Abstract: The present invention relates to a refrigerant recycling and reclaiming system capable of removing refrigerant from a refrigeration machine for filtering and reclaiming of the refrigerant, whereupon the refrigerant can be either stored or reintroduced into the refrigeration machine and reused rather than being lost to the atmosphere or otherwise wasted. The recycling and reclaiming system of the present invention is characterized in that it includes an evaporator and/or refrigerant storage tank which are contained within a thermal barrier, typically a water bath, which permits the system to operate at lower temperatures and pressures than systems heretofore known in the art. Lower temperatures and pressures in turn require a much smaller horsepower compressor unit resulting in a decrease in the physical size and operating cost of the system.

Abstract: A refrigerant recovery system that includes a compressor having an inlet and an outlet, and an oil separator connected to the compressor inlet for separating oil from refrigerant recovered from equipment under service. A check valve is connected between a vapor outlet port on the oil separator and the inlet of the compressor for feeding refrigerant directly to the compressor inlet. A pressure sensor is connected to the oil separator for indicating refrigerant vapor pressure within the separator, and a valve is automatically responsive to such refrigerant vapor pressure for connecting a vacuum pump between the oil separator vapor port and the compressor inlet in parallel with the check valve when refrigerant vapor pressure at the oil separator falls below a predetermined value.

Abstract: A refrigerant charge receptacle (25) is provided for interfacing between an air conditioning system (2) having a high-pressure pipe (241) and a low-pressure pipe (242) and a refrigerant charge apparatus, having a high-pressure charge valve (332a) and a low-pressure charge valve (332b), for charging the air conditioning system (2) with a refrigerant. The refrigerant charge receptacle (25) includes a receptacle block (251) having disposed within a high-pressure bore (251a) having the high-pressure pipe (241) attached thereto and a high-pressure opening (105b). Also disposed within the receptacle block (251) is a low-pressure bore (251b) having the low-pressure pipe (242) attached thereto and a low-pressure opening (106b). A high-pressure receptacle valve (252) is attached to the high-pressure opening (105b) for mating with and receiving a first flow of the refrigerant from the high-pressure charge valve (332a).

Abstract: Apparatus and method for operating the apparatus is disclosed for transferring reclaimed refrigerant from multiple recovery cylinders to a larger shipping cylinder using a vapor compressor and four-way valve to first transfer liquid refrigerant and then vapor to the shipping cylinder. This system includes flexible hoses for liquid and vapor transfer and employs valves near the couplings for connections of the hoses to the cylinders. Operating methods then permit transfer from successive cylinders to the shipping cylinders and change-outs in the shipping cylinders without loss of significant refrigerant to the atmosphere, and without inclusion of air into the refrigerant in the shipping cylinder.

Abstract: An apparatus and method for controlling the charging of refrigerant into a refrigerant system is disclosed. The apparatus determines the mass amount of refrigerant charged by determining the volume of refrigerant charged, the density of the refrigerant based on its pressure as it is charged, and determines the mass amount charged from the determined density and pressure. The apparatus has a pressure compensated flow valve and determines the volume of refrigerant charged based on the amount of time refrigerant has flowed through the constant flow valve. The type of refrigerant being charged can be selected from a plurality of refrigerant types and the apparatus has a memory in which data related to density and flow characteristics of each refrigerant type is stored. The apparatus uses the data for the selected refrigerant to determine the mass amount of refrigerant charged. The apparatus further determines that the refrigerant supply tank is empty when its pressure decay exceeds a predetermined amount.

Abstract: A portable refrigerant recycle unit is disposed adjacent to a recycle (reclamation) unit for receiving excess or waste heat discharged therefrom. Liquid and gas refrigerant (e.g., freon) flow from the unit being evacuated to a heat exchanger. A fan draws discharged heat from the reclamation unit across the fins of the heat exchanger. Liquid freon flowing through the heat exchanger is vaporized as it is heated by the air drawn by the fan containing the heat discharged from unit. Gaseous freon flows from the heat exchanger to an oil seperator. Freon vapor then flows from the oil seperator through a filter to the recycle unit output. The reclamation unit condenses the recycle unit output of vapor freon to a liquid. The liquid freon flows from the output of the reclamation to a refrigerant receiver.

