Abstract: A method of controlling the temperature in cavities of a refrigerator (10) cooled by a refrigeration circuit having a compressor (18) and an evaporator (32) includes the steps of: monitoring the duty cycle of the compressor (18); determining whether the duty cycle is below a threshold; determining whether the temperature of the evaporator (32) is above a threshold; and if the duty cycle is below the threshold and if the evaporator temperature is above a threshold, activating the refrigeration circuit to start cooling of at least one of the refrigerator cavities. A refrigeration appliance (10) with a controller that activates the refrigeration circuit based on the monitored duty cycle of the compressor (18) and the evaporator temperature is also provided.

Abstract: The smart desert geothermal heat pump for air conditioning and domestic water cooling includes a heat pump having heat exchange piping adapted for installation underground in desert sand adjacent a structure to be heated/cooled. The heat pump draws heat from the sand to heat air in the structure in a heating cycle and draws heat from the structure to sink in the ground in a cooling cycle to cool the structure. A processor has an artificial intelligence machine learning unit configured to store historical weather data and mean heat pump on/off times by calendar date in Big Data tall arrays, and periodically re-computes mean heat pump on/off times by calendar date. A controller connected to the processor and at least one switch on the heat pump automatically switches between heating and cooling cycles and turns the pump on and off according to the median re-computed heat pump on/off times.

Abstract: A refrigerator, a refrigerator management system, and a control method for a refrigerator are capable of enhancing a power-saving effect of the refrigerator. The refrigerator includes: a main body having a storage chamber; a refrigeration cycle device including a compressor and a cooler; an air blower configured to blow cooling air cooled by the cooler to the storage chamber; a blowout volume control device configured to control a blowout volume of the cooling air to be blown out to the storage chamber; input means for receiving input of schedule information that is information about a schedule of a user; storage means for storing the schedule information input into the input means; and control means for controlling at least one of the compressor, the air blower, and the blowout volume control device based on the schedule information.

Abstract: The invention relates to a method for controlling a refrigeration system by establishing a defrost period during an initial defrost period. One or more compressors of the refrigeration system are monitored to establish if the one or more compressors are running, and a parameter representative of the one or more compressors running is monitored. The monitoring establishes at least one parameter limit value representative of whether a defrost period or a non-defrost period is to be initiated. The invention also relates to a method for controlling a refrigeration system subsequent to an electrical power interruption. The invention also relates to control units for applying one or both of the methods according to the invention, and to a refrigeration system having one or more control units controlling the refrigeration system according to one or both of the methods.

Abstract: A control method of a refrigerator including a compressor to supply refrigerant to an evaporator to cool a storage compartment, a valve to adjust flow of the refrigerant, a fan to blow air heat-exchanged by the evaporator, and a heater to remove frost from the evaporator. The control method includes, upon receiving a power-saving signal, determining whether the received power-saving signal is a first or second power-saving mode signal, upon determining that the power-saving signal is the first power-saving mode signal, performing at least one selected from among resetting of target temperature of the storage compartment, adjustment of an operation rate of the compressor, and adjustment of operation time of the heater to execute a first power-saving mode, and, upon determining that the power-saving signal is the second power-saving mode signal, controlling the compressor, the fan, and the heater to be off to execute a second power-saving mode.

Abstract: Systems and methods for transporting a hydrocarbon are provided. The method can include introducing a fluid at a first pressure and a first temperature to an inlet of a pump and pressurizing the fluid within the pump to produce a pressurized fluid having a second pressure and a second temperature. The method can also include flowing at least a portion of the pressurized fluid through a first heat exchanger and back to the inlet of the pump. The heat exchanger can include a coil having an inlet and an outlet and a housing at least partially enclosing the coil and having a first opening and a second opening. A first end of the coil can be disposed proximate the first opening. The heat exchanger can also include a foundation for supporting the coil and the housing.

