Circulation pump for unvented and pressurized or open vented domestic hot water systems. Also suitable for solar energy systems. Bronze pump body. Die-cast aluminium motor casing. Technopolymer impeller. Ceramic motor shaft mounted on graphite bushings lubricated by the same pumped liquid. Stainless steel rotor
liner, stator liner and closing flange. Ceramic thrust bearing ring, ethylene-propylene seal rings. The two- or four-pole, asynchronous, wet-rotor motor is protected for resistance and requires no overload protection.