The life and efficiency of a heating or cooling system are greatly dependent on the quality of the system water. Air and dirt problems cause frequent breakdowns and increased customer complaints. Corrosion, cavitation, and component wear are consequences of dirty, air-saturated water. Recurring problems and increased maintenance result in unnecessary costs and dissatisfied owners. Many systems now have the need for hydraulic balance due to separate circuits with variable speed pumps or the need for chiller and boiler loops. Combining all these features in a low loss header saves time and reduces installation costs. There is a solution! A hydraulically balanced system without air and dirt is possible. There is a unique four-purpose device that will remove air and dirt to keep the system clean and function as a hydraulic separator in a low loss header. It includes connections for two separate circuits, requires little maintenance, and works without strainers or filters. Less maintenance, fewer costs, satisfied owners!