The Shurflo 5059-1311-D011 Automatic Demand 12V DC Diaphragm Pump features a built-in pressure switch that reacts to outlet pressure and interrupts power at a preset shutoff pressure indicated on the pump label. As soon as outlet pressure drops below a predetermined limit, usually 15-20 PSI less than the shutoff pressure, the switch closes and the pump will only operate until the shutoff pressure is achieved. This built-in pressure switch protects the pump in the event of dead-heading.
