There are a number of factors that can cause this, but for simplicity’s sake we can break it down into three different categories: temperature, gas, obstructions. Temperature – if the beer is too warm then it’s going to release the C02 (a.k.a. carbonation). The warmer the beer, the higher the pressure of CO2 that is required to keep the beer carbonated. Even if your cool room is nice and cold, you need to check the function of your glycol chiller to make sure it’s not running warm and ‘heating’ the beer as it travels to taps. Gas – understanding equilibrium gas pressures is extremely important when designing a draught beer system. Having too high or too low pressure on the keg can result in your beer not pouring correctly. Also using the wrong gas mixture can quickly over carbonate your kegs if not used at the correct pressure. Obstructions – usually in the way of yeast and beer stones due to lack of cleaning. Beer is a food, which means the yeast is alive and it has the ability to grow in the system. Unpasteurised beer has a tendency to do this a lot quicker, so we need to make sure we stay on top of our cleaning. Beer relies on a perfectly smooth surface in order to not release gas, otherwise it’s like shaking up a beer bottle before cracking it when trying to pour beer out of dirty lines. The seals in your system can also cause obstructions. If beer tap seals, along with other system seals aren’t routinely maintained, they can begin to protrude and agitate the beer as it passes by them.