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Fermentation Swamp Cooler Temperature Variance

I know we’ve discussed this topic, maybe ad nauseum, in the past but new information has come to light for me.

I ferment all my beers including lagers in swamp coolers and have always been pleased with the results. Maybe that’s all that matters but…

My stick on fermometers are getting kind of old and hard to read so recently I’ve been using the thermapen to check the swamp cooler water temp and just figure the beer in the bucket is within a couple degrees of that. This morning I decided to check the beer since I was going to pop the lid to see if krauesen was building anyway.

Swamp water was 52 degrees. Perfect lager ferment temp right? Well, I sanitized my thermapen and checked the beer in both buckets…62! WT!!

In the past I think we’ve generally agreed that there could be as much as a 5 degree swing in temp from the fermometer to the inside of the fermenter but 10 degrees?

If I go back to the second line of this post…“always been happy with the results…” Yea but…but…

Any thoughts?

Huh…
So about 1/3 of yer bucket is in the ice bath? Perhaps the 2/3 out is more detrimental than thought? Do you cover with a blanket/towel that is in the ice water too? I won’t even call the thermapen in to question…
Sneezles61

Water level in the coolers is about up to the 4 gallon mark on the bucket and each has 5.25 gals in it. So yea roughly 2/3-4/5s of the beer mass is submerged is colder liquid.

I have not been covering them though I actually have insulated covers I used a few times when I set them up. Just never felt it made much difference in the past.

Wasn’t that Flars method…? and he had a fan blowing on it too…
I tinkered a few times with ice baths… but way back then, I was naive and didn’t know any difference…
Sneezles61

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I used to use a swamp cooler with wet towels. Then I moved to recirculating cold water through a coil when I moved to conicals. Got tired of switching ice bottles and the limiting factors.
I’ve been touting for years that fermentation temps can easily climb 8-10° above ambient. Usually it’s with higher OG beers and ales that usually have a more vigorous fermentation. It does surprise me out of a lager.

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I have just relied on my stick-on thermometers to check temp, I adjust the ice in the swamp cooler to keep that in the range I’m looking for and the sticker stays above the swamp cooler water line. Now you’ve got me curious. . .did you ever compare temp in your swamp cooler to temp on the sticker and temp of the wort? I typically only have about half the beer submerged in the swamp cooler.

:beers:
Rad

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Yea this is frozen bottles in igloo cube coolers and has worked fine. Maybe I shoudn’t have checked with the thermapen…haha

Actually I should grab some new fermometers. Mine are too difficult to read now but if I shine a light on one and squint it appears to agree with my thermapen reading of the wort. I figured it had balanced out with the swamp cooler water more closely after two days.

I never trusted those stick on thermometers. Don’t think they are very accurate

As long as they’re consistent they don’t really have to be all that accurate though right? My only reason for posting this is to point out that just MAYBE the temperature range of yeast is much more flexible than we may believe. I mean, if I’ve been cranking out decent lagers at a significantly warmer temperature than previously thought, that’s good to know. I know a few bigger local breweries, like Old Ox have been marketing a lager yeast that they claim works fine in the 60s(F).

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I’d love to see a graph of temp over time with a Tilt in a swamp chiller.

I mean I’m a gadget hound, so I’m not getting rid of my temp-controlled freezer. But I also say all that temp control was the best thing that ever happened to my beer quality. It would be nice to know how good swamp chillers can be. (And I do believe they can be good)

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I’d rather not. Haha

But yea they can be very consistent if you stay on it. Frozen bottles twice a day generally keep the bounce within about 2 degrees.

I have all the materials to build a temp controlled fermentation closet. The last couple batches and dealing with the frozen bottles is finally enough incentive to get that done this week.

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THIS IS ABSOLUTELY CORRECT! Within reason. 50° v 52-54° ain’t gonna make a difference. And yea there are some lager yeast that can ferment warm (34/70) though I keep it cool!

Yes, in the summer, I swap out ice before I leave for work and after I get home from work. In peak fermentation, I will occasionally do a third change before going to bed, keeps pretty consistent for me.

:beers:
Rad

I feel your pain with the swamp coolers …I did that for a while. We’ve got a crazy, probably expensive for the electric bill, amount of refrigerators here. I have a dedicated fermigerator as a result. It’s an ancient Frigidaire refrigerator that I got from a neighbor. He was actually a delta force colonel that was retiring to work inside the beltway in DC. The buyers of the house managed to pi$$ them off and he comes over and says do you want a fridge? It was apparently supposed to convey. That was 1994. He was a great neighbor, he always met me outside with a beer.! He would do the old, if I told you what I did for a living I’d have to kill you shtick all the time.

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Yea I’m at the end of my rope with the swamp coolers. I have enough things to deal with lately. I need to make fermenting a lot less labor intensive. Gotta get down to building my cold closet this week.

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Now why is it, this post just showed up? Maybe I chatter too much and the forum knows?
If I had to do my freez-mentor over, I’d opt for an upright… Keep it on wheels so you can push it out of the way… or where you are brewing… The way my fermenters are configured, I could fill it in there and push out the brew in there… Eliminate lifting…
So this brew I’ve got in there right now, I set it at 52F… My tilt showed a few times, 58F… and that is on the second round with the yeast cake… Perhaps more yeast, it does get a bit warmer?
Sneezles61

Will a conical fit in an upright? I have an upright that i can get but have been holding off. The chest gives me extra counter space

I would see what the diameter is, make a cardboard disc that size and see if it fits… My fermenter is very close to a 5 gallon bucket…
Sneezles61

Probably depends on the freezer size and the conical. My 16CF upright holds six kegs, could probably get 3 maybe three buckets in there. That’s with all but the top two shelves removed from the door.

Hi guys. I’m prob getting way ahead of myself as I haven’t brewed the batch I’m worrying about😂 I’m brewing my first alt bier in the next 2-3 days. I am out of town for the last week of fermentation and using swamp coolers (also a first) to keep within the proper temp. My basement holds a semi steady 65-68 degrees, was planning on moving it down there while I’m gone and probably adding a few extra frozen water bottles. Does this sound like it would make sense? Just a little worried about leaving my precious beer all by its lonesome. Thanks

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