Dirty condenser coils do not fail loudly. They raise discharge pressure, lengthen compressor run times, and gradually push a freezer toward a thermal alarm while the box still feels cold. In more than twenty-six years of commercial refrigeration work, I have seen coil neglect turn a 20-minute service call into a compressor replacement. The cleaning procedure is simple, but the sequence matters. Rushing a vacuum across the fins, using the wrong brush, or spraying water into a powered unit creates more risk than the dust it removes. The sequence below covers the cleaning steps, the tools that avoid fin collapse, and the inspection points that tell you whether the problem is maintenance or something deeper.