Author Topic: Need to get something to lower temp during fermentation  (Read 1576 times)


Offline Stevie

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Re: Need to get something to lower temp during fermentation
« Reply #16 on: June 16, 2017, 02:13:11 PM »
Themowells are cool, but in my experience there is too much lag with a standard thermostat. By the time the probe is at target, the chamber and outside of the vessel is well below. This results in large negative temp swings.

Fancier controllers are able to compensate for this overshoot, but are more expensive or may require multiple components and wiring.

Offline rob_f

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Re: Need to get something to lower temp during fermentation
« Reply #17 on: June 20, 2017, 01:04:10 PM »
Well, the reverse is true with the probe on the side. The center of the fermenter is at a higher temperature during fermentation.  So you either get an unknown higher temp or an unknown lower temp where your probe isn't.
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Offline Joe Sr.

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Re: Need to get something to lower temp during fermentation
« Reply #18 on: June 20, 2017, 03:34:08 PM »
My goal is for a stable temp, as much as possible.  That temp is likely to be within a band of several degrees, but that's OK.  The actual temp to me (assuming it is within range of where it should be) is not as important as a stable and consistent temp.
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Offline a10t2

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Re: Need to get something to lower temp during fermentation
« Reply #19 on: June 20, 2017, 05:27:04 PM »
The center of the fermenter is at a higher temperature during fermentation.

Personally, I've never seen a measurable difference.
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Re: Need to get something to lower temp during fermentation
« Reply #20 on: June 20, 2017, 05:37:01 PM »
The center of the fermenter is at a higher temperature during fermentation.

Personally, I've never seen a measurable difference.

Neither have I.
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Offline rob_f

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Re: Need to get something to lower temp during fermentation
« Reply #21 on: June 20, 2017, 05:45:09 PM »
If fermentation is generating heat uniformly throughout and you are withdrawing heat from the surface, temperature in the center has to be higher. That's science.

Does it make a difference? I've never noticed.  I was just pointing out that neither the probe on the side or the one in the center gives you a uniform temperature throughout.
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Offline a10t2

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Re: Need to get something to lower temp during fermentation
« Reply #22 on: June 21, 2017, 06:41:25 PM »
If fermentation is generating heat uniformly throughout and you are withdrawing heat from the surface, temperature in the center has to be higher. That's science.

Does it make a difference? I've never noticed.  I was just pointing out that neither the probe on the side or the one in the center gives you a uniform temperature throughout.

That does make sense to me, but it's also science that the thermal conductivity of the beer is a couple orders of magnitude higher than the air around the fermenter.
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Offline charles1968

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Re: Need to get something to lower temp during fermentation
« Reply #23 on: June 21, 2017, 06:57:19 PM »
If fermentation is generating heat uniformly throughout and you are withdrawing heat from the surface, temperature in the center has to be higher. That's science.

Does it make a difference? I've never noticed.  I was just pointing out that neither the probe on the side or the one in the center gives you a uniform temperature throughout.

Remember it's a fluid so temperature differences would cause convection currents and remove the temp gradient. Plus there is already vigorous circulation during high krausen because so many CO2 bubbles are rising through the liquid.

Offline charles1968

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Re: Need to get something to lower temp during fermentation
« Reply #24 on: June 21, 2017, 07:00:15 PM »
In the absence of a good brew fridge and temp control, I still think a sleeping bag containing ice bottles beats a swamp cooler. Ambient temp in my house at the moment is 86F but my FV is at a stable and steady 65 with this method.