Abstract: A method of preventing compressor surge in an air conditioning system comprises: 1) determining the refrigerant flow rate at the compressor; 2) determining the input pressure and output pressure at the compressor; 3) determining the pressure ratio (output pressure/input pressure) at the compressor; 4) defining a surge limit based upon the pressure ratio and the refrigerant flow rate; 5) processing system operational inputs including motor speeds and air conditioning pressures; and 6) sending control signals to the air conditioning system to control the refrigerant flow rate and the pressure ratio in a manner to prevent compressor operation at the defined surge limit and to maximize compressor efficiency during transitional periods. An air conditioning system is also provided, as well as an article of manufacture for use with the system for preventing compressor surge.

Abstract: A thermistor probe is formed in a closed end tube and the probe is inserted through the header of a receiver/drier in a refrigeration system for sensing the temperature of the saturated refrigerant vapor in the receiver/drier. The sensed temperature is employed to energize and de-energize the refrigerant pump or compressor. The sensed temperature is also employed to energize and de-energize the refrigerant condenser fan motor.

Abstract: An engine-driven heat pump apparatus having a refrigerant circulation line which includes at least one inside heat-exchanger for exchanging heat between the air in a room and the refrigerant, and a pressure-controlling device for substantially maintaining the pressure on the high pressure side of the refrigerant circulation line by, for example, narrowing the opening of the expansion valve(s), decreasing the volume of air passing through the inside heat-exchanger(s), recirculating the air passing through the inside heat-exchanger(s), lowering the heat efficiency of the engine when the required quantity of radiated heat from the inside heat-exchanger(s) in use is increased, e.g., when the number of inside heat-exchanger(s) in use is increased, thereby maintaining or increasing heating power in the heating mode, irrespective of the number of inside heat-exchangers in use.

Abstract: According to the present invention, in a gas injection type heat pump apparatus, the high-pressure side pressure of refrigeration cycle is detected in a heating operation, and an upper limit value of an amount of air passing through an inside heat exchanger is determined based on the detection value. The upper limit value and a set air amount set by an air amount switching lever are compared. When the set air amount is larger than the upper limit value, the amount of the air passing through the inside heat exchanger is restricted within the upper limit value. In this way, the high-pressure side pressure increases, and an intermediate pressure in a gas-liquid separator also increases. Therefore, the gas injection amount can be increased, and a heating capacity can be effectively improved.

Abstract: 1,3,5-Triazine-2,4,6-tris-alkylaminocarboxylic acid derivatives of the general formula (I): 1,3,5-triazine-2,4,6-tris?NH--(CH.sub.2).sub.n --CO--O--R.sup.1 ! are employed as biocidal or biostatic agents in aqueous systems, in particular in cooling lubricants. Fungicides, for example pyrithione or derivatives thereof and/or N-alkyl-diazenium dioxide salts, can be added to the aqueous systems. 0.05 to 0.40% by weight of the 1,3,5-triazine-2,4,6-alkylaminocarboxylic acid derivatives and 0.0001 to 0.2% by weight of fungicides are sufficient to maintain the biocidal or biostatic actions.

Abstract: An air conditioning apparatus, capable of cooling, dehumidifying, and reheating air, using refrigeration reheat. The apparatus comprises rooftop unit (1), which includes a standard refrigeration loop for cooling operation. A multiple circuit reheat coil (54), is added in a parallel arrangement with outdoor coil (34), with respect to refrigerant flow. A portion of the hot refrigerant gas of the system is diverted through reheat coil (54) during dehumidification mode, to reheat the supply air to room temperature. A multiple step discharge air control system is included to control multiple stop valves (52) during the dehumidification mode. Reheat coil (54) is arranged in series air flow relationship with evaporator coil (46), so that a mixture of any proportion of outside air and return air may be conditioned. A pressure control (28) is provided to maintain system pressure during all modes of operation.

Abstract: A refrigeration system includes in a closed loop connection a compressor for compressing a refrigerant, a desuperheater for cooling the hot compressor discharge gas via the injection of liquid refrigerant, and a condenser for condensing the compressed, desuperheated refrigerant into a liquid refrigerant. The liquid refrigerant is injected into the compressed refrigerant by utilizing a liquid column for supplying pressure to the liquid refrigerant for injecting liquid refrigerant into the compressed refrigerant without using a mechanical pump. Another method of injecting the liquid refrigerant into the compressed refrigerant is to use a venturi pump at the injection point to supply the liquid refrigerant for injection into the compressed refrigerant. The desuperheater causes the temperature of the hot refrigerant vapor leaving the compressor to be reduced from a superheated condition to temperature closer to its condensing temperature prior to its entry to the condenser.

