Best Climate: Tips & Solutions

Hello everyone!
I'm having a small problem with the air conditioning in my Skoda Fabia 1.9 TDI PD, manufactured in December 2001.
'When I drive with the air conditioning on for an extended period, it starts to hum and make strange noises. As soon as I turn it off, the noise disappears. If I turn it on again, it takes a little longer before it starts humming again!'
The tensioner for the crankshaft timing belt is in good working order.
The free play of the Lima is also within acceptable limits.
Climate cooling, I.O.

Oh, one more thing!
Is it normal for the timing belt to start becoming extremely porous after only 30 months and 52,000 kilometers? It's supposed to be replaced at 90,000 kilometers!

Can someone give me a tip?
React to the sound!

In the early production years of the Polo 9N, which had largely the same engine, the expansion valve of the air conditioning system was often defective, more so than average. During a test drive of a 9N with a 47 kW gasoline engine, I immediately noticed it – it made a hoarse, whining noise (difficult to describe, but annoying).

At least in the Polo forum on www.polo9n.com, this is a frequently discussed problem...

I would keep a very close eye on the ZR. You surely know what depends on it.