Cicerone Certified Beer Server Practice Test 2024 - Free Beer Server Practice Questions and Study Guide

A foam-on-beer detector must be reset after changing a keg because this is when the beer line will be most likely to have air in it, and the detector needs to be calibrated. Resetting it before changing a keg or before service is not necessary because there is no guarantee that air will be in the beer line at those times. Additionally, resetting the detector after service, at the end of the night, may not be effective as the beer line may have already been used and adjusted throughout the night. Therefore, resetting the detector after changing a keg is the most accurate and efficient time to reset the foam-on-beer detector. The other options are incorrect because they do not take into account the potential for air in the beer line.