Hey brewers, I have leeched so much good information from this forum over the years that I thought it was time to contribute a little something so I thought I'd post the results of a little experiment I did this past week. Like a lot of brewers I have a rig with more than a couple of ball valves on it. I am guessing that like me most brewers don't take apart their ball valves after each brew. I just circulate PBW throughout the system and call it good. This has worked fine for me for years and I have never gotten an infection, at lest not to my knowledge, of course I also circulate boiling wort through the system before chilling as well. Wise men say to CIP with your ball valves half open so that PBW can cover as much of the inside as possible. I also fully operate all of my valves several times each during the process as well as during the clean water flush at the end. Well, I wanted to see what it looks like if you just CIP with the ball valve open and don't operate it at all during the process. I took off two ball valves after my last brew, one that I opened and closed during CIP like normal and the other I just left open. Hopefully these pictures upload OK so you can behold the funk.
Dirty ball valve that was not operated during CIP recirculation
Spotless ball valve that was opened and closed during CIP recirculation as well as final flush.
So the lesson here for all you ball valve users out there is to develop a solid process for your ball valve CIP and do it every time. CIP with your ball valves half open. Also open and close your valves several times during CIP as well as during soak and clean water flush. Hope that helps shed some light on the hidden mysteries of ball valve CIP.