Abstract: An improved refrigerant recovery method and apparatus by which a refrigerant charged in a refrigerator is transferred into a refrigerant tank are disclosed. The apparatus is adapted to discharge almost all the refrigerant gas from the refrigerator and purge non-condensible gases from a safety valve to the atmosphere with little refrigerant gas accompanying the non-condensible gases. There are provided a vacuum pump at the upstream side of a line connected between the refrigerator and a liquid separator, and a compressor at the downstream side thereof, the vacuum pump and compressor being connected in series with each other. The vacuum pump is intended to nearly zero the pressure of the remaining refrigerant gas in the refrigerator and the compressor is to give the liquid separator a desired internal pressure, thereby minimizing the amount of refrigerant gas purged along with the non-condensible gases to the atmosphere. Also a bypass valve is provided to bypass the vacuum pump.

Abstract: In systems or units for collecting volatile liquids, e.g. refrigerants from scrapped refrigeration systems, the liquid may be successively filled into a closed collector tank, inasfar as the vapor of the liquid as collected in the upper space of the tank will be condensed into the liquid as this rises in the tank. However, there will be separated also an amount of non-condensible gas, e.g. atmospheric air, that will cause a steadily increasing pressure in the tank, so that it is necessary to regularly effect a venting of the tank, that is a gas blow-off, by suitably controlling an upper blow-off valve on the tank.

Abstract: A refrigerant reclaim system including an automatic air purge system. The refrigerant reclaim system has an evaporator, oil separator, compressor, condenser, storage tank, and a filter-drier. An improvement relates to an automatic air purge system having an evaporator to concentrate noncondensable gases in an isolated area of the refrigerant reclaim system so as to minimize the loss of refrigerant vapor during purge operations; a differential thermostat and an insulated enclosure are used within the system. The air purge system is not limited to use with a refrigerant reclaim, and is suitable for use with any refrigeration system from which noncondensable gases are to be purged with minimal loss of refrigerant vapor.

Abstract: Apparatus for purification of refrigerant that includes a replaceable filter/dryer unit for removing water from refrigerant passing therethrough and having a predetermined water absorption capacity, and a compressor for pumping refrigerant through the filter/dryer unit. Refrigerant vapor pressure is measured at the compressor inlet, and mass flow rate of water in the refrigerant pumped through the filter/dryer unit is determined as a function of measured pressure. The mass flow rate of water so determined is monitored over time of operation of the refrigerant pump to determine when the mass of water in refrigerant pumped through the filter/dryer unit reaches the predetermined water absorption capacity of the unit. Filter status may be indicated to an operator and/or operation of the pump may be terminated.

Abstract: A portable purging apparatus that automatically removes air and non-condensable gases from an operating refrigeration system wherein refrigerant gas condenses at a cooling coil disposed in the upper portion of a purge vessel, the condensate falling to the bottom of the vessel where a pickup tube conveys the condensate out of the vessel and to a thermal expansion valve that meters refrigerant into the cooling coil, the outlet of the coil connecting to the suction line of the operating refrigeration system. Non-condensable gases collect in the top of the purge vessel and displace condensable gas around the cooling coil causing less heat load at the coil and a lower suction line temperature whereby a thermostat actuates a purging solenoid valve to discharge non-condensable gases from the purge vessel through a flow restricting orfice to the atmosphere.

Abstract: The invention relates to a device for recovering refrigerant, particularly chlorofluorocarbons, from a closed cooling system, comprising a perforator with which a gas-tight connection can be formed with the closed cooling system, a device for separating gaseous components from substances coming from the cooling system, which is characterized by a unit for liquefying the refrigerant and separating gaseous components, particularly air, therefrom.

