A review of the 7 gallon version of the SS Brewtech Unitank
After 5 years of using this tank, and now having purchased a second one, I can happily talk through the pros and cons of these fermentors. I’ve also made a couple of changes to make the tanks more usable and, in my opinion, better. Read on for the SS Brewtech Unitank review.
I have updated this to compare with the newer version, as there is now a Unitank 2.0 which looks fantastic, and looks to address some of the things I’d like on my own tanks. The new version appears to be another step forward for home brewing, but the products are largely similar in operation, so this article is still relevant.
The overview
This is the 7 gallon model, which equates to approximately 31.8 litres. It is designed to ferment a 25 litre batch with appropriate head-space to accommodate a generous amount of krausen. Being a unitank, the idea is to be able to ferment, carbonate, crash cool and serve/bottle from the same vessel. Because of that, this vessel is able to withstand a working pressure of 15 psi, and a maximum tested pressure of 30 psi.
There is a safety valve on the top, which, in my experience, will release pressure somewhere between 16 – 18 psi, and continue to release pressure until it seals again around 15 psi.
You will also see the chiller coil attachments for connecting to a glycol chiller unit. I’ve gone for a quick disconnect system where I can un-clip the flow and return on each side, then clip them to each other. This way, there can be no chance of dirt getting into the connections if I’m cleaning the tank on the lawn. The connections are self sealing and non drip, so there is no leakage of glycol.
There is a 3″ tri-clamp opening which is where the tank can be filled with wort and is also useful for adding dry hops, yeast or fining agents etc.
Chilling
Opening the 6″ triclamp, it reveals the glycol chiller coil. On the original version I have, this coil is too short. Which means if I want to do a small batch, then the smallest amount I can chill is around 14 litres, as the coil only has about 2 turns in the liquid at that volume. The second tank I bought has had this issue addressed, with coil being about 2 coils longer. I can do smaller volumes on this, but more importantly, it also chills a full tank noticeably quicker. I was quite disappointed and annoyed at this oversight by SS Brewtech on the original, so I’m glad this is fixed.
Cleaning of the coil is one of the more awkward parts of turning around the tank between beers.
Version 2.0 has got rid of the coil, and now has a professional quality chilling jacket. I’d love to get my hands on one of these, as I think this will be a game changer.
Cleaning
The 6″ opening is roomy and makes it extremely easy to get in to clean. Getting to the bottom of the tank with a sponge is easy, and the idea of using a CIP on something this size seems like more trouble than benefit.
All fittings on the tank are 1.5 inch tri-clamp. This makes it easy to assemble/disassemble and cleaning a breeze. All the welded connections on these are of excellent quality. The welds have been ground back inside the tank and polished smooth.
The components
The blow-off cane is about as far to the top as it can be, I’ve never had a blow-off on the tank, as the head space is more than adequate, if brewing no more than 25 litres.
The blow-off cane is the only weld on the unit that is not ground back. It is where the T comes off to the pressure gauge. The weld is inaccessible, so is not ground down. There should never be any contact from here to the beer, but it is worth some attention when cleaning.
The pressure gauge is generally fine. My original gauge has gone out of calibration by 1 psi, and won’t come back in, even when opening the rubber breather valve on top.
My original tank pictured here has a well positioned Pressure gauge attachment. On the second tank however, the T section has been welded too close to the tank. This means it is extremely difficult to put one of the SS Brewtech clamps (pictured below) on when the tank has the neoprene jacket on. I have to use a cheap chinese clamp which is much smaller, and is the only one that fits easily.
The thermowell on the front fits the FTSs system well, and there is a shelf option that can be purchased to hold the FTSs unit on the front of the tank.
Oxygen free sampling
An overlooked part of fermentors is the ability to sample from them without introducing oxygen. The SS Brewtech unitank does this with with a sample tap. It’s been very reliable and is easy to clean. It can be disassembled with a spanner and cleaned in a couple of minutes. Generally I don’t even disassemble it. I have a small brush that can get in from both sides, and with some PBW run though it, the internals remain clean. I open it up perhaps every 15 brews, it’s never been dirty.
