The four-way valve automatically reverses water flow in the condenser for about thirty seconds, once every six hours. The valve fits into the condenser supply and return piping and is custom manufactured to suit any piping configuration.
Nylon-bristled brushes are propelled through the tubes with the reversed water flow. Working in conjunction with good chemical treatment, the brushes clean the tube walls to eliminate scale formation and fouling. Each brush is designed to have a 0.025-inch interference fit in the tube wall.
Open-ended low-pressure drop catch baskets are installed in the tube ends at the tube sheet to capture the brushes in the condenser heads. Removable end-clips allow for eddy-current testing and brush replacement, which is normally recommended every four to five years.