Fermentation Chamber Question

[widgetjam]

I'm planning on buying an old CL chest freezer then installing a dual temp controller. I've read that attaching the probe to the side of the carboy or directly into the wort yield more accurate results. My major question is how to go about adding another beer into the fermentation chamber when I already have a beer in there fermenting. Obviously putting the probe on/in the new warmer beer will cause my already cool beer to lower since the chamber will be trying to cool the new beer. Would it just be better to keep the ambient temp of the chamber at ~60* to accommodate any new beer additions? I plan on mainly brewing with American and British Ale yeasts as I'm still trying to get a strong handle on malt/hop use in my beers. Thanks for any insight!

 

[alane1]

How often do you brew, and how long do you ferment before bottling? If you're ready to brew again after 2 weeks of primary I don't think a lower temp swing for the new batch would affect the fermented batch since the yeast is probably done doing it's thing. I would also move the probe to the newer batch.

 

[SeeMont]

This has always bothered me. It takes a long time to affect temperature change in a 6 gallon carboy. The chamber is only controlling the air temp only and this only touches the outside of the container. I have room for two carboys in my chamber and just have the temperature probe in a small bottle filled with water, this seems to work just fine. Then maybe I am doing it wrong.

 

[unviewtiful]

This has always bothered me. It takes a long time to affect temperature change in a 6 gallon carboy. The chamber is only controlling the air temp only and this only touches the outside of the container. I have room for two carboys in my chamber and just have the temperature probe in a small bottle filled with water, this seems to work just fine. Then maybe I am doing it wrong.

This method is likely more accurate than measuring ambient, but it does not account for the heat generation during the fermentation process. A thermowell or taping the probe to the side of your fermenter with some insulation will allow your chamber to adjust when the yeast is most active.

 

[kanzimonson]

First comment - put a towel or some kinda wrap around the carboy so that the probe is a little more insulated from the air.

On to your problem - is it possible that your brew schedule aligns so that the first beer is already in a finishing stage, and can be brought out of the chamber to use ambient or added heat to finish the beer?

Next solution, and I'll admit I've never tried this. It will be finicky and difficult to get correct, but I bet you could wrap a heating device around the first beer, wrap it in some insulation (towels), and then attach the probe to the second beer, also wrapped in a towel. Sure, the controller would be "focused" on the 2nd beer, but you could probably keep the 1st in a reasonable temp range.

 

[b-boy]

First comment - put a towel or some kinda wrap around the carboy so that the probe is a little more insulated from the air.

On to your problem - is it possible that your brew schedule aligns so that the first beer is already in a finishing stage, and can be brought out of the chamber to use ambient or added heat to finish the beer?

Next solution, and I'll admit I've never tried this. It will be finicky and difficult to get correct, but I bet you could wrap a heating device around the first beer, wrap it in some insulation (towels), and then attach the probe to the second beer, also wrapped in a towel. Sure, the controller would be "focused" on the 2nd beer, but you could probably keep the 1st in a reasonable temp range.

My ferm chamber does a variation of this.

I have 2 controllers.

One powers the freezer and acts as my main control. I use a thermowell in a carboy most of the time. Generally I keep the chamber at the same temperature, even with multiple beers fermenting at the same time. I usually ferment ales in the low 60s.

If I want to do a special beer, that needs to ferment higher, I use the second controller. It powers an outlet inside the chamber. I plug in a ferm heat wrap and use the controller and another thermowell to turn the ferm wrap on and off. The ferm wrap is wrapped around the carboy and heats the carboy.

Overall it works pretty well. I don't think it can raise the temp more than ~10F, but that works for most beers except Belgians. I could probably use a heating pad and get even better results.

 

[joshesmusica]

yeah it seems like your ferment schedule is, well, fun! what are your ambients outside the temp controlled chamber? if the first beer is past 5-7 days, it's likely you could just take it out of the chamber, granted that the ambient temps outside aren't above, oh, i don't know, let's say like 80F.

 

[widgetjam]

My ambient temps inside the are ~75F in the summer (A/C on all day since is usually 100+ degrees outside) and high 60s the rest of the year. So would keeping the chamber in the low 60s just be my best bet for decent fermentation or is that counter intuitive to having the ability to control your temperature in the first place?