Abstract: A heat pump system including a water reservoir tank, positioned proximate to a building, having a remote heat source associated therewith and ducting for drawing the heat source to the tank. The tank has an evaporator and a fan positioned to draw heat from the heat source and transfer the heat to the evaporator and a compressor for transferring the heat to the tank. A smart controller designed to optimize the efficiency of the heat pump water heaters may be used. The controller uses various inputs including ambient conditions and water consumption data to make an intelligent decision on when to run the system, based on a set of user preferences.

Abstract: Disclosed are a heat pump boiler and a control method for the same. The heat pump boiler includes an outdoor unit having an outdoor-unit heat-exchanger, a water pipe including a water-feed pipe and a water-return pipe connected to the outdoor unit to feed water to the outdoor unit or to return low-temperature or medium-temperature water produced in the outdoor unit to an external location, heat exchangers connected to the water pipe to produce medium-temperature or high-temperature water, a variable-capacity compressor connected to the heat exchangers, a buffer tank connected to the water pipe, and an externally-wound heat exchanger to collect waste heat radiated from the compressor. A temperature of water stored in the buffer tank is raised using the collected waste heat, and, during a defrosting operation, the water stored in the buffer tank is fed to the outdoor-unit heat-exchanger to defrost an evaporator of the outdoor unit.

Abstract: A method for configuring a controller for an HVAC system. The method comprises providing a closed loop refrigerant system and a control system to control the closed loop refrigerant system. The control system comprises a controller, an input device, and a processor including a signal sensing circuit. The input device is activated to provide one or more signals to the controller to control the components of the closed loop refrigerant system. One or more signals are sensed with the signal sensing circuit to determine whether signals are present between the input device and the controller. The signals are processed with the processor to determine what type of closed loop refrigerant system is present. The controller is then configured to control the type of system determined by the processor.

Abstract: The invention relates to a method for regulating a coolant circuit (2) of a vehicle air conditioning system (4). According to said method, a target value (SW(VT)) for an evaporator temperature (VT) is predetermined in a base control circuit. Said value is used to determine a control value (U) for controlling the evaporator temperature (VT) by means of an evaporator temperature regulator (16). Said control value is also fed to a ventilator fan controller (26).

Abstract: A refrigerant system comprising a compressor, a condenser, an electronic expansion valve, and an evaporator is controlled in a normal operating mode to meet moderate cooling loads; however, when the load approaches that which is sufficient to induce liquid refrigerant carryover from the evaporator to the compressor, the system is controlled in a capped operating mode to limit a certain thermodynamic variable rather than controlled to meet the high load. In the normal mode, the compressor and/or the expansion valve might be controlled in response to the amount of superheat of the refrigerant leaving the evaporator or the level of liquid refrigerant in the evaporator. In the capped operating mode, the compressor and/or the expansion valve might be controlled to limit a variable such as the compressor's capacity, the saturated pressure or dynamic pressure of the refrigerant entering the compressor, or the refrigerant's mass flow rate.

Abstract: A refrigerant system includes a controller that enables the system to dehumidify the air in a room without relying on a humidistat and without having to operate the system's compressor and electric heater at the same time. To dehumidify the air, the system's compressor, supply air fan, and outside air damper are controlled in a manner similar to other systems operating in a cooling mode when the room temperature is above a certain setpoint temperature. When the room temperature falls below the setpoint, however, the operation changes significantly. The controller closes the outside air damper, decreases the speed of the fan, and continues operating in this manner until the room temperature decreases to a subcooling temperature limit. The subcooling temperature limit is less than a predetermined limit that is used during the system's normal cooling mode.

Abstract: According to one embodiment of the invention, a method for regulating temperature in a system comprises receiving, at a building management system, information concerning a degree of opening of a plurality of control valves. Each of the plurality of control valves is associated with at least one terminal that is in communication with a supply header line of a system, and is operable to open or close according to its own logic based on the demand of the associated terminal or terminals. A determination is made, based on the degree of opening of the plurality of control valves, as to whether changes need to be made to the operating parameters of production equipment of the system. The changes to the production equipment operation of the system are operable to change at least one parameter of a fluid being supplied to the supply header line of the system. An initiation of changes is made if it is determined that the change needs to be made.

