When water enters the composite exhaust valve, the floating ball stops at the bottom of the ball barrel for a large amount of exhaust. When the gas is exhausted, the water enters the composite exhaust valve and floats the ball through the ball barrel until it is closed, stopping the exhaust. When the pipeline is running normally, a small amount of gas will naturally be produced. At this time, the gas will concentrate to a considerable extent in the upper part of the pipe, and the water inside the composite exhaust valve will drop. The floating ball will lower along the water and the gas will be discharged from the small hole.

If there is a power outage and pump shutdown, and the water flow in the pipeline is empty, negative pressure will occur at any time. The float will descend along the water, and the small hole will be opened to drive the large hole for a large amount of air replenishment to ensure the safety of the pipeline. Note: The pressure of the composite exhaust valve during use should not be lower than 0.03Mpa. If it is lower than 0.03Mpa, the exhaust valve is prone to water leakage. A valve must be provided for maintenance purposes.