Climate Control Noise

[y5stu]

Hi, recently purchased an ex demonstrator 207 HDi 92 Sport with Sat Nav and have encountered the following problem...

After 15-30 minutes of driving with the climate control on and set to about 19 degrees you can hear an underling noise. The noise is dry and whines at higher revs but goes completely when the climate control is turned off. It is most noticeable when you pull away in first gear or when changing down from 3rd to 2nd. I believe it to be the air con pump (often referred to as the condenser) but could it be anything else. Is there a belt that needs adjusting?

The car is only 12 months old and has been quiet until now. The supplying dealer has looked at it but doesn’t believe there is a problem, I disagree, the noise wasn’t there before and they seem reluctant to replace anything unless they hear it despite it being under warranty.

Any help and ideas much appreciated.