Patent attributes
An apparatus for automatically controlling the water level of a pool includes a first tank having a first water level, the first tank including a first float valve connected to a high pressure water source. A second tank has a second water level that is below the first water level, thereby defining a pressure head between the two tanks. The second tank includes a second float valve that is supplied by the pressure head between the two tanks, so that the second float valve receives low pressure water and is adapted to open and close within a range that spans a fraction of an inch. The second tank also includes an adjustable drain opening. The second tank water level varies between an upper limit set by the drain opening and a lower limit set by the opened position of the second float valve. The second tank is connected directly to the pool in open flow communication, so that the water level set in the second tank in turn sets the water level of the pool.
