<p>An automatic float-activated drain valve for a liquid reservoir (12) used in the accumulation of condensable materials and other contaminants from pneumatic systems. The float (66) is connected by a flexible tether (64) to a lever arm which opens a pilot valve (44) when the reservoir (12) fills with water and the float (66) moves to the top of the reservoir (12). The pilot valve (44) permits air pressure to flow to an actuator which opens the drain valve.</p>