Abstract: An aircraft galley air cooling system utilizes a controller having software for regulating the temperature within food carts within a galley air cooling unit. The cooling unit includes supply air and return air temperature sensors which measure the temperature of the air entering and exiting the food cart. The return air temperature is regulated by controlling the amount of a liquid refrigerant that flows through a heat exchanger within the cooling unit. If the return air temperature sensor fails, then the controller regulates the supply air temperature. The controller also regulates defrosting of the cooling unit.

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: Disclosed is a refrigerator comprising at least one chamber and a temperature adjuster adjusting an temperature inside the chamber, further comprising a first temperature sensor approximately sensing the temperature inside the chamber, a second temperature sensor spaced from the first temperature sensor so as to sense the real temperature inside the chamber; and a controller controlling the temperature adjuster according to the temperature sensed by the second temperature sensor when the temperature sensed by the first temperature sensor is within predetermined temperature limits of the chamber and the temperature sensed by the second temperature sensor is not. With this configuration, the temperature inside the chamber is effectively controlled by an accurate and prompt sensing operation. Though one of the first and second temperature sensors is abnormal, it is possible to replace or repair the abnormal temperature sensor, or to control the temperature adjuster by the other normal temperature sensor.

Abstract: A refrigeration system including an evaporator, a suction header in fluid communication with the evaporator, a compressor in fluid communication with the suction header, and a condenser in fluid communication with the compressor and the evaporator. The refrigeration system further including a controller operable to control the compressor and a sensor coupled to the compressor. The sensor is operable to acquire a parameter for the compressor. The method of operating the refrigeration system includes acquiring a value for the parameter with the sensor, and determining if the sensor is faulty.

Abstract: A method of operating a refrigeration system having a discharge port that guides conditioned air from the system to a conditioned space and a return port that guides air from the conditioned space back to the system. The method comprises providing a first control algorithm and second control algorithm for controlling the system. The first control algorithm is a function of the air temperature at the discharge port, and the second control algorithm is a function of the air temperature at the return port. The method further comprises operating the system using the first control algorithm when a first condition is met, operating the system using the second control algorithm when a second condition is met, and automatically switching between the first control algorithm and the second control algorithm depending on the status of the first and second conditions.

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: In a chiller, an apparatus and method for automatically identifying a temperature probe for use in a chilling operation is provided in order to reduce user error. In the place of manual selection by a user, automatic selection of the appropriate temperature probe is accomplished by comparing the temperature of the given temperature probe to a threshold temperature. An additional apparatus and method for filtering a displayed compartment temperature is provided to reduce user confusion. The responsiveness of the displayed temperature to temperature changes in the compartment is reduced when the compartment door is opened.

Abstract: A method of controlling an expansion valve including the steps of: measuring a primary system condition; determining an error in the primary system condition; measuring a secondary system condition; determining an error in the secondary system condition; and modulating the expansion valve based upon the larger of the first or second error.

Abstract: A thermal storage monitoring and control system employed on a container refrigeration unit utilizes a "thermal flywheel" algorithm in combination with a data processor to control the temperature level within a cargo container to a maximum value. The thermal monitoring and control system operates the refrigeration system in a manner that causes the heat gain by the load during hot afternoons and evenings to be offset by the thermal storage built into the cargo. The monitoring and control system can be configured to operate automatically or manually.

Abstract: A method of controlling compressor minimum capacity. The method comprises the steps of: measuring a first condition; comparing the first condition to a first setpoint to determine a first conditioned error; modulating compressor capacity relative to the first condition error; measuring a second condition; comparing the second condition to a second setpoint to determine a second condition error; and modulating compressor capacity relative to the second condition error if the magnitude of the second conditioned error is greater than the magnitude of the first conditioned error.

