Radiator colder at the bottom

[DIYspanner]

Its a Myson 600mm tall x 900mm wide Type 22 fed by 10mm push fit and has been in service since about 2003/07 when the house was built.

I've watched a number of videos on YT about sludge at the bottom and removing/flushing the radiator. Some recommend light hammering with a rubber mallet whilst flushing to get the sludge dislodged.

I've tried the tips, flushing with the rad upright and upside down while tapping the bottom with the mallet but not much black sludge flushing out.

Rad is back on the wall, connected and bled but still not getting hot at the bottom, really just lukewarm.

Can anyone recommend other tasks I can try please?

 

[Jurassicspark]

Sounds like a balancing issue.
Try turning off other rads and see what happens.

 

[tincup]

The sludge could be in the pipe feed or return.

 

[DIYspanner]

Apologies, I should also have mentioned the rad acts as the bypass rad for the system. Its the only one without a thermostatic valve.

The lock shield valves on all the other rads are open by not more than a turn, some only 1/2 turn.

Being the bypass rad, both lock shield valves are open about 2/3. As suggested, I will experiment closing other rads.

Thanks!