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What do you use to insulate your fermentation chamber temp probe?

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I just use some bubble wrap and tape. I know it's reading the temp of the fermenter because sometimes the air temp gets well below the fermenter temp.

This is what I have been doing ever since I got my fridge and was happy with it when using my plastic buckets (this is my first batch with a glass carboy). My only concern with taping it to the side is the probe may read the glass temp which may be different from the beer when the fridge is on.

Could the glass cool down quicker than the beer? I know the beer will take some time to cool down even a degree because of the large mass. Will the glass carboy read a lower temp because it is touching the cold air and isn't as large of a mass?
 
This is what I have been doing ever since I got my fridge and was happy with it when using my plastic buckets (this is my first batch with a glass carboy). My only concern with taping it to the side is the probe may read the glass temp which may be different from the beer when the fridge is on.

Could the glass cool down quicker than the beer? I know the beer will take some time to cool down even a degree because of the large mass. Will the glass carboy read a lower temp because it is touching the cold air and isn't as large of a mass?

But the glass is also touching the warmer beer. Honestly, once my wort gets down to the set temp, and everything stabilizes, my freezer only kicks on maybe once every hour or two during active fermentation. Then after fermentation is done, a few times a day. Once temps are stable they hold within a degree or two.
 
I have drilled my bucket lids with a stepped bit to accept the MoreBeer Thermowell that is mounted to a stopper. I fill the thermowell with StarSan to ensure i am getting the temp of the liquid and not any air inside the termowell.

That being said I've put the probe on a second controller with the probe on the side of the bucket covered with cardboard and it's virtually the same reading.

I believe that you will make great beer with either method.
 
This is what I have been doing ever since I got my fridge and was happy with it when using my plastic buckets (this is my first batch with a glass carboy). My only concern with taping it to the side is the probe may read the glass temp which may be different from the beer when the fridge is on.

Could the glass cool down quicker than the beer? I know the beer will take some time to cool down even a degree because of the large mass. Will the glass carboy read a lower temp because it is touching the cold air and isn't as large of a mass?


If left alone, the temperature of the beer and container will tend toward the control temperature over the course of a few hours. Once there, only some kind of temperature disturbance will upset the balance. For example, opening the fridge/freezer and letting in hot summer air while you monkey around with a wine thief might temporarily elevate the probe reading and trigger the compressor to kick on. But as soon as the fridge is closed again, the temperature read by the probe will quite quickly settle back to a reading more indicative of the beer temperature. The few minutes that the compressor ends up running to get there (if at all) will have very minimal impact on the temperature of 5-10 gallons of beer.

IMO, the main reason for insulating the probe is to prevent unnecessary cycling of the compressor on your fridge when you open the door. Very basic probe insulation and compressor delay setting of 10 minutes on the STC is enough to keep that problem at bay.
 
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