Model F-127 An altitude control valve controls the level of high rise overhead tank(ESR).When the level in the tank drops below the set value, this pressure drop is sensed by Altitude Pilot, which opens the valve. When the tank is filled up/ reaches the set level, this high pressure is sensed by Altitude-Pilot, which closes the main valve and prevents overflow. This type of Altitude Control Valve should be used when the supply pressure is appreciably higher than the head developed by a full ground storage tank or reservoir. Higher water saving by low cost automation. Height differential of level is adjustable with simple adjusting screw. Valve and senseline are installed at the ground level,Eliminating risky maintenace at the top of tank.