Abstract: An oil collector unit of a refrigerant recovery system includes a housing, an interior middle vertical wall disposed in the housing, an interior middle horizontal wall disposed in the housing and intersecting the interior vertical wall and defining left and right pairs of upper and lower chambers on opposite sides of the middle vertical wall having passageways between the upper and lower chambers at opposite ends of the middle horizontal wall which are spaced from the opposite ends of the housing, and a plurality of tubes connected in flow communication with selected ones of the chambers of the housing so as to define a circuitous flow path through the chambers of the housing permitting travel of a fluid mixture of refrigerant and oil therethrough and separation of oil from refrigerant therewithin.

Abstract: Refrigerant is recovered using a single pump unit, regardless of the refrigerant's phase. This is achieved by sensing the phase of the refrigerant and changing the pump's operation accordingly. The refrigerant phase can be sensed by a temperature-responsive element, such as a thermistor, or by other phase-sensing technology. In a preferred embodiment, the pump unit is a vane pump whose rotational speed is changed in response to the refrigerant's phase. If liquid refrigerant is sensed,, the pump operates at a lower speed. If gas refrigerant is sensed, the pump operates at a higher speed. The two speeds are chosen so that the pump will draw an EPA-specified vacuum on the refrigerant present. In other vane-pump embodiments, the pump's operation is changed by changing rotational speed.

Abstract: An apparatus is disclosed for the recovery, separation and recycling of refrigerant from a number of refrigerant chiller systems having individual low efficiency purgers. The apparatus has a high efficiency purger which reduces refrigerant contaminants in the non-condensable gases vented to atmosphere by 90 percent over that of the low efficiency purgers, and operates without interference with the normal purging cycles of the chillers. The apparatus further comprises conduits, valves and a pump which enables the apparatus to completely evacuate the refrigerant gas and refrigerant liquid from the chiller systems.

Abstract: A manually operated refrigerant recovery device is disclosed that includes a piston/cylinder pump combination, wherein the piston defines opposing fluid chambers in the cylinder. A handle is attached via a connecting rod to the piston. First and second one-way check valves are provided at the pump inlet and outlet to ensure that fluid flows in only one direction through the pump. A pressure relief valve is in fluid communication with the fluid chamber opposite the pump chamber and is continuously manually adjustable between an open position and a closed position. The pressure relief valve is closed upon initial pressurization of the pump to dampen sudden upward movement of the handle and is open during pumping to facilitate manual pumping. In another embodiment, a manually operated refrigerant recovery device is disclosed which includes a piston/cylinder pump combination, wherein the piston defines opposing fluid chambers in the cylinder.

Abstract: Apparatus for identifying and distinguishing between at least two types of refrigerant that includes a fixed volume for containing a refrigerant sample at controlled vapor pressure. A thermistor provides a first electrical signal as a function of the combined effect of thermal conductivity and temperature of a refrigerant sample in the sample-containing volume, and a temperature sensor provides a second electrical signal as a function of temperature of the refrigerant vapor in the sample-containing volume essentially independent of thermal conductivity thereof. Associated electronics determines type of refrigerant in the sample-containing volume as a function of the first and second electrical signals, and thus as a function of thermal conductivity of the refrigerant sample independent of sample temperature. Since thermal conductivity of refrigerants at a given temperature and pressure varies for different refrigerant types, refrigerant type can be determined and displayed to an operator.

Abstract: Portable, hand carryable acid purification and flushing and transfer systems are provided for use in various refrigerant recovery, recycling and flushing operations performed in conjunction with an air conditioning circuit. The acid purification system is disposed within a carrying housing and includes an accumulation/distillation type acid separator piped in series with a pair of cylindrical dual core filter assemblies. A pair of refrigerant inlet and outlet fittings are externally mounted on the housing. By connecting these fittings in a forced flow refrigerant circuit the refrigerant is passed sequentially through the acid separator and the first and second filter assemblies to cleanse the refrigerant of acid and particulate impurities therein. The portable flushing and transfer system is also disposed in a carrying housing and includes a high capacity liquid refrigerant transfer pump piped in series with a check valve and a relief valve.

