This thesis deals with the analysis of the sound radiated by a household refrigerator when a reciprocating compressor starts its operation. The study was developed based on theoretical analysis by means of numerical simulations and on a phenomenology basis by means of experimental tests performed on a real refrigerator under transient conditions during its startup. The simulations was supported on the Finite-Di_erence Time-Domain method for modeling airborne and structure-borne sound phenomena and the measurements were carried out in an engineering acoustic chamber with semi-anechoic characteristics. The main objective of this work is to estimate what are the paths of principal contribution to the sound radiated by the refrigerator under transient operation: directly through the air or indirectly from the compressor through the structure cabinet of the refrigerator.