Abstract: A control arrangement for cooling of an apparatus comprising a compressor, a condenser, and at least one branch with an expansion valve and an evaporator in series, contains a controller, a superheat temperature measuring device, and an ambient temperature sensor. The controller controls the expansion valve for maintaining the superheat temperature substantially at the desired value. The flow of coolant to the evaporator is controlled by the signal from the temperature sensor for maintaining the ambient temperature constant. The controller operates continuously and in two operating modes in which the first mode the superheat temperature is controlled to the maximum admissible state of fill of liquid coolant in the evaporator and is switchable to a second mode in which the state of fill of liquid coolant is controlled by the expansion valve.

Abstract: When a defroster switch is input in a heating operation mode, an opening degree of an electric type of a heating expansion valve is controlled to be smaller when temperature of refrigerant discharged from a compressor is less than a predetermined temperature. Therefore, the supercooling degree of the liquid refrigerant of an indoor heating heat exchanger becomes large, the temperature of the heat exchanger becomes high, so that the temperature of air which is blown from a defroster outlet becomes high. Thus, the defrosting effect of a front windshield glass can be increased. Accordingly, when the defrosting of the front windshield is needed, the defrosting effect is increased as compared with when the defrosting is not needed.

Abstract: Merchandise temperature sensors 16 for detecting merchandise temperatures simultaneously with in-housing temperature sensors 17 for detecting the in-housing air temperature of a merchandise housing are provided in the merchandise housing of a vending machine. Further, the cooling mechanism is controlled by means of the merchandise temperature sensor 16 during the peak shift or peak cut, whereas the cooling mechanism is controlled by means of in-housing temperature sensor 17 during normal operation. Thus the merchandise temperature is directly detected during the peak shift or peak cut where the temperature sharply varies so as to increase merchandise temperature control accuracy. Even when the installation of the merchandise temperature sensors is limited to some columns in view of cost reduction, the cooling mechanism is made controllable by collectively detecting the merchandise temperature in the whole column by means of the in-housing temperature sensors 17 during the normal operation.

Abstract: A thermostat has terminals to receive at least two temperature sensor signals, and changes the one of these terminals which provides the feedback signal for temperature control responsive to a detected condition. This condition may be a manual input, expiry of a time interval, reaching a time of day, or the relative magnitudes of the temperatures encoded in the sensor signals.

Abstract: A refrigerator having a cabinet defining a first compartment and a second compartment separated from each other by a divider wall wherein the divider wall has an air passage for communicating between the first and second compartments. The refrigerator further includes an evaporator disposed in the first compartment, a compressor fluidly connected with the evaporator for moving refrigerant therethrough, and an evaporator fan for moving air over the evaporator. A first thermostat senses temperature within the first compartment and a second thermostat senses temperature within the second compartment. An evaporator fan and baffle control system is provided including a baffle disposed within the air passage and being positionable in an open or closed position for selectively opening and closing the air passage.

Abstract: The object of the present invention is to make it easy to separate a portion which takes charge of the operation control of an air conditioner from the air conditioner using a remote controller, and the essential points are that the control means of the air conditioner controls the operation of a compressor to make the room temperature detected by a first temperature sensing means approach to a set temperature set by a first temperature setting means, and further comprises a changeover switch, and a means for controlling the operation of the compressor based on a signal from the remote controller when the changeover switch is in a valid state; the remote controller disposed being detached from the air conditioner comprises a second temperature sensing means for detecting the room temperature and a second temperature setting means for setting a desired temperature and transmits a signal for controlling the operation of the compressor to make the temperature detected by the second temperature sensing means appr

Abstract: Apparatus for and method of long-term control of the temperature within a refrigerated space, such as the cargo compartment of a refrigeration truck. The technique employs sensors which monitor both discharge and return air. A control algorithm uses the multiple sensors to control modes of a refrigeration unit capable of supplying cooled or heated air. This causes the temperature within the refrigerated space to remain within a narrow range about a target temperature. The target is chosen to provide maximum safety for the cargo. If the target temperature is too high, the cargo is needlessly exposed to spoilage. If the target temperature is too low, the cargo is subject to the risk of damage from freezing.

