How To Temperature Control Your Fermenter For Under $100

How To Temperature Control Your Fermenter For Under $100

Building A Temperature Controlled Fermenter Kit For Under $100

So we decided that the Fermentasaurus is a great bit of brewing kit at a really good price. It has basically the same feature set as a stainless conical fermenter in that you can remove the trub without exposing your brew to air or having to rack it to another container.

It is also fantastic in that you can ferment under pressure and also use it as a keg!

The one thing it lacks when compared to say to say a Grainfather or SS Brewtech Conical is the ability to control the temperature during fermentation unless you put the whole thing in a fridge...

Well we decided to fix that!

A quick trip to Bunnings later and we were ready to hack our mini kegerator and make it an all in one brewing, chilling and serving pocket rocket!

What we bought was:

1 x 3m coil of copper pipe 1/2"

1 x 5m 13mm diameter vinyl tubing

3 x clamps to fit 11-16mm

1 x 240v 15 watt immersible water pump off ebay

1 x 240v heat belt for a fermenter again off ebay

1 x MK11 Temperature controller we had sitting around

1 x 1/2 size x 100mm deep gastronom plastic tray


Then we got to work....


The only thing to be really careful of is where you put the holes through your fridge, we were basically going in blind and just took an educated guess after examining where all the hose lead from the compressor and on the inside of the fridge. I think that it is a lot easier on bar fridges as a full size fridge has gas lines running all through the walls. If you go slow though and feel for any obstructions before cutting to hard or deep you should be fine.

We now have a complete brewery and kegerator that holds up to 30L of 4 different drinks in a footprint of 50cm x 50cm... Anyone can find that space in their apartment!


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I’ve watched the video " build a temperature control fermenter for under $100 " and I want to do this project. I’ve got a few questions to ask please.

1. What have you been able to get the Temperature in the fermenter down to using this cooling system?? —for me, I wanting to do Lagers and I would like to get the Temps down close to 40-43 F. degrees / 4 -6 degrees Celsius respectively (for Lager yeast)
2. What size of mini fridge are you using ?..,, I’ve looked at a couple in the 3.2 and 3.6 cu. ft. range…both have a full icebox size for mini fridges…will these work?

Thank you, in advance
David Clemons

David Clemons

Hello David, I like that name too :-)
My questions are several on your the cooling system you made for the fermentasaurus fermenter. 1. The video shows the temp controller readout is in Celsius correct ? 2. With this cooling system..working how cool have you managed to get the wort/beer in the fermenter down to? ( I want to be able to do Lagers. " I currently have a BrewJacket Immersion Pro….and although it works the best I’ve been able to get my temp down is only about 25 degrees—not the advertised 35 degrees from room ambient temperature and that is using the insulated jacket" My current system works but is very limited to certain lager yeast the can stand the 50’s F range which limits the styles of Lagers I can make…But as doing Ales no problem" 3. The last question is the size of your mini freeze you used—how many cu. ft. is it?? I’ve been looking at using a Tramontina 3.2 Cu.Ft. Compact Refrigerator or a Haier 4.5 cu. ft. Compact Refrigerator both from Sams Club they are only a few dollars apart.

Thank you,
David Clemons

David (Ace)

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