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: An acoustic vapor type indicator is disclosed in which an audible signal such as a whistle is produced when a vapor is flowing through the indicator. The indicator includes an air chamber having an inlet for connection with a closed vessel containing a quantity of a gas other than air. When the closed vessel is open to the indicator, the gases within the vessel first force the air from the air chamber through an outlet orifice producing a whistle of a first pitch. Once the air has been removed and the gas within the closed vessel passes the outlet orifice, due to a change in density the pitch produced by the indicator will be changed. Alternative embodiments disclose automated pitch detection means as well as a pitch recognition device.

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.