cold radiator - one only

[aimellie]

Recently moved rad from one wall to different position under window.
Tee,d new pipes(speed fit) from existing flow and return.Located flow to TRV valve and return to L/S valve.very restricted for space (joist) had to use flexi tap connectors.
This radiator will not get warm at all, i have bled the radiator and bled and bled,every rad in the house is hot and o.k, the system is a sealed system and i am constantly making sure it is set at 1 bar, whenever i bleed the system all i get is water and no air, i have tapped the brand new TRV valve and the pin can be pushed down in the off position but no hot water gets into the rad when released.
The pipe leading to the TRV is hot but the return is cold, i am now coming to the conclusion i accidently switched the flow with the return but i have been told it should not make a difference or it is something to do with the fact i have used flexi connectors.Someone said pressure the boiler up to 2 bar and then bleed the system ???????

please can anyone give me some pointers, after laying a new carpet i am very reluctant to gain access to the pipework again.

 

[ollski]

If immediately before the trv is hot and immediately after is cold when it's turned on full, then he's not working!

 

[ChrisR]

Get rid of the flexy tap connectors. They WILL fail. NoOt designed for 80 odd degrees.

Sure you don't have both ends of the rad off one CH pipe?
Could be an air lock on the way to the rad - turn off all other rads, to pump it out.