Conical temperature measurement position

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fuzzybee

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I have 6 gallons of Munich Dunkel moving along in my conical. Currently, it's sitting on my back porch, because it's cold outside, and I'm worried the garage would be too warm for this yeast. I have an iSpindel floating in it, and also have a thermowell about 2" above the cone, where I have my InkBird thermostat probe. I have this connected to a heating mat wrapped around the conical. I've noticed a pretty large variant in the temperature in the vessel - for instance, right now the thermostat is reading 42.5, while the iSpindel is showing 48. Should I set the thermostat to a lower temperature (around 45) to try to attain ~50F at the iSpindel, should I set the thermostat for 50 and let the top of the wort be warmer, or should I shoot for somewhere in the middle?
 
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VikeMan

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I've never known the temperature in a conical (or any fermenter) to stratify like that when the heat source is at/toward the bottom. My guess is that either your Inkbird or your iSpindel needs to be calibrated.

Another possibility would be a thermowell with a diameter that's too large, allowing too much exchange between the ambient air and the inside of the thermowell, causing the the readings to be influenced too much by ambient temp rather than beer fermenter temp.
 

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Try plugging the opening around the thermostat cable to reduce the amount of outside air influencing it's reading. I use small rubber (silicone) stoppers for that (bought for another use, but there are some small enough to do the job). At most, I see a 1F difference between the sensor and the Tilt inside my conical.
 
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I tape my temp probe (under a patch of insulation) near top of tapered part of conical, this seems to give a decent average temp. Since my Fermwrap heat pad can only practically be attached to cylindrical part of fermentor, which is upper 2/3 of it.

If you only have one heat sensor, perhaps try it in a few different places for an hour or so to get a idea of best position for your conical.
 
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fuzzybee

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I've never known the temperature in a conical (or any fermenter) to stratify like that when the heat source is at/toward the bottom. My guess is that either your Inkbird or your iSpindel needs to be calibrated.

Another possibility would be a thermowell with a diameter that's too large, allowing too much exchange between the ambient air and the inside of the thermowell, causing the the readings to be influenced too much by ambient temp rather than beer fermenter temp.

My heating source is wrapped around the back of the conical, and reaches almost from the top to the bottom of the vessel above the cone.

I'll try to get some sort of insulation around the thermowell entrance. Thanks!
 

Golddiggie

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All the heating elements I've seen for conicals go around the cone (or partially around them). Since heat rises, it makes more sense to heat from the lowest point on the fermenter than the middle.
 
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fuzzybee

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All the heating elements I've seen for conicals go around the cone (or partially around them). Since heat rises, it makes more sense to heat from the lowest point on the fermenter than the middle.
I'll try to see about dropping this one some. Thanks!
 

hotbeer

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Perhaps there is too much conduction of heat from what it's sitting on. Get a piece of rigid styrofoam or something well insulated to sit it on. Maybe just set it down in a cooler if you have one that size.

Lid open or closed that's your choice. As long as there isn't a spike in temp to take the inside of the cooler over the desired temperature, then lid closed will be more stable temps.
 

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Get a piece of rigid styrofoam or something well insulated to sit it on. Maybe just set it down in a cooler if you have one that size.

Lid open or closed that's your choice. As long as there isn't a spike in temp to take the inside of the cooler over the desired temperature, then lid closed will be more stable temps.
Hard to do with conical fermenters. I've not seen a cooler large enough to put one in. If you put the cooler on it's side, I don't see it being stable enough to trust. What you posted might work for a bucket fermenter, but not conical.
 

hotbeer

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Hard to do with conical fermenters.
Yeah...

By the time I read down this far, I forgot it was a conical.

Though sheets of foam insulation aren't too costly at the big box home stores. I've used them to build big boxes to provide insulation from rapid ambient temp swings. Only a sharp knife or box cutter, a straight edge and a roll of shipping tape required for assembly. Or gorilla cement if for outdoors.

Not sure if that will help the stratification in the fermenter if it's not heat being lost from direct conduction. Though a constant and slight cold breeze moving over the entire fermenter will probably cool the smaller part of the fermenter more than the upper part.

Poorly worded I know, so lets not get into the technical part about heat transfer.
 

eric19312

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For the current beer I'd confirm the inkbird calibration and then plug up the thermowell hole as suggested above. I've used a bit of masking tape wrapped around the probe wire in the past, think you could also inject a bit of vaseline if you had a syringe handy.

Possibly there is some warmer beer up at the top where the Spindle is floating. Depending on size of the fermentor you could give the thing a swirl or rock it a bit to mix and see if the spindle changes. Either way once the inkbird is calibrated I'd rely on that measurement for temperature corrections for now.
 

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I'm waiting for Brewers Hardware to have their jacketed conical (15 gallon) in stock again so that I can give one a try. I'm hoping that with the insulation, and double wall, any heat the yeast produces will stay inside unless offset with the glycol chiller. Which will make the heating elements not needed. Besides, not really sure how you would heat the insides with that setup. Unless you warmed up the glycol solution at least (not something I would want to do at this time).
 
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fuzzybee

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So I did a bad thing and changed three variables at the same time :D

I taped up the thermowell entrance, lowered the heating pad, and also moved it into the garage. Now I have about a degree difference between my Inkbird sensor and the iSpindel. Much better.
 

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