Abstract: A refrigerant handling system that includes an air purge chamber and a refrigerant pump for directing refrigerant into the air purge chamber so that the refrigerant collects in liquid phase at a lower portion of the chamber while air and other non-condensibles collect in a vapor space at the upper portion of the chamber over the refrigerant. A purge valve is connected to the upper portion of the chamber for automatically or manually purging air and other non-condensibles from the chamber. A refrigerant outlet is positioned at the lower portion of the chamber for drawing liquid phase refrigerant from the chamber. A minimum level of liquid phase refrigerant is maintained in the lower portion of the chamber at the outlet isolating the outlet from the vapor space, and preventing removal of air and other non-condensibles from the chamber through the outlet.

Abstract: A refrigerant recovery and recycling system recovers refrigerant from refrigeration equipment, removing contaminants, for storage and eventual reuse. The system includes a separation unit in which the refrigerant is separated from the contaminants, preferably by distillation which is at least partially driven by waste heat produced by the compressor which compresses the refrigerant for storage.

Abstract: A method and apparatus for reclaiming refrigerant are described to include a bypass line for hot gas is coupled to a distillation liquid temperature control, which controls the temperature of the system to remain at a very low temperature setting in order to prevent moisture carry-over, and maintain an exact liquid level. The distillation chamber itself contains a heat exchange system and comprises an outlet subsystem for distilled refrigerant, as well as an inlet for contaminated refrigerant. Vapor forms above the liquid in the chamber which is discharged into a compressor, which feeds back hot gases through a helical coil arrangement immersed in the distillation chamber. The compressor alternatively bypasses the helical coil under the control of the temperature controller. In either event, either from the bypass or from the coil a small air cooled dispenser dissipates heat from the compressor work.

Abstract: A refrigerant recycling system includes a recycled refrigerant tank for storing recycled refrigerant, and first and second valves connected in series between the recycled refrigerant tank and atmosphere. In purging non-condensables from the recycled refrigerant tank to atmosphere, a programmed microcontroller holds the first valve open for exposing the pressure transducer to the pressure in the recycled refrigerant tank, and opens the second valve when the measured pressure exceeds a predetermined pressure for purging non-condensables to atmosphere, holding the second valve open until the measured pressure drops below the predetermined pressure. The pressure checking and purging steps are repeated after a short period, as often as necessary until the measured pressure is less than or equal to the predetermined pressure while the second valve is closed and then, after a longer delay, the system goes through one more pressure check and, if necessary, purging operation.

Abstract: A bypass filter system for use in low pressure, centrifugal type refrigeration equipment which allows complete isolation of a submicron filter element from the lubrication system through use of an inlet line shut-off and a return line shut-off. The filter system utilizes a variable regulator valve for balancing the operating parameters of the various systems involved to permit initial installation and set up, at which point thereafter the variable regulator may be replaced with a fixed regulator for continued operation of the system. Multiple devices for monitoring the filter element condition, verifying flow, detecting moisture, and displaying pressure readings may be used in conjunction with the basic device to enhance reliability and usefulness.

Abstract: A refrigerant handling system that includes an air purge chamber and a refrigerant pump for directing refrigerant into the air purge chamber so that the refrigerant collects in liquid phase at a lower portion of the chamber while air and other non-condensibles collect in a vapor space at the upper portion of the chamber over the refrigerant. A purge valve is connected to the upper portion of the chamber for automatically or manually purging air and other non-condensibles from the chamber. A refrigerant outlet is positioned at the lower portion of the chamber for drawing liquid phase refrigerant from the chamber. A minimum level of liquid phase refrigerant is maintained in the lower portion of the chamber at the outlet isolating the outlet from the vapor space, and preventing removal of air and other non-condensibles from the chamber through the outlet.

Abstract: A portable refrigerant recovery and recycling apparatus and method for removing and recycling chloroflourocarbon (CFC), hydroflourocarbon (HFC) and hydrochloroflourocarbon (HCFC) refrigerants from refrigeration systems through a closed loop connection which prevents the release of refrigerant to the atmosphere. A refrigerant is drawn by suction through a filter in its liquid state and transferred to a storage tank. When all liquid refrigerant has been so transferred, a refrigerant vapor recovery process automatically engages and retrieves and condenses the remaining refrigerant vapors, thus completing evacuation of the closed loop refrigeration system until the refrigeration system is evacuated to a pressure of approximately 29 inches Hg absolute for low pressure refrigeration systemes and 20 inches Hg absolute for high pressure refrigeration systems, at which time the present invention automatically shuts off.

