Combination Kinetic air release valve provides 3 functions:
- Air venting for small pockets of air release from pressurized piping system
- Air/vacuum for large air exhaust during filling of the pipeline and
- Admitting large volumes of air during draining of piping system.
Features:

Ordinary spring loaded pressure relieve valves which open at a predetermined pressure are of no use in relieving the high surge pressures encountered during in Water Hammer.
The main reasons are that they are extremely slow in opening and they close down when they encounter a negative pressure. The Water Hammer surge