Infiniton SBS-440DAB Manual De Usuario página 67

Noise
When operating the refrigerator for the first time, it runs at high speed
to cool down quickly and the sound may appear to be louder. When
the internal temperature falls below a certain level, the noise fades.
If you have the impression that something is bumping into something
else inside the refrigerator, this is normal.
This sound is due to the high speed operation of the compressor.
These are normal noises.
Hot compressor
In operation, the external temperature of the compressor is above 80 °C.
Please do not touch the compressor as this can cause serious injury.
Compressor running for a long time
When the ambient temperature is too high or when too much fresh
food has been placed in the refrigerator, it takes time to cool the
refrigerator and for the appliance to operate at the desired temperature.