Recurring verdigris on IC

[BadWolfBrewing]

I built a rib-cage style IC out of 40 ft of 3/8 copper tube, a few copper straights, and weat on elbows/unions. All of this went fine, and there are no leaks.

However, I have a problem with verdigris (blue/green spots on copper). There wasn't any when I built the IC, but a few days later a couple spots appeared so I boiled it in a strong vinegar solution. Came out looking like a shiny new penny, with no verdigris or other oxidation.

Couple days later, same thing happened, but this time I made sure to rinse and dry the copper after the acidic vinegar wash.

Last night, I noticed a couple blue/green spots, so I soaked in a double strength star-san solution (which worked amazing). After rinsing and drying well, I put it into a 350 degF oven for 10 minutes. This was recommended in the Jon Palmer book:

http://www.howtobrew.com/appendices/appendixB.html

This built up fairly thick layer of stable oxide (I hope). Came out a deep orange / ruby. No verdigris this morning, but I'm still nervous.

Has anybody had problems with recurring verdigris? I'm in Wisconsin, so I can't imaging it is the sea water...

How should I be washing / storing the chiller?

Thanks guys and gals

 

[BadWolfBrewing]

actually, it was in this article about baking copper:

http://***********/stories/projects...d-it-yourself/1149-metallurgy-for-homebrewers

 

[BadWolfBrewing]

brewing soon, so I need to bump my own thread...

 

[Coldies]

I have only cleaned my IC once and it was when I first built it. When I brew I pop my IC in the boil for 5 minutes and after it gets hosed off with water and wiped down with a paper towel. I have never had any issues with off flavors that I can detect that would be caused by this. I also live 2 miles away from the beach if it helps.

 

[rcrabb22]

Yes I had issues with verdigris with my copper HERMs coil. It would clean off with similar methods you described but kept coming back. I always had to clean it before every brew day. I gave up on it and replaced it with a stainless steel coil. The copper coil has been gathering dust in the basement ever since.

 

[OneHoppyGuy]

Put it in a StarSan solution for 5 minutes and ZING!!