Refrigerant Recovery machines have been in use before EPA certifications and environmental concerns arose.  Although they were not widely used at first rising prices and government regulations mandated that all appliances containing refrigerant "FREON" need to be recovered before servicing the sealed system or disposing of the appliance.  

​

Recovery or Recovering is basically using a pump that pulls the refrigerant from the appliance, then compresses it into a recovery cylinder.​