Abstract: There is disclosed herein a refrigerant container in the form of a bag, or pouch, made from two sheets of multi-layer barrier film material which are heat sealed adjacent their edges to form a closed pouch which has an interior space. The bag may be connected to an access valve provided in a line of a sealed refrigeration system for capturing the refrigerant therefrom. The barrier film material is specially formulated to prevent outward permeation of a refrigerant and to prevent inward permeation of air. A valve system is provided for filling and emptying the bag.

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 recovery device is provided with a pressure sensing means, liquid sensing means, fluid flow measuring means, telephone dialer for dialing a telephone number, telephone signaler for transmitting a signal over a telephone line to a telephone communication device, and a controller for receiving a parameter value indicative signal indictive of pressure liquid or fluid flow in a predetermined range causing the telephone dialer to dial a telephone number and establish telephone communicaton with the telephone communicaton device and transmit a signal, indicative of pressure liquid or fluid flow, to the telephone communication device.

Abstract: A hand-transportable unit for transferring refrigerants between containers includes a pump to remove refrigerant from a first container The pump is driven by a pneumatic motor. The pump is capable of transferring refrigerant in liquid form, vapor form, or simultaneously in both forms. A condenser for cooling refrigerant is in fluid communication with the pump. The unit also includes a compressor for driving the pneumatic motor to operate the pump. Optionally, the pump may be powered from an external source of compressed gas. The other components of the unit are mounted to a handcart including a frame and wheels to facilitate movement of the unit. In a preferred embodiment, unit is configured for self-evacuation by use of the pump in order to avoid cross-contamination of different refrigerants during subsequent use of the unit.

Abstract: Apparatus for recovering and recycling refrigerant fluid includes an external or open drive compressor having a suction side and a discharge side, an inlet port for receiving refrigerant fluid from a refrigeration unit, a suction conduit communicating between the inlet port and the suction side of the compressor, an outlet port for expelling refrigerant fluid from the apparatus and a discharge conduit communicating between the discharge side of the compressor and the outlet port. The apparatus further includes a filter for filtering moisture and other contaminants from the incoming refrigerant and an evaporator for substantially completely vaporizing the incoming refrigerant before it reaches the suction side of the compressor. The apparatus does not include a dedicated condenser, but rather the refrigerant discharged by the compressor is condensed in a series of heat exchange processes, whereby the warmer refrigerant discharged from the compressor gives up heat to the cooler incoming refrigerant.

Abstract: A self contained mobile refrigerant recovery and purification system in which refrigerant is withdrawn through a filter/dryer in liquid or vapor phase and then to a holding tank through a heat exchanger located within the tank. The flow of the recovered refrigerant through the heat exchanger is utilized to regulate the pressure within the tank, reducing the pressure to effect withdrawal and elevating the pressure to effect recharging of the serviced refrigeration system. After refrigerant withdrawal is complete, liquid refrigerant within the holding tank is cycled from the holding tank through the filter/dryer and back to the holding tank. The reclaimed refrigerant can then be transferred back to the serviced system in either liquid or vapor form as desired. Between recovery jobs the recovery system can be cleansed out by cycling a cleansed and pumped out by cycling a clean refrigerant through the filter/dryer and the holding tank.

Abstract: A refrigerant tube piercing tool capable of being removably and sealingly mounted on a refrigerant tube of copper or the like in a sealed refrigerant system to enable the recovery of refrigerant from the sealed system without discharge into the atmosphere. The tool includes a pair of clamp members one of which includes a sealing member and passageway combined with a threaded, pointed piercing member that is manually threaded into engagement with the tube for forming a hole therein and a fitting having a Schrader valve incorporated therein to which a hose leading to a recovery tank can be connected to enable refrigerant to be transferred into the recovery tank for subsequent use. The tool is reusable and can be removed after the refrigerant has been transferred into the recovery tank in order that the leak or other problem with respect to the refrigerant system can be repaired at which time the hole formed in the tube is closed by soldering or the like with the refrigerant system then being recharged.

