I’ve been asked many times in the past how to control the temperature of your fermenter when the tap water exceeds the desired fermentation temperature. I’ve seen lot’s of expensive equipment implemented, and I thought that there has to be a better way. The most common is fermentation fridges or fermentation chambers, and brewers would either lug a carboy into a deep freezer set to a thermostat, or buy a fermenter small enough to fit into a refrigerator. Both of these methods work, but let’s be honest, they’re a pain in the ass. What if you want to ferment a lager, and a porter at the same time? That means that you’ll need 2 refrigerators, right? Not necessarily.
I struggled with this problem myself, using tap water to ferment my brew and I’ve been using tap water controlled by a solenoid to regulate the fermentation temperatures in my conical fermenters. While it works fine, I wanted to get away from wasting so much water.
The solution I came up with started with a compressor driven aquarium water chiller. Water chillers chill water, but need to have the liquid pushed through them, so I use an aquarium magnetic drive pump for that. It can chill up to 3 fermenters at different temperatures at the same time, using just this single pump and a small aquarium chiller and a custom made pair of manifolds to add, or remove fermenters as you wish. This setup has room for expansion, and in fact it would be a perfect solution to chill multiple fermenters in a micro or nano brewery, sized appropriately. If you want to chill a single fermenter, or multiple fermenters, this tutorial should give you a good starting point. Now your cooling requirements will differ based on these factors; the ambient room temperature, the GPM flow of the water pump through the chiller, the size of fermenter and the number of fermenters you are planning on adding to the closed loop.
If you are running a bigger set up than what I’m using for this tutorial, you’ll need to properly size up your cooling needs so that you purchase a properly sized fermenter.
Learn how to actually build this setup at brausupply.com