Thank you for your answer! Here is what I got:
In the console, 3 cells are limited to 1 K, and when I use the compute button in the Field Variable Register, it also shows me the range between 1 and almost 700 K. However, trying to mark the cells between 0 and 10 K for example results in 0 cells marked (see screenshot).
Don't know if I need to mention that I use a polyhedral mesh, almost 10,000,000 cells in parallel mode, also using shell-conduction. My inlet temperature is 281 K (outdoor air flow around buildings) including radiation. The temperature should be in the range of 280 K to maybe 300 K. When I try to mark the cells between 300 and 700 K also 0 cells are marked. So in fact when I enter 280 K to 300 K, all cells are marked, but I don't really get why I get the error then. I assume there are some bad cells (although inverse orthogonal quality is below 0.88) that cause the problem, so I just wanted to see where in order to adjust the mesh accordingly.