Abstract: The presence of an undesirable quantity of noncondensible gases in a refrigeration unit is inferred as a function of both the vapor pressure and temperature at a selected point in the refrigeration unit where the noncondensible gases tend to gather. Purging of these noncondensible gases, which contaminate the refrigerant, is responsive to a comparison in a programmable controller of the actual vapor pressure measured at the selected point, and the known pressure of uncontaminated refrigerant at the temperature existing at the selected point. On detecting a difference between these pressures that is greater than a desired value, the controller calculates a control output signal needed to purge a volume of contaminated vapor from the unit that is effective for reducing the difference between the measured pressure of contaminated refrigerant and the known pressure of uncontaminated refrigerant to a desired value.

Abstract: A monitor used in refrigerant recovery systems to detect and reduce non-condensable vapor in a storage container. The monitor has a sampling reservoir that draws a sample of liquid refrigerant contained in a storage container. The sample of liquid refrigerant is allowed to reach equilibrium, providing a saturated vapor pressure, which is compared to the vapor pressure in an upper portion of the container. The difference in pressure between the sampling reservoir and the container indicating when the container should be exhausted.

Abstract: A refrigerant recovery machine which includes a distiller, oil separator, filters and an air separator to purify and reclaim refrigerant gas from a cooling system. The air separator may include a dual pressure gauge to regulate partial pressures of air and refrigerant to prevent the refrigerant from being vented to the atmosphere.

Abstract: Provided is a purge apparatus for removing foreign non-condensable gases from a refrigeration system. The purge apparatus includes a closed purge chamber adapted to receive foreign gases together with a portion of the refrigerant from the high pressure region of the refrigeration system. The purge chamber is cooled to condense the refrigerant. During a Purge Mode, the purge chamber is isolated from the refrigeration system, and gases and a portion of the refrigerant in the purge chamber are vented to a gas separation tank. Adsorbent material in the gas separation tank adsorbs refrigerant and the other gasses are vented from the gas separation tank to the atmosphere. During a Quiet Mode, condensed refrigerant is drawn from the purge chamber to the low pressure portion of the refrigerant system, and a vacuum is drawn on the gas separation tank and the gas separation tank is heated to draw refrigerant from the adsorbent material.

Abstract: A thermal purge system includes a purge vessel into which is introduced hot gaseous refrigerant fluid from the outlet of a conventional chiller. A first coil having very cold refrigerant fluid flowing through it is positioned within the vessel so that much of the hot gaseous refrigerant fluid from the chiller is condensed upon contact with the coil. The condensate collects on the bottom of the vessel until it reaches a depth sufficient to initiate a syphoning action by an artesian well which returns the condensate to the chiller. Uncondensed gases are reheated and re-expanded external to the vessel and returned to the vessel through a second coil in heat transfer relation to the first coil so that further condensation occurs. Noncondensibles which remain after the reheating, re-expansion, and recooling are purged to the atmosphere.

Abstract: A refrigerant reclaim system including an automatic air purge system. The refrigerant reclaim system has an evaporator, oil separator, compressor, condenser, storage tank, and a filter-drier. An improvement relates to an automatic air purge system having an evaporator to concentrate noncondensable gases in an isolated area of the refrigerant reclaim system so as to minimize the loss of refrigerant vapor during purge operations. The air purge system is not limited to use with a refrigerant reclaim, and is suitable for use with any refrigeration system from which noncondensable gases are to be purged with minimal loss of refrigerant vapor.

