Comstar's heavy duty, dirt and grease Stripper works by removing grease, wax, oil, dirt and grime from hard to REACH places in equipment such as condenser coils, air conditioners and electrical contacts. When cleaning line sets insert grime buster's nozzle into the copper line from the condenser side and spray half a can. The spray releases a stream of liquid with pressure. Thereafter, you will see grime buster's liquid and residue oil come out at the evaporator end of the line set. Any liquid left inside the line will simply evaporate. This fast acting and fast drying product leaves a pleasant lemon scent behind! contains no CFC and bio-degradable.