Grundfos UPSD80-120/2 Commercial Heating Circulator have been developed to simplify installation and operation. The pump offers three speeds for adjustment of pump performance to the system in question. Grundfos UPSD Pumps are of the canned rotor type, ie-pump and motor form an integral unit without shaft seal and with only two gaskets for sealing. Otherwise known as Glandless Pumps, with there being no mechanical seal this range of pumps are practically maintenance free. Grundfos Twin Head Circulator Pumps have three separate operating modes, Alternating Operation, Standby Operation and Single-pump operation. Grundfos UPSD80-120/2 Twin Head Pumps are supplied three phase (415V) only.