When a tap starts pouring foam, temperature is one of the first things to check. Beer that’s a few degrees too warm in the keg lets go of its CO2 in the line and comes out of the faucet as foam. Most draft systems are designed around 36 to 38 F in the keg cooler. Put a thermometer in a glass of water inside the cooler and leave it overnight. If it reads 42 or higher in the morning, the cooler’s your problem.
If it’s right where it should be, the refrigeration’s probably fine and the gas pressure or the lines are the next thing to look at.
Direct draw and long draw
With direct draw, the kegs sit in a cooler right under the faucets and the lines are short. The cooler’s the entire cold side of the system, so the repair is usually straightforward: a fan, a thermostat, a dirty condenser or a refrigerant leak.
Long draw works differently. Beer runs from a walk-in or keg room out to the bar through a trunk line, and a glycol power pack pumps chilled glycol alongside the beer lines to keep them cold the whole way. If the taps nearest the keg room pour fine and the far ones foam, or every tap gets worse as a busy night goes on, check the glycol side. Look at the bath temperature if your power pack shows it and listen for the pump. Low glycol or a pump that’s quit will warm the lines, and so will a refrigeration fault in the pack itself.
Back bar coolers and ice
Back bar bottle coolers live in tight spots with almost no airflow, and they get loaded with warm cases right before the doors open. Their condensers clog with lint and dust quickly. If one runs all night and the bottles still feel cool instead of cold, pull the front grille and look at the coil.
Bars go through a lot of ice, and the machine often ends up in a hot back hallway or a storeroom with no ventilation. Ice machines are rated to produce less as the room gets hotter, so if production drops on hot days, the room might be the cause. Slime in the bin or the chute is a cleaning problem, which our post on ice machine slime and mold gets into. Repairs are on the ice machine page.
Taproom keg rooms
A taproom cold room full of kegs mostly gives trouble when the door’s left open during a delivery or the condensing unit is fighting a hot summer. For the box itself, see walk-in cooler repair.
