Well I turned off all the radiators I could (one has a seized valve - I tried until I felt the metal on the valve starting to give) and lo and behold the cold radiator has gotten hot!
I would never have tried that - thanks very much
Was this trapped air? And do I now turn all the rads...
Thanks for the responses!
Its an open system (with the expansion tank etc) - it is full now (after untying the float etc) and I can hear it filling up when I bled the rads (less now as hardly any air comes out of any of them anymore)
I'll try turn all the other rads off tomorrow morning...
Hi
I've recently drained the CH system so that I could replace a damaged rad valve upstairs.
I've done this and refilled the systems - all the radiators upstairs and down are working bar one.
I've bled all the radiators (including the problem one) and I can hear water flowing into it...