Circulators Circulate heated or chilled water in residential or light commercial hydronic systems; also used in zoning large installations. Standing circulator on many O.E.M. boilers. Resilient mounted split phase motor with overload protection & sleeve bearings. One piece dynamically balances impeller. Stainless steel shaft and bronze sleeve bearings. Carbon/Ceramic seal assembly. Durable one piece spring coupling. Designed to efficiently circulate heated or chilled water in residential or light commercial hydronic systems. Proven performance Dependable, quiet operation Resilient mounted, split phase motor with built-in overload protection Proven pump construction Factory tested Easy, low-cost service