Radiator warm at bottom

[markcoc]

Help,
I have a problem with one of the downstairs rads - getting hot all over except middle-bottom where it is only warm. No air lock in system as all bleed ok. Pump ok, boiler ok.
Any ideas please.
System is regularly maintained anually

 

[JPC]

a build up of sludge could be ur answer

 

[markcoc]

If I turn of all other rads,turn system back on, would this 'flush' any sludge elsewhere and block pipes leading to the next rad. Would I be better off closing inlet valve to rad and disconnecting other end to empty out possible blockage.

 

[JPC]

if u want to clear it (or try) close off both rad valves (hopping they actually close). crack open the nut nr the rad and drain the rad.

open bleed valve to allow air in and drain quicker.

take rad off completely and take it outside and try removing the sludge with the hose pipe on full wack.

carefull where u do it as the sludge is black/brown and likes to stain stuff

 

[markcoc]

Thanks very much - valves all work ok, will try what you suggest.