BOM item: One-way valve


In the BOM in tab ‘KITS’ there is an item called: “one way valve” which has the following description:
allows carbon dioxide to flow towards the chamber, but nothing into the bioreactor
Can anyone explain what it really it for ? Maybe a image on how it is supposed to be implemented ?
And do I need to order 4 of them (as they are packed as single items here at )

Thanks !


It allows the CO2 produced by the fermenting yeast inside the bottles containing a water and sugar solution to flow into the grow chamber,
The way you use it is you connect a tube through a hole on the bottle cap, the other end of that tube to one side of the one way valve (in a way that it allows flow from the bottle to the other side), then you connect another tube to the other side of the valve, end the other end of it you put inside the chamber through a hole on the pvc board.

I think it’s used because once you close the bottle, the yeast will consume all the oxygen inside for reproduction. Then while it ferments the sugars, it generates CO2. If you didn’t use the one way valve, oxygen would keep flowing inside the bottle, and allowing the yeast to perform reproduction instead of focusing only on fermentation.


Thanks Mateus! That explains a lot !
So I only need 1 valve then…:+1:


One valve for each bottle. I don’t know if they use three or four. I’m using three.


Wait… Three CO2 bottles?


I don’t think you really need the one way valve. You can also use a small bottle filled with water to make a one way valve. This way you also get the benefit of seeing the bubbles and detecting that the system is (still) working.

If you want to crank up you biogenerator you can of course hook up more bottles: