Regular cleaning of the faucet, beer hose, and keg coupler is extremely important. If this is not performed, the beer will foam. Additionally, bacteria, yeast, calcium and mold, will build up and quickly degrade the quality of draft beer.
Pump water mixed with a cleaning chemical into the beer hose and let it soak for the time prescribed by the chemical manufacturer.
Then, thoroughly flush the beer hose with water to remove all traces of the cleaning chemical.
The last and most often overlooked step is to soak the keg coupler and faucet in water with cleaning chemical then brush them clean with a cleaning brush. Rinse them completely clean with water.