Abstract: A refrigerant handling system that includes a closed vessel for storing refrigerant and an apparatus for determining quantity of air captured within the vessel. A first sensor is operatively coupled to the vessel for providing a first electrical signal as a function of air/refrigerant vapor pressure within the vessel, and a second sensor is operatively coupled to the vessel for providing a second electrical signal as a function of air/refrigerant vapor temperature within the vessel. A microprocessor-based controller has internal memory in which electronic indicia is stored for relating saturation pressure to temperature for multiple types of refrigerant. This stored electronic indicia is employed in conjunction with the first and second sensor signals to determine quantity of air within the vessel as a function of a difference between pressure indicated by the first sensor signal and the saturation pressure indicia at the temperature indicated by the second sensor signal.

Abstract: An auxiliary purge unit to be retrofitted to the existing purge unit of a low pressure refrigeration system includes a double-walled condenser portion, a pneumatic pressure chamber and a discharged-refrigerant tank. The double-walled condenser portion includes inner and outer walls with a chilled condensing coil disposed between the two walls, a stand pipe to create a reservoir of condensed refrigerant between the stand pipe and the inner wall, and an exhaust port for exhausting non-condensibles from the system. The pneumatic pressure chamber pressurizes the gas to be purged from the refrigeration system and delivers it to the chilled condensing coil. The discharged-refrigerant tank includes a float valve to prevent fluids from exiting the tank unless the valve is in the open position, and allows the elevated pressure of the system to be maintained.

Abstract: Apparatus for purification of a single refrigerant type, or of differing refrigerant types having differing density and moisture solubility characteristics, that includes a filter/drier unit for removing water from refrigerant passing therethrough and having a predetermined water absorption capacity. A refrigerant pump, such as a refrigerant compressor, pumps refrigerant through the filter/drier unit during recovery of refrigerant from equipment under service and/or in a separate refrigerant purification cycle. A flow meter is coupled to the filer/drier unit for measuring volumetric flow of refrigerant passing through the filter/drier unit. Volumetric flow of refrigerant through the flow meter is monitored over time for indicating to an operator when the filter/drier unit should be replaced as a function of mass of refrigerant pumped through the filter/drier unit and independent of types of refrigerant pumped through the filter/drier unit.

Abstract: A refrigerant recovery and purification system that includes a refrigerant compressor having an inlet for connection to refrigeration equipment under service from which refrigerant is to be recovered. The outlet of the compressor is connected through a condenser to a refrigerant storage vessel or container, with the condenser at least partially liquifying refrigerant prior to passage to the storage container. A liquid refrigerant pump is connected for selectively circulating refrigerant in liquid phase in a closed path from the storage container through a filter for removing contaminants from the refrigerant, and then through the condenser back to the storage container. Refrigerant circulated by the liquid pump in the closed path is thus simultaneously purified by passage through the filter and cooled by passage through the condenser.

Abstract: Provision is made in a refrigeration purge system for sensing certain conditions indicative of failure of components within the system, to responsively shut-down the system and prevent refrigerant from being undesirably vented to the atmosphere. Failure conditions sensed include inadequate cooling medium to the condenser coil and failure of a relief valve.

Abstract: A refrigerant handling system that includes a liquid refrigerant storage container and a pump for feeding refrigerant in liquid phase to the container so that any air in the container or carried by the circulating refrigerant is captured within the container over the refrigerant. A bulb containing a reference refrigerant (R12) is positioned in heat transfer relation with refrigerant fed to the container. A pressure gauge is coupled to the bulb and calibrated to indicate saturation temperature of the reference refrigerant, and thereby reflect actual temperature of refrigerant in the container. A differential pressure gauge has separate scales for multiple refrigerant types (R22, R134a, R500, R502) to indicate apparent refrigerant temperature as a function of any bulb/container pressure differential. A valve is coupled to the container for venting air therefrom when apparent refrigerant temperature exceeds actual refrigerant temperature for the specific refrigerant type under service.

Abstract: A refrigerant purification and recovery apparatus for removing refrigerant from a refrigeration unit includes a compressor, condenser and receiver vessel. Second and third conduits conduct refrigerant flow from the compressor to the condenser and from the condenser to the receiver vessel, respectively. An auxiliary condenser valve may be opened and closed to selectively block flow through the third conduit, and first and second connectors for making fluid communicating connections with the third conduit are located upstream and downstream of the valve, respectively. An auxiliary condenser may be releasably connected to the first and second connectors, and the valve closed, to cause fluid flowing through the third conduit to flow through the auxiliary condenser. The apparatus may include a temperature measurement and signaling device to signal when the temperature of the third conduit is above a predetermined temperature.

