Silver Solder in/for Fermenter?

[outside92129]

Are there any issues with using plumbing grade silver solder on (and inside) a fermenter? I just finished my new snazzy fermenter and just noticed what looks like oxidation on the solder. It's light gray, powdery, and comes off with the slightest touch. Would this be a simple case of Bar Keeper's Friend?

p.s. i'll post pics and info once i test out the design of the fermenter.

thanks!

 

[Bensiff]

I don't know what would cause that with solder unless its just excess solder that flowed onto areas that did not have flux.

Solder does not hurt anything in my experience...I have used soldered copper manifolds for my mashtuns for years without any negative effects that some say that can happen. I don't think enough of it can leach during a brew to be an issue.

 

[outside92129]

I called the solder company (Oatey) and the flux manufacturer (Lennox) and what's happening is that some residual flux is causing the solder to oxidize. Stainless steel flux is very acidic and what i'm seeing is tin oxide. New flux can be used to wipe off the old gummy/burnt flux with a rag, but the inside of the fermenter cannot be reached. Both companies recommend flushing unreachable areas with hot water to get out all the old flux.

 

[rekoob]

I called the solder company (Oatey) and the flux manufacturer (Lennox) and what's happening is that some residual flux is causing the solder to oxidize. Stainless steel flux is very acidic and what i'm seeing is tin oxide. New flux can be used to wipe off the old gummy/burnt flux with a rag, but the inside of the fermenter cannot be reached. Both companies recommend flushing unreachable areas with hot water to get out all the old flux.

Good info to post. Thanks. I wipe everything pretty good and had one joint do this to me after doing a leak test with water up to mash temps. I cleaned the heck out of it and did the water/burner thing again just to see what would happen. It was nice and clean afterwords. I guess I didn't get the flux off the first time, and it is a pain to get off, not sure hot water will do the trick but I would guess they know what they are talking about.

Good luck.