Tianjin U-ideal High performance vacuum breaker air release Valve;Slow closing  plug Valve eliminates air and prevents vacuum formations in pipelines. A large venting orifice and large float clearances freely exhaust or admits air during pipeline filling or draining
These valves are designed to protect pipelines from air lock and vacuum collapse.
Advantages include:
Automatically Eliminates Air Pockets
Easily Serviced Without Removal from Pipeline
Simple, Effective Patented Design
Corrosion Resistant Materials of Construction
Engineered For Lasting Service
Applications for Tianjin U-ideal float-type air vents include hydronic heating systems, water service lines, water storage tanks, centrifugal pumps, gas lines, solvent filters and similar equipment. Operation is completely automatic, and the simple design and quality mechanism make operation trouble-free and maintenance infrequent.

Why remove air from a water system?
Every building services engineer knows that air trapped in either a hot or chilled water system can cause trouble, such as excessive noise, corrosion and increased maintenance costs. Air can cause air locks which
inhibit the filling of the system or the priming of pumps. It can seriously affect the accuracy of flow measurement meters and regulating valves. Under extreme conditions it may even temporarily decommission plant.
Air and other incondensable gases considerably reduce heat transfer efficiency. A film of air 1 mm thick presents the same barrier to heat transfer as a wall of copper 13 m thick!
Entrapped air in any water system is a threat to thermal efficiency. It is particularly damaging in a chilled water system which does not have the natural deaerating ability of hot water.