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Netflyer 11-03-2009 05:57 PM

Heat of Fermentation
 
If you have a yeast that has a spec. of 65 to 75 degrees, that is the heat of the fermenting wort right? The heat fermentation generates counts right? So if the room is 70 and the fermentation is occurring at 74 I'm not at the middle range but instead at the upper range of those yeast, regardless of the room temp, right? I mean granted after 72 hours and the vigorous fermentation ends the temperature drops back to 72 and w/in a week it is at ambient temp. So, what do you state the fermentation temperature as being?

Pitch at 70, warms to 74, back to 70 (ambient) after 1 week. Keep it in the fermentor for another 2 weeks at 70. Do those 2 weeks count and figure in to the fermentation temp, or do you just consider those few vigorous days when stating the fermentation temp?

Thanks!

Hammy71 11-03-2009 06:26 PM

Sometimes I have to keep my fermentation fridge at 63 to keep the fermentation at 68.... The temperature range for the yeast isn't the ambient temp, but the fermentation temp. Most of your off flavors from the high temps is from the fermentation cycle itself. After fermentation is complete the ambient/fementation vessel temp is of less importance. So, I try to make sure I control the temperature during the fermentation (usually the first week...sometimes longer). After that I move the carboys outta my chamber to make room for more..

Netflyer 11-03-2009 08:43 PM

Thanks for the reply, I really need a fermentation fridge!

chefmike 11-03-2009 08:54 PM

Or a big tub of water... which will help control fluctuation in temps (think thermal mass) especially if you drop in a frozen water bottle or two.

Netflyer 11-04-2009 01:55 AM

Yes, very doable... so what has been your experience, in say a 65-68 ambient basement, how cool will a tub of water with a few frozen water bottles in it keep the fermenter?

I'm usually running up to 72-74 w/heat of ferm. will water and ice keep me at 68ish? I can pitch at 68 easy...

Palefire 11-04-2009 03:05 AM

Quote:

Originally Posted by Netflyer (Post 1653847)
Yes, very doable... so what has been your experience, in say a 65-68 ambient basement, how cool will a tub of water with a few frozen water bottles in it keep the fermenter?

I'm usually running up to 72-74 w/heat of ferm. will water and ice keep me at 68ish? I can pitch at 68 easy...

My house usually has an ambient of 68-70 (according to our thermostat, anyway). With a swamp cooler (tub of water+t-shirt draped over the fermenter) I can get and maintain pretty much any temp from 60-70. It takes a little bit of practice to learn how many frozen water bottles you need in the water and how often you need to change them to maintain a certain temp, but overall the system works great.

So, yes, water and ice should very easily keep you at 68ish. My guess is that the first time you try you'll add too many frozen water bottles, and when you check a few hours later you'll be shocked to see how low the fermentation temp is (that was my experience, at least!).

Netflyer 11-04-2009 01:32 PM

I'm brewing an Fuller's ESB clone this weekend and the Wyeast 1968 would love 65-68. I'm going to go for it with the swamp cooler, thanks for the advice/help!

If the ambient of the room is at 64-65 and I'm using a standard 'ale pale' 6.5 gal. fermenter and I pitch at 68 do you think room temp water in that 64-65 range will hold her, or maybe just a few ice bottles? Does the water have to be significantly colder than ambient?

winstonofbeer 11-04-2009 03:21 PM

By house is at 73 upstairs...Basement around 70.


Before i got my ferm chamber going, I went to wally world and got me a tub a little longer than 2 carboys. was like 12 bucks. Fill h20 in the tub bout inch-2 deep.

Throw 2 water bottles in " 16.9 - 20oz works great " Check temp in 2 hrs. It should drop your carboy down to about 65-67.

Change out water bottles morning and night for the first 4 days usally, basicly till ferment stops..Then the cold water will keep the temp down.

IF the temp got to high during the active fermentation, I would take the shirt and just dunk it in the h20 and that seems to help a bit.

There is a downside to this, After everything is done...You have a tub full of water you have to take care of..... Dont forget it one day when your in a hurry and leave it in the walkway and your swmbo goes down to the dark basement and steps in ice cold water.....:mad:

Hope this helps

Netflyer 11-04-2009 03:51 PM

Swamp Cooler
 
Quote:

Originally Posted by winstonofbeer (Post 1654807)
Fill h20 in the tub bout inch-2 deep.

2" deep? I was thinking deeper. I'm clueless..:drunk:

So then, this is the picture I have in my little head..

1. Take my rubbermaid bucket and put in 2" of water.

2. Put a tee-shirt over my fermenter and put it in the tub w/the water.

3. Drop in a few plastic soda bottles with ice in them...

4. Change bottles 2x a day

Do I have it?

Palefire 11-04-2009 04:16 PM

Yep, although I usually put a bunch more water in the bin, about 3 gallons' worth. I usually pour into the bin whatever sanitized water I've used on brew day (some sanitizer keeps mold from growing - or at least that's my sense; I could be wrong), the ice water I use from my pre-chiller, and then some more water to reach ~1/3 - 1/2 way up the fermenting bucket. Toss some frozen water bottles in and you're good to go.

You'll figure out what works for you after doing it a few times, but I think you've got the general idea.


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