Cycle Gard® Constant Pressure Pump Control Valves automatically regulate downstream pressure and provides a constant pressure regardless of the system water flow demand until the demand on the system is no longer required. Depending on the valve model, an internal or external by-pass allows the system pressure to slowly rise under low demand and fill the tank. When the pressure switch setting is reached, the pump shuts off. Cycle Gard® valves prevent the pump from short cycling which allows for a smaller pressure tank.