
A.R.I. D-021 is a reduced bore, ultra-compact, combination air valve installed on raw, reclaimedand non-potable water transmission systems. The valve is designed to improve hydraulic operation by protecting the pipeline, increasing pipeline efficiency and reducing energy requirements. The unique body shape of the valve, enables a continuous air gap that separates the liquid from the sealing mechanism and helps to avoid deposits or blockage.
Size Unit
Size range
Pressure rating
Working pressure range
Working temperature
Maximum working temperature:
60° CMaximum intermittent temperature:
90° CAvailable construction materials
Reinforced Nylon
End connection type
Threaded male BSPT/NPT or Flanged ends to meet various requested standard
Optional add-on components
One-way Out attachment, allows for air discharge only, prevents air intake.
Vacuum Breaker, In-only attachment, allows for air intake only, prevents air discharge.
A.R.I. D-040L & D-021 Combination Air Valves in operation