Automatic Drain Valves


Automatic Drain Valves prevent the accumulation of fluids, condensation, or contaminants in fire lines, standpipes, and other pipelines. When the system is unpressurized, the internal spring tension exceeds the expected static head and the valve opens. This allows fluids to escape and reduces the danger of line freezing, rupture and corrosion. When line pressure is applied, the valve automatically closes and stops flow. All components are brass except the stainless steel Viton covered stem.

Greenwood Valve Catalog




Size: 3/4 in. N.P.T. for static head up to 50 ft.
Pressure: A.N.S.I. 300 lbs.
Overall Length: 3 in.
Overall Weight: 1 lb.

Note: When ordering, specify normal line pressure and height of static column so proper spring tension can be furnished.



No. Part
1 Body (3/4 in)
2 Stem
3 Cap
4 Spring



Automatic Drain Valve Installation



Automatic Drain Valve