Measurements of the surface acoustical intensity have been made on a large centrifugal chiller in order to determine the major noise‐radiating areas of the machine. In addition, an examination of the coherency of these major noise‐radiating areas has suggested that the total noise power can be obtained by addition of the noise power outputs of each component. The measurements were limited toA‐weighted sound‐power levels. The feasibility of the method has been checked by calculating the radiation efficiencies of the two dominant noise radiators. The values were found to be consistent with current knowledge of sound radiation from flexural waves in plates. Similar calculations based only on nearfield pressure measurements have demonstrated the very complex nature of the pressure field surrounding this type of large machineinsitu.