Can yeast over heat itself

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Hopperty

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this is my first brew using a beerkit-enhancer, and it seems to have taken off pretty rapidly and is generating a lot of its own heat. Could it warm itself to a point where the yeast kills itself - or would it be self limiting ?


Just to set the scene; I brew in the garage and it is fairly cold in there (1.5°c at the moment) The FV sits inside a heavily insulated box that has up until now worked wonderfully. But this brew (started 7 hrs ago) is cooking itself, temp was up to 23.5 and still climbing. I can remove the insulating box but then the heater will probably gave to work hard to keep it between 19.5 & 20.5. But if I leave the box on could it climb to a temp that damages the yeast ?
 
It sounds like it will keep climbing so you may develop some unwanted flavours unless you cool it.
As it is cool in there anyway I would remove the box and maybe use a thin towel or a basic cardboard box overnight. When things settle down in a few days go back and try the insulated box.

Ultimately you will need to figure out some form of temperature control to save you from this kind of worry.
Just fitting a fan on the top of your insulated box with a thermostat would probably work, and you could sit it on a heat mat for heating if it gets too cool.

I'm using an STC1000 mounted in a piece of rectangular ducting - https://www.ebay.co.uk/itm/Digital-...hash=item36540deba3:m:mSJsSsBoZl_0-_COhZDrz2w
 
It is temp controlled for heat, and up until now I have never had this problem of it generating too much of its own heat, may be I will have to consider a temp controlled cooling fan.

As for this brew, I have removed the box and just draped a coat over the top for tonight and it is starting to cool, back down to 21, the heater will come back on at 19.5

It would be interesting to see what temp it would have risen too if left inside the insulated box, but I don't want to risk a whole 40 pint brew.
 
In the 40 range (Centigrade) is when yeast starts to die off. The exothermic temperature in the centre of a fermenting vessel can be as much as 8 degrees higher than ambient temperature, yeast dependent.
You really should be controlling the temperature more accurately to get consistency in your brews.
 
I make wine i have yet to make the jump to beers.
But in over 40yrs winemaking i can say the secret is temp control.
Wild swings up or down are to be avoided like the plague
 
I brew in the airing cupboard apart from in summer when the house generally is warm enough to brew in. I control the temperature just by adjusting how much I leave the door open - works surprisingly well, with a temperature probe lashed to the side of the FV so I can keep an eye on things.
 
I use a heating pad under the FV but operated by a plug in wall timer, The type that has 4 switching points each hour.
That way I can control the temp almost spot on - less time at the start of fermentation when it's producing it's own heat,
a bit more at night when the central heating is off, etc. with a bit of tweaking and preempting I have managed to keep my
brew at 22C the whole fermentation period. Also I wrap an old beach towel around the bucket so it holds it's temp during
the off periods.

Paul
 
It sounds like it will keep climbing so you may develop some unwanted flavours unless you cool it.
As it is cool in there anyway I would remove the box and maybe use a thin towel or a basic cardboard box overnight. When things settle down in a few days go back and try the insulated box.

Ultimately you will need to figure out some form of temperature control to save you from this kind of worry.
Just fitting a fan on the top of your insulated box with a thermostat would probably work, and you could sit it on a heat mat for heating if it gets too cool.

I'm using an STC1000 mounted in a piece of rectangular ducting - https://www.ebay.co.uk/itm/Digital-...hash=item36540deba3:m:mSJsSsBoZl_0-_COhZDrz2w

This is a great idea for controlling for the cool side in winter. My dad wants to move his brew to the shed, he has a heat belt and I was thinking of getting a temp controller for him, but never thought of using a fan to control for the cool side. Cheers
 
@Hopperty
I use a water bath which I keep in my garage. It is heated by a 50 watt heater. The garage never drops below 5*C but the heater can still control and maintain a steady bath temperature up to say 20*C under these conditions. I cover my water bath/FV with old towels to act as insulation and when necessary can remove them exposing the top of the FV if needed to release any heat. And in warmer weather I can add ice or chilled water to the bath or a wet towel over (evaporative cooling) to lower the temperature.
So my suggestion to you is to consider using the water bath perhaps using a 75w heater given your low ambient temperatures, on the basis that it gives you more flexibility than your box.
More here
https://www.thehomebrewforum.co.uk/threads/how-to-set-up-a-water-bath-for-your-fv.66407/
But the next step up of course is a brew fridge.
And in my view using brew enhancer is unlikely to make all that much difference to the fermentation rate.
 
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