Sealed System and a Method For Defrosting an Evaporator

Abstract

The present subject matter provides a sealed system for an appliance. The sealed system includes a compressor operable to generate a flow of compressed refrigerant, an evaporator and a drain trough disposed below the evaporator. A bypass conduit fluidly couples a bypass valve and the evaporator. The bypass valve is configured for selectively directing refrigerant from a condenser around an expansion device to the evaporator. A portion of the bypass conduit is positioned at and connected to the drain trough. A related method for defrosting an evaporator is also provided.

What is claimed is: 
     
         1 . A sealed system for an appliance, comprising:
 a compressor operable to generate a flow of compressed refrigerant;   a condenser disposed downstream of the compressor such that the condenser receives the flow of compressed refrigerant from the compressor during operation of the compressor;   a fan positioned proximate the condenser and operable to generate a flow of air across the condenser;   an expansion device;   an evaporator;   a drain trough disposed below the evaporator;   a bypass valve disposed downstream of the condenser; and   a bypass conduit fluidly coupling the bypass valve and the evaporator, the bypass valve configured for selectively directing refrigerant from the condenser around the expansion device to the evaporator via the bypass conduit, a portion of the bypass conduit positioned at and connected to the drain trough.   
     
     
         2 . The sealed system of  claim 1 , wherein the drain trough defines a length, the bypass conduit contacting the drain trough along the length of the drain trough. 
     
     
         3 . The sealed system of  claim 1 , wherein the bypass conduit defines a constant internal diameter. 
     
     
         4 . The sealed system of  claim 1 , wherein the fan is configured to deactivate whenever the bypass valve directs refrigerant from the condenser around the expansion device to the evaporator. 
     
     
         5 . The sealed system of  claim 1 , wherein the sealed system is charged with a flammable refrigerant. 
     
     
         6 . The sealed system of  claim 5 , wherein the flammable refrigerant comprises a flammable alkane, hydrocarbon or organic compound. 
     
     
         7 . The sealed system of  claim 1 , further comprising an electric heating element mounted to the bypass conduit. 
     
     
         8 . The sealed system of  claim 7 , wherein the electric heating element is encased within foam insulation. 
     
     
         9 . The sealed system of  claim 1 , wherein the sealed system does not include an electric heating element disposed at an outer surface of the evaporator. 
     
     
         10 . A method for defrosting an evaporator within an appliance, comprising:
 running a compressor of the appliance during a condenser preheat, a condenser fan of the appliance being deactivated during the condenser preheat such that a temperature of a condenser of the appliance increases while the compressor is running during the condenser preheat;   actuating a bypass valve of the appliance such that refrigerant from the condenser bypasses an expansion device of the appliance and flows to the evaporator; and   running the compressor during an evaporator defrost, the temperature of the condenser decreasing while the compressor is running during the evaporator defrost.   
     
     
         11 . The method of  claim 10 , wherein the condenser fan is deactivated during the evaporator defrost. 
     
     
         12 . The method of  claim 10 , wherein a bypass conduit fluidly coupling the bypass valve and the evaporator is connected to a drain trough disposed below the evaporator. 
     
     
         13 . The method of  claim 12 , wherein a portion of the bypass conduit extends along a length of the drain trough. 
     
     
         14 . The method of  claim 12 , further comprising operating an electric heating element mounted to the bypass conduit during the evaporator defrost. 
     
     
         15 . The method of  claim 14 , wherein the electric heating element is encased within foam insulation. 
     
     
         16 . The method of  claim 10 , wherein the refrigerant is a flammable refrigerant. 
     
     
         17 . The method of  claim 16 , wherein the flammable refrigerant comprises a flammable alkane, hydrocarbon or organic compound.