Abstract: An automotive air conditioner which conditions air making use of radiation of heat of a condenser and absorption of heat of an evaporator effectively. The evaporator 207 and the condenser 203 are disposed in a duct 100. A bypass passageway 150 is provided sidewardly of the condenser 203 in the duct 100, and a flow rate of air bypassing the condenser 203 is controlled by pivotal motion of an air mixing damper 154. Another bypass passage is provided sidewardly of the evaporator 207 in the duct 100, and a flow rate of air bypassing the evaporator 207 is controlled by pivotal motion of a bypass damper 159. Air is conditioned to an optimum blown out air temperature by varying the cooling rate at the evaporator 207 and the heating rate at the condenser 203 and is blown out to a room of an automobile from spit holes 141, 142 and 143.

Abstract: An engine cooling fan control system includes a vehicle speed sensor, a pressure sensor for sensing the pressure of refrigerant provided to a refrigerant condenser forming part of the vehicle air conditioning system and a controller responsive to the vehicle speed and refrigerant pressure signals to operate an engine cooling fan. The engine cooling fan is activated continuously while vehicle speed is below a first speed threshold if the refrigerant pressure exceeds a first pressure. While the vehicle speed is above the first speed threshold, but below a second speed threshold, the engine cooling fan is activated for a predetermined duration if the refrigerant pressure is above the first pressure. Finally, while the vehicle speed is above the second speed threshold, the engine cooling fan is activated in response to the refrigerant pressure exceeding the first pressure and deactivated in response to the refrigerant pressure falling below a second lower pressure.

Abstract: Apparatus for providing integrated control of a space cooling system is disclosed. The apparatus receives inputs from a plurality of temperature sensors, including a temperature sensor for measuring evaporator superheat, space temperature and compressor discharge temperature. The control apparatus incrementally adjusts the position of the cooling system expansion valve to regulate evaporator superheat and compressor discharge temperature and cycles the outdoor condenser fan on and off to raise condenser pressure in response to a low condenser pressure condition. In one embodiment, the cooling system includes a plurality of evaporators and a corresponding plurality of controllers electrically interconnected in a series loop for controlling the expansion valves and defrost heaters associated with the respective evaporators.

Abstract: Liquid refrigerant temperature, measured by a sensor adjacent the flow control device, provides multiple diverse pieces of information which are used to control the indoor fan speed. liquid refrigerant temperature is used as an indication of outdoor air temperature and is also used as an indication of whether the compressor is operational or not.

Abstract: A compressor discharge pressure control for a unitary outdoor fan, multi-split air conditioning system having multiple compressors, multiple evaporator coils, multiple condenser coils and a single outdoor fan. Pressure comparison circuitry compares the discharge pressures of the compressors to predetermined pressure levels to generate a plurality of pressure state signals. On/off monitoring circuitry monitors the on/off states of the compressors to generate a plurality of compressor state signals. Control circuitry controls the fan in accordance with both sets of signals under a predetermined priority scheme.

Abstract: An air conditioner employs a refrigerating cycle in which a non-azeotropic mixture of high and low boiling coolants is sealed. The ratio between the high and low boiling coolants of the coolant mixture changes according to a change in the opening of an electric expansion valve 7. A level sensor 19 is arranged in an accumulator 17 that accumulates the liquid phase of the coolant mixture. A value detected by the level sensor is used to calculate the ratio between the high and low boiling coolants actually circulating in the refrigerating cycle. According to the opening of the valve 7 or the ratio between the actual quantities of the high and low boiling coolants, basic operation parameters such as the operation frequency of a compressor 1 are changed. This results in stabilizing and optimizing the operation of the refrigerating cycle even if a cycle temperature or pressure is changed due to a change in the ratio between the high and low boiling coolants of the coolant mixture.

