Float Valves
Float Valve uses a sub - valve (floating ball switch) to control the main valve. When the water level elevates to the full water level set by sub-valve (floating ball switch) , the sub - valve (floating ball switch) closes and the back pressure chamber inside the main valve accumulates pressure rapidly, which reversely pushes the piston valve to close. By this mechanism, the float valve can thus control the water level. In order to save space inside the pool and for easy maintenance, it is recommended to install the float valve outside the pool. http://www.watervalve.co.in/float-valve.html