Beer keg tapping systems work by maintaining constant, controlled pressure inside the keg via carbon dioxide or nitrogen. The same pressure also dispenses the beer when a valve on the tap opens -- similar to a garden hose in principle. Hooking up a beer keg is a straight forward procedure that involves connecting the beer line to the beer-line intake valve located on top of the keg. Only hook up chilled beer kegs (below 38 degrees Fahrenheit) – beer begins releasing carbon dioxide at temperatures above 38 degrees Fahrenheit, and bacterial growth begins at 50 degrees Fahrenheit.
Remove the cover from the beer-line intake valve located on top of the keg. Turn the tap to the “Off” or "Closed" position.
Line the notches of the key coupler at the end of the beer line with the slits in the beer-line intake valve on top of the keg. Press down and turn the key coupler clockwise until you hear an audible “click” indicating it connected properly to the keg.
Prime the tap by pouring two to three pints of beer or until it flows smoothly from the keg.