I have a closed system run off a combi boiler. The radiator downstairs is always cold even on high setting on the rad thermostat. I have bled it and the water comes out clean yet it remains freezing cold and the water coming out also is cold yet all other rads work. Any ideas ?
If so, you take off the bit with the numbers and find the pin in there. Or get a friend to do it for you. Just pull the pin out and put it back in - you want movement in the pin.
Look at where it joins the radiator. Do you see where it clamps on - unscrew the screw holding the clamp tight. Take the numbered bit and clamp assembly off. Do you see the pin? Pull it out - probably need a pliers. Put it back in - then press it - does it feel like its moved in? Now put the numbered bit ack on, tighten it and finger crossed it will work when you turn it.
Any luck with the pin Flitters?
It should spring up on its own after you've removed the head (knob with numbers on it).
If it's stuck down, tap it a few times with a mallet.