What fermentation temp control swings are acceptable?

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If a yeast says ideal temps are 18-25C for example:

An extreme scenario is the temps swinging daily/nightly between the ranges. Prob not good.

But if you had a pretty stable room temp and let's say your fermentation swings between 18-20C I can't imagine that's worth getting your knickers in a twist over.

Anyone else not bother with temp control because their temp swings are in an acceptable range?

Or conversely, is keeping the temp at X and not one degree different a hill you're willing to die on?
 
Before most brewers had upto date digital controllers a swing of 2 degrees would have been acceptable IMO.
Ps I do not have a brewing fridge so use yeast that suits my temp or cooler room if needed such as a garage which is at 16c at the moment so ok for Novolager yeast or I use Kveik in hotter weather and Beoir for ales. I do have a heated plate warmer which I wrap around and get some control with that
 
Before most brewers had upto date digital controllers a swing of 2 degrees would have been acceptable IMO.
Ps I do not have a brewing fridge so use yeast that suits my temp or cooler room if needed such as a garage which is at 16c at the moment so ok for Novolager yeast or I use Kveik in hotter weather and Beoir for ales. I do have a heated plate warmer which I wrap around and get some control with that
Ya I choose my yeast based on the season. Kveik is a game changer for the hot summers and saves the hardest part of chilling.

Kölsch yeast is great in winter.

The other ale yeasts I find very forgiving if your room temp is somewhat consistent. The few degrees drop in the night is too short and gradual to affect things I think/hope.

Might get a Rapt Pill to confirm whether or not I need to worry about it
 
I use a Ispindel to monitor my temp so as to stay pretty stable and can add heat with the plate warmer that I use
 
Ya I choose my yeast based on the season. Kveik is a game changer for the hot summers and saves the hardest part of chilling.
I didn't have any joy, with kveik yeast last year. But have found good temp control improves quality. That said room temp does work.
 
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Until very recently, I didn't worry about temperature control. I ferment in my utility room which stays roughly 17-21 degrees throughout winter due to the central heating. This had a negligible impact on the beer temperature which fluctuated by maybe a degree. In summer, it was largely the same story (no central heating, but the house stayed relatively constant, maybe a bit higher in hot periods). I don't brew lagers, so thankfully the yeast fermentation temperature is in line with room temperature.

Recently I have just bought an insulating jacket and a heat belt. This is for when I want to ferment warm (24° etc). This is partly because my big Belgian beers need the extra heat to get the flavours I wanted, but partly because it's a new toy to play with).

In short, for me, I don't fret temperature fluctuations at all.
 
Until very recently, I didn't worry about temperature control. I ferment in my utility room which stays roughly 17-21 degrees throughout winter due to the central heating. This had a negligible impact on the beer temperature which fluctuated by maybe a degree. In summer, it was largely the same story (no central heating, but the house stayed relatively constant, maybe a bit higher in hot periods). I don't brew lagers, so thankfully the yeast fermentation temperature is in line with room temperature.

Recently I have just bought an insulating jacket and a heat belt. This is for when I want to ferment warm (24° etc). This is partly because my big Belgian beers need the extra heat to get the flavours I wanted, but partly because it's a new toy to play with).

In short, for me, I don't fret temperature fluctuations at all.
I'm hoping the fermentation heat and ambient temp will prevent a temp drop in my kveik during summer. I'll keep those on the balcony to enjoy the heat
 
If a yeast says ideal temps are 18-25C for example:

An extreme scenario is the temps swinging daily/nightly between the ranges. Prob not good.

But if you had a pretty stable room temp and let's say your fermentation swings between 18-20C I can't imagine that's worth getting your knickers in a twist over.

Anyone else not bother with temp control because their temp swings are in an acceptable range?