Abstract: A portable, refrigerant recycle/recovery/charging system comprising: a storage tank; a low pressure refrigeration system; and a housing. The housing includes liquid, vapor, pump and condenser sections. The liquid section has a liquid inlet, a liquid outlet and a liquid conduit connecting the liquid inlet and the liquid outlet where the liquid conduit includes a liquid flow control device and a liquid condition sensing device. The vapor section has a vapor inlet, a vapor outlet, and a vapor conduit connecting the vapor inlet and the vapor outlet where the vapor conduit includes a vapor flow control device and a vapor condition sensing device. The pump section has a pump inlet, a pump outlet, and a pump conduit connecting the pump inlet and the pump outlet where the pump conduit includes a pump. The condensing section has a condensing inlet, a condensing outlet, and a condensing conduit connecting the condensing inlet and the condensing outlet where the condensing conduit includes a condenser.

Abstract: A refrigerant recovery unit for large refrigerant systems has a suction compressor which withdraws vapor and a liquid pump which withdraws liquid refrigerant. The compressor and liquid pump pass the fluids to a heat exchanger and a condenser, both located within a bath of chilled liquid. The vapor condenses into a liquid and combines with the liquid refrigerant. The liquid passes to a storage tank. A feedback compressor withdraws vapor from the upper portion of the tank if the pressure is above a selected level and passes it to the condenser for further condensation. A bypass line directs refrigerant vapor to the inlet of the feedback compressor if the tank vapor pressure is below the selected level. A drawdown line allows the feedback compressor to draw all of the refrigerant from the recovery unit after the recovery unit has recovered the refrigerant from the refrigeration system.

Abstract: In order to separate a mixture of two gaseous components with different boiling temperatures, it is proposed that the mixture be initially compressed and thereupon cooled so that its temperature lies below the boiling temperature of the gas components to be removed. The gas components to be removed undergo condensation and can be led off for reutilization without contaminating the environment. Furthermore, it is proposed to feed the gas mixture through activated carbon filters (4, 5) after the condensation process, in order to bind remaining proportions of the gas components to be removed. It is also intended to partially return the gas mixture for renewed liquefaction after it has passed through said activated carbon filters. At the same time, the invention proposes a suitable installation for the execution of this process.

Abstract: A regulator for controlling the flow of refrigerant in a refrigerant reclaiming system having a compressor and a condenser, the regulator comprising a condenser regulator section through which the flow of refrigerant passes after exiting the condenser. The condenser regulator section includes a hollow cylindrical container with an inlet port in the top for receiving the flow of refrigerant, and a hollow tube mounted in the top of the container which extends vertically to the vicinity of the bottom of the container, for releasing refrigerant from the container. A liquid float valve mounted in the lower end of the tube opens the release tube only when liquid refrigerant is present. The regulator may further comprise a compressor regulator section through which the flow of refrigerant passes before entering the compressor.

Abstract: A temperature control chamber is designed for use with refrigerant recovery systems. The temperature control chamber comprises a main base portion, in the form of an upright container, with an open top. A refrigerant storage tank is placed in the container, which has dimensions such that the handle on the top of the storage tank extends beyond the top of the sides of the main base portion of the container. A rigid cover, with an aperture in its center, fits down over the open end of the main base portion; and the handle of the refrigerant storage tank extends through the aperture. A plurality of releaseable latches then secure the cover to the main base portion; so that when the refrigerant tank within the temperature control chamber is lifted and moved from place to place by means of its handle, the temperature control chamber also is lifted by the interaction of the top of the tank with the cover pressing downwardly on the top of the tank.

