Methods and devices to prevent fluid migration in a refrigeration system during an off cycle

Abstract

Embodiments to prevent Off Cycle fluid migration in a refrigeration system are described. The embodiments described herein allow a fluid, such as oil from a crankcase sump of a compressor of the refrigeration system, to flow into an anti-fluid migration apparatus positioned in-line along a suction line of the refrigeration system. The fluid can be accumulated in the anti-fluid migration apparatus. The accumulated fluid may form a fluid flow barrier to prevent Off cycle refrigerant migration in the suction line.

What claimed is: 
     
         1 . A refrigeration system comprising:
 a container of the refrigeration system configured to contain a fluid with a fluid level plane when the refrigeration system is in an Off cycle of the refrigeration system;   a refrigerant line;   a trap positioned in-line along the refrigerant line, the trap including a flow passage, at least a section of which is positioned lower than the fluid level plane in the container; and   a conduit in fluid communication with the flow passage and the container;   wherein the conduit is configured to allow fluid communication between the container and the flow passage of the trap when the refrigeration system is in an off cycle.   
     
     
         2 . The refrigeration system of  claim 1 , further comprising:
 a flow control device positioned along the conduit.   
     
     
         3 . The refrigeration system of  claim 1 ,
 wherein the flow control device has an “open” state that allows fluid communication between the container and the flow passage of the trap through the conduit, and an “off” state that prevents fluid communication between the container and flow passage of the trap through the flow control device.   
     
     
         4 . The refrigeration system of  claim 3 , wherein the flow control device is in the “open” state when the refrigeration is in an Off cycle, and in the “closed” state when the refrigeration system is in an On cycle. 
     
     
         5 . The refrigeration system of  claim 2 , further comprising:
 a Schrader valve positioned between the container and the conduit, wherein the conduit is connected to the Schrader valve.   
     
     
         6 . The refrigeration system of  claim 2 , wherein the flow control device is a solenoid check valve. 
     
     
         7 . The refrigeration system of  claim 2 , wherein the flow control device is an orifice in the conduit. 
     
     
         8 . The refrigeration system of  claim 1 , wherein the trap is a U shaped section of the refrigerant line. 
     
     
         9 . The refrigeration system of  claim 2 , wherein the container is a crankcase of a compressor of the refrigeration system. 
     
     
         10 . The refrigeration system of  claim 1 , wherein the container is an oil separator. 
     
     
         11 . The refrigeration system of  claim 1 , wherein the refrigerant line is a suction line of the refrigeration system. 
     
     
         12 . An anti-fluid migration apparatus to prevent Off cycle fluid migration in a refrigeration system comprising:
 a refrigerant line;   a trap having a flow passage, the flow passage configured to be positioned in-line of the refrigerant line; and   a conduit in fluid communication with the flow passage of the trap and a crankcase of a compressor of the refrigeration system;   wherein the flow passage of the trap is configured to receive a fluid through the conduit, and allow the received fluid to accumulate in the trap so as to form a fluid barrier to prevent fluid migration through the flow passage of the trap.   
     
     
         13 . The anti-fluid migration apparatus of  claim 12 , wherein the flow control device has an “open” state that generally allows fluid communication between the crankcase sump and the flow passage of the trap through the conduit, and an “off” state that generally prevents fluid communication between the crankcase sump and the trap through the conduit. 
     
     
         14 . The anti-fluid migration apparatus of  claim 12 , wherein the flow control device is in the “open” state when the refrigeration is in an Off cycle, and in the “closed” state when the refrigeration system is in an On cycle. 
     
     
         15 . The anti-fluid migration apparatus of  claim 12 , wherein the flow control device is an orifice in the conduit. 
     
     
         16 . The anti-fluid migration apparatus of  claim 12 , wherein the refrigerant line is a suction line of the refrigeration system. 
     
     
         17 . A method of preventing Off cycle fluid migration in a refrigeration system comprising:
 during an Off cycle of the refrigeration system, directing a first fluid from a container of the refrigeration system to accumulate in a section of a refrigerant line of the refrigeration system; and   forming a fluid barrier in the section of the suction line with the first fluid accumulated in the section of the suction line to prevent a second fluid from flowing in the suction line.   
     
     
         18 . The method of  claim 17  further comprising:
 during an On cycle of the refrigeration system, directing the first fluid accumulated in the section of the suction line to flow from the section of the suction line to the container through the suction line. 
 
     
     
         19 . The method of  claim 17 , wherein the first fluid is a lubricant and the second fluid is a refrigerant. 
     
     
         20 . The method of  claim 17 , wherein the refrigerant line is a suction line of the refrigeration system.