An automatic valve including a valve seat having first gas flow passages extending there through and a valve guard having second gas flow passages extending there through. The valve further comprises at least one shutter member movably arranged between the valve guard and the valve seat, at least one set of spring members biasing the at least one shutter member towards a closed position in sealing engagement with the valve seat to close the first gas flow passages, and at least one spring holder ring provided with a plurality of spring retention seats. Each spring member of the set of spring members is partially housed in a respective spring pocket formed in the valve guard and retained in a respective one of the spring retention seat.