Hi,
I have a 96 E230 W210. My car's temp was usually running at 95-100 even in cold weather. My mechanic said it was a faulty clutch fan.
I just went to an aftermarket Mercedes parts shop and sold me a TRUCKTEC visco fan which they claimned as a TROPICALIZED version. it is a replacement (made in Germany) part with a mercedes part number reference.
The part is cheap at around $92. The Sachs version was a lot more expensive.

Now, the car runs at 80-82 even in traffic with the A/C on.