Abstract: A method of operating a transport refrigeration unit with microprocessor based control. The microprocessor automatically selects an operative control algorithm, according to system configuration, with each algorithm having one or more operating conditions. Return air and discharge air temperature sensors provide inputs to the microprocessor. First, second and third sets of look-up tables are accessed by the microprocessor to determine which conditions are in the selected algorithm, and the high and low trip points of each condition. The first set of tables is accessed when the return air sensor is functional, the second set is accessed when the discharge air sensor is functional and the discharge air sensor is not, and the third set is accessed when both the return air and the discharge air sensors are not functional and the conditioned load is frozen. Failure of both sensors when the load is fresh shuts the unit down.

Abstract: A compressor drive system that includes a thermostat producing a signal indicating the measured air temperature, a modulation control circuit connected to the thermostat to produce a motor drive signal from the temperature signal and which is output to a motor drive switching bridge circuit. The motor drive switching bridge circuit is connected to a rectifier that converts single phase alternating current to direct current. The switching bridge uses the motor drive signal from the modulation control circuit and the rectifier output to produce multiphase power including a speed control signal imposed on the power for regulating speed. A motor connected to drive a compressor is included. The motor is powered by the motor drive switching bridge circuit multiphase power output. The speed of the motor is controlled as a function of the temperature signal.

Abstract: An automotive air tempering apparatus for use in an automotive vehicle having a duct through which air is directed into a passenger compartment. The apparatus comprises an air chilling unit including an evaporator provided in the duct and a compressor having a displacement variable for supplying a controlled amount of refrigerant to the evaporator for chilling the air in the duct. A control unit controls the displacement of the compressor to bring the refrigerant temperature to a target value when air is introduced into the duct from the atmosphere. The control unit controls the displacement of the compressor to bring the chilled air temperature to a target value when air is introduced into the duct from the passenger compartment.

Abstract: An air-conditioning system controls the temperature of the air flow such that a deviation of an interior temperature of the passenger compartment of the vehicle determined by an interior temperature sensor from a givable desired temperature becomes minimal (interior temperature control). In the case of vehicles with closable vehicle body openings, such as a convertible, a switching device is provided which detects the condition of the vehicle body opening and, when the vehicle is open, causes a switching-over of the air-conditioning system from interior temperature control mode to a blow-out temperature control mode.

Abstract: A transport refrigeration system having a refrigerant compressor which is selectively operable with either an electric motor or an internal combustion engine. The transport refrigeration system conditions a load space to a selected set point via heating and cooling modes in response to a selected one of either a return air sensor or a discharge air sensor. System control is automatically optimized in response to manual selections of the prime mover and the operative sensor by providing first, second, third and fourth control algorithms. Selection of the return air sensor automatically selects the first and third control algorithms for electric motor and internal combustion engine, respectively, and selection of the discharge air sensor automatically selects the second and fourth control algorithms for the electric motor and internal combustion engine, respectively.

Abstract: An automobile air-conditioner wherein a total signal corresponding to a thermal load in the passenger compartment of an automobile and a head part total signal corresponding to a thermal load in the vicinity of the head of an occupant of the passenger compartment, then the thus obtained two total signals are used to determine two corresponding states of operation of a component involved in air-conditioning operation, and operation of the air-conditioning component is controlled based on one of the two total signals which is capable of providing an enhanced coolness to the occupant. According to a preferred embodiment, all the components involved in the air-conditioning operation are controlled based on the head part total signal.

Abstract: A compressor drive system that includes a thermostat producing a signal indicating the measured air temperature, a modulation control circuit connected to the thermostat to produce a motor drive signal from the temperature signal and which is output to a motor drive switching bridge circuit. The motor drive switching bridge circuit is connected to a rectifier that converts single phase alternating current to direct current. The switching bridge uses the motor drive signal from the modulation control circuit and the rectifier output to produce multiphase power including a speed control signal imposed on the power for regulating speed. A motor connected to drive a compressor is included. The motor is powered by the motor drive switching bridge circuit multiphase power output. The speed of the motor is controlled as a function of the temperature signal.

