The rugged 0015 3-Speed circulator is specifically designed to provide dial-in precision to meet the requirements of any hydronic heating system, including radiant and higher head systems. In radiant applications, its’ 3-Speed switching capability gives you the fine tuning control to match a wide combination of tube diameters and lengths of run. The 0015 delivers the highest starting torque in its class and is a direct replacement for the Grundfos UPS15-58. The Stainless steel 0015 is ideal for potable water and hot water recirculation systems and directly replaces a Grundfos UPS15-55 .