Abstract: When the driver parks a truck for the purpose of sleeping in the cab's bunk space and desires to have the air conditioner operate, fan clutch cycling, which may create objectionable noise that disturbs sleep, is avoided by the inclusion of a branch circuit off of the air conditioner switch that comprises a parking brake switch in series with a relay coil. When the air conditioner is on and the parking brakes are set, this relay coil is energized to open a circuit to the engine fan clutch solenoid, preventing the fan clutch from being disengaged, and thereby keeping the fan in driven relation to the engine crankshaft so that fan clutch cycling does not occur.

Abstract: A refrigeration system includes a temperature sensor in a freezing compartment, a temperature sensor in a cooling compartment, an adjustable damper controlling the flow of cooled air from the freezing compartment to the cooling compartment and variable speed drives for fan motors and a compressor motor. The desired set point temperatures for the compartment are compared with the actual sensed temperatures through a controller that controls the speed of the compressor and fan motors, to achieve the desired temperature in a fast and efficient manner. When excessive ice is detected on freezing compartment coils, the controller reverses the heat transfer cycle of the refrigerant to defrost the freezing compartment coils.

Abstract: An air conditioner employs a refrigerating cycle involving a compressor 1, an outdoor heat exchanger 5, an indoor heat exchanger 9, an expansion valve 7, and a non-azeotropic coolant mixture composed of high and low boiling coolants sealed in the refrigerating cycle. The outdoor heat exchanger 5 is provided with a first blower 15 and a second blower 17. A speed controller 18 drives and controls the first, and second blowers 15 and 17. The speed controller 18 achieves a first mode to decrease an air quantity to part of the outdoor heat exchanger located on the upstream side of a flow of the coolant smaller than an air quantity to part of the outdoor heat exchanger located on the downstream side of the flow of the coolant, and a second mode to increase the air quantity to the upstream side of the outdoor heat exchanger greater than the air quantity to the downstream side of the outdoor heat exchanger.

Abstract: An air conditioning apparatus suitable for an electric powered automobile, where at least one of a heating and a dehumidifying operation is effected by utilizing a refrigerating cycle. An upstream heat exchanger and a downstream heat exchanger are arranged in a duct through which air passes for air conditioning. An outside heat exchanger with an outside fan are further provided, which act as a condenser in a cooling mode, although a refrigerant passes therethrough when using the heating and the dehumidifying modes. Upon use of a dehumidifying mode, the upstream heat exchanger acts as an evaporator, while the downstream heat exchanger acts as a condenser. The temperature of the refrigerant sensed by a temperature sensor at the outlet of the compressor if higher than a predetermined value (110.degree. C.

Abstract: A multiple type air conditioning apparatus includes a refrigerant supply unit having a variable capacity compressor, at least two internal air conditioning units each having an internal heat-exchanger and a fan device, the internal heat-exchangers of the at least two air conditioning units being connected in parallel to one another, a first variable expansion valve for variably throttling refrigerant, fed from the compressor, flowing through one of the internal heat-exchangers, a second variable expansion valve for variably throttling refrigerant, fed from the compressor, flowing through the other internal heat-exchanger and a variable flow rate control unit arranged at one side of the internal heat-exchangers from which refrigerant flows into each internal heat-exchanger in a heating operation, for regulating a distribution of refrigerant flowing into each internal heat-exchanger.

Abstract: Method and apparatus for remotely monitoring the condition of a heat transfer fluid in the liquid line of a heat transfer system. The operation of the system is controlled in response to the results of the remote monitoring which may be used to indicate excessive moisture in the heat transfer fluid, low levels of heat transfer fluid, and non-condensed transfer fluid in the liquid line. Based upon the monitoring of the transfer fluid for non-condensed fluid, the rate of movement of a cooling fluid past a condenser for the transfer fluid is varied so that the temperature of the heat transfer fluid is kept as low as possible without formation of bubbles of non-condensed transfer fluid in the liquid line.

Abstract: Supplementary cooling for a mechanical refrigeration plant using ammonia as a refrigerant is provided by placing a tube in the vapor space of a buffer vessel and introducing liquid nitrogen into the tube. Although ammonia solidifies at -78.degree. C. and liquid nitrogen enters the tube at -196.degree. C. no ammonia solidifies on the tube even after extended operation. The present invention also provides a method of refrigeration which comprises introducing liquid nitrogen into the heat exchanger of a refrigeration apparatus in accordance with the invention and condensing refrigerant therewith. Preferably, the refrigerant is selected from the group consisting of ammonia and fluorocarbon R22.

