Backflow preventer DISCONNECTOR BRA.ECO 3F – DN 100, L = 450 mm, flanged – SALE

Product detailed description

How the disconnector works

The BRA.ECO 3F is a flanged backflow preventer with a controllable reduced pressure zone. The body contains two spring-loaded check valves and, between them, an intermediate chamber with a safety relief valve. Under normal flow the pressure in the intermediate chamber is at least 140 mbar lower than at the inlet and the relief valve stays closed. If the inlet pressure drops (for example when the supply fails) or the pressure in the user network rises above that of the public network, the valve opens, empties the intermediate chamber to the drain and separates the two networks.

The device protects against fluids up to category 4 according to EN 1717, for example when connecting boilers, washing machines, industrial plants, laboratories or fire brigade equipment. For category 5 (microbiological and viral risk) an air gap is required. Although its nominal pressure to EN 12729 is PN 10, the manufacturer also permits its use in fire-fighting networks with operating pressure up to 12 bar.

Design

• body, upper and lower cover of GJL 250 grey cast iron, RAL 5002 epoxy coating inside and out
• EPDM seals
• test ports with mini valves for measuring the pressure upstream and in the intermediate chamber, function test with the ECO3 TEST kit
• removable cover for easy maintenance
• PN 10 flanges to EN 1092-1, length 450 mm, weight 46 kg, Kv 129 m³/h

Installation

The disconnector is installed horizontally with the relief valve facing down, in an accessible, ventilated place protected from frost and flooding. Upstream go a shut-off valve and a strainer with drain plug – without a strainer the device does not work properly – and downstream a second shut-off valve. The relief valve must be connected to the drain via the drain funnel that is part of the product, and the water must run off by gravity. Have the installation carried out by a qualified professional.

Technical data

Frequently asked questions

Why must a strainer be fitted upstream of the disconnector?
According to the manufacturer the strainer is essential for correct operation – otherwise dirt and debris from the pipework would cause malfunctions. It is fitted between the upstream shut-off valve and the disconnector and must have a drain plug.

Does the disconnector have to be connected to the drain?
Yes. During backflow the intermediate chamber empties through the safety relief valve, so it is connected to the drain via the funnel that is part of the product; the water must run off by gravity.

Is it suitable for all fluid categories?
No, it protects against fluids up to category 4 according to EN 1717. For category 5, i.e. fluids with a microbiological or viral risk, separation by an air gap is required.

Can the check valves be replaced?
Yes, once the cover is unscrewed the relief valve and both check valves are accessible. For DN 100 the instructions list the spare parts R1 K040996C80, R2 K040997C80 and RS K040998C80.