OPW FC 623V-3203 3" Pressure Vacuum Vent Manholes Morrison tank vents are designed

Morrison tank vents are designed only for use on shop fabricated atmospheric tanks which have been built and tested in accordance with UL 142

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hydraulics

and (2) compression fittings

levers of complicated sequence leading to valve closure

OPW FC 623V-3203 3" Pressure Vacuum Vent Manholes Morrison tank vents are designedPressure Vacuum Vents are installed on the top of vent pipes from underground or aboveground fuel storage tanks. The vent cap and internal wire screen are designed to protect the tank vent lines against intrusion and blockage from water, debris or insects. A normally closed poppet in the valve opens at a predetermined pressure or vacuum setting to allow the tank to vent. Pressure Vacuum Setting 2. 5" to 6" water column pressure settings and 6" to 10"