Flanged backflow prevention device ECO 3F Series Flanged backflow prevention device - with decompression zone, BA EN1717 type, in strict accordance with the relevant product quality standards, in line with EN12729 standards and the EN ISO 9001 standard. Product Description: ECO 3F Series Flanged backflow prevention device - with decompression zone, BA EN1717 type, in strict accordance with the quality standards of production related products, in line with EN12729 standards and EN ISO 9001 standards. Backflow prevention device consists of two spring-loaded check valve and a vacuum chamber with a vent valve (located between the two check valves middle) composition. When reflux occurs, the user may be in charge of road and pipeline effectively isolated. Reflux by siphon back (upstream pipeline rupture caused by pressure drops, the upstream water supply interruption, some pipe emptying) or back pressure (in charge of road users over pipeline pressure, such as the user additional pressure pipe with a pump) cause . When drinking water piping system connected to other users (such as washing machines, boilers, industrial systems, hospitals, laboratories, fire systems), the backflow prevention device must be installed. ECO 3F backflow prevention device while series is marked meet EN 12729 standard, PN10 pressure, but according to the design criteria and actual performance, can also be applied to the working pressure of the fire protection system in PN12. Diameter: DN65-150