Air valve

On top of HVAC piping, solar thermal systems, storage tanks, and industrial equipment, you can often spot a small brass or stainless steel valve. It requires no manual operation, yet quietly and automatically expels air from the system. This is a compact automatic air vent valve (also called an automatic air release valve). This article focuses on float-type automatic air vent valves ranging from DN15 to DN32, with bodies made of brass or stainless steel, providing a systematic explanation of their working principle, construction materials, installation methods, and application scenarios.

Air in water pipelines is a hidden threat to system efficiency and pipe longevity. Whether it takes the form of air pockets accumulating at high points in long-distance water mains or cavitation caused by negative pressure during pump start-up and shutdown, entrapped air that is not promptly expelled can reduce conveyance capacity, induce water hammer, and even cause pipeline rupture.