Dry Riser – Air Release Valve
Dry Riser systems are commonly installed in High Rise buildings for the protection of the building from risk of fire, providing an on-site water supply that can be easily accessed by attending fire crews. As the name implies a Dry Riser system is free from water until connected at ground level to a pressurised water supply via the dry riser inlet breeching.
Whilst dormant the vertical pipework interconnecting the dry riser system to each floor of the building is filled with air. When a pressurised water supply is connected to the inlet breeching the air is forced up the pipework ahead of the water to the pipe end (roof or top floor level).
This air has to be released to allow water to reach all landing valves on every floor of the building. Without complete removal of all air within the dry riser pipework fire fighting performance would be severely impaired and water flow may be denied completely on upper levels. Delta Fire’s dry riser air release valve provides the ideal solution to this and any pressurised air is forced out through the air release valve allowing for successful transference of water to all points.
When draining the dry riser system after use the air release valve works in complete reverse allowing an ingress of air facilitating the water’s escape. Without the air release valve a vacuum would be created preventing full expulsion of the water.
The Delta Fire Air Release Valves are manufactured from copper alloy to BS2874 and avilable in two inlets – 3/4″ or 1″ BSP Male, however the 1″ BSP male inlet is most commonly used. All valves are tested to 20 bar.
A full range of Dry Riser equipment is available from Delta Fire including inlet breechings, gate valves, pressure regulating valves and inlet & outlet cabinets.