ACO Building Drainage has introduced a range of backflow valves that provide protection for both private and commercial properties that are vulnerable to flooding, and are suitable for grey and black water applications. The ACO Quatrix valves are designed to be installed in the discharge pipes from premises to prevent flooding that might be caused by excessive storm water or pumping station failures resulting in a high backflow from the main sewer system. ACO Quatrix units incorporate a pressure sensor located in the valve body. Working in conjunction with a high torque DC motor, this is used to control a motorised flap, which automatically closes against a watertight seal whenever a backflow from the sewer exists. The motor then automatically reopens the watertight flap once the backflow from the sewer abates. These high performance devices ensure reliable operation in polluted black water conditions. They also feature a secondary flap with manual override that can be closed during construction or refurbishment programmes to prevent odours entering the building or to act as a failsafe should the first flap fail. In the event of mains power failure, a battery back up facility ensures reliable operation for 24 hours until mains power is restored.