One radiator not getting 'hot'

[jurassic sparkk]

One radiator not getting hot - well it is getting warm but not as hot compared to others.

Bled the air, cleaned the radiator loads of sludge came out, but no avail.

I balanced the rads but still no luck. There is a TRV (recently fitted) on the return side on the rad and a normal lockshield on the flow side, lockshield valve is fully open on the flow side.

ch temp is on 65 degrees. Radiator is a double panel one.

Please let me know your opinions thanks.

 

[denso13]

Turn off all of the working ones leaving just this one open. Does it work any better?

 

[jurassic sparkk]

Turn off all of the working ones leaving just this one open. Does it work any better?

Yes, it gets better.

 

[denso13]

Sounds like a balancing issue. Close all the other lockshields then just open them 1/4 turn. Just a bit of trial and error until they all get hot.

 

[jurassic sparkk]

Sounds like a balancing issue. Close all the other lockshields then just open them 1/4 turn.

cheers mate.
should I nearly close the return lockshields or nearly open them to restrict flow?

Also if closing the other radiators had no effect, what would be the cause?

 

[denso13]

should I nearly close the return lockshields or nearly open them to restrict flow?

Almost close them.

Also if closing the other radiators had no effect, what would be the cause?

Try balancing first, it certainly points to that as the radiator is ok with the others closed.