The Pedrollo twin pump sets are also called Combipress pressure boosting sets. They are pre-assembled and pre-wired for ease of installation. When operating, the second pump will cut in automatically when there is a drop in pressure. They also start alternately through a relay in the panel. They range from 11/2” to 6” and cater for flows up to 4,000 litres/min and working pressures to 10 bar.