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Old 07-24-2012, 03:31 PM   #1
cd38
 
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I have a stick on thermometer on the side of my ale pail. Is fermentation higher than that or is it when you use a probe in the air the ferm temp is hotter? Thanks for the help

 
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Old 07-24-2012, 03:40 PM   #2
cmybeer
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Nice, I literally just posted a question about the fermometers and their accuracy on another site because I've just never thought about it before. I'm assuming they measure the internal temp of the carboy/pail but I was wondering about their accuracy. I know fermentation can run 5* warmer than ambient temp due to heat created by the process.

 
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Old 07-24-2012, 03:41 PM   #3
william_shakes_beer
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I did a heat study a few batches back. First lesson I learned was that my primary thermometer was inaccurate by 11 degrees. Its now a paper weight. When I finally got the proper tools I found that my wort is usually about 2 degrees warmer than the sensor attached to the outside of the bucket.

 
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Old 07-24-2012, 03:54 PM   #4
cd38
 
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yea I have always heard the 5 degress above ambient, but I have it is a SoFC. My stick on thermometer says 72. So hopefully it is only 2 degrees. BTW using US-05 so shouldnt be a problem.

 
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Old 07-24-2012, 05:08 PM   #5
molson
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Your stick on thermometer is measuring the wort temp not the ambient air temperature. So if it says 72 then your wort is probably 72, now it might be a little warmer near the center of the wort. There was a pretty good article in byo this month about fermentation temperatures.

 
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Old 07-24-2012, 08:13 PM   #6
cd38
 
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sweet thanks man that is the answer I was looking for. Its hot as HELL here in Mexico

 
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Old 07-24-2012, 08:17 PM   #7
SpeedYellow
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The stick-on thermometer is measuring the glass temperature, which will fall somewhere between wort and air temp. The bigger question is whether or not it's even accurate. You should stick a lab thermometer inside the wort and calibrate it (so to speak) yourself.

The article in BYOB this month seemed questionable ... author said the wort temp in the middle will be higher than nearer the edges. That seems very suspicious, especially in an actively churning fermentation. No data supported that claim.
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Old 07-24-2012, 08:24 PM   #8
molson
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I have a thermopen and used that to measure the wort a few times and it was always spot on or .5 within what the stick on thermometer was reading. Based on that I believe they are pretty accurate.

 
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Old 07-24-2012, 08:32 PM   #9
molson
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Check out this thread http://www.homebrewtalk.com/f163/car...l-temp-174141/

 
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