Abstract: A mass flow control apparatus and method for use in combination with a heat transfer system having a compressor, condenser, expansion valve, evaporator and working fluid in a s fluid circuit. The mass flow is controlled using a quality sensor for the working fluid exiting the evaporator, and a high side pressure sensor. A control circuit is provided that monitors the quality sensor and the high side pressure sensor, and controls operation of the compressor, condenser fan and valve in response thereto. A flow reduction mode is used to reduce high side pressure at the valve inlet without excessive compressor cycling by changing the quality sensor setpoint when the high side pressure exceeds the condenser fan turn-on pressure but is less than the compressor disengage pressure.

Abstract: An automobile condenser electric fan controller, which includes a high pass filter, an inverted comparator, and a relay, the inverted comparator comparing the signal obtained from the high pass filter with a reference DC level signal made according to predetermined critical speed and then providing a high potential or low potential output according to the comparison result, whereby the relay is controlled to turn on the automobile's condenser electric fan as the output of the inverted comparator and the output of the automobile's compressor both are at high potential; the relay is controlled to turn off the automobile's condenser electric fan as the output of the inverted comparator and the output of the automobile's compressor both are at low potential, or either one is at high potential while the other is at low potential.

Abstract: There is provided an air-conditioning apparatus. A cooling bypass extends from a pipe portion between a water heat exchanger and indoor heat exchangers of a refrigerating cycle to a low-pressure-side pipe portion of the refrigerating cycle. The cooling bypass is provided with a flow control valve. A discharged-refrigerant temperature Td and sucked-refrigerant temperature Ts of a compressor are sensed, and the opening degree of the flow control valve is zone-controlled in accordance with temperature Td or temperature Ts. When the sucked-refrigerant temperature Ts exceeds a predetermined value despite the zone-control, the opening degree of the flow control valve is controlled and increased. By this control, the amount of refrigerant flowing through the cooling bypass increases, and the refrigerant cooling effect on the low pressure side is enhanced.

Abstract: An environmental control system disclosed includes a refrigeration loop including a variable speed compressor having an inlet and an outlet, a condenser having an inlet connected with the compressor outlet and an outlet, and an evaporator having an inlet connected with the condenser outlet and an outlet connected with the compressor inlet. The system also includes a variable speed evaporator fan and evaporator fan control for controlling the speed of the evaporator fan and a monitor for monitoring the superheat condition of the refrigerant at the compressor inlet wherein the evaporator fan control controls the speed of the evaporator fan as a function on the value of the superheat condition. A variable speed condenser fan is controlled by a condenser fan speed control that functions in part on the value of the superheat condition.

Abstract: An environmental control system disclosed includes a refrigeration loop including a variable speed compressor having an inlet and an outlet, a condenser, an evaporator and variable speed evaporator fan for moving air across the evaporator, a compressor speed control, a superheat monitor for monitoring the condition at the inlet of the compressor and a primary superheat control responsive to the superheat monitor for establishing the speed of the evaporator fan to maintain a predetermined superheat condition.

Abstract: In a heat pump system intended for cooling operation at lower ambient conditions, a control is provided for sensing the compressor discharge pressure and for alternately providing power to and removing power from the outdoor fan in response to the discharge pressure respectively exceeding or falling below a predetermined level. Power is provided to and removed from the motor by way of a solid state relay, and the periods in which power is removed are controlled so as to exceed those periods in which the power is applied to the motor. The fan motor is supported by journal bearings, and the periods of time in which power is removed from the motor during the cycling process is limited to 10 seconds such that the motor does not come to a complete stop, thereby ensuring proper lubrication thereto.

Abstract: A self-cleaning heat exchanger (10) has a reversible fan (12) located between two tube banks (14, 16) with a pressure switch (24) connected thereto. The fan (12) rotates in one direction blowing across the first tube bank (14) and drawing air over the second tube bank (16). The pressure switch and fan are interconnected by two relays (28, 30). When the refrigerant pressure in the tube banks exceeds the threshold pressure, the relay (28) is closed and grounded and electric current flows through the relay (30). The change in direction of current flow will reverse the polarity of the windings in motor (13) and thus the rotation of the motor (13) and the fan (12) thereby reversing air flow to remove debris from one tube bank while withdrawing heat from the other without loss of cooling efficiency.