Abstract: A refrigerant purification and recovery apparatus for removing refrigerant from a refrigeration unit and for purifying the refrigerant removed from the refrigeration unit includes a compressor, condenser, a receiver-separator vessel having upper and lower end portions, pressure detection means for generating signals indicative of a pressure in the upper end portion of the receiver-separator vessel, liquid detection means for generating a signal indicative of the presence or absence of liquid in the vessel at a position between the upper and lower end portions, means for venting gas from the upper end portion of the receiver-separator vessel, means for draining liquid from the lower end portion of the receiver-separator vessel, and control-signal means for receiving the pressure indicative and liquid-presence indicative signals and generating a drain signal only when the pressure indicative signal is indicative of a pressure greater than a predetermined pressure and the liquid presence indicative signal is ind

Abstract: An automatic purger for an absorption heat pump has a generator, a condensor, an evaporator and an absorber. The purger includes an eductor connected to the absorber, a purging chamber connected to the absorber and mounting therein a nozzle, a heat-dissipating tube connected between the educator and the nozzle, a storage tank communicating with the absorber and mounting thereto a solution level controller, a diffuser for increasing the pressure of the absorbing agent solution ejected from the nozzle into the storage tank, and a vacuum pump connected to the storage tank. Due to a low pressure zone formed around the exit of the nozzle in the purging chamber, non-condensable gas existing in the absorber will be extracted into the purging chamber and then be carried into the storage tank by the absorbing agent solution ejected from the nozzle.

Abstract: A refrigerant handling system in accordance with the present invention includes a closed liquid refrigerant storage container and a pump for feeding refrigerant in liquid phase to the container so that any air carried by the circulating refrigerant is captured in the container over the refrigerant. A differential pressure gauge has a first input that receives a fluid pressure signal which varies as a function of saturation pressure of refrigerant in liquid phase fed to the container, and a second input that receives an associated fluid pressure signal as a function of air pressure within the closed container volume. An indicator dial on the gauge displays pressure differential between the refrigerant saturation pressure and the container vapor pressure at the first and second gauge inputs for observation by an operator. A valve is coupled to the container for venting air from the container when such pressure differential exceeds a preselected threshold.

Abstract: A cryogenic refrigeration system has a control system that controls the operation of the refrigeration system and provides status information to the operator of the refrigeration system. The cryogenic refrigeration system includes one or more heater and at least one Joule-Thomson valve. The heaters are used to control the recondensing capacity of the refrigeration system and to heat the at least one Joule-Thomson valve and other points to melt away contaminants that may freeze at such points. The control system controls operation of the heaters. The control system also automates an initialization routine that utilizes the heaters to prevent blockage of the valves, and cools the refrigeration system down to a desired temperature. In addition, the control system shuts down the refrigeration system if the status information it monitors exceed a safe range.

Abstract: A system for purification of refrigerant within a storage container includes a filter/dryer for removing contaminants' from refrigerant passing therethrough, and a refrigerant pump connected to the storage container to circulate refrigerant in a closed path from the container through the filter/dryer and return the refrigerant to the container. The system configuration is such that the refrigerant is in liquid phase in at least a portion of the closed path. A pressure-differential valve has an inlet coupled to a purge port on the container for receiving air captured within the container. Container air pressure at the valve inlet is fed to one side of a flexible diaphragm. Circulating liquid refrigerant is passed in heat transfer contact with a sealed enclosure containing liquid refrigerant, so that the refrigerant within the enclosure is at saturation pressure and acts on the opposing side of the diaphragm in conjunction with a valve spring.

