Air eliminators are used in liquid systems to aid in the removal of air and other gases. Many systems designed for liquid service do not operate well when air is present. One example would be flow metering. Most flow meters are designed around volumetric measurement principles. Air passing through a flow meter gets measured just as if it were a liquid, causing large flow measurement errors. An air eliminator, mounted to the top of a stilling chamber and installed upstream of the flow meter, will vent this air, and only liquid will be presented to the flow meter.