The Flomatic 4701SS 77 1" Auto‑Vac® vacuum breaker is designed to automatically relieve vacuum conditions in piping systems, helping prevent water hammer and pipeline collapse. This valve is commonly installed at high points in wastewater, irrigation, and water tank systems to allow air to re‑enter the line when system pressure is relieved.

Specifications:

Valve Type: Auto‑Vac® vacuum relief valve

Connection: 1" NPT male

Body Material: Stainless Steel

Internal Components: Engineered composite materials

Disc: Stainless steel

Seat: Resilient seat

Max Pressure: 400 PSI

Max Temperature: 180°F (80°C)

Operation: When installed at the highest point in a piping system, the Auto‑Vac® valve automatically opens as system pressure is relieved, allowing air to enter and the line to drain. Once the piping system is refilled, the spring‑loaded valve closes and remains sealed during normal operation.

Construction: The Model 77 features a compact, spring‑loaded design with corrosion‑resistant materials. All internal components are identical across material options, providing consistent performance regardless of body material selection.

Applications: Wastewater piping systems, irrigation and sprinkler systems, agricultural watering systems, domestic water tanks, and other installations where vacuum relief and water hammer reduction are required.

Flomatic Quality: Flomatic Auto‑Vac® valves are engineered for maintenance‑free performance and long service life, using proven designs and materials trusted in water and wastewater applications worldwide.