Method of liberating and removing trapped refrigerant from the interior of an air conditioning system

Abstract

A method of evacuating an automotive air conditioning system of refrigerant and recharging it with replacement refrigerant includes initially removing refrigerant from the air conditioning system, flushing the air conditioning system with hot fluid to liberate residual refrigerant from within the air conditioning system, removing the fluid and liberated refrigerant, and recharging the air conditioning system with replacement refrigerant. The hot fluid preferably is itself refrigerant in a gaseous state.

1 . A method of evacuating refrigerant from an air conditioning system and recharging the air conditioning system with replacement refrigerant, the method comprising the steps of: 
 (a) evacuating refrigerant from the air conditioning system;    (b) flushing the air conditioning system with a heated fluid to liberate residual refrigerant from within the system;    (c) evacuating the heated fluid and liberated refrigerant from the air conditioning system; and    (d) recharging the air conditioning system with replacement refrigerant.    
   
   
       2 . A method of evacuating refrigerant from an air conditioning system and recharging the air conditioning system with replacement refrigerant as claimed in  claim 1  and where in step (b) the refrigerant is heated to 200 degrees Fahrenheit or greater.  
   
   
       3 . A method of evacuating refrigerant from an air conditioning system and recharging the air conditioning system with replacement refrigerant as claimed in  claim 2  and where in step (b) the refrigerant is heated to 400 degrees Fahrenheit or greater.  
   
   
       4 . A method of evacuating refrigerant from an air conditioning system and recharging the air conditioning system with replacement refrigerant as claimed in claim  1  and where in step (b) the air conditioning system is flushed with heated fluid for at least 10 seconds.  
   
   
       5 . A method of evacuating refrigerant from an air conditioning system and recharging the air conditioning system with replacement refrigerant as claimed in  claim 4  and where in step (b) the air conditioning system is flushed with heated fluid for at least three minutes.  
   
   
       6 . A method of evacuating refrigerant from an air conditioning system and recharging the air conditioning system with replacement refrigerant as claimed in  claim 1  and where in step (b) the heated fluid is heated refrigerant.  
   
   
       7 . A method of evacuating refrigerant from an air conditioning system and recharging the air conditioning system with replacement refrigerant as claimed in  claim 6  and wherein the heated refrigerant is in a gaseous state.  
   
   
       8 . A method of evacuating refrigerant from an air conditioning system and recharging the air conditioning system with replacement refrigerant as claimed in  claim 1  and where in step (b) the heated fluid is in a gaseous state.  
   
   
       9 . A method of removing residual refrigerant from an air conditioning system after the air conditioning system has been initially purged of refrigerant, the method comprising heating a flushing fluid to a predetermined temperature, injecting the flushing fluid into the air conditioning system, leaving the flushing fluid in the air conditioning system for a predetermined time to heat and liberate residual refrigerant therein, and removing the flushing fluid and liberated refrigerant from the air conditioning system.  
   
   
       10 . The method of  claim 9  and wherein the heating step comprises heating the flushing fluid to at least 200 degrees Fahrenheit.  
   
   
       11 . The method of  claim 9  and wherein the heating step comprises heating the flushing fluid to at least 400 degrees Fahrenheit.  
   
   
       12 . The method of  claim 9  and wherein the leaving step comprises leaving the flushing fluid in the air conditioning system for at least 10 seconds.  
   
   
       13 . The method of  claim 9  and wherein the flushing fluid is refrigerant.  
   
   
       14 . The method of  claim 9  and wherein the air conditioning system is an automotive air conditioning system.  
   
   
       15 . A method of removing residual refrigerant from an air conditioning system comprising heating a flushing fluid to a predetermined temperature, flushing the air conditioning system with the flushing fluid for a predetermined time to liberate residual refrigerant; and evacuating the flushing fluid and liberated refrigerant from the air conditioning system.