What are the functions of air vent, ARV, AW & VRV

Air vent – safe guard the tank from positive and negative pressure and air lock in the utility point. ARV-Air release valve is used to release the air manually. AW – Air vent valve is used to release the air automatically VRV – Vacuum release valve is used to release the vacuum formed inside the system automatically.

All the above valves are called as safety valve.