WATER is the most precious of our natural resources, source of life and health, today we use water for multiple needs.Whatever its destination – domestic, urban, agricultural or industrial, the water we use every day is distributed by interlinking networks of pipelines which are becoming more and more complex.

In this network, the risk of pollution by ”backflow” is always present.

By siphoning or overpressure, backflow may occur when the usual direction in the distribution circuit is reversed. This return may draw water which could be polluted into the general water system thereby contaminating the drinking water.

The backflow preventer BA are in the process of different national certifications and are designed to protect drinking water systems from contamination by polluted liquids which do not present toxic or microbiological risks to human health, as defined by the health authorities.


The backflow preventer BA is composed by 3 zones: upstream, middle and downstream chamber, each chamber is fitted with pressure plug.

Two independent non return devices separate the middle zone (reduced pressure zone) from each other
zone, normally closed when no water. A discharge device (evacuation to waste) links to the middle chamber, normally closed when no water.

Automatic protection

New backflow preventers Series BA009MC are for commercial and industrial applications.

They protect the network automatically closing the two non return valves and opening the discharge device that evacuates the contaminated water by gravity.

The system is able to block anomalies and stop the water in the plant preventing the polluted water return.

Cast iron body and a complete maintenance kit

The new version, available in the range from DN65 to 250, has a cast iron casing, stainless steel rings and a cast iron discharge device with a maintenance kit with two non return valves and a discharge valve with rings.

Warranty and certifications

Watts designed the backflow preventers following the guidelines in EN 1717 – EN12729 and obtained a lot of EU approvals (ACS; UNI; WRAS; KIWA; ….).

The backflow prevents Series BA009MC, thanks to the compact sizes, make easy the maintenance. They have to be installed between two interception valves and need a filter (Series F21N).