Cleaning a counterflow chiller

jeffpn

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I'm still working out my issue of my bottles becoming overcarbed at the 3-4 month mark. I won't have an answer until around March. For my last 3 batches, I've used my immersion chiller. I'm testing my theory that my counterflow chiller is contaminated, and able to survive my soap/bleach siphon through prior to use. I'm thinking about siphoning boiling water through it, prior to using it today. Would that kill any algae, mold, or any other contaminants found inside the 23' coil? Would the exiting water still be hot enough to kill anything on the far end? Has anyone ever done that before? After doing that, I would still siphon soap/bleach through it.
 
Sounds like a reasonable hypothesis to me. If they're overcarbing that late, some infection at a very low level is likely getting in. Problem is you might have some crud stuck somewhere in a fitting, a hose, the chiller. And if you have crud, sanitizer or disinfectant won't work because the bacteria can hide in the crud. My advice would be to take everything apart you can and clean and disinfect it. The chiller presents a problem but I'd approach it this way: PBW or even unscented Oxyclean. Pump it through as if you were pumping wort through it. That way, if there's some crud stuck in there, you should get it out and be able to disinfect properly.

Boiling water might work, just think safety.
 
The nice part of the way I built the chiller is that the wort flows through one continuous 3/8" OD pipe. There are no solder joints or threaded connectors to be contacted by the wort. It's too long to run a brush through. I tried doing that. Anyway, it seems I'd rather replace a garage door opener than brew today. I guess the beer has to wait!
 
Could you set it up to recirculate the PBW solution for an extended period of time, as to flush it continuously?
Might help to loosen up the crud.
 
The only thing stopping me from doing that is a lack of a pump.
 
Flushing with PBW has worked well for me. I also run starsan through it right before draining my wort into it.
 
If it's a clean, straight pipe, it's unlikely anything is stuck in there unless there's a kink or other place to accumulate gunk. But now you're into why I like my immersion chiller - no place for gunk to hide, I drop it into the hot wort and forget about it while my whirlpool hops are steeping and voile! A sterilized length of tubing. Try filling it with PBW, then Starsan and you should be taking care of any beasties lurking in there. And if your bottles are still going through slow-motion overcarbing, look elsewhere for a source of contamination.
 
Even though there's no crevices for gunk to hide, I know from my hoses that algae can grow in that environment. Every day at work, the tube that I fill my water jug with has a green spot on it. Stuff like that has to be growing in my chiller. To me, the question is whether I'm killing it prior to use. It's funny, because I am hanging my hat on the chiller being my problem. If it's not there, I just don't know where else to look. Every other part of my brewing I've been doing the same way for 20 years.
 
Algae can only grow where there's light.... But to quote Sherlock: When you've eliminated the impossible, whatever is left, however improbable, must be the truth. PBW it, Starsan it and see if the problem goes away.
 
True, true. I could be suffering from an onset of mold. I believe mold likes cold, damp, dark conditions. I'll probably bite the bullet and try cleaning the chiller like that and using it on one of my next upcoming brews.
 
I stand by my boiling process, Im not sure if you have a pump or not but just boil water in your kettle then pump it through the chiller and back to the kettle in a loop, I run it through my whole system before i brew even the plate chiller, you can set that water aside after done then use it for cleaning later
 
Not sure how your CFC is configured or what you have for wort side fittings. Slowly fill the chiller, while purging air, with a alkaline brewers wash or Oxyclean and let it soak for couple hours, then rinse with 180+ degree water. Rinse again with StarSan you should be good to go. This is what I recommend to my customers and is procedure I use and have had good luck.
 
Debris will loosen up more easily if you back flush using a pump or even gravity. If you can imagine crud growing like a fish scale, it's easy to visualize why going the opposite direction would be more effective. This is true for ball valves as well as chillers.

After I brew I usually run some sanitizer through the cleaned counterflow chiller so nothing will grow while it waits to be used again. I also try to get all the water out of it. The next brew day, I stick it into my kettle while I'm heating water to sparge. Fifteen minutes of boiling seems like enough to do the job. Then I pull it out, drain it and add cool water to get the temperature to the appropriate level. By flame out, it's back to room temperature.

Good luck!
 
The water containment is done by a rubber hose. It's a high temp hose, but I think multiple boilings (over its lifetime) would probably be bad. There are some good ideas in this thread. I'll certainly try some of them.
 
on a rubber hose counterflow shouldn't the wort go through the copper and water around it contacting the hose
 
That's correct. I just don't think it'd be good for the hose to throw the whole thing in boiling water.
 
Mine is all copper so temperature won't hurt it. If you are using a hose, you are restricted to working on the internal pipe.
 
My LHBS has an all copper CFC. It's pretty dusty!
 
after I am done with my brewing, I boil water in the boil pot and run it though the hoses and the chiller both ways to try to get it cleaned out. Sometimes I even do this before I brew also, always worrying about stuff getting stuck in there.
 
After use, I siphon soapy water through mine. I'm convinced it's clean when I'm done. I'm more worried about what takes up residence between uses, due to the dark and damp conditions. Before use, I siphon soap and bleach through it. I'll definitely siphon boiling water through it immediately before my next use.
 

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