 

[joshesmusica]

if you're staggering brews to where the first brew hasn't finished the most vigorous part of fermentation, then you're a really lucky guy!

the main time to worry about ferment temps is during the first 5-7 days. after that it's still important to maintain a fairly constant temperature (aka not swings of 10F from morning til midday then back down again at night), but you can allow it to rise up to ambient 75F until cold crashing it, or until bottling. in fact a lot of people intentionally raise the temperature of their chamber after those first few days in order to ensure full attenuation (as far as the yeast will go) and to encourage the yeast to clean up after themselves.

what is your brew schedule like? if it's every week (or anything less often than that), then just take the first fermenter out when putting the second fermenter in. if it's more often than every week, then i would try to get the brews within 1 day of each other and keep the temp probe on the first beer until activity started to slow a bit, and then move it to the second beer.

 

[widgetjam]

if you're staggering brews to where the first brew hasn't finished the most vigorous part of fermentation, then you're a really lucky guy!

the main time to worry about ferment temps is during the first 5-7 days. after that it's still important to maintain a fairly constant temperature (aka not swings of 10F from morning til midday then back down again at night), but you can allow it to rise up to ambient 75F until cold crashing it, or until bottling. in fact a lot of people intentionally raise the temperature of their chamber after those first few days in order to ensure full attenuation (as far as the yeast will go) and to encourage the yeast to clean up after themselves.

what is your brew schedule like? if it's every week (or anything less often than that), then just take the first fermenter out when putting the second fermenter in. if it's more often than every week, then i would try to get the brews within 1 day of each other and keep the temp probe on the first beer until activity started to slow a bit, and then move it to the second beer.

This seems like the best thing to do so far. I might just do two consecutive brew days with similar temp ale yeast. I'm paranoid about running out of beer I brew maybe twice a month but I just set up my 4 tap kegerator and am trying to fill all 6 of my kegs.

 

[hannibalmdq]

the main time to worry about ferment temps is during the first 5-7 days. after that it's still important to maintain a fairly constant temperature (aka not swings of 10F from morning til midday then back down again at night), but you can allow it to rise up to ambient 75F until cold crashing it,

I'm almost at the point where I'd say that ferment temps only need to be controlled until you hit about 70% of your target attenuation. This can be as early as 2 days for some brews, and almost always by day 3, assuming nominal gravities and a big slug of healthy yeast. Often I find I'm at or within a with a point or two of terminal gravity by 72 hours for the yeasts I use most often.

I don't get above 75F, but that's only because that's as hot as my basement ever gets. I'd venture a guess you could press that limit further.

After terminal gravity is reached the yeast really only stay active and clean things up for a few extra days. Warmer temps will mean longer floc times, but as you pointed out, you can crash them out before packaging.

I'd really like to do some comparisons on extended cold conditioning verse warm storage. Unfortunately, I'm not set up to do that.

 

[joshesmusica]

I'm almost at the point where I'd say that ferment temps only need to be controlled until you hit about 70% of your target attenuation. This can be as early as 2 days for some brews, and almost always by day 3, assuming nominal gravities and a big slug of healthy yeast. Often I find I'm at or within a with a point or two of terminal gravity by 72 hours for the yeasts I use most often.

I don't get above 75F, but that's only because that's as hot as my basement ever gets. I'd venture a guess you could press that limit further.

After terminal gravity is reached the yeast really only stay active and clean things up for a few extra days. Warmer temps will mean longer floc times, but as you pointed out, you can crash them out before packaging.

I'd really like to do some comparisons on extended cold conditioning verse warm storage. Unfortunately, I'm not set up to do that.

i'm starting to get the same feeling about that time frame, but i gave the normally recommended suggestions just because i can't prove it. i'm about to be set up to start testing different things, but only on a 4L scale.

 

[hannibalmdq]

i'm starting to get the same feeling about that time frame, but i gave the normally recommended suggestions just because i can't prove it. i'm about to be set up to start testing different things, but only on a 4L scale.

I'm glad I'm not alone on this. Playing around with the fermentation schedule has been very fun for me. I'm constantly amazed at what the yeast are capable of and I know I have so much more to learn.

One of the nice thing about smaller batches is the cost of failure isn't that high. I feel like small batch brewers are sometimes more adventurous because of the volumes they brew at. I normally end up with a little more than a case (2.75 gallons into the fermentor) and even at that scale I occasionally find myself sticking to tradition for no other reason than I don't want to jinx a batch.