Cold Radiator

[clarkey]

All of the rads in the house are working fine except one, which has recently stopped working. I have bled the system, changed the thermostatic valves, tried with all other rads off, still no joy. both pipes going to the rad remain cold until i bleed the rad, and then only the return pipe warms up, but rad stays cold. Any thoughts

 

[JPC]

sounds like ur flow pipe is blocked.
is it microbore. ?
the manifold can accumulate debri and block a pipe ?


undo the rad at the flow side.....empty (close off rad valves) the rad.
open the flow valve over a pan or similar and see if anything or much comes out. if hardly anything comes out u know its blocked...trace it back under the floor and see if u can spot anything obvious