Irrespective of the model, whether it is a well-worn Samsung fridge, the unit will make noise during operation, since it contains moving elements. The motor with a crankshaft rotates, the crank with the compressor piston makes a reciprocating motion and the valves knock at actuation.
The volume increases in models equipped with the No Frost system due to the operation of the fans. Owners usually get so used to the sounds made by a normally working refrigeration unit that they do not notice them. But if it begins to remind of itself too noisily, it is necessary to understand why the refrigerator hums.
The maximum noise level produced by the refrigerator is limited by GOST to 55 decibels. That corresponds to the volume of a normal conversation. Manufacturers of modern units assure that they have reduced this value to 40 dB. When buying, you should read the contents of the label on the front. The top line shows the power consumption class, then the volume of the chambers, and at the very bottom the noise level in dB.