Abstract: A refrigerant recovery system has a refrigerant recovery vessel which is connected to a refrigerant-recovered refrigeration circuit. A gaseous refrigerant in the refrigerant-recovered refrigeration system is sucked into the refrigerant recovery vessel due to the difference between the pressure in the refrigerant-recovered refrigeration circuit and the refrigerant recovery wheel. The refrigerant recovery vessel is cooled by a refrigeration circuit provided in the refrigerant recovery system, so that the sucked gaseous refrigerant is a liquified. to the refrigerant recovery vessel, a recovery tank made of a cartridge type is connected. The liquefied refrigerant from the refrigerant recovery vessel is sent to the tank. When the temperature of the recovery tank is not low enough, the liquefied refrigerant sent into the tank is evaporated and then returns to the refrigerant recovery vessel so that the refrigerant is liquefied in the vessel again.

Abstract: For carrying out charging of a refrigerant into a storage container (26), the refrigerant is separated into gaseous and liquid phase refrigerant segments which are supplied to a receiving unit (22) and an evaporator (18), respectively. The receiving unit and the evaporator are thermally coupled to each other. The gaseous phase refrigerant segment is modified into a modified refrigerant in a liquid phase in the receiving unit by use of evaporation of the liquid phase refrigerant segment in the evaporator. The modified refrigerant is sent from the receiving unit to the storage container. For smoothly carrying out reception of the modified refrigerant in the storage container, the inner pressure of storage container is controlled by a controlling arrangement (31, 32, 33, 34).

Abstract: This valve (12) for sensing and purging non-condensible gases in a refrigerant includes a valve body (30) having a lower refrigerant inlet (32), an upper exhaust outlet (36) and a valve passage (44) therebetween controlled by a valve element (54) extending between a spring (72) and a diaphragm (86). A housing (100) containing a "pure" refrigerant charge and a spring (110) are provided at the other side of the diaphragm (86) and the housing (100) is exposed to temperature of the system refrigerant. One side of the diaphragm (86) is subjected to the combined pressure of the spring (72) and the pressure of the system refrigerant at the inlet (32) and the other side of the diaphragm (86) is subjected to the balancing pressure provided by the combined pressure of the refrigerant charge and the spring (110). The valve (12) opens in response to increased pressure of the system refrigerant at the inlet (32) resulting from the presence of non-condensible gases and exhausts the gases to atmosphere.

Abstract: An air conditioner charging station withdraws refrigerant from an air conditioner, reclaims it by removing certain materials, and returns the reclaimed refrigerant to the same air conditioner from which it was withdrawn, and also provides new, make-up refrigerant to the air conditioner, in the amount necessary to make a full charge. A microprocessor provides a diagnostic capability, and includes tables of acceptable values of parameters, such as air discharge temperature, suction pressure, etc., for different automobile makes and air conditioner types; provision is made for adjusting the acceptable ranges of such values due to one or more ambient factors, of which ambient relative humidity may be one. The microprocessor, after comparing actual values to acceptable value ranges of the air conditioner operating values, displays possible causes of air conditioner malfunction on a video screen.

Abstract: A system for refrigerant and recovery and processing includes a hollow fluid-tight pressure vessel having a fluid input; a hollow annular jacket having its inner surface in thermal communication with the pressure vessel, the jacket having a polar axis in substantial alignment with the gravity vector, and the jacket having a liquid accumulator at the bottom thereof. The jacket is provided with an input in liquid communication with the refrigeration system to be vented during a recovery process, such input line in fluid communication with the pressure vessel during reprocessing of the refrigerant. The input from the refrigerant line is further provided with a liquid expansion element for selectively increasing the volume of fluid flowing from the vessel, or from the refrigerant system to be vented. A condenser is in fluid communication with the output of the pressure vessel.

Abstract: An auger-type ice making machine has a refrigerating cylinder having upper and lower bearings, an auger supported rotatably within the refrigerating cylinder by the upper and lower bearings, a water supply valve for supplying water to the refrigerating cylinder, a drain valve in fluid communication with the refrigerating cylinder for discharging water therefrom, an electric detector assembly including an electrode member having its one end extending into the refrigerating cylinder, and an electric control circuit electrically connected to the electrode member to receive a detection signal from the electric detector assembly. The electric control circuit determines on the basis of the detection signal that the impurity concentration of the water has increased beyond a predetermined level.

