Renault Megane 2 (2007) heating driver

I have a renault megane 2 of 2007 and I carry several problems with the air conditioning; I did not throw cold air, the compressor did not work, etc., all arranged in the official Renault workshop.

But for a long time the driver of heating and air conditioning has been making noise only at high speeds, I know that there are some car, some Citroën that if the drains of the water box are struck in the water box inside the driver and end up oxidizing the driver's resistance box.
In addition to making noise the driver at high speeds, it does not cool, it makes air but nothing cools.

All the best