Abstract: Provision is made in a multiple zone air conditioning system for varying the speed of the compressor to match the load thereon. The differences between the actual temperatures and the set points in the individual zones are monitored and the largest of these differences is periodically selected and applied to a transfer function to obtain a new speed at which the compressor is run. At the same time, the individual dampers within the zones are modulated in response to their respective sensed temperature differences. Provision is also made to vary the speed of the indoor fan in a similar manner.

Abstract: A refrigeration system having two evaporators to function as both an air conditioner and refrigerator of a vehicle is disclosed. The two evaporators are connected parallel with one another, with one of the two evaporators being disposed in the duct portion of the air conditioner and other being disposed in the refrigerator. An electrical expansion valve is serially connected with the inlet side of the air conditioner evaporator for controlling the flow of refrigerant to it. A shutoff valve for controlling the opening and closing of the line, and an expansion device, are serially connected ahead of the inlet side of the refrigerator evaporator. When the shutoff valve is closed, the operation of the electrical expansion valve is controlled by the change in temperature of refrigerant through the air conditioner evaporator; and when the shutoff valve is open, the operation of the expansion valve is controlled by the temperature of refrigerant in the refrigerator evaporator.

Abstract: This apparatus selects a start-up mode of operation for controlling the compressor (1) at maximum speed only when the difference between the measured temperature of a room at the start of the operation and a target temperature is larger than a predetermined value. A normal mode of operation otherwise is selected for controlling the compressor (1) at a speed lower than maximum thus extending the life of the compressor (1).

Abstract: A method for controlling a temperature of an object to be cooled or heated by a cooling/heating apparatus is improved in that when all of a plurality of temperature detectors for detecting a temperature of the object are operating normally, the cooling/heating capacity of the cooling/heating apparatus is regulated in response to input signals consisting of the detection temperature of the respective temperature detectors according to an operation pattern set in a normal time thermostat. When it has been determined that a certain temperature indicated by a detector is abnormal, then the cooling/heating capacity of the cooling/heating apparatus is regulated in response to input signals consisting of the detection temperatures of the other normal temperature detectors according to an operation pattern set in an abnormal time thermostat that is different from the operation pattern set in the normal time thermostat; thus the temperature of the object can thereby be controlled.

Abstract: In a heating and/or air-conditioning system for motor vehicles with a temperature sensor in the head space and a temperature sensor in the leg space as component parts of an interior space temperature regulating installation, the temperature sensors are so connected to the regulating installation in dependence on the outside temperature that at low, respectively, high outside temperatures, the influence of the leg space, respectively, of the head space temperature sensor on the regulating installation dominates.

Abstract: A refrigerating apparatus adapted for storage of cold storage goods as well as frozen goods and having both a heater and a cooler is controlled by an improved temperature control device, which includes a detector for detecting a temperature of return air from the interior of a storage area of the refrigerating apparatus and a detector for detecting a temperature of an air output which is blown into the interior of the storage area, and which controls either the higher one of the two detected temperatures or the lower one of the two detected temperatures depending upon a set temperature. In the case of storing cold storage goods, the lower one of the two detected temperatures is controlled so as to be maintained at the set temperature, whereas in the case of storing frozen goods, the higher one of the two detected temperatures is controlled so as to be maintained at the set temperature.

Abstract: The present invention relates to a control device for an auxiliary member of vehicles which is capable of suspending the driving of the auxiliary member of a vehicle such as a compressor for air conditioning device when there is a sudden increase of the load on the driving system of the vehicle and which is also capable of driving the auxiliary member as much as possible when the engine is operating below its maximum capacity. The control device comprises a means to detect the load of the driving system of a vehicle and the rate of acceleration of said load, a means to control the driving of an auxiliary member which is driven by the engine of the vehicle, and a means to transmit a signal to the driving mechanism of said auxiliary member to suspend its driving from the time when the acceleration of the load of the driving system of the vehicle exceeds a predetermined value until the time when the load returns to the predetermined value.

