First apologies if this isn’t the right subreddit for this sort of post.
I just moved into a new house recently and one of the radiators won’t stop running, I got it on the lowest setting (frost) and that doesn’t stop it, when i put it up to 1 it becomes even hotter. It is currently about 40-45 ish °C on top and about 20-25 °C on the bottom.
What could the problem possibly be? (the controler is Heimeler thermostatic head D)
Picture of the radiator in question: https://imgur.com/a/tsUkTQ7