Fermentation Temperature Control

[dilligara]

I'm thinking of using a wine cooler as a means of maintaining a constant fermentation temperature. The one I'm looking at has a temperature range of 41 - 65 degrees. The only problem is that it's not tall enough for a carboy with a standard airlock. My thought is to use a stopper with a hole and run tubing down to a container of water at the bottom of the wine cooler. Would appreciate feedback on this idea, or input from anyone who's tried using a wine cooler in this way.

Thanks in advance,
Sam

 

[mac_1103]

My thought is to use a stopper with a hole and run tubing down to a container of water at the bottom of the wine cooler.

Fill the container with Starsan instead of water.

 

[palmtrees]

Yeah, you can do your airlock that way with starsan. Get an inkbird temp controller to hook up to the wine fridge, and you'll be good to go.

 

[dilligara]

Thanks very much.

 

[hotbeer]

The 41 - 65°F might be on the cooler side of some ferment temps for Ales. Great for lagers though.

While it won't be outside the range of most Ale yeast, you might get some different flavor notes from some of the yeasts than you would with 69°F or higher temps.

Neither necessarily being bad, just different.

 

[day_trippr]

If the wine cooler uses a conventional mechanical bulb & capillary style thermostat they can often be adjusted to move their effective temperature range up. This thread describes the process using a freezer but fridges often use the exact same type of thermostat...

https://www.homebrewtalk.com/thread...tat-to-32f-eliminate-external-control.249612/
Cheers!

 

[RM-MN]

The only problem is that it's not tall enough for a carboy with a standard airlock.

Stretch a piece of plastic over the opening and hold it in place with a rubber band. It will do the same thing as an airlock except you won't be able to see the bubbles.

 

[Jag75]

Stretch a piece of plastic over the opening and hold it in place with a rubber band. It will do the same thing as an airlock except you won't be able to see the bubbles.

Bubble watching is our main reason for brewing

 

[dilligara]

Very helpful suggestions. Thanks very much

 

[bc-roush]

I have a wine cooler I got for free from offerup. It has thermoelectric cooling which doesn’t use a compressor. The cool thing with this type of system is it uses a solid state die that you apply 12v to one direction and it’ll cool if you reverse the polarity it’ll heat. I simply put a switch in that swaps polarity depending on my goal. It’s then hooked to the wall with an inkbird. I’ve fermented a seltzer at 87 and it worked flawlessly. People love giving away wine fridges. Keep an eye out. My main kegerator is a converted wine fridge as well with mods to drop temp into beer range.

 

[wsmith1625]

If you can't turn the internal thermostat down then just bypass it so Inkbird is controlling when it turns on and off. Set the delay on the Inkbird to 3 minutes.

 

[Deadalus]

If you can't turn the internal thermostat down then just bypass it so Inkbird is controlling when it turns on and off. Set the delay on the Inkbird to 3 minutes.

I bypassed mine this way. Mine is also a tad short for an airlock in a 6.5 gallon carboy so I use a SS blowoff tube down to a container with Starsan. I did take the light out too. Has bubbles!

 

[Deadalus]

Hacking the wine chiller was a little more complicated than the minifridge I have but it's doable. The electric diagram is probably on the back. My wine chiller had a digital temperature display, light, and then some buttons for red and white wine temps. That last feature was a problem because it kept resetting. It didn't have a memory feature I think was the issue and it was on a GFCI circuit. Anyway, I ended up rewiring it to be powered on at all times but controlled by the Inkbird.

 

[bc-roush]

You can trick a digital controller that uses a thermistor for temp sensing by adding a resistor in parallel. I used a 47k ohm resistor and my set temp is 20 higher than my desired. Basically set it at 57-58 and get 37-38 internal temp.

 

[BrianB]

How consistent is the temperature throughout the carboy during fermentation. Is the temperature reading on the stick on exterior thermometer going to be close to the temp at the center of the carboy or are there wild swings throughout the carboy. Was thinking of getting Anvil's Carboy Cooling System, but that sits in the center of the carboy, so the edges may be warmer. Any thoughts on whether the temp differences are an issue?

 

[day_trippr]

I can't speak specifically to the potential differential between a stick-on LCD strip reading vs a thermowell-mounted sensor. But I can relate extensive experiments using a ds18b20 sensor pinned to the side of a 6.5g glass carboy with a ~4"x4" pad of inch thick closed cell foam insulation over it, versus another ds18b20 in a thermowell positioned vertically and horizontally centered in the beer volume.

I never saw more than 0.5°F differential between the two probes (which were matched).
So I don't bother with thermowells and their sanitation needs, etc...

Cheers!

 

[BrianB]

Day_Tripper - thanks much for the reply. I was very curious about whether fuild in a 6 gallon carboy distributes heat and cooling evenly or not. From your experiments, sounds like there's really nothing to worry about in terms of an uneven temperature range within the carboy. One less thing to worry about. I appreciate your reply. All the best.

 

[day_trippr]

My pleasure. I wish I still had all the temperature plots but they were in an unprotected folder that got dumb-thumbed by yours truly into oblivion a year ago They were impressively informative, there was no denying that at least for 5-6 gallon class vessels there's not enough value added via thermowell vs a decently coupled and isolated sensor strapped to the side to justify the infection risk of the former.

I still have the probe sets and thermowell and patch panels to repeat the tests. Might do it some winter...

Cheers!

 

[mac_1103]

From your experiments, sounds like there's really nothing to worry about in terms of an uneven temperature range within the carboy. One less thing to worry about. I appreciate your reply.

Well, it's not like there's a whole lot you could do about it if the temperature did differ dramatically within the carboy. And it's very well established that worrying is just about the worst thing you can do for homebrew.

 

[BrianB]

mac_1103 - Thanks. I was just wondering about the temperature differential within the carboy. I was concerned that you might get a reading on the exterior or from a sensor in a thermowell in the center of the carboy that would be within range, but that other areas of the carboy would be out of optimal fermenting temp. If the latter was the case I was going to ask about whether a periodic light swirl of the carboy during the first few days of the heavy fermentation would solve that. I was considering a course in fluid temperature dynamics - just kidding. Thanks for the advice on not worrying.

In process: Mango Vanilla Hazy IPA

 

[Conehead]

I just looked around and found a free fridge.

 

[Arbe0]

If you can't turn the internal thermostat down then just bypass it so Inkbird is controlling when it turns on and off. Set the delay on the Inkbird to 3 minutes.

Make sure whatever controller you get, that it has heat and cooling on it