Abstract: Disclosed is an air conditioner and, in particular, an air conditioner which is capable of blowing out warm air in heating mode. In the air conditioner of this invention, the condenser is thermally separated into an air-upstream-side and an air-downstream-side heat exchanger, and the heat exchange capacity of the air-downstream-side heat exchanger is adjusted, so that, under preset operating conditions, the entire refrigerant in the air-downstream-side heat exchanger can be kept in the superheated-gas phase, thus making it possible to blow out warm air having a temperature higher than the condensation temperature. Further, the refrigerant temperature at the outlet of the air-downstream-side heat exchanger is measured by a temperature sensor, and the revolving speed of the compressor, the revolving speed of the fan, etc., is so controlled that the temperature measured is kept at a level higher than the condensation temperature.

Abstract: A cooling apparatus includes a bypass provided to a path extending from a compressor to an expansion valve via a condenser, and a unit for controlling a ratio of a flow rate of a refrigerant of the path via the condenser to that of the bypass path, or a unit for varying an air volume of a fan of an outdoor unit for blowing the condenser so as to vary a capacity of the condenser. The degree of superheat of the refrigerant is measured at an exit of the evaporator, and an expansion valve is controlled in accordance with the measured degree of superheat.

Abstract: The present invention describes a method of controlling the head pressure in a refrigeration or air conditioning system in order to maintain the internal discharge pressure and discharge line pressure substantially equal. The method consists of the steps of measuring the suction pressure of the working fluid, calculating the internal discharge pressure of the working lfuid by multiplying the suction pressure by the internal pressure ratio of the compressor, measuring the discharge line pressure of the working fluid and then comparing the internal discharge pressure to the discharge line pressure. If the difference between the internal discharge pressure and discharge line pressure is greater than some allowable tolerance, the capacity of the condenser is adjusted to equalize these two pressures.

Abstract: A cooling and heating concurrent operation type of multiple refrigeration cycle comprises an indoor unit including a variable delivery type of compressor and an outdoor heat exchanger; indoor units including indoor heat exchangers, respectively; triple connection pipes of a high pressure gas pipe, a high pressure liquid pipe and a low pressure gas pipe, the triple connection pipes connecting between the outdoor unit and the indoor units; pressure detection means for detecting the intake pressure of the compressor and the discharge pressure of the compressor; and calculation and control means for comparing two detected values of the intake pressure and the discharge pressure of the compressor with two set values of a set intake pressure and a set discharge pressure, and for making variable controls of the compression capability of the compressor and the heat exchange capability of the outdoor heat exchanger based on the respective deviation values between the respective detected values and the respective set v

Abstract: A refrigeration cycle comprising a compressor and an outdoor heat exchanger, both of which are arranged outside a room to be air-conditioned, to communicate with an indoor heat exchanger and a radiant heat exchanger, both of which are arranged inside the room, and are operated simultaneously in a heating operation mode. A fan delivers air to the indoor heat exchanger. A temperature sensor detects the temperature of the radiant heat exchanger. A controller controls the indoor heat exchanger fan speed so as to control the radiant heat temperature from the radiant heat exchanger in accordance with a temperature detection signal from the sensor.

Abstract: A vapor cycle cooling system (10) in accordance with the invention includes a compressor (12) for compressing refrigerant vapor; a condenser (14) receiving compressed refrigerant vapor from the compressor; a fan (18) having at least two controllable speeds for blowing a fluid (16) in contact with the condenser to remove heat from the compressed refrigerant at the condenser to cause the refrigerant to liquify, the speeds of the fan being controllable by a control signal; an expansion valve (22) receiving liquid refrigerant from the condenser which expands the liquid refrigerant; an evaporator (24) receiving the expanded refrigerant which exchanges heat with a fluid stream (26) coupled to a heat load (28); and a controller (20) for generating the control signal, responsive to a sensed evaporator temperature, a sensed ambient temperature and a sensed altitude which controls two speeds of the fan as a function of the sensed temperatures and altitude by generating the control signal.

Abstract: A refrigeration control system having a temperature sensor responsive to condenser temperature. The sensor turns a condenser fan on and off in order to maintain the condenser temperature within pre-determined limits and also shuts down the refrigerant compressor in response to a predetermined maximum temperature.

