Temperature Controlled Plastic Bucket Fermenter

[rwr1992]

After being annoyed with my previous setup of my keezer/fermentation chamber not being able to serve beer colder than 65 degrees while fermenting a beer, I decided to do some research and venture out into a more standalone option than getting another fridge/chest freezer to convert to a fermentation chamber. I settled on converting the Ale Pail sitting in the garage, to a water cooled fermentation vessel. The idea is essentially the same as an immersion chiller, just sealed off on top and using ice water recirculated from a cooler coupled with a digital temperature controller. Keep in mind this is only a cooling setup as I live in Florida and keeping things warm enough is almost never a concern.

Supplies

• Ale Pail 6.5 Gallon Plastic Fermentation Bucket with Spigot (previously owned)
• 25' 3/8" OD Stainless Steel Immersion Chiller (purchased on eBay for $35)
• 1/4" Stainless Steel Thermowell (previously owned)
• Inkbird Digital Temperature Controller ($35)
• 80GPH Pond Pump ($9)
• 3/8"ID Rubber Grommet ($4)
• 1/4"ID Rubber Grommet ($2)
• 1/2" Vinyl Tubing ($3)\
• Cooler (previously owned)

Build Process

Build process is pretty straight forward. Drill a 3/8" hole in the center of the lid for the 1/4" grommet and insert thermowell. Mark the entry and exit points of your immersion chiller and drill 1/2" hole for 3/8" grommet and slide chiller into place. For both of these, make sure to vertically center them inside what would be your typical fermentation volume. For me, this meant centering at the 2-1/2" gallon mark. After all this, simply run the tubing from the pump to chiller and back to the cooler. Connect your pump to the digital temperature controller and set desired temp. Due to Newton's Law of Cooling that states that the rate of change of temperature of an object is proportional to the difference between its own temperature and the surrounding temperature, this setup will work best when the temperature difference between the cooler and fermentation vessel is high - so use ice or frozen bottles to keep the water in the cooler much colder than desired fermentation temperature.

Room for Improvement

• Insulate fermentation bucket and cooling lines
• Use a different cooler with holes drilled in it for cooling line runs
• Use keezer to keep circulating water cold to avoid the ice pack routine
• Upgrade bucket to conical

 

[shanecb]

Pretty neat! I've thought about this type of temperature control before. How stable is the temp with this?

 

[rwr1992]

Pretty neat! I've thought about this type of temperature control before. How stable is the temp with this?

I just brewed an IPA yesterday and used my standard immersion chiller to get the wort down to 100 and then cold crashed to 68 in another 15 minutes with this cooler. As far as temperature stability, I don’t have a method of recording data but my Inkbird is set to turn on at +1 degree and it does a great job of keeping it there. I would think it cycles maybe once per hour or two?

 

[Kerrbrewer]

I have good lager results with a similar setup using Chapman Univessels and a Cool Brewing bag.

http:// https://www.homebrewtalk.com/showthread.php?t=591322

 

[bigdawg86]

Interesting... I have a 25 foot stainless chiller I don't use and was seriously looking at the SSbrewtech brew bucket... but this may be an option for now. I have a bucket heater solution (https://www.homebrewtalk.com/showpost.php?p=8138398&postcount=7) but this would work for cooling.

I too have a keezer that becomes a ferm chamber so I have 3 corny kegs going, then when they kick I brew 3 times so I can make it a keezer again. It drives me nuts that buckets aren't air tight so airlock activity (even gamma lids don't seal well) is a bust except at peak fermentation, but this may work.