These are the things that could realistically be happening when one or two of your draught beers aren’t pouring. We’ll start with the most common and work toward the least common. This is applicable for both direct-draw and long-draw systems.
1. Your gas source isn’t reaching the keg. Go check that all the valves on all your gas regulators, both primary and secondary, are open for that keg. This is what a gas regulator looks like 👇🏼
2. Your gas source is empty. If you use premixed cylinders of gas, check the primary regulator and see if it has any pressure reading on it. You can also detach the regulator and just open the valve on it very slowly to see if any gas comes out, but remember NOT to open it full blast, as a full cylinder of gas is under thousands of pounds of pressure.
3. Your keg is empty. Happens all the time, so go check the keg that’s not pouring to make sure there’s some beer still in it. Pick it up and move it around slowly… you’ll hear (and feel) the beer in there.
4. Your keg coupler (or “sankey” as it’s also called) is disengaged. Happens all the time, so go check the coupler is engaged on the top of the keg.
4. Something catastrophic happened. You have a massive breach in your trunk line that’s causing beer to leak out somewhere between your keg and your draught tower. This is basically impossible, as you’d see it, so don’t worry about it, but hey…weirder things have happened.