Or conversely, is keeping the temp at X and not one degree different a hill you're willing to die on?
First of all ambient temperature is different to fermenting temperature, while fermenting yeast produces exothermic temperature much like a compost heat. It is possible for the exothermic temperature to be 7 to 8 degrees higher than ambient but usually about 3 degrees higher than ambient.
You will know when you have your first beer that fermentation was to high, also by how quick fermentation finished.
Esters produced by fermenting at a temperature beyond recommended are way over the top, fortunately theses esters do subside but do not produce an award winning beer.
 
I like that foxy.

The point is, should we be thinking to optimise our temp control, not just.. what it within tolerable limits 🤣🤣

Fermentation temps imo are just as important as mash temps.

Boiling or not (just a few degrees different) does give a very different brew.

Like it or not, beer is a right temp at the right time game. Even when it's in the glass.
 
Both. I have a brew fridge that controls temperature and an open fermenter that I use without any temperature control. Both ferment fine. In the open fv I find, if the yeast is health and pitched at the correct rate, I'll get a short 6-8 lag time and then 2-3 days of exponential growth, aka fermentation. During that time yeast will create heat, which then radiates off creates a gradual, gentle rise in wort temperature of 2-3°c, even if ambient fluctuates.

Cooling is only required where you'd want to suppress esters, suppressing growth*. So, lager or anything hoppy american goes in the fridge. Anything British and Belgian goes in the open FV.

Obviously, if your ambient temperature is in the mid to high 20's your going to need to bring that down. But, IMHO happy yeast make good beer, gentle changes in conditions are fine, forced extremes less so. Especially if there's other issues like low viability, low pitch rate, low wort nutrient etc. Let healthy yeast do its thing.

*Pressure is an alternative.
 
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The point is, should we be thinking to optimise our temp control, not just.. what it within tolerable limits
It all depends on what is important to you. I don't think anyone is doubting that optimum fermentation temperature will give you the optimum beer. But it is more work/hassle. And if temperature control doesn't make a noticeable difference over ambient temperature fermentation (or makes it 0.5% better) then it's up to each individual to decide what's more important - the ease of simplicity, or the ever-so-sightly better beer.

I never strive to make the perfect beer by obsessing over every detail because it takes the fun out of the hobby.
 
I'm not sure I would call ensuring optimum fermentation temperature more hassle, apart from the initial hassle of setting up I find it no hassle at all.

Depends on how you're set for space I think would most likely be the biggest hurdle

I never strive to make the perfect beer by obsessing over every detail because it takes the fun out of the hobby.

I'm the same but I know for some brewers chasing perfection is part of the fun!
 
Depends on how you're set for space I think would most likely be the biggest hurdle



I'm the same but I know for some brewers chasing perfection is part of the fun!
It isn’t chasing perfection, there are those who will put effort into what they are trying to achieve and those that don’t. The ones that just go with near enough is good enough will always be an underachiever in life, as well as what hobby they pursue. Best way to approach anything, hobby, work, sport always give it your best shot.
 
It isn’t chasing perfection, there are those who will put effort into what they are trying to achieve and those that don’t. The ones that just go with near enough is good enough will always be an underachiever in life, as well as what hobby they pursue. Best way to approach anything, hobby, work, sport always give it your best shot.
Calm down lad. It isn't a binary choice between full effort and no effort.

The fact that you drink beer means you're not giving your chosen sport your best shot.

By your logic, you are an underachiever in life.

And I refuse to be talked down to by one of life's underachievers.
 
I have been wondering about this also as I will be starting a Stout kit very soon and I think I should be able to hold a steady 18 degrees, but that is right on the edge of the limits. I have no temp control, but if I wrap the fermenter, then it should support to maintain the residual heat the yeast will create, so hopefully I get 20 degrees. I did consider a cheap heat mat, but it runs a constant temp and I am more concerned with over heating than it sitting at the cooler end of the scales. I won't be there to check on it regularly so I can't trust a heat mat without temp control and right now, I am not in a position to invest in a digital controlled mat.

I brewed my last batch at 17 degrees with Novalager and that went well. If I am running at the low end of the temp range with a standard stout/ale yeast, will I have issues?
 

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