It works i used product in bathtub where water was running out slow water is flowing freely again! Interested in becoming an alpha installer? Create your perfect paint in your perfect colour, with our colour matching service in store. Why, a plumber would be ashamed to take as long as that over a job! The hot water treatment was a real new idea for me.i never encounter any serious blocking but your idea of hot water combinations and the pepsi idea were really innovative . Simple processes.