Abstract: Method and apparatus of discharging non-condensable gases from the circuit of a compression refrigeration machine, wherein a part of the circuit through which there is no flow is indirectly cooled by a smaller secondary refrigeration machine in order to condense the condensable refrigerant vapor in that part and thus to lower the content of non-condensable gases to be discharged in that part, whereby the value of the suction pressure of the refrigerant circuit of the secondary refrigerating machine is used for automatically starting and stopping the discharge of non-condensable gases.

Abstract: A method for determining the amount of dissolved oxygen in the aqueous medium from a steam generator system that results from air leakage into the system above the water level in a condensor hotwell and that which results from air leakage below the water level in the condensor. Intentional injection of air above water level and intentional injection of air below water level are effected and resultant dissolved oxygen contents measured. The air leakage rate and dissolved oxygen contents at steady state operation are also measured. From these measurements, the amount of dissolved oxygen resulting from above and below water level are determined mathematically or graphically.

Abstract: A refrigeration system is disclosed having a purge system with means for monitoring operation of the purge system and for taking corrective action in response to excessive purge system operation. Preferably, the monitoring means is a microcomputer control system for monitoring purge pump operation to determine if the purge pump has operated continuously for a period of time greater than a predetermined amount of time. If the purge pump has operated continuously for a period of time greater than the predetermined amount of time, then the microcomputer control system overrides normal purge pump operation and maintains the purge pump inoperative for a selected time period before attempting to resume normal operation. The microcomputer control system counts the number of consecutive times that normal purge pump operation is overridden and totally disables the purge system if the number of consecutive overrides exceeds a preselected number.

Abstract: A method for maintaining a preselected concentration of non-condensible gases in a condenser is disclosed. A compressor supplies the condenser with compressed ammonia. The compressed ammonia includes non-condensible gases. At least a portion of the compressed ammonia condenses, forms condensed ammonia and exits the condenser. A pressure controller operates an automatic valve to vent at least a portion of the non-condensible gases from the condenser. A temperature element senses the condensed ammonia temperature and sends a signal, based upon the condensed ammonia temperature, to the pressure controller. The pressure controller uses the signal to reduce the pressure of the condenser from a predetermined value to a computed value estimated to be necessary to maintain the preselected concentration of non-condensible gases in the condenser.

Abstract: A refrigeration purging system for the removal of non-condensible gases such as air and condensible contaminants such as water is disclosed. A portion of the refrigerant in the refrigeration system is placed in a first purge chamber which condenses the refrigerant and condensible contaminants such as water leaving non-condensibles such as air and a small portion of the refrigerant at the top of the chamber. The non-condensibles and remaining refrigerant is extracted from the first chamber pumped to a higher pressure and passed to a second purged chamber wherein the remaining refrigerant is condensed and returned to the first purged chamber. The non-condensible gases remaining are released to the atmosphere. The condensible contaminants are extracted from the first purged chamber and the condensed refrigerant is returned to the refrigeration system.

Abstract: A purge system for use in a refrigeration system utilizing more than one condenser, each of which operates at different pressures. The purge system includes a purge chamber having a cooling coil connected to the evaporator and adapted to condense refrigerant vapor. The purge chamber is connected to a main purge refrigerant line which includes a pressure reducing device. Either condenser in the refrigeration system is provided with a secondary purge refrigerant line connected to the main purge refrigerant line and having a one-way valve to prevent refrigerant flow from one condenser to another condenser. A pump is mounted in the system to remove the non-condensibles from the purge system. The pump is operatively connected to a pressure switch arranged between two sampling pressure lines, one of which is extending to the purge chamber and another one is extending to the main purge refrigerant line at a point ahead of the pressure reducing device.

Abstract: Flow control for a cryostat in which the refrigerant flow rate is controlled by adding a contaminant to the refrigerant.