The Filtration Group PiW 2175 coalescer was specifically designed to separate water from hydraulic fluids, diesel and marine diesel oil. Water causes turbidity, often visible to the naked eye. This is why mechanical separation is recommended, using the technique based on the coalescence principle. The droplets of water in the pressurised fluid are collected in several layers and joined in larger units. At this point, the drops come into contact with a special water-repellent fabric, where separation occurs.