Fluid Control Equipment
Rapid Initial Air Vents
VA Series
Swiftly discharge all air/gas in pipes upon startup
Rapid initial air vents feature a large orifice, allowing them to discharge large quantities of air in a short time. This makes them the ideal choice for removing air from water tanks and water supply pipes during startup.
Once the initial air has been discharged, the valve will close and typically will not open again during normal operation. However, when pressure in the pipes falls to near or below atmospheric pressure, the valve will open once more. This allows air to enter, preventing vacuum conditions from forming within the pipes and allowing liquid to be easily passed downstream.
Though rapid initial air vents are able to discharge large quantities of air quickly, once the valve closes, it will not open again as long as a pressure differential is maintained. If it is necessary to continuously discharge air during normal operation, please use this product together with an automatic air vent.
Air Vents Pamphlet (1930 KB)
Benefits and Features
Automated Initial Air Discharge
The large-size valve seat rapidly discharges initial air. The float responds with great sensitivity to condensate levels, automatically closing the valve and thereby eliminating the need for manual labor.
Long Service Life
- Simple construction with no levers or hinges
- Only one moving part: the Free Float®. This eliminates concentrated wear and provides long service life.
Tight Sealing
Provides a tight, reliable seal
Rapid Initial Air Vents (all series)
- Can function as a vacuum breaker by allowing air to flow in when a vacuum forms
VAS & VA Series
- Precision-ground float, rubber valve seat
VS1A Series
- High precision-ground float, 3-point seating
- Can be used with liquids with specific gravities as low as 0.8
Application Areas
Rapid initial air vents are suitable for:
- instances where there is a need for the rapid discharge of air upon system startup
- processes which require expedited water supply
- water supply pipes, water tanks, water pumps (VAS, VA)
- storage tanks for non-water liquids (VS1A, non-flammable and non-corrosive liquids)
*Once the valve closes after discharging initial air, it will not open again, even if air enters the air vent. If air is expected to accumulate during normal operation, please use together with an automatic air vent.
Product Details
| Model | Photo | Connection | Body Material | Applicable Fluids | PMO (bar) | Min. Operating Pressure (barg) | TMO (°C) | Max. discharge capacity (ℓ/min)* | |||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Inlet | Outlet | ||||||||||
| VA1 | | Flanged | Screwed | Cast Iron (FC250) | Water | 10 | 0.1 | 100 | 1400 | Specifications | Manual |
| VA3 | Flanged | Screwed | Cast Iron (FC250) | Water | 10 | 0.1 | 100 | 3200 | |||
| VA4 | Flanged | Cast Iron (FC250) | Water | 10 | 0.1 | 100 | 5600 | ||||
| VA5 | Flanged | Cast Iron (FC250) | Water | 10 | 0.1 | 100 | 11000 | ||||
| VAS |  | Screwed | Cast Iron (FC250) | Water | 10 | 0.1 | 100 | 500 | Specifications | ||
- PMO = Maximum Operating Pressure
- TMO = Maximum Operating Temperature
- The latest version of each product's instruction manual can be found on this page.
*Capacities are equivalent capacities of air at 20 °C under atmospheric pressure