Backflow preventer with reduced pressure zone DISCOBLOC BA - Series H2 10 Designed to protect drinking water networks from backflow of polluted water due to: - a pressure drop in the network - a back pressure from a potentially non potable water network. Description • Standard local authority sanitary regulations (art. 16.1) make it obligatory for owners of installations, which are potentially dangerous, to protect public drinking water network and the internal network from the risk of the backflow of polluted water, this being by means of an approved and regularly maintained device. • Reliability: - Controllable check valve with upstream, downstream and intermediate pressure gauge taps, - Security air gap with discharge valve, in case of upstream pressure drop, - Head loss lower than standard’s requirements. • Anticorrosion protection: - Sub set of valve and seat in bronze, stem and spring made of stainless steel, - Body in ductile iron with epoxy powder coating. • Maintenance in situ without dismantling. - EN 12729 - NF E 29-305-1 and ISO 51752 for face-to-face dimensions. - Global EN 1717. • NF ANTIPOLLUTION mark. Technical data • Range: DN 150 to 250. • Maximal working pressure: PN 10. • Temperatures: +10°C to +60°C (maximum temperatures for backflow +90°C). • Flanges: ISO PN10, ISO PN16 on request. Applications • Drinkable water networks.

Body DN150 DN200 and 250 Bonnet Bolts (bonnet) Discharge sub set Supporting disc + spring Discharge stem Upper disc Diaphragm Valve holder Lower disc Discharge check valve Seat Diaphragm support Upstream check valve sub set Body Axix Check valve Seat O-rings Downstream check valve sub set Split ring Pressure cocks Discharge funnel sub set Saddle Funnel Bolts Chamber connecting set DN 150 Connection O-rings Upstream pressure sub set DN 200 to 250 Connection Cast iron/EN-GJL 250 Ductile iron/EN-GJS 450-10 Bronze/CuSn5Zn5Pb5 Steel A2 Bronze/CuSn12 PTFE coated stainless steel /X8CrNiS 18-9 + PETP...

Operation principle Description The Discobloc consists of a body closed by a bonnet, an upstream spring loaded check valve (1) and a downstream spring loaded check valve (2). The whole delimits 3 different pressure zones : upstream zone A, intermediate zone B and downstream zone C. The intermediate zone contains a discharge device (3) in the lower part and is connected by a spindle to the main diaphragm (4) and to the compensating diaphragm (5). This mobile unit is drawn upwards by an external spring (outside water) (6) with a calculated force, calibrated in factory. Diaphragms (4) and (5) enclose...

Location of backflow preventer • On a drinking water network for protecting water supply points for sanitary use: wash-basins, showers, kitchens, etc. the Discobloc is to be located at the limit of pollution generating zones such as : collective central heating, internal fire-fighting networks with stagnant water under pressure, garden watering systems, specialized workshops handling dangerous products, laboratories, etc • At the point at which the drinking water is supplied, after the water meter, for protecting the public network, in case of installations which are complex, dangerous and difficult...