Product description
The main purpose of backflow preventers is to prevent the contaminated water back-flow, keeping it from entering the water-supply network.
Backflow may occur due to a reduction in pressure in the main water-supply network (day-night oscillations, damaged equipment ...).
Backflow preventers are installed at points, where major distribution networks connect to user networks, i.e. at the point beyond which there exist a risk of water contamination.
Common check-valves do not offer 100% protection against backflow.
In potable water distribution networks, a contamination may occur due to:
- Damage to network components,
- Ingress of polluted water from individual points of withdrawal (POWs), connected to a distribution network.
The use of backflow preventers is envisaged for the following buildings:
- Blocks of flats,
- Industrial buildings,
- Heat-only boiler stations (teleheating),
- Combined heat and power plants (CHP),
- Hospitals,
- Fire-fighting installations,
- Irrigation systems,
- Public spas / pools,
- Hotels
- Fairs,
- Sportive/competitive and all other public entertainment events ...
Types of backflow preventers
| CALEFFI | backflow preventers for fixed installations; 574-575 series |
| BEULCO | backflow preventers for hydrant posts |
The backflow preventer conforms to the EN 1717 - Protection against pollution of potable water in water installations and general requirements of devices to prevent pollution by backflow.
Advantages of backflow preventers:
- Dimensions (1/2'' — 1 1/4'') are made of cast brass which prevents the leaching of zinc (Zn) into water;
- Dimensions (1 1/2'' and 2'') are made of bronze;
- All internal components are made of health-safe materials;
- Backflow preventers have suitable forms and sizes (do not require a lot of mounting space);
- The internal form of backflow preventers prevents accumulation of deposits;
- Easy to mount and inspect;
- Service and maintenance are possible on-site (disassembly is not required);
- The outlet segment of the backflow preventer is made such that it prevents the mounting of any outlet elements which would negatively affect the operation of the backflow preventer (siphon effect).
