Cla-Val 210-03 and 610-03 Altitude Valves control the high water level in reservoirs without the need for floats or other devices. They are non-throttling valves that remain fully open until the shut-off point is reached. These valves close at a high water level. Water is withdrawn from the reservoir through a separate discharge line or through a check valve located in a by-pass line around the altitude valves. The valves delay opening until the water in the reservoir lowers to the desired level. The low level is adjustable from 1 to 15 feet from the high water shut-off point.

Used on reservoirs where water is withdrawn from the reservoir through a separate line. When the water level lowers to the desired opening point, the pilot control opens the main valve to refill the reservoir. The difference between the high-level shut-off and the low-level opening is adjustable between a minimum of one foot and a maximum of fifteen feet.