Abstract: A refrigeration system employing a mechanical thermal expansion valve with a self-heated thermistor sensing saturation temperature at the high pressure inlet. A microprocessor based controller compares the sensed temperature with stored limits and provides output signals to a relay for cycling the condenser fan responsive to high side pressure means are provided for varying the current through the thermistor for operating same in the non-self heated mode to sense actual refrigeration temperature for generating a control signal to disable the compressor clutch when refrigerant temperature exceeds desired low limits.

Abstract: In a refrigeration system including a compressor, a condenser exposed to a cooling medium for causing condensation of the refrigerant within the refrigeration system and an apparatus for controlling the flow of the cooling medium, a control method and apparatus for operating the flow control apparatus in response to suction pressure or suction temperature as sensed at the compressor. In an exemplary system utilizing air as the cooling medium and a fan for causing airflow, the fan is started after compressor start-up when sensed suction pressure rises above a predetermined amount. An additional feature includes an adaptive time limited compressor cut-out protection for low ambient temperature operation.

Abstract: A refrigeration system employing a mechanical thermal expansion valve with a self-heated thermistor sensing saturation temperature at a high pressure inlet and a second thermistor sensing saturation temperature at the evaporator outlet. A microprocessor based controller compares the sensed temperature with stored limits and provides output signals to a relay for cycling the condenser fan responsive to high side pressure and the compressor clutch responsive to the low pressure side temperature. For low pressure drop evaporators, the second thermistor may be disposed at the evaporator inlet.

Abstract: An air conditioning apparatus includes an external heat-exchanger having upper and lower side heat-exchanger elements, arranged in a vertical direction, each having a plurality of fluid pipes, upper and lower fan devices disposed opposite to corresponding heat-exchanger elements, and a temperature sensor disposed on one end (discharge side during cooling) of the upper-most fluid pipe of the upper side heat-exchanger element for outputting a detection signal indicating the condensation temperature of the external heat-exchanger corresponding to the condensation pressure of the external heat-exchanger. The rotation speed of the upper side fan device is regulated in accordance with the detection signal from the sensor to control the condensation pressure of the upper and lower side heat-exchanger elements within a prescribed range.

Abstract: A cooling-fan controlling apparatus for an air conditioner system including a variable volume compressor, including a work-performed detecting device for detecting the work performed by the variable volume compressor, a discharge-pressure detecting device for detecting the pressure discharged from said compressor, and a controller for controlling the drive speed of a cooling fan on the basis of both the values detected in said work-performed detecting device and said discharge pressure detecting device.

Abstract: A system for controlling refrigerant flow in an air conditioning system employing an electrically operated valve for controlling flow of refrigerant from the condenser to the evaporator. Separate thermistors sense the temperature of the refrigerant entering and discharging from the evaporator. A comparison of the sensed temperatures is used to modify the control signal to the valve for maintaining proper refrigerant flow to the evaporator.

Abstract: A refrigeration control system for cooling a vehicle passenger compartment having a compressor/pump for circulating refrigerant between an evaporator located for cooling the compartment air and a condenser located for ambient heat exchange. An expansion valve controls refrigerant flow from the condenser to the evaporator; and, a first thermistor senses directly the temperature of the refrigerant on the high pressure inlet side of the valve and a second thermistor senses refrigerant flow temperature on the low pressure discharge side of the valve. A microprocessor compares the first thermistor output with predetermined first upper and lower values and effects opening and closing of the compressor clutch switch for high pressure cut-off; and, a fan switch is opened and closed for energization and de-energization of a condenser cooling fan.

Abstract: Controller apparatus and method for single or multiple heat exchange systems of the type including a working fluid circuit connected to each heat exchanger and with a working fluid in the circuit. In a multiple heat exchange system configuration, a manifold couples together all of the working fluid outputs or inputs from all of the heat exchangers for all of the systems, with an averaging relay for receiving inputs representative of the refrigerant head pressure for the condenser of each heat exchange system and for providing an output from the averaging relay representative of an average of the pressures for all of the systems.

Abstract: An apparatus for recovering waste heat from conventional refrigerating systems in which a heat exchanger is connected between the compressor and condenser to transfer heat to water pumped therethrough. The heated water is stored in a small holding tank and transferred to a larger water storage tank when hot water is withdrawn from the larger tank.

