[rb30022]

I use Star San as my sanitizer of choice.  I recently purchased a copper counterflow wort chiller and added it to my system.  After using it for the first time, I flushed it with hot water and then ran Star San through it.  I decided to leave it full of Star San to prevent anything from growing inside between brews.  A few weeks later, I was reading an article on cleaning and sanitizing and was reminded that Star San is an acid and that it reacts with copper.  I removed the hose from the bottom of my chiller and allowed it to drain and, sure enough, it has a green coating on the inside.  I have a couple of questions regarding what damage I may have done.

1.  Is the green stuff inside my chiller harmful to humans and, if so, how should I go about removing it?

2.  Have I done any permanent damage to my chiller such as pitting that might allow bacterial places to hide?

Thanks for any help or suggestions.

[Brutal Eric]

That same thing happened to me. After that I lost faith in reverse wort chillers. Went back to immersion. Vinegar and baking soda paste, however typically you wipe away???

[chumley]

I would run a hot Oxyclean solution through it, then flush again with warm water.  No, it is not toxic, but....IT MAY OXIDIZE YOUR BEER! 

Store those things dry.

[Saccharomyces]

A counterflow chiller is self-sanitizing.  All that needs to be done is to keep it free of organic matter.  Clean and drain the chiller after use (use an alkaline cleaner like Craft Meister Alkaline Brewery Wash).  Flush the chiller with hot water before use and allow boiling wort to drain through it until the entire coil is at at least 160F (flash pasteurization temperature).  If the temperature at the outflow is at least 160F, the coil is at least 160F.  At that point, shut the outflow off from the chiller for a minute before turning on the cold water supply and allowing hot wort to flow through the chiller.  It does not long to kill the vegetative cells of the microbes that spoil beer.