An air lock is gas trapped in a high point of a liquid-filled pipe system. The gas, being lighter than the liquid, rises to the highest point and restricts the flow of liquid. In very tall systems, the gas can prevent flow entirely.
Flushing the system with high flow or pressures can help move the gas away from the highest point, or a tap can be installed to permit the gas to be vented.
Famous quotes containing the words air and/or lock:
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—Henry David Thoreau (1817–1862)
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Wi ae lock of his yellow hair
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—Unknown. The Lament of the Border Widow (l. 25–28)