Abstract: Disclosed is a control device having a detector for detecting the degree of superheating or supercooling of refrigerating or air-conditioning units. The detector includes a pressure responsive chamber for guiding the pressure of a coolant and a diaphragm disposed therein. The diaphragm is connected with a temperature-responsive cylinder for sensing the temperature of the coolant and a connecting rod. The connecting rod moves corresponding to the pressure and temperature of the coolant, and the position thereof is sensed by a position sensor means.

Abstract: An outdoor air cooled condenser for a refrigeration installation having at least one refrigeration system circuit and including a condenser coil with a heat transfer surface, a condenser housing having air inlet and outlet means for the passage of air across said heat transfer surface, the outlet means including a primary outlet with air flow control means therefor and a plurality of secondary outlets with air displacement means and damper means associated therewith, sensing means for sensing a predetermined condition of refrigerant in the condenser coil, control circuit means for monitoring and integrating the sensed refrigerant condition with respect to a predetermined ideal condition set point value for the refrigeration system circuit and for operating the air flow control means and air displacement means for controlling the amount of air passing through the housing and across the heat transfer surface.

Abstract: An air-conditioning system for a vehicle is configured so as to adjust draft volume to a condensor for an air conditioner on the basis of the pressure of refrigerant circulated through a condensor and atmospheric temperature to optimize draft volume to be distributed to the condensor and the radiator. The air-conditioning system comprises a plurality of motor-fans for the condensor and the radiator, a refrigerant pressure sensor provided at the input and output of the condensor, an atmospheric temperature sensor, and an operational mode control unit responsive to the refrigerant pressure sensor and to the atmospheric temperature sensor.

Abstract: A variable speed fan drive, operated in response to the sensed coolant temperature in an internal combustion engine for a vehicle, blows a controlled amount of air through the engine's radiator to maintain the coolant temperature in a desired narrow operating range. The air pulled in by the fan also cools the refrigerant flowing through the condenser of the vehicle's air conditioning system, the condenser being positioned in front of the coolant radiator. If insufficient condenser cooling occurs, even though the coolant may be adequately cooled, the refrigerant temperature rises and causes the compressor discharge pressure in the air conditioning system to increase. That pressure is monitored or sensed and if it exceeds a predetermined maximum allowable level the normal operation of the control system is overriden and the fan is driven at its maximum speed to maximize the air blown through the condenser and radiator, thereby decreasing the refrigerant temperature and thus the discharge pressure.

Abstract: A thermally integrated system combining a water heater tank with a refrigeration unit in a manner whereby heat dissipated by the unit serves to heat the water in the tank, the efficiency of the unit being maintained despite changing temperatures in the water tank. In this system, an external line conducting the refrigerant and acting as an auxiliary condenser is extended between the compressor and the main condenser of the refrigerator unit. The external line first passes through the upper region of the tank where it acts in conjunction with a water jacket interposed in the tank outlet pipe as a heat booster, the line then running in a coiled formation through the lower region of the tank in heat exchange relation with the relatively cold incoming water supplied by an inlet pipe.

Abstract: The invention relates to an outdoor air cooled condenser for use in a refrigeration system and a method of controlling the condensing temperature in the condenser. The condenser may be used for one or several closed refrigeration circuits connected thereto. A condenser coil assembly is provided in the condenser and has a condenser coil and a heat transfer surface, the coil being connected to the refrigeration circuit. A housing houses the condenser and has an inlet and an outlet for the passage of air through the housing about the heat transfer surface. The outlet is divided in a primary outlet and a plurality of secondary outlets. A motor-driven fan is provided with each of the outlets. The primary outlet is provided with a controllable damper while the secondary outlets are provided with gravity-operated dampers.

Abstract: A load shaving system for a closed loop cooling system adds a secondary heat exchange unit in shunt in the closed loop system between the output side of the load and the input to the primary heat exchange unit. The secondary heat exchange unit has constant or variable amounts of the return fluid from the load shunted through it in response to the temperature difference between the temperature of the return fluid and the temperature of the cooling medium used in the secondary heat exchange unit, which typically may be a plate and frame heat exchanger or the like. Part or all of the required temperature drop for the fluid in the closed loop system may be obtained from the secondary heat exchanger.