Series WAV Air Valves

First, as the line is being filled with water they allow large quantities of air to be vented from the pipeline. When air has been completely vented, water enters the valve causing the stainless-steel float to rise and seal tightly against the seat to prevent leakage. Second, when the line is drained, either intentionally or as a result of power failure or pipeline breakage, the air vacuum valve responds to a negative pressure and opens, allowing air to re-enter the valve and line preventing a vacuum from forming which could lead to damaging the pipeline.