Refrigerant recovery device and method of operation

Abstract

A refrigerant recovery device comprising a pump; a heat rejecting heat exchanger disposed in fluid communication with the pump; a refrigerant storage container disposed in fluid communication with the heat rejecting heat exchanger and the pump; a fluid interface disposed in fluid communication with the pump and configured for fluidly connecting the refrigerant recovery device to a refrigerant containing device; and a plurality of valves disposed in fluid communication with at least one of the pump, the heat rejecting heat exchanger, the refrigerant storage container, or the fluid interface and configurable to establish a first fluid pathway fluidly connecting the refrigerant containing device to the refrigerant storage container, and a second fluid pathway fluidly connecting the heat rejecting heat exchanger to the refrigerant storage container.

What is claimed is: 
     
         1 . A refrigerant recovery device comprising:
 a pump;   a heat rejecting heat exchanger disposed in fluid communication with the pump;   a refrigerant storage container disposed in fluid communication with the heat rejecting heat exchanger and the pump;   a fluid interface disposed in fluid communication with the pump and configured for fluidly connecting the refrigerant recovery device to a refrigerant containing device; and   a plurality of valves disposed in fluid communication with at least one of the pump, the heat rejecting heat exchanger, the refrigerant storage container, or the fluid interface and configurable to establish a first fluid pathway fluidly connecting the refrigerant containing device to the refrigerant storage container, and a second fluid pathway fluidly connecting the heat rejecting heat exchanger to the refrigerant storage container.   
     
     
         2 . The refrigerant recovery device of  claim 1 , wherein the first fluid pathway extends from the refrigerant containing device, through the fluid interface, the pump and the heat rejecting heat exchanger, and into the refrigerant storage container, and the second fluid pathway extends from the heat rejecting heat exchanger through the pump and into the refrigerant storage container. 
     
     
         3 . The refrigerant recovery device of  claim 1 , wherein the second fluid pathway is dead ended upstream of the heat rejecting heat exchanger. 
     
     
         4 . The refrigerant recovery device of  claim 1 , wherein the first fluid pathway is configured such that during operation the pump pressurizes the heat rejecting heat exchanger as it pushes a refrigerant flow therethrough and the second fluid pathway is configured such that the pump depressurizes the heat rejecting heat exchanger as it draws the refrigerant flow into the refrigerant storage container. 
     
     
         5 . The refrigerant recovery device of  claim 1 , further comprising a second pump, and wherein the second pump is disposed in the second fluid pathway disposed in fluid communication with, and interposed between, the heat rejecting heat exchanger and the refrigerant storage container. 
     
     
         6 . The refrigerant recovery device of  claim 1 , further comprising an oil separator disposed in the first fluid pathway in fluid communication with, and interposed between, the pump and the heat rejecting heat exchanger. 
     
     
         7 . The refrigerant recovery device of  claim 1 , further comprising an oil separator disposed in the first fluid pathway. 
     
     
         8 . The refrigerant recovery device of  claim 1 , further comprising a pressure relief device disposed in fluid communication with the heat rejecting heat exchanger. 
     
     
         9 . The refrigerant recovery device of  claim 1 , wherein the refrigerant containing device contains a refrigerant to be recovered comprising a refrigerant having a 100-year global warming potential relative to a carbon dioxide reference gas of less than or equal to 2000. 
     
     
         10 . The refrigerant recovery device of  claim 1 , wherein the heat rejecting heat exchanger comprises a heat conducting coil disposed in thermal communication with a consumable heat sink. 
     
     
         11 . The refrigerant recovery device of  claim 1 , further comprising a controller in operable communication with the pump and the plurality of valves and configured to change an operating state of one or more valves of the plurality of valves to establish one of the first fluid pathway and the second fluid pathway based on one or more feedback conditions. 
     
     
         12 . The refrigerant recovery device of  claim 11 , wherein the one or more feedback conditions comprise at least one of a pressure of the refrigerant containing device, a pressure of the heat rejecting heat exchanger, a pressure of the refrigerant storage container, a pressure of the oil separator, a temperature of the refrigerant containing device, a temperature of the heat rejecting heat exchanger, a temperature of the refrigerant storage container, a temperature of the oil separator, or an elapsed time. 
     
     
         13 . The refrigerant recovery device of  claim 1 , wherein the establishment of the first fluid pathway is mutually exclusive with the establishment of the second fluid pathway. 
     
     
         14 . The refrigerant recovery device of  claim 1 , further comprising a movable structure configured to hold one or more of the fluid interface, the pump, the heat rejecting heat exchanger, the refrigerant storage container, or the plurality of valves. 
     
     
         15 . A method of removing a refrigerant from a refrigerant containing device comprising:
 pumping the refrigerant along a first fluid pathway from the refrigerant containing device through a heat rejecting heat exchanger and into a refrigerant storage container until an initial pull-down threshold condition is satisfied;   cooling the refrigerant as it passes through the heat rejecting heat exchanger; and   pumping the refrigerant along a second fluid pathway from the heat rejecting heat exchanger to the refrigerant storage container until a final pull-down threshold condition is satisfied.   
     
     
         16 . The method of  claim 15 , wherein the initial pull-down threshold condition comprises reaching one or more of a predetermined pressure condition within the refrigerant containing device, a predetermined temperature condition within the refrigerant containing device, a predetermined pressure condition within the heat rejecting heat exchanger, a predetermined temperature condition within the heat rejecting heat exchanger, a predetermined pressure condition within the refrigerant storage container, a predetermined temperature condition within the refrigerant storage container, or a predetermined initial pull-down time duration. 
     
     
         17 . The method of  claim 15 , wherein the final pull-down threshold condition comprises reaching one or more of a predetermined pressure condition within the heat rejecting heat exchanger, a predetermined temperature condition within the heat rejecting heat exchanger, a predetermined pressure condition within the refrigerant storage container, a predetermined temperature condition within the refrigerant storage container, or a predetermined second pull-down time duration. 
     
     
         18 . The method of  claim 15 , further comprising at least partially obstructing the second fluid pathway while refrigerant is pumped along the first fluid pathway; and at least partially obstructing the first fluid pathway while refrigerant is pumped along the second fluid pathway. 
     
     
         19 . The method of  claim 15 , further comprising pressurizing the heat rejecting heat exchanger when the refrigerant is pumped along the first fluid pathway and depressurizing the heat rejecting heat exchanger when the refrigerant is pumped along the second fluid pathway. 
     
     
         20 . The method of  claim 15 , further comprising:
 providing a refrigerant removal device comprising a pump, the heat rejecting heat exchanger and the refrigerant storage container disposed in configurable fluid communication, wherein the refrigerant removal device is configurable between at least a first configuration establishing the first fluid pathway and a second configuration establishing the second fluid pathway;   configuring the refrigerant removal device in the first configuration;   fluidly connecting the refrigerant containing device to the refrigerant removal device;   pumping the refrigerant with the pump along the first fluid pathway while at least partially obstructing the second fluid pathway,   cooling the refrigerant in the heat rejecting heat exchanger before it enters the refrigerant storage container;   receiving the refrigerant in the refrigerant storage container; and   pumping the refrigerant with the pump along the second fluid pathway while at least partially obstructing the first fluid pathway.