Whirring --------------
Associated with the redistribution of cold air within the refrigerator. It is probably the door to an air chute being opened to allow air to pass through. Often described as a whirring or ticking noise, it is the sound produced by a small electrical motor used to open the damper.

Air Blowing ---------
As described above the fan has been turned on even though the refrigerator compressor is still off. The air heard is the fan motor moving air to another area. Often heard within the freezer section. Air noises are also more prevalent because fan motors are quieter. Air noise accompanied by a fan running sounds normal. An air noise by itself sounds weird.

Once you have isolated the source of the sound you can then decide whether you require service. Generally, the answer is, no. Consumers simply want to be assured that the noise is normal. Or at least that it not about to break down.

Modern refrigerators have become very complex. With this complexity have come some unusual sounds. But in the end you are the person who will be living with this refrigerator for the next ten years. It's your decision.