Spike Brewings brand new CF10 Conical/Unitank has finally been released. We got our hands on one and put it through a brew day to test it out!
After a year of testing and designing Spike Brewing has finally released their Conical/Unitank. The CF10 was the first size unit to come to market with the CF5, CF15 and CF30 to be released sometime in the future. The CF10 is full of great features. We got our hands on the new CF10 and put it through a brew day to test it out.
What is a Unitank and how is it different from a Conical? Looking at them side by side, you probably wouldnt be able to tell the difference. They are both fermenters and have the iconic conical shape. In a typical brewery you ferment in a fermenter, once the beer is done and clear you can transfer it into a brite tank to pressurize and carbonate. Unitanks are designed to combine the fermenter and brite tank allowing you to ferment and pressurize to carbonate all within the same vessel. So quick and dirty, the difference is Unitanks you can pressurize to carbonate, Conicals you cannot.
Temperature control is arguably the most important variable for your finished product. As a Conical you want to be able keep the temperature between 60 and 75 degrees Fahrenheit (depending on the yeast) around 32 degrees Fahrenheit at which you can carbonate beer efficiently as well as cold condition a beer to clarify it. Spike also has an optional internal chiller coil which would allow this vessel to be a stand alone. You wouldn’t need to put it into a chest freezer, just connect it a chilling source such as a cooler with ice water or a more fancy glycol chiller. The downside is the chiller coil and temperature controller are not included, they are additional purchases. You also would have to modify a cooler as a chilling source or splurge on a glycol chiller. If you don’t want to spend the extra money just drop it into your chest freezer. Here is a link to the Spikes Chiller Coil.
Oxidation is a beers worst enemy. Pressure transferring beer is the best way to reduce oxidation. Spike provides a 5/8″ 90deg barb for the lids 1.5″ TC connection that you can use to connect a gas line. You are able to push the liquid from the top using 2-3psi and out of the transfer port or lower port of the conical. This allows for complete closed transfer of liquid with minimal exposure to oxygen. Spike does suggest (its even engraved on the lid) to not pressurize the vessel without a pressure release valve. The unit is rated for 15psi and Spike sells a 15psi PRV on their site. So id say follow the manufacturers advice and get a PRV. Here is the link to Spikes PRV.
Carbonation is the big feature that makes this Conical a Unitank. Out of the box, however, the CF10 is not ready to be used as a unitank. As mentioned above Spike rated the unit to hold 15psi and requires a 15psi PRV to operate which is not included. So in order to use it as a Unitank you will need to make some additional purchases. You’ll need Spikes PRV, id recommend a pressure gauge as well as a gas in connection. Since the CF10 only has 1 1.5″ TC on the lid, we decided to go with a 1.5″ TC cross with the PRV, a sanitary diaphragm pressure gauge and a Gas Post to TC connection. This setup cost us around $120. There are many different ways you could assemble this accessory and definitely can do it cheaper, we decided we wanted to go the sanitary route and this is the setup we landed on. Pressurization is pretty straight forward on the vessel. With the gas post added to the lid you are force carbing by adding pressure to the head of the vessel which means you can monitor the pressure from the gas gauge on your tank as well as the pressure gauge mounted on the vessel. Its your typical set it and forget it method similar to carbing within a keg. After 8-12 days you should be good to go. In our case, we were carbing up a Gose and were looking for around 2.6 volumes of CO2. We set our gauge to 10psi and chilled to 35deg F and let it go. After 8 days we hit the level of carbonation we were looking for. Few things to note when using this as a unitank, make sure everything is nice and tight. Check all your TC clamps and fittings and do a pressure test before putting beer into the vessel. We didnt have any issues but im sure someone could. When pulling samples its best to turn the gas off and purge off some of the pressure. Trying to open the sample port when under 10psi will lead to a jet of beer and foam (oops). Lastly, keep an eye on the tightness of the band clamp. Every couple days we were able to tighten the clamp a few turns. We didnt run into any issues with it but we suggest keeping an eye on it. Other than that, the CF10 performed as expected and held 10psi for 8 days thus carbing our beer. It was the first time we had every carbed a beer in a Unitank at a home brew scale and the CF10 performed as expected.