Angel's check valve?

[Mr. Tact]

I started playing Sea Block and I've never used Bob's or Angel's mods before. I have a situation where I want a inserter to work only if the supply of gas is below 75% capacity or so... I thought a check valve would allow me to do this. And it probably will, I just don't understand how. Basically the inserter will start a process that produces the gas... how do I do this? The valve's value is around 900.. so I am guessing it also acts as a mini buffer? I've done belt and chest capacity checks before, but this doesn't seem to be clicking.

[Arch666Angel]

The valves are basically small 1x1 storage tanks with modified fluidboxes, so for what you have in mind just hook the check valve up to the circuit network and connect it with the inserter. It can store 1k fluid (the tooltip is wrong there), so your condition should be: anything < 750