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 halogenated hydrocarbon recycling machine M1 comprising a cylinder-emptying apparatus including means for transferring a vapour mixture from a cylinder 10 to a fluid storage reservoir R1, a cylinder-filling apparatus including means for filling the cylinder 10.sup.1 from the reservoir R1 and a fluid separating apparatus including means for separating from the vapour mixture of an emptied cylinder, a reusable halogenated hydrocarbon fluid for use by the cylinder filling apparatus.

Abstract: A refrigerant handling system that includes a compressor and an evaporator for adding heat to refrigerant fed to the compressor inlet. A first condenser is connected to the compressor outlet and disposed in heat exchange relationship to the evaporator for at least partially condensing refrigerant vapor from the compressor outlet by transfer of heat to refrigerant in the evaporator. A second condenser is not in heat exchange relationship with the evaporator. The first and second condensers are connected in series with the compressor outlet, and one or more valves are connected to the second condenser for selectively bypassing refrigerant from the second condenser, while all refrigerant from the compressor outlet flows through the first condenser that is in heat exchange relation to the evaporator.

Abstract: A refrigeration system servicing apparatus includes a digital controller, a vessel for storing and pressurizing refrigerant, a solenoid actuated valve responsive to the digital controller for selective connection of the refrigeration system to a vacuum source, a solenoid actuated valve responsive to the digital controller for connection of the vessel to the refrigeration system, a pressure sensor for providing pressure readings to the digital controller from the low pressure side of the vacuum source, a pressure sensor for providing pressure readings to the digital controller from the vessel and means for quantifying the refrigerant in the Vessel. Three operational modes provided for are: a "vacuum" mode, during which residue material in the refrigeration system is boiled away; a "charge oil" mode, during which lubricant is added to the refrigeration system; and a "charge refrigerant" mode, during which refrigerant is added to a refrigeration system.

Abstract: A portable refrigerant recovery unit including a compressor, a condenser and an internal receiver or container for recovering refrigerant from a refrigeration unit or other container. A level measuring device determines the level of liquid refrigerant in the internal container. A control device responds to the level measuring device and disables the compressor when the liquid refrigerant in the internal container reaches a predetermined level. Refrigerant can be temporarily stored within the internal container or passed through the internal container to an external container as refrigerant is being removed from the refrigeration unit.

Abstract: A refrigerant recovery system is operated to withdraw compressible refrigerant from a refrigeration system by first withdrawing liquid refrigerant from the system being serviced through a suitable conduit and delivering the withdrawn refrigerant directly to a refrigerant storage means. In the refrigerant storage means at least a portion of the refrigerant so withdrawn exists in gaseous form and a portion of this is withdrawn from the storage means and passed serially through a compressor, a condenser, and a refrigerant expansion device before being delivered back to the refrigerant storage means where is evaporates and absorbs heat from the refrigerant within the storage means thereby cooling the storage means and lowering the pressure therein to thereby increase the withdrawal of the liquid refrigerant from the refrigeration system through the conduit. The system controlled parameters including temperature of the refrigerant and the storage means, and compressor suction and discharge pressure are sensed.

Abstract: A refrigerant recovery system comprises a compressor driven recovery machine having inlet and outlet ports, a primary refrigerant receiving and storage vessel having liquid and vapor ports, and a secondary refrigerant receiving and storage vessel having an inlet. During the refrigerant recovery process the refrigerant circuit outlet is coupled to the primary vessel liquid port, the primary vessel vapor port is coupled to the recovery machine inlet port, and the recovery machine outlet port is coupled to the vapor inlet of the secondary vessel. Operation of the recovery machine draws liquid refrigerant into the primary vessel at a high flow rate while withdrawing refrigerant vapor from the primary vessel, converting the withdrawn vapor to liquid refrigerant, and forcing the liquid refrigerant into the secondary vessel at a liquid refrigerant flow rate substantially less than the liquid refrigerant inflow rate to the primary vessel.