Abstract: A control means is disclosed that is used with a closed refrigeration system having a chiller and a condenser to provide refrigeration to chill the fluid medium and a refrigerant pump for pumping the refrigerant through the system with refrigerant capacity control means determining the capacity of the refrigerant, the control means for the system using signal inputs representative of outside air temperature, return chilled water temperature, supply chilled water temperature, and condenser temperature, in which settable controllers are used to determine the optimum temperature signals for controlling the system at any given time. A timer is also connected to the control mechanism for alternately interrupting an optimum temperature signal to reduce the overall change in the control signal. Additional control may be obtained through the use of signals representative of humidity, strong solution temperature and cooling water output pressure.

Abstract: An automatically-defrosting household refrigerator including a user-operable "vacation switch" effective to enable the operation of the refrigerator in a mode appropriate to a condition of zero usage. When the vacation switch is thrown to the vacation position, the user is assured at once that unnecessary energy consumption will be avoided and the likelihood of failure of the refrigerator while unattended will be diminished. The mode appropriate to a condition of zero usage includes having the interval between successive automatic defrosting operations extended. Additionally, the vacation switch may be effective to simultaneously disable an automatic icemaker, to increase the temperature set point of the thermostatic control means which maintains the temperature within the refrigerator to disable anti-condensation heaters, and to disable butter conditioner heaters.There is further disclosed a particular means for extending the interval between successive automatic defrosting operations.

Abstract: A control circuit for a room air conditioner includes two temperature sensing devices and an associated switch network which operate to de-energize the evaporator fan upon de-energization of the compressor but, as the temperature of the room air subsequently rises, cause the evaporator fan to be energized prior to re-energization of the compressor. The evaporator housing and temperature sensing devices are arranged such that during operation of the evaporator fan one of the devices senses the temperature of air entering the evaporator while the other senses the temperature of air leaving the evaporator, but during periods when the evaporator fan is off the device which formerly sensed the temperature of air leaving the evaporator operates to sense the temperature of room air.

Abstract: A dual temperature refrigerator driven by a single compressor, having a refrigeration cycle provided with a condenser, a refrigerant metering device and refrigerant transfer lines with at least two evaporator sections connected in series with the first in a colder compartment and the second in a warmer compartment. Two separate, intermittantly activated control elements; one associated with the warmer compartment turns on a heater of a refrigerant collector causing refrigerant to discharge therefrom, and thereby to fill the evaporator of the warmer compartment, the second control element associated with the colder compartment is activated by a sensor in the colder compartment and in turn activates the compressor. The first control element indirectly activates the compressor by means of a second heating element which heats the sensor which in turn activates the second control element which in turn activates the compressor.

Abstract: This invention teaches a food storage refrigeration cabinet suited for operation either on a conventional refrigeration cycle or on a fast cool down refrigeration cycle. The disclosed cabinet has partition structure that separates a food storage space from a defined plenum, and the evaporator coil of the refrigeration system is located inside the plenum. The partition has inboard and outboard openings to define recirculating air flow paths over the evaporator coil from and to the food storage space. For use of the cabinet on a conventional refrigeration cycle, first fan means in the inboard openings draws air from the storage space and passes the same over the evaporator coil for discharge out the outboard openings back to the storage space, and the refrigeration system is cycled on and off in order to maintain the enclosure air within the proper temperature range.

Abstract: The invention relates to the air conditioning of a storage compartment and is especially significant for a transport system. Air is circulated between an air tempering zone and the storage compartment, said air tempering zone having air cooling means and air heating means controlled by a thermostat. The thermostat has a wide range set point and depending upon what set point is selected, the thermostat is responsive either to the temperature of the air discharged from the tempering zone or the temperature of the air returning to said zone. When the set point is above a given point and the air is being cooled to near the desired temperature, said desired temperature is accurately obtained by the thermostat first sending a signal from a selected one of the two sensors that provides a step-reduction in the capacity of the cooling means and then sending a signal to a modulating valve that further reduces to the set point the capacity of the cooling means by a modulation reduction.