My AC is starting to whine as i accelerate. Why?

 

It may be a bad bearing in the compressor, failing compressor, or perhaps high compressor load due to a restriction in system. Only way to know is to check system pressures and assess. Professional help likely necessary unless you are dedicated DIY'r.

good luck

 

If the compressor fails will it damage snything else important?

 

If compressor seizes, the belt may break which also drives the alternator. Engine will run but if lights are on, not for long.

A seized compressor may cause debris to be scattered throughout AC system requiring replacement of entire AC system to repair.

good luck

 

Two other items it may be is a bad or improperly tensioned belt, or a bad bearing in the compressor pulley.