How does The SUB work? | Beerwulf
HOW DOES THE SUB WORK?
A brief introduction
The SUB beer tap is easy to install and even easier to use, but how does the device actually work? How does the beer come out and how does the beer stay optimally fresh in the SUB Keg?
How does a SUB Keg work?
Let's start at the beginning, the SUB Keg. SUB kegs are plastic containers for two litres of beer, which have been specially developed for The SUB. The barrels work using the bag-in-bottle principle; inside the plastic bottle contains a bag holds the beer.
As you pour more beer, the bag shrinks further and further, this is shown in the image. This means there is no oxygen in your beer, because it occupies the space between the bottle and the bag. The double layer of black plastic also helps to preserve the quality. It prevents light from reaching your beer and keeping it fresh for longer!
The tapping mechanism
Tapping with The SUB is very easy; pull the handle down and the beer will start flowing immediately. The mechanism on the inside of the tap handle makes this possible.
The photo shows the tapping mechanism of a SUB Compact. If you have a Classic this will look slightly different, but the operation is the same. There is a plastic nozzle at the end of the tube on a SUB Keg. You clamp it in the metal slide that you see in the photo. By pulling the lever down, you push the white spout together, allowing the beer to flow out of the keg.
Important: make sure you press the spout firmly into the tap mechanism. Also regularly clean the metal slide and make sure that it continues to move smoothly, possibly with a drop of vegetable oil or in worst-case scenarios WD-40 (not too much!) on a cotton swab. This will prevent it from getting stuck in the 'open' position.
Tapping under pressure
Just opening the tube is not enough to completely empty a SUB Keg. Taps in the hospitality industry are pressurized with CO2, but due to the ingenious design of The SUB and kegs, this is not necessary.
There is a small pump in the back of The SUB chamber, this connects to the valve at the bottom of each SUB Keg. The purpose of this is to ensure there is always pressure on your SUB Keg by pumping air between the bottle and the inner bag. The beer is pushed out of the bag with air pressure, as it were.
Every now and then The SUB checks whether there is still pressure on the keg, so don't be alarmed if your tap sometimes suddenly starts making some noise. This simply ensures that your SUB is always ready to pour the next glass of beer!