4" Aluminum Air Release & Vacuum Relief Vent – Simple Action FNPT
was
$301.48
Special Price
$139.18
4" simple-action aluminum air release and vacuum relief vent — the largest size in the series, designed for high-capacity commercial irrigation mainlines. Automatically expels large volumes of trapped air during system startup and admits air during shutdown to prevent vacuum damage. Cast aluminum body is lightweight relative to steel alternatives. Rated to 100 PSI with a 10 PSI sealing pressure.
| Size | 4" |
|---|---|
| Connection | FNPT |
| Valve Action | Air Expulsion & Admission |
| Max Pressure | 100 PSI |
| Sealing Pressure | 10 PSI |
Availability:
In stock
SKU
RKARV-400
Ships Same Day
All orders placed by 12 PM local warehouse time will ship the same day. Some exclusions apply. Delivery time may increase if item isn't available in closest warehouse.
Delivery time: 2-4 business days
RKARV-400 – 4" Aluminum Air Release & Vacuum Relief Vent
The RKARV-400 is the largest simple-action aluminum air vent in the series, purpose-built for high-capacity commercial irrigation mainlines. Its 3.4" clear opening diameter provides maximum air flow for rapid evacuation of trapped air during system startup, and it automatically admits air during shutdown to prevent vacuum-induced pipe collapse.
Key Features & Benefits
- Dual-function operation — expels air during filling and admits air during drainage to prevent vacuum collapse
- 3.4" clear opening diameter — the largest in the series, handles maximum air volumes for fast startup on high-capacity mainlines
- Cast aluminum body — significantly lighter than steel alternatives for easier mounting at pipeline high points
- Corrosion-resistant construction — withstands outdoor agricultural environments season after season
- Synthetic rubber seal — ensures positive sealing at 10 PSI sealing pressure
- Simple, reliable design — no complex moving parts means trouble-free performance with minimal maintenance
Why Air Vents Matter
On large-diameter mainlines, trapped air pockets are a serious operational concern. They reduce flow capacity, cause pressure surges (water hammer), lead to inaccurate flow meter readings, and can damage pipes and fittings. Install 4" air vents at all high points on your mainline to ensure efficient, reliable system operation.
Materials & Construction
- Body: Aluminum
Download Specification Sheet
Dimensions - Inches
| Size | Nominal | Clear Opening Diameter | Height | Width | Weight |
|---|---|---|---|---|---|
| 1" | 1 | 0.7 | 4.2 | 2.2 | 0.55 lbs |
| 11/2" | 1.5 | 1.2 | 4.9 | 3.3 | 1.16 lbs |
| 2" | 2 | 1.9 | 5.8 | 3.4 | 1.65 lbs |
| 3" | 3 | 2.6 | 7.9 | 4.9 | 3.63 lbs |
| 4" | 4 | 3.4 | 9.8 | 7.1 | 6.72 lbs |
Dimensions - Millimeters
| Size | Nominal | Clear Opening Diameter | Height | Width | Weight |
|---|---|---|---|---|---|
| 1" | 25.4 | 17 | 106.5 | 55 | 0.55 lbs |
| 11/2" | 38.1 | 29.5 | 123.5 | 82.5 | 1.16 lbs |
| 2" | 50.8 | 48 | 145.5 | 88 | 1.65 lbs |
| 3" | 76.2 | 64.5 | 200 | 124 | 3.63 lbs |
| 4" | 101.6 | 87 | 247.5 | 180.5 | 6.72 lbs |