostat is not satisfied within the desired time.

Abstract: A cooling system and related method of defrosting a refrigeration unit or a freezer unit involves the steps of (a) monitoring a compressor running time, (b) monitoring an evaporator coil temperature, (c) monitoring a first time period since a last cooled compartment door open alarm of the unit, (d) monitoring a second time period since a last defrost operation, (e) monitoring a third time period during which the cooled compartment door is closed, and (f) controlling initiation of a defrost operation as a function of the monitored compressor running time, the monitored evaporator coil temperature, the monitored first time period, the monitored second time period, and the monitored third time period. Various sets of conditions may be established for triggering initiation of the defrost operation. The system may also detect refrigerant leaks and a clogged condenser as a function of compressor running time and compressor discharge line temperature.

Abstract: An air conditioning system for use in a motor vehicle powered by an internal combustion engine is described. The system comprises an electric motor powered by a battery; a compressor arranged to be powered by at least one of the internal combustion engine and the electric motor; and a control unit that controls the driving of the compressor. The control unit is configured to execute driving the compressor by only the electric motor when the combustion engine is under an idling stop; restarting the combustion engine upon expiration of a first given time from the time when the idling stop has occurred, so that thereafter the compressor is driven by both the combustion engine and the electric motor; and stopping the driving of the compressor by the electric motor upon expiration of a second given time from the restarting of the combustion engine, so that thereafter the compressor is driven by only the combustion engine.

Abstract: The present invention provides an improved system and method for sensing of ice, particularly applicable in the control of ice thickness in automatic ice-making machines. The ice-making machine may be of the conventional type using a cold plate with water flowing over it. A thermistor bead temperature sensor is encapsulated in a metal housing, which is in turn mounted on a carrier. The position of the carrier is adjustable relative to the cold plate. The control system has several variable delays or time durations which optimize system performance: 1. Minimum harvest time delay, relative to the start of the ice-making cycle; 2. Threshold persistence time delay, requires that the signal sensor persists above the harvest threshold value for a certain amount of time (referenced to when the threshold is first exceeded), before harvesting may begin; 3. Harvesting delay is an optional delay provided give the option of making sure the ice is sufficiently “cured.

Abstract: A control system for a reversible heat pump includes a system controller which polls the heating or cooling demands of zone controllers associated with a series of heat exchangers downstream of the heat pump. The system controller is operative to configure the heat pump in response to which of the demands is dominant. The system controller is also operative to change the configuration of the heat pump in response to a change in dominant demand. The implemented change in heat pump configuration is preferably premised on the temperature of water returned to the heat pump being within a predefined range of temperature. The return water temperature requirement may be overriden by the system controller if an acceptable period of time for allowing the returning water temperature to reach an acceptable temperature level has elapsed.

Abstract: An ice making machine controller system includes methods and components for making commercial quantities of ice pieces includes adaptive controls responsive to input sensors, output actuators, adaptive ice making control algorithms, adaptive ice harvesting control algorithms, diagnostics for operation cycle monitoring and communicating, and reprogrammable, expanded controller memory for reliable and efficient operation under diverse conditions.

Abstract: A compressor driving apparatus comprises a module including a power supply, an inverter for driving a compressor, an inverter driver for driving the inverter, a CPU for generating a signal to be used for driving the inverter and having a function for communicating with outside, a storage circuit for storing data which is alterable from an external device, and a relay driver for driving an external relay. The inverter and other circuit components are disposed within the module such that they are thermally separate such that an inverter driving signal from the CPU is transferred accurately to the inverter and that a power supply having an output voltage with low distortion is realized, thereby improving the operating efficiency of the compressor. Because the storage circuit and the power supply circuit are built-in, standardization of the compressor driving apparatus is easily realized.

Abstract: A refrigerator includes a compressor, a condenser for liquefying a refrigerant discharged from the compressor, a plurality of refrigerant passages disposed at a downstream side of the condenser, a switching valve for switching a flow of refrigerant to one of the refrigerant passages so that the refrigerant liquefied by the condenser flows through the selected refrigerant passage, the switching valve including a valve body, and a controller for controlling the switching valve so that the switching valve performs a switching operation upon expiration of a period of time sufficient for an interior of the valve body of the switching valve to be filled with the liquid refrigerant after start of the compressor.

