After every brew session I always flow hot water in both directions and then repeat with oxyclean/PBW followed by a quick starsan rinse. I felt it was coming clean. Tons of gunk would come out, but lately I felt it was taking longer to chill. The chiller is a Duda Diesel B3-36A-40ST.
I baked the chiller at 500f in the oven for an two hours. Stank up the house and a small amount of dark stuff came out the the wort entrance/exit.
I loaded the kettle with five gallons of hot water and pbw. Started heating and circulating at the same time. the pbw solution turned black very quickly. I recirculated for about 20 minutes at near boiling temps. Dumped that solution and then repeated with a fresh hot pbw rinse. This again turned black. Repeat. Repeat. Repeat. Repeat. Six freaking times. It takes longer every time for the hot pbw to darken but it always gets there, including a small pile of debris is in the center of the pot. I’m reversing the flow every time. I’m going longer with my flushes, I’m up to about an hour at a time now.
Other than caustic. Does anyone have other suggestions for cleaning this junk out?
If you don’t have some sort of fine filter at your kettle inlet, you have probably been pulling debris into the chiller that lodges in between the plates. I have a length of stainless hose braid over a slotted copper intake pipe that seems to do a decent job of keeping larger debris out of my wort flow.
But even with that, I find that I still have to ALWAYS reverse flush and I have to perform a hot PBW recirculation cycle to dissolve and breakup the crud and wort sugars that plate on the stainless chiller plates occasionally. I’d say I perform the hot PBW recirc about every third brew. My system is RIMS, so its easy to bring a batch of recirculating PBW to temp along with the hot water rinse that follows.
Yep. I reverse flow with water and PBW every time. Just not with really hot water. I’ve had a couple of really dirty batches recently that I think have made this worse.
I don’t have a filter over my intake though.
My main concern right now is getting it clean enough to brew with.
I do a CIP cycle before my brew day and have never had troubles with contaminations or anything. I use a caustic solution at 70C and recirculate for 10 minutes, then I use an acid solution at 60C for 10 minutes and lastly I do a recirculation with peracetic acid at room temperature for 10 minutes.
I had the same issue with my plate chiller. Emailed the manufacturer and they sent me a pretty detailed process for cleaning. Here is the jist from Duda for my chiller…
As far as cleaning, backflushing with boiling water, and then using starsans before a brewing day to sanitize are our preferred methods. There are of course many other methods, but the rest seem to have both pros and cons:
PBW - I love PBW. Does a great job cleaning, but doesn’t sanitize like starsans will. This is a good option if your filter didn’t do a good enough job, or if you don’t want to flush with boiling water.
Starsans after a day, rather than before for sanitizing - no point in this. Starsans won’t clean as well as PBW will, and the risk you run into is some people like to let the exchanger just soak in starsans. Seeing as starsans is mildly acidic, this isn’t good for the long term life of the exchanger.
Lye solution - this is actually the method I prefer, submerging the exchanger in water and lye, but it is technically not recommended. The lye water will clean and sanitize better than any other chemical out there, but it can do some very minor damage to the chromium coating on the stainless steel, taking away a layer of its protection from corrosion. So you might have to replace the exchanger after 20 years if you go this route. This is also a much more dangerous chemical than the others mentioned, you want proper hazmat gear for this method. But its still the way I go, because the cleaning is second to none.
Baking - throw the unit in the oven, 400 degrees for 3 hours. This is my boss’s preferred technique. No chemicals involved, absolutely sanitizes, burns out anything caught inside, and removes any fluids from inside the unit. My objection to this method is that some types of trub, if already inside, can get cooked into the unit and make things worse. “
You’ve more then likely carbonized all the internal deposits during the 500f baking. The good news is there isn’t anything living in there anymore that can infect your beer. The bad news is that carbon is insoluble in anything you would want to put in there to dissolve it. NaOH would have worked quite well on the gunk before it was baked into carbon. Now all you can do is just keep flushing and hope the mobile material is dislodged and flows out and not worry about the rest as they will settle out in your fermenter.
I’ve completed ten rinse cycle with very hot (160f+) PBW. The last two did not get nearly as dark. I’m thinking probably two or three more should do it.
I’ve only ever seen caustic and PAA at breweries. Where can you get it as a Homebrewer?
I have a Blichmann plate cooler that’s nearly 7 years old and has never had any issues. That said, I have always used hop sacks (muslin bags) to contain my hops additions. I can install an inline filter, but that seems to me like an additional and unnecessary cleaning step.
My post brew cleaning regimen consists of a back flush of 140° water followed by a 60 minute circulation of PBW followed by a second back flush of 140° water. Then I remove the cooler and allow it to fully drain overnight before reinstalling it. Then, on brew day, I circulate IO-Star for about 45 minutes before use.
And, while I’m certain I don’t get the same effectiveness from my hop additions, I simply changed my Hop Utilization factor within my BeerSmith software to 90% and all is good.
I agree with Bilsch - 500°! That may have caused more harm than good, IMHO. Good luck!
My routine for cleaning my Blichmann plate chiller has been immediate backflushing with hot “DIY” PBW and warm water rinse. Immediately prior to the next brew session, I steam sterilize in a regular pressure cooker for ~30 min immediately prior to next brew – the chiller fits in it just right. The chiller still gets starsan as part of the tubing sanitization. This protocol has been pretty effective for me.