Trumbull Floor-Type Pressure Relief Valves (PRV) are cast in the bottom of tanks of treatment plants to keep empty tanks from floating from an excess of groundwater beneath them. When this condition occurs, the hydrostatic pressure will open the cover of the valve allowing water to enter, thereby equalizing pressure inside and outside the tank and preventing it from floating. They will start to open at less than one foot of head. Lugs in the body prevent the cover and strainer from becoming separated from the body of the valve due to flow. Both can be removed when necessary, however, by turning to the right or left.

Our valves use two Neoprene seating surfaces so that if particles of grit lodge on them, the head of liquid in the tank will force the valve closed, preventing seepage of liquid into the ground. These valves are for low seating or unseating pressure applications only. Improved design uses C900 pipe gaskets in bell to securely retain PVC pipe to valve.

Trumbull also makes Wall-Type Pressure Relief Valves, shown HERE, for installation in side walls of tanks.

Floor-Type Valves are cast in 4″ and 6″ sizes, in overall lengths of approx. 7-3/4″. The lengths can be extended by inserting C900 PVC pipe into the underside of the valve. The PVC extensions can be furnished and inserted by Trumbull to customer’s exact length requirements, or in the field with customer suppied PVC pipe.

Unique square design of our QuadroSeal™ Gasket surrounds casting on FOUR SIDES to prevent separation. This design also prevents metal-to-metal contact that can cause seating surfaces of iron valves to corrode into a “frozen shut” position. PDF information sheet shown HERE.


Size DOMESTIC Item No. NON-DOMESTIC Item No. Weight
4" 1367-1558 367-1558 13.20 lbs.
6" 1367-1559 367-1559 23.10 lbs.

Ductile iron models furnished with NSF-61, 2 part epoxy coating.


Size DOMESTIC Item No. NON-DOMESTIC Item No. Weight
4" 1367-1540 367-1540 14.50 lbs.
6" 1367-1544 367-1544 22.30 lbs.