Abstract: The present invention is direct to a system and method for electronically controlling the refrigeration and/or heating of the product storage compartment in a vending machine. The system includes a temperature sensor for sensing the temperature in the product storage compartment, and a door sensor for sensing whether the door is open or closed. The control method includes the steps of activating a defrost mode, which is a timed period with no heating or cooling activity, when the door to the vending apparatus is open. The defrost mode is also activated whenever the cooling element has been running continuously for several hours. Further, the control method includes a step of cycling the cooling element “on” whenever a predetermined high temperature is reached. When the cooling element is “off” for more than 6 hours and the predetermined high temperature has not been reached, the heater is turned “on” to prevent the products in the vending machine from freezing.

Abstract: An integrated heat pump and electrical heat control (12) has thermostat signal inputs (O, W1, W2, G, Y) along with a defrost sensor input (DF_IN). The defrost sensor (22) is located in an outdoor unit (4) which also includes a compressor contactor (CC), condenser fan (16) and reversing valve (18) relays (K4, K3, K2) controlled by micro-controller (U1). The normally closed condenser fan relay (K3) is energized through the defrost sensor forming a hardware lock-out in which the defrost sensor contacts must be closed for relay (K3) to be actuated de-energizing the condenser fan. The compressor contactor (CC) is energized through a low pressure switch (24) and high pressure switch (26) forming another hardware interlock. The evaporator fan is energized by relay (K1) controlled by micro-controller (U1) and matched to the compressor for improved efficiency and comfort.

Abstract: A programmable electronic start-up delay for delaying the start-up of refrigeration units (10, 12, 14) for a user-programmable variable delay period. The delay permits a group of refrigeration units all powered by the same source (16) to be restarted at different time intervals after a power failure to prevent overloading of the power source or associated circuitry.

Abstract: A circuit configuration operates an electrically triggerable magnet valve having a valve-control element adjustable into at least two working positions for selecting one fluid-flow path at a time to be acted upon by a fluid and corresponding to a respective working position. The circuit configuration includes a device for adjusting the valve-control element into a different working position in connection with an imposition of fluid, predominantly present in liquid components, on at least a portion of a fluid-flow path formed by the magnet valve. A refrigeration appliance, in particular a refrigerator or freezer or a combination refrigerator-freezer includes the circuit configuration.

Abstract: A device for controlling an HVAC system in which opening a door or window for more than a shutdown delay period causes the fan and compressor to be deactivated, but opening and closing the door or window for less than the shutdown delay period does not affect the fan and compressor. Reactivation of the compressor is delayed for a startup delay, in order to avoid overcycling of the compressor and the additional wear and tear and maintenance that would be caused thereby. Preferably, the door/window sensors are wireless for ease of installation and maintenance. Optionally, an occupancy sensor and occupancy timer are provided to turn off the system if the room is unoccupied for an unoccupied delay time. Optionally, a secondary thermostat with energy saving settings is provided so that if the room is unoccupied for the occupancy delay, then instead of being shut off, the HVAC system will be operated at energy saving settings.

Abstract: A refrigerating system is proposed which comprises a cooling circuit 7 for cooling a cooling room 3, the cooling circuit 7 comprising an evaporator 9 arranged in the cooling room 3 and passed by a coolant and the power to be supplied to the cooling circuit 7 being adjustable, a control device 23 for making available to the cooling circuit 7 a performance value stating the power to be supplied, a temperature sensor 27 for making available to the control device 23 a temperature measurement value essentially stating the temperature of the coolant in the evaporator 9, a clock 29 for making available to the control device 23 a predetermined first time interval and a pre-determined second time interval following the first time interval, wherein the control device 23 during the first time interval makes available a first performance value stating an essentially constant first power to be supplied and after the end of the first time interval makes available a second performance value stating a second power to be supp

Abstract: A control system for mobile air conditioning systems for controlling the rate at which the system compressor or clutch is cycled between operational and decreased refrigerant flow, by selectively controlling the response time of certain system control signals to flow demand changes including de-icing control, from interactions between de-icing control and flow control valves, as well as system overall control. Upon the detection of an icing condition, the response of the control system is delayed to a degree to control the rate at which the capacity of the compressor can be cycled with in design limits. The delay feature allows the differential used in differentiating between icing and non-icing conditions to be significantly reduced over that required in the prior art and thereby improving the performance of the air conditioning system.