One radiator not working: Junker gas heated hot water

avirab

The radiator is the newer style flat-panel. The water-pipe leading to it is hot, but the radiator is not; the other radiators (old style) are working.
There are two knobs at the bottom not one, see photos. One knob is truned to maximum. I see that inside the other one there is something kind of circular but open-topped, maybe it needs to be turned for the radiator to work?
What else could be the problem?
Thanks!

neilc

what about the top corners?
any air vents, or plugged holes up there?

you have hot to the left most white knob, and think it's wide open ?

is there any heat across the bottom of that rad, going to the right?

Derheatmeister

You must be in Europe with a Junkers...
Either way your rad is possibly Air locked..
In europe we would turn off the system circ/boiler and use a little air purging wrench to get the air out of the Rads
The wrench looks like this