Abstract: Portable, hand carryable acid purification and flushing and transfer systems are provided for use in various refrigerant recovery, recycling and flushing operations performed in conjunction with an air conditioning circuit. The acid purification system is disposed within a carrying housing and includes an accumulation/distillation type acid separator piped in series with a pair of cylindrical dual core filter assemblies. A pair of refrigerant inlet and outlet fittings are externally mounted on the housing. By connecting these fittings in a forced flow refrigerant circuit the refrigerant is passed sequentially through the acid separator and the first and second filter assemblies to cleanse the refrigerant of acid and particulate impurities therein. The portable flushing and transfer system is also disposed in a carrying housing and includes a high capacity liquid refrigerant transfer pump piped in series with a check valve and a relief valve.

Abstract: A refrigerant reclaim method and apparatus is described wherein a separate primary refrigeration pathway is utilized to drive refrigerant to be reclaimed through a secondary refrigeration pathway. The primary refrigeration pathway is comprised of a compressor, the hot side of a first heat exchange element, a condenser, a receiver and an evaporator, which is in part comprised of the cold side of a second heat exchange element. The secondary refrigeration pathway is comprised of the cold side of the first heat exchange element, a oil separation chamber, the hot side of the second heat exchange element, and a refrigerant storage cylinder.

Abstract: An adsorption-type refrigerant recovery apparatus for a refrigeration and air conditioning system that has a connection unit, a refrigerant flow direction control device, a refrigerant adsorbing/desorbing device, a refrigerant/lubricant separating device, a condensation heat exchanging device, a drying/purging device, and a refrigerant reservoir. When the refrigerant enters the connection unit from the refrigeration and air conditioning system, the flow direction control device controls the refrigerant flowing through the adsorbing/desorbing device so that the refrigerant absorbs part of the heat energy of the adsorbent and is thus vaporized. The vaporized refrigerant then enters the refrigerant/lubricant separating device to separate the lubricant therein. The flow direction control device further controls the refrigerant entering the adsorbent container to allow the adsorbent to adsorb the refrigerant. When the adsorbent is saturated, the adsorbent is heated to desorb the refrigerant in a gaseous state.

Abstract: A system for recovering compressible refrigerant from a refrigeration system, of the type having a compressor for lowering the pressure in the refrigeration system to effect the withdrawal of the refrigerant therefrom, and directing the refrigerant to a storage cylinder. The system is operable in a storage cylinder cooling mode of operation wherein the temperature and pressure of the refrigerant withdrawn from the system and stored in the cylinder is lowered. A control system for limiting the pressure ratio across the compressor during operation of the recovery system is provided. The control system includes first means for determining the suction pressure of the compressor and for terminating operation of the recovery system when a desired termination pressure is reached.

Abstract: A refrigerant purification and recovery device which directly reitroduces the refrigerant to the refrigeration unit or to a storage container. The device is separable into two parts with one part containing a receiver-separator vessel and the other part containing a compressor and a condenser.

Abstract: A refrigerant reclaim system includes a compressor, a heat exchanger, an oil separator, a condenser, a chill tank, a filter-dryer and a cooling coil in the chill tank. Refrigerant to be reclaimed is drawn through the cold side of the heat exchanger, converted to a gas which is discharged into the oil separator where the gas is directed upwardly in an expanding stream. The flow of the stream is abruptly interrupted to separate oil from refrigerant. The gaseous refrigerant is passed from the oil separator through the compressor, the hot side of the heat exchanger, a condenser and into the chill tank in a liquid state. Liquid refrigerant flows from the bottom of the chill tank through a filter-dryer, an expansion device, converting it to gas, through a cooling coil, submerged in liquid refrigerant in the chill tank, into the stream exiting the oil separator and back to the compressor.

Abstract: An apparatus adapted for recovering compressible refrigeration fluid from a refrigerator means and delivering the recovered fluid under high-pressure conditions along a line to a receptacle, in fluid communication and in sequence along the line.