Racking
The racking arm is effective and has not caused me any real problems. It turns down to get all but about a pint of volume out of the unitank. I ferment with this turned to the side, but slightly down, so as not to fill with falling yeast.
When it comes to bottling, after draining the yeast to a level where I can see clear beer in the sight-glass, I turn the valve to the down position and do a clearing run of beer. I then turn the valve straight up, as there is a pocket of gas that gets trapped in it. When bottling with the Blichmann beer gun, this gas pocket sends small bubbles through the beer line and causes frothing in the bottles. With the racking arm turned upwards, it purges this gas pocket out, and bottling is faultless. Just remember to turn the arm back down before getting to the end of the beer….
You can see below, the level that the racking arm will draw to, leaving about a pint or so in the bottom.
Racking issues?
The racking arm can have some problems. For me, I find it easy to pinch the two o-rings when putting the arm into the valve body. It regularly requires a couple of tries to get it right. Some have also reported that the arm can get caught when rotating, and the arm position may be lost, which results in not getting the full volume from the tank. All this seems to have been solved on the 2.0 version. It may be tempting in the future to upgrade my tank to the new option in the future.
The valve body is very solid, and excellent quality. The bug bear for me is that it is difficult to clean and requires a specific brush to clean it, else it needs disassembling. Once again, this is solved on the 2.0 version.
Sight-glass required
One of the modifications I have made, which for me is an essential, is to add a sight-glass. I have gone for the smallest sight-glass I could get. To fit this to the tank, I have had to reverse the bolt and tray arrangement on the bottom of the legs. The other option would be to get the leg extensions. However, this tank is unstable enough on the short legs as it is, and I keep my tanks in insulated cupboards, so I don’t want that extra height.
The bottom outlet gate valve is the same tough quality as the others on the tank. It’s easy to drain/harvest yeast or to drop dry hops out before fining.
Carbonation
The original carb stone was, at best, just ok. It had too small a surface area, and was not able to be disassembled for cleaning. This was obviously noticed fairly quickly, and the second tank I bought had a new carb stone. This version can be fully disassembled, easily cleaned, and has a much larger surface area. It makes carbing up the tank fast and reliable. It’s such an improvement, I quickly replaced my old one with this version.
After cleaning the carb stone with PBW, I give the stone section a quick boil to kill any yeast that may be inside the structure.
The original valve on the blow-off cane was a ball valve. It was fairly low quality, and started leaking. It seemed like a money saving afterthought, and seemed out of place on what is otherwise high quality equipment. I replaced it with another gate valve. I’ve never had any issue from there on in. I notice that the version 2.0 is a better ball valve than the original, and is capable of full disassembly/servicing.
I have purchased a spunding valve for one of my tanks. I admit it is not SS Brewtech. It’s straight from China. About 1/3 of the price, but has been faultless. Regardless of which version you get, I would recommend this as an addition to anyone’s Unitank.
Keeping Cool
The Unitanks come with a neoprene jacket, which is essential for holding the heating mat against the base of the tank. It also helps with insulation. I used it this way for the first year, but found that my glycol chiller was running all the time during summer, just trying to keep a lager cool. Also,the jacket was always soaked due to condensation, which lead to mould growth.
I quickly built some ‘cabinets’ out of insulation board. These have front and top panels that are sealed with magnetic strips. They are more efficient than fridges, due to the thickness of insulation, and has cut the run time on the chiller to a fraction of what it was.
In closing, I think these are fantastic pieces of home-brewing equipment. They make limiting oxygen exposure a breeze, and they allow controlled fermentation easy. They also bring a professional level of hardware to the home brewer. There is a version 2.0 out now, and one day I am hoping to get my hands on one of those, as I’m wanting to add an extra tank to the brew-room. Yeah, greedy, I know….