APPARATUS AND METHODS TO DISPENSE FLUID FROM A BANK OF CONTAINERS AND TO REFILL SAME

摘要

A dual check valve device has a housing, a first check valve in the housing and a second check valve located in the housing adjacent the first check valve. The dual check valve is suitable for use in a cascade system includes a manifold having a fluid outlet port to dispense fluid and a fluid valve engaged to the manifold. First and second fluid storage containers are coupled to the manifold. The fluid valve is configured to control a first fluid flow path between the second fluid storage container and the fluid outlet port.