The radiator in our bedroom does not warm up. I removed the thermal adjusting "thing" to expose the pin. The pin simply slides in and out as I would expect it to do. In or out, the radiator does not warm up. The radiator in the kitchen was the same, but removing the "thing" and pulling the pin out, gently of course, corrected the radiator and it functions normally now. What should I do to coerce the radiator in the bedroom to begin functioning again.