Fig. No. 669 Tank Breather Valve

The 'ROMA' Fig. 669 Pressure/Vacuum Breather Valve is a dead weight loaded disc relief valve.

The valve body is designed to accommodate a weight loaded pressure relief disc to lift at a pre-determined pressure to discharge to atmosphere, and a dead weight loaded vacuum relief disc to lift at a pre-determined vacuum and admit air to a vessel.

The pressure and vacuum disc assemblies are weighted to relieve at the specified pressure and vacuum.  When the lift-off pressure or vacuum is reached the valve will open with only a small accumulation in pressure or vacuum.