So I’ve got this conical fermenter and I want to put some wort in it right away. Then it hits me… the garage is 47 degrees. So I need to figure out how to heat this thing. I need to get a temperature controller hooked up, a heating method and I need to make sure it works. Even though I bought a conical fermenter, I’m still cheap at heart and I don’t want to waste a batch that will not ferment because it is too cold.
So the first step is getting the temperature controller figured out. In my current setup I am using a borrowed Ranco controller on a wine fridge to temp control a 6-gallon Better Bottle. The Ranco temperature probe fits snugly in the Chronical thermowell. For now, that is what I will be using. However, I also have all the parts to build my own temperature controller with an STC-1000. When I make the transition to that controller, I will be able to use both the controller and the LCD thermometer that is included with the Chronical. With the Ranco, the only thing that fits in the thermowell is the temperature probe. So I will have to check the controller to know what the temperature is in the fermenter.
My heating method in the wine fridge was two 20-watt Flexwatts sheets hanging on the wall. This was not overly efficient because it was just heating the air in the fridge, but it made it easier for me to get the Better Bottles in and out of the fridge. For the conical, I took the Flexwatt sheets and cut them apart. I figured I would only need one wrapped around the cone of the conical. I was wrong. One sheet only provided an internal temperature 10 degrees F higher than ambient (with 12-gallons of water in the conical).
My garage has been sitting around 48 degrees F on our cooler days so I figured if I could get two sheets wired together I would have enough heat for a standard ale fermentation. My first attempt at wiring them together did not work. I thought I had clamped them together well enough, but one of the sheets was not getting power. So I completely tore it apart and redid the wiring.
These Flexwatt sheets get power using a clamp style connector. The clamp punctures the plastic coating on the sheet to reach a metal strip that runs on each side of the sheet. So when I rewired the sheets I took it completely apart and made sure the sheets were lined up and used a pair of pliers to make sure the clamp fully punctured. When I tested it with 12-gallons of water in the conical, I was able to hold an internal temperature 18 degrees F over ambient. I did some testing of water at the top, middle and bottom of the conical and the temperature was consistent throughout the vessel. Although heat rises, I was worried having the heat all at the bottom would cause the base of the conical to be very hot and gradually get cooler. I’m glad that is not a concern.
SS Brewtech now sells a heating/cooling kit that is designed for their Chronical line. They have a heating pad that wraps around the cone in a similar method that I used. Their heating pad is 60-watts. My two sheets are a combined 40-watts and are capable of barely holding the temperatures I need in my standard low temperature scenario. Depending on how the first couple beers go, I may have to get an additional sheet to wire in parallel with my current two to give myself some extra cushion.
Another option for additional heat would be to pump hot water through the coil to get the temperature higher. This could be beneficial for cold winters or beer styles that have a higher fermentation temperature like Belgians. A heat stick could be used to maintain the temperature of the water. Currently, I do not have a pump to use for this setup. SS Brewtech recommends a pump with a flow rate of 8-10 L/min and a head of roughly 4-6 meters. This is essentially what they sell in their kit and individually. However, their pump uses a connector that is specific to their FTS temperature control system. It is not a standard plug that could be used on any system.
Heating is the only temperature control I need in the winter. However, by the time spring arrives I will need to have my cooling setup figured out. In the spring and fall I will definitely need heating and cooling. When I have the cooling setup figured out I will detail it here. In the meantime, I can report that the first beer is currently in the fermenter and holding steady at 67 degrees F in first stages of fermentation.