The Syphonic Outlet

Syphonic outlets are designed to reduce the entry of air into the system, if air reaches more than 40% of the volume of the pipe the syphonic action will stop. To reduce the amount of air entering the system a baffle plate is usually fitted over the orifice of the outlet, this not only reduces the amount of air being pulled into the outlet opening, it also stop a vortices forming that will draw air into the system rapidly. The best outlets have been tested and approved by the British Board of Agre´ment. Outlets should also be designed to easily accommodate the water membrane of the roof, which comes in many forms.