Another cold radiator query (does not keep heat)

[Hajj]

Hello,

I have a central heating radiator that heats up nicely from top to bottom but it does not keep its heat. When boiler stops pumping hot water it turns cold very quickly. All other radiators in house are fine. Any ideas what the problem could be?

Perhaps rusted up on inside so does not have enough water to keep heat?

Thanks!

 

[CBW]

Might just be a balancing issue.

 

[Hajj]

Problem is now solved. At first I thought it might be an air lock issue after reading another thread
https://www.diynot.com/diy/threads/one-radiator-heating-intermittently.476481/

But I realised the TRV was loose so tightened it up but radiator went off again. I loosened the TRV again (but this time even more than before) and now the valve is fully open. So seems like the TRV has seized up a bit.