PVC vs CPVC valves on fermenter question

[ThreeDogsNE]

I'm setting up 15 gallon plastic conical fermenters with valves, and found that the 3//4" CPVC ball valves at my local Menards look dubious. The other local big box stores do not have 3/4 inch CPVC valves. Is there an issues with using PVC valves under a conical? They would never face temperatures higher than room temperature, unless I really get ambitious fermenting a saison and subject them to 85*F. They would see 5+% alcohol concentrations. Search shows me a lot about using PVC in mash tuns, but this use would never get as warm as the mash tun. Is there a good reason why I should avoid using them under the conicals?

 

[_JP_]

I don't see why not. If it were me, I'd use the PVC.

 

[Germelli1]

I am in the same boat as you. I would be more worried about pH then temperature, but I am not a chemical engineer so I have no idea

 

[AiredAle]

You'll be fine. The valves don't have any plasticizers in them to leach out, and the temps are low and exposure to the valve body is low, if there were anything nasty to leach. I am an organic chemist and have worked with rubbers, plastics and adhesives for over 30 years. pH isn't an issue until it gets high (strongly basic) then it can attack the chlorine atoms on the polymer chain. If you soak the valves in hot beer line cleaner (potassium hydroxide) or the like, you might have an issue, but at fermentation temperatures and pH (4 to 6) no problems.

 

[Germelli1]

You'll be fine. The valves don't have any plasticizers in them to leach out, and the temps are low and exposure to the valve body is low, if there were anything nasty to leach. I am an organic chemist and have worked with rubbers, plastics and adhesives for over 30 years. pH isn't an issue until it gets high (strongly basic) then it can attack the chlorine atoms on the polymer chain. If you soak the valves in hot beer like cleaner or the like, you might have an issue, but at fermentation temperatures and pH (4 to 6) no problems.

Thanks a ton for the explanation! You have helped put my mind and wallet at ease in building a conical!

 

[ThreeDogsNE]

You'll be fine. The valves don't have any plasticizers in them to leach out, and the temps are low and exposure to the valve body is low, if there were anything nasty to leach. I am an organic chemist and have worked with rubbers, plastics and adhesives for over 30 years. pH isn't an issue until it gets high (strongly basic) then it can attack the chlorine atoms on the polymer chain. If you soak the valves in hot beer line cleaner (potassium hydroxide) or the like, you might have an issue, but at fermentation temperatures and pH (4 to 6) no problems.

Thanks very much! This is just the kind of expertise we find hanging around on HBT that makes this place great! My bachelors in chemistry 30 years ago makes the language familiar, but I am no more fluent in that than in the French classes I took back then. I was hoping to find expertise like that here. Thank again!