Abstract: Refrigerant is recovered using a single pump unit, regardless of the refrigerant's phase. This is achieved by sensing the phase of the refrigerant and changing the pump's operation accordingly. The refrigerant phase can be sensed by a temperature-responsive element, such as a thermistor, or by other phase-sensing technology. In a preferred embodiment, the pump unit is a vane pump whose rotational speed is changed in response to the refrigerant's phase. If liquid refrigerant is sensed, the pump operates at a lower speed. If gas refrigerant is sensed, the pump operates at a higher speed. The two speeds are chosen so that the pump will draw an EPA-specified vacuum on the refrigerant present. In other vane-pump embodiments, the pump's operation is changed by changing the pump's mechanical configuration, rather than its rotational speed.

Abstract: A wrapper which has a phase-change material therein is wrapped around the outer circumference of a tank used to store saturated condensed used refrigerant evacuated from a refrigeration system. The phase-change material acts as a heat exchange medium by changing between solid and liquid phases at its melting/freezing temperature selected from a particular temperature range and thus served to provide a large thermal driving force so as to cool the tank. The selected material is normally one that can be brought into its solid phase merely by contact with ice and/or remain in its solid phase for long periods without itself being refrigerated.

Abstract: An apparatus and method for controlling the charging of refrigerant into a refrigerant system is disclosed. The apparatus determines the mass amount of refrigerant charged by determining the volume of refrigerant charged, the density of the refrigerant based on its pressure as it is charged, and determines the mass amount charged from the determined density and pressure. The apparatus has a pressure compensated flow valve and determines the volume of refrigerant charged based on the amount of time refrigerant has flowed through the constant flow valve. The type of refrigerant being charged can be selected from a plurality of refrigerant types and the apparatus has a memory in which data related to density and flow characteristics of each refrigerant type is stored. The apparatus uses the data for the selected refrigerant to determine the mass amount of refrigerant charged. The apparatus further determines that the refrigerant supply tank is empty when its pressure decay exceeds a predetermined amount.

Abstract: Portable, hand carryable acid purification and flushing and transfer systems are provided for use in various refrigerant recovery, recycling and flushing operations performed in conjunction with an air conditioning circuit. The acid purification system is disposed within a carrying housing and includes an accumulation/distillation type acid separator piped in series with a pair of cylindrical dual core filter assemblies. A pair of refrigerant inlet and outlet fittings are externally mounted on the housing. By connecting these fittings in a forced flow refrigerant circuit the refrigerant is passed sequentially through the acid separator and the first and second filter assemblies to cleanse the refrigerant of acid and particulate impurities therein. The portable flushing and transfer system is also disposed in a carrying housing and includes a high capacity liquid refrigerant transfer pump piped in series with a check valve and a relief valve.

Abstract: A circuit for recovering refrigerant from a disabled refrigeration unit combines a vacuum pump, vapor pump or compressor in series with a compressor for drawing gaseous refrigerant from the disabled unit. The series arrangement of the vacuum source and the compressor provides approximately -29 inches of mercury at the suction side of the vacuum source. A condensor in series with the compressor converts the gaseous refrigerant into a liquid refrigerant and a storage tank in series with the condenser receives liquid refrigerant from the condenser. In one preferred arrangement a valve system connected in series between the condenser and the storage tank allows the storage tank to be disconnected from the circuit without release of refrigerant from the tank to the atmosphere. The circuit may also include a coil in parallel with the condenser and the compressor and helically disposed around the storage tank for cooling the storage tank.

Abstract: The invention comprises an apparatus, a method and a system for recovering and purifying a refrigerant contained in a refrigerator, an air conditioning system, a storage tank, or other source. The refrigerant is flowed sequentially through a purifying device, an expansion valve for controlling the flow of the refrigerant, one or two heat exchangers wherein heat is exchanged to convert the refrigerant into a gaseous phase, a second purifying device for separating oil from the refrigerant, a compressor-pump, a third purifying device for filtering moisture, acids, and particulates, and a moisture indicator monitors the amount of moisture present in the recovered refrigerant. The refrigerant then may be flowed into a receiving tank, and thence dispensed therefrom back into the refrigerant source, a storage tank, or recirculated again through the apparatus. The apparatus also comprises means for leak testing the refrigerant source, and for pressure-clearing obstacles from the refrigerant source.

Abstract: A device is disclosed for recovering refrigerant from a refrigeration system. The refrigerant recovery device includes a refrigerant processing flow path. The refrigerant processing flow path includes components for withdrawing the refrigerant from the refrigeration system and for processing the refrigerant so removed to remove impurities from the refrigerant. A receiver tank is provided for receiving and storing the processed refrigerant. The receiver tank includes an inlet and an outlet. Components are also provided for transferring the refrigerant from the receiver tank to a transfer tank at an initially evacuated condition, and for preventing the transfer of refrigerant between the receiver tank and the transfer tank when the transfer tank is not in an initially substantially evacuated condition.

Abstract: An adapter plate for mounting to the outlet side of a refrigeration system compressor including one or two fittings for retrieving refrigerant from the cooling system prior to servicing so as to avoid discharge of the refrigerant gas into the atmosphere. The adapter plate provides a larger fitting than typically provided in refrigerant systems, thereby enabling the retrieval process to be accomplished in a shorter amount of time.

Abstract: A refrigerant recovery system is operative in a recovery mode to recover refrigerant from an air conditioning circuit, and in a cleaning mode to cleanse the recovered refrigerant of impurities therein. In the recovery mode the refrigerant is withdrawn from the air conditioning circuit and flowed through a filter dryer by a compressor which then forces the refrigerant through a condenser into a storage container. In the cleaning mode, liquid refrigerant from within the storage container is continuously flowed through the filter dryer and then back into the storage container. To remove impurities from within the air conditioning circuit, the recovery system is also operative in a closed loop flushing mode in which liquid refrigerant from within the storage container is continuously pumped through a portion of the air conditioning circuit, filtered, and then returned to the storage container without any appreciable quantity of refrigerant being vented to atmosphere during the flushing process.

Abstract: Portable, hand carryable acid purification and flushing and transfer systems are provided for use in various refrigerant recovery, recycling and flushing operations performed in conjunction with an air conditioning circuit. The acid purification system is disposed within a carrying housing and includes an accumulation/distillation type acid separator piped in series with a pair of cylindrical dual core filter assemblies. A pair of refrigerant inlet and outlet fittings are externally mounted on the housing. By connecting these fittings in a forced flow refrigerant circuit the refrigerant is passed sequentially through the acid separator and the first and second filter assemblies to cleanse the refrigerant of acid and particulate impurities therein. The portable flushing and transfer system is also disposed in a carrying housing and includes a high capacity liquid refrigerant transfer pump piped in series with a check valve and a relief valve.

Abstract: A passive refrigerant retrieval and storage apparatus is shown for retrieving refrigerant from a cooling system prior to servicing the cooling system. The passive apparatus includes a coil collector tube within an insulated housing with an outlet from the collector tube passing through a metering valve into the housing. The collector tube is connected to the condenser outlet of a cooling system and the system compressor operated to pump pressurized liquid refrigerant into the collector tube. A small portion of the refrigerant is discharged through the metering valve into the apparatus housing where it is evaporated and causes extreme subcooling to the refrigerant in the collector tube. A return line from the housing to the inlet side of the compressor returns the evaporated refrigerant to the cooling system.

Abstract: A tubular body supports a fluid actuated tubular piston connected to operate a coupling mechanism for releasably securing the body to a valve fitting on a refrigerant receiving system. The body encloses components which define a center passage connected to the fitting for first evacuating air from the system and then for directing liquid refrigerant into the system. The passage receives an elongated valve opening member which is fluid actuated to a position opening the valve fitting, and a movable valve member closes the passage to the flow of refrigerant. The fluid actuated coupling mechanism provides for convenient and simple insertion of the tool assembly onto the fitting with no insertion force and also for automatic release of the tool assembly from the fitting after charging is completed. A fluid actuated valve member minimizes the volume of residue refrigerant which vaporizes when the tool assembly is removed from the fitting.