Patent ID: 7690054

Claim:
A water level control apparatus located adjacent to a pool, said water level control apparatus comprising: a first tank having a first water level; a second tank having a second water level below said first water level, and a pressure head in said first tank equal to the difference between said first and second water levels, wherein said second tank connected directly to the pool for free water flow therebetween so that the second water level in said second tank determines the water level in the pool; a first float valve in said first tank for setting said first water level; a second float valve in said second tank for setting a lower limit for the range of said second water level; means for supplying said second float valve with the pressure head from said first tank, whereby low pressure water is fed to said second float valve from said first tank, said second float valve opening and closing within a narrow vertical range to precisely control said lower limit for the range of said second water level; an overflow drain fitting supported in said second tank, said overflow drain fitting having an opening that sets an upper limit for the range of said second water level, and means for connecting said overflow drain fitting to an external drain outside of said second tank, said overflow drain fitting is connected to a first vertical support rod via a first support arm disposed in said second tank, and said overflow drain fitting is adjusted vertically via a first vertically adjustable support member slidably mounted on said first vertical support rod; and means for vertical adjustment of the position of said second float valve to selectively vary said lower limit of said range of said second water level, wherein said means for vertical adjustment includes a second support arm and a second vertically adjustable support member disposed in said second tank, said support arm supported said second float valve, and said second float valve is adjusted vertically via said second vertically adjustable support member that slidably mounted on a second vertical support rod.