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Question about temp on outside of carboy

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NCGirl

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New brewer here! Have my first batch of Hefeweizen fermenting in my closet (sucks not having a basement sometimes, lol). I lucked out and my dad and brother were here on brew night... both had brewed before so any questions got quickly answered. My DH is a general contractor (would that be HWMBO? No freakin' way, lol!!) and had copper tubing already so he made me a wort chiller AND set up the propane turkey fryer outside on the deck... so I ended up being able to do a full boil.

All in all it went well! Forgot to do a OG reading before I put the airlock on the carboy, but it was happily bubbling away when I checked on it 8 hours later.

My question is, I got one of those fishtank-like thermometer strips from my LHBS that attach to the outside of the carboy. How accurate is that? I chilled the wort down to 75F before putting straining it into the carboy and adding the yeast. When I checked the temp the next morning it was at 78. My house was at 70 but I think the active fermenting was keeping the temps up. I ended up moving the carboy out to the screen porch with a towel around it for a few hours - it was about 50 outside. Got the temp down to 70 where it's stayed. Bubbling activity slowed for a while but it's churning away now. Should I have chilled the wort down lower than 75F?
 
I wouldn't worry...

Ideally, chilling it down a bit more a would've been better, but it shouldn't affect it too much... I mean, if you had pitched at 85 degrees, that'd be bad.

As for the peal-and-stick thermometers, they're pretty good for what they are. Since I don't have a better way to measure the temperature, I assume they're correct (otherwise I'd go nuts).

Stabil fermentation temps are also important for the fermentation. As long as the fermentation temperature stabilized (and didn't fluctuate too much) at 70, then you're good to go. Consider putting the fermenter in a tub of water with a towel to wick water away with a fan on it. Or, simply add a bit of ice over the course of the day. Bottom line, stable temps at the desired temp is ideal... Will it still be yummy? You Betcha!!! Might be a bit more spicy than bananary...
 
Peel n' sticks are not very accurate, but they'll do in a pinch. Glad this was a hefe, as the temps are too warm for most other beers.

Since you have a contractor on hand, get dear hubby to help build you a fermenation chamber of some description with temperature control. Then attach a good thermometer to that and you'll have more accurate reading.

Your guess that the active fermentation drove temps up is correct -
we all do it differently; I typically pitch at about 65F and try to keep it between 62 and 65 for most all my ales.
 
In my experience those stickie therms are quite accurate. When compared to a thermowell they will only vary by a degree. They have been proven to work very well. Remember they are telling you the temp of the liquid inside, not the ambient temps. I too am fermenting a hefe right now and like to get the ferment temps at around 70.
 
I did a hefe a couple months ago and I was at the other extreme. I ended up at 62 degrees for a few days. Amazing how much a few degrees changes a beer. Mine had a strong banana smell and flavor, almost no spice. Let us know how it turns out...

For what it's worth, I'd recommend the fermentation chamber too... Either a freezer/fridge with a controller --or-- if HWMBO will agree, a room with a separate temperature control... AWESOME!!!
 
OK cool, I'm not going to worry about it now. I'll just remember for next time. And a fermentation chamber sounds like a great project for DH (sorry... HWMBO just doesn't roll off the tongue nicely, lol).
 
In my experience those stickie therms are quite accurate. When compared to a thermowell they will only vary by a degree. They have been proven to work very well. Remember they are telling you the temp of the liquid inside, not the ambient temps. I too am fermenting a hefe right now and like to get the ferment temps at around 70.

If anyone can corroborate or substantiate this it'll save me some money because I'm been considering installing thermowells on my buckets.
 
hmmm, I haven;t worried about it...

I can run an experiment and compare the stick-on temp with a floating thermometer. I'll have to do it this upcoming weekend unless someone has already done it.
 
If anyone can corroborate or substantiate this it'll save me some money because I'm been considering installing thermowells on my buckets.

I don't know what level of proof you'd need, but I have five fermenters, all of which have the stick-on thermometers. They all agree with each other, and every time I've checked them against a thermometer in the beer, they've agreed with it as well. At least within the resolution of the strip, they have (±1°F).

Which makes sense, if you think about it. Water (beer), plastic, and glass are much better conductors than air. http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html
 
I don't know what level of proof you'd need, but I have five fermenters, all of which have the stick-on thermometers. They all agree with each other, and every time I've checked them against a thermometer in the beer, they've agreed with it as well. At least within the resolution of the strip, they have (±1°F).

Agreed. I especially like the homebrew ones that show down to lager temps.
 
I don't know what level of proof you'd need, but I have five fermenters, all of which have the stick-on thermometers. They all agree with each other, and every time I've checked them against a thermometer in the beer, they've agreed with it as well. At least within the resolution of the strip, they have (±1°F).

Which makes sense, if you think about it. Water (beer), plastic, and glass are much better conductors than air. http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html

Cool to know... Thanks!
 
OK cool, I'm not going to worry about it now. I'll just remember for next time. And a fermentation chamber sounds like a great project for DH (sorry... HWMBO just doesn't roll off the tongue nicely, lol).

Psssst- it's HWMO. It's good.

If anyone can corroborate or substantiate this it'll save me some money because I'm been considering installing thermowells on my buckets.

As was mentioned, they tend to be within a degree or so of the temperature when taken with a thermowell or even my thermapen!
 
Let's see: He Who Must Obey.

Nope, didn't forget a B at all! :D

Hmmm... yes, there's still a Be and an ...ed on obey still missing...

The avatar is my grandson showing his opinion of the rabbit ears his mother put on him for the photos. You can just read his thoughts, huh?

No doubt... The wife and I have 5 that OFTEN give us a look like that when we try to get photos done....

Sorry, this went WAY :off:
 
If anyone can corroborate or substantiate this it'll save me some money because I'm been considering installing thermowells on my buckets.

I use the Fermometer brand ones, and they did extensive testing with them, including taking a full carboy at 65 degrees and putting it outside (with a digital thermometer in the wort.) In 20 degree weather. They say that for every 10 degree difference between the ambient and the liquid inside, the thermometer will be off by 1 degree. I have found them to be quite accurate.
 
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