Search the FR for rkuk and B_va
basically, iirc, when the wall wetting model is showing a very large negative(?) correction, switch to the other TEMIN.
I could be wrong on this, its off the top of my head.
Thanks, I always get lost in the FR but I had a look and some googling to translate a few things. There is reference to a "wall wetting model" in there but without the bigger context of what that means it remains challenging.
B_VA ==> bedingung verzögerungsabmagerung (anzeige)
that gets translated as "condition of deceleration emaciation (display)" which doesn't help either.