This post was updated on March 2nd, 2017. The main changes revolve around a decision over pump selection. The parts list was also updated with parts found to be cheaper than what was there previously.
This post was updated again on June 12th, 2017. The change involves a switch to a higher rated power supply.
It isn’t often that I need to carbonate a beer quickly, but at least a few times a year I find myself pressed for time and needing a beer ready to serve NOW! At the 2016 HomeBrew Con I remember looking longingly at Blichmann Engineering’s QuickCarb™, an inline carbonator, and while I’d love to own one the $180 price tag is just a little too steep.
I didn’t think about it again for a while until recently, when I kegged my mild that is bound for the first round NHC judging in Milwaukee. The problem is I had only a week to carb the beer properly and I much prefer to do so over time than burst and shake. I always seem to over carb my beers when shaking, and I’ve also recently been told that excessive shaking has the potential to degrade head forming potential. Since this beer is going to a competition, I’d rather make sure everything is as perfect as possible, so shaking is out.
Fortunately the mild is an English beer so lower carbonation levels aren’t a problem and I generally aim for about 2 volumes of CO2 for my English beers, so this time I was OK and able to get the beer carbed, but in the future will I be so lucky? This got me wondering what it might take to build my own inline carbonator setup, so I started to put together a parts list to find out.
Breaking Down the Carbonator System
Looking at Blichmann’s setup, the first thing you probably notice is the pump, and this is going to send up the price tag alarm in your brain – it did for me. I briefly thought about a carbonator that worked by pushing from one keg to another, but since the Blichmann system runs the same beer through the lines for an hour to get it carbed up, I figured that wouldn’t work so we’ll need a pump.
The Blichmann available carbonator uses a 12V, 45W diaphragm pump capable of 4L/min, and fortunately exactly that kind of pump is available on AliExpress for less than $20 shipped! Sadly that pump turns out to not to be made of food safe plastic, so I searched a little more and found some similar diaphragm pumps that are, but they have unusual connectors, at least when it comes to what home brewers are used to in the US. These pumps cost a little more, closer to $30 shipping. After some redditors pointed me to a couple of posts on HomeBrewTalk where others had built similar systems, I was able to see that the food grade pumps I was looking at can be made to work. An appropriate power supply, 12V 6A, was also easy to source through AliExpress.
Next I turned my attention to the carbonation stone assembly, as that is what makes the entire system work. The CO2 is turned into millions of tiny bubbles, which greatly increases surface area contact with the work and that speeds up absorption. I found a few of the bigger home brew sites selling a diffusion stone fitted to a 1/2″ MPT fitting with a 1/4″ barb on the end, which is perfect for our need. I found a few complete assemblies that inclue a 3-way stainless tee and barbs. These are intended to be inline oxygenation setups, but there is no reason they can’t work for CO2 as well. AliExpress came through again, having the same assembly for a better price shipping. I did also manage to find the components even a few dollars less than the assembly.
As a quick aside, pretty much everything we buy for building home brew gear comes from China. Don’t believe me? Look for all the parts you use to build things on AliExpress, you’ll recognise a LOT of things. Many of these same items are also available on ebay, mostly through the same sellers as on AliExpress, but I generally find pricing to be a few dollars cheaper through AliExpress than ebay.
With the two main components, pump and carbonator, found and not expensive, everything else is just finding common parts to connect it all together. Below you’ll find a mostly complete list of everything you’d need to actually build this carbonator, including links to where I found good pricing. You can, of course, change parts to fit with whatever existing equipment you have and I’m sure many of us have at least a few of these things lying around already.
DIY Carbonator Build List
- ($28.19) DC 12V 70W Food Grade Diaphragm Pump: 12v, 70W; this is higher power than the Blichmann pump, but that shouldn’t matter
- 12V, 10A power supply:
($7.02) 12V, 6A Power Supply: no need to go overboard and buy anything bigger than the pump requiresbuy a pump with an Amp rating one step higher than your pump requires at least. The 6A power supply was not enough to kick the pump on initially 98% of the time, so I switched to a 12V, 10A power supply from Amazon and it’s working properly.
- ($25.18) Inline Diffusion Assembly OR ($21.20) Individual Parts: Stainless Tee + 2x 3/8″ Barb + Inline Carbonator
- ($13.12) Gas/Liquid QD Set, with Swivels and 3/8″ Barbs: many people have extra of these, but I like to buy dedicated sets for builds.
- ($2.94) 6ft Thin Wall 3/8″ ID X 1/2″ OD racking hose: I think 6ft should be plenty, using 2 or less from the keg to the pump, and the rest to go back to the keg after the carbonation assembly. Probably fine with much less than 2ft from keg to pump, depending on your use case.
- ($?.??) A short length of beer line tubing (1/4″ or 3/16″) to connect the gas line to the stone. I’ll leave this part open ended as how best to connect your existing gas supply will likely be different for everyone.
Safety Note: this is the original pump I found. It uses ABS plastic and therefore I believe it cannot be considered food safe (also has 1/2″ BSP threads for reference). I would not use this or any pump that is not stated to be food safe. When in doubt, check with the vendor prior to purchase!