Radiator partially cold (Possible sludge built up)

[SALL2009]

One of the radiators on my combi boiler central heating system is cold at the middle bottom. I have drained it and the water inside was very black. I have put Sentinel X400 in the system and after 2 days it’s still not improved. And still cold in the same place.

What other option can I try? I can not afford a power flush at the moment. Any suggestion would be much appreciated.

 

[seco services]

take it off and flush it through.

 

[Biguns]

Err start from the begining:- are both valves open?

 

[SALL2009]

Err start from the begining:- are both valves open?

I think so, Most of the radiator gets hot quickly. Only part of it, doesn't get hot at all.

 

[45yearsagasman]

Then do as Seco says.Remove rad to outdoors and attach mains pressure hose and flush it through.You may need assistance depending on rad size as it is best turn and somehow shake rad to dislodge stubborn blockages.I've done loads with great success.

 

[SALL2009]

Would this be worth trying, if I leave the radiator attached and attach a hose pipe to the drain tap (in the pipe work just after the radiator) and open the filling loop and flush out the radiator that way? I can tap the radiator with a rubber mallet to shift the sludge.

It might snow on the weekend, so would be a bit awkward to do it outdoors.

 

[Burnerman]

Unfortunately you wouldn't shift much muck that way....as suggested, the best way is to close off both valves, drain the rad down and take it outside to the hosepipe.
John (4" snow here )

 

[SALL2009]

Expected that answer, But don't like it lol.

I wouldn't mind 4" snow on a week day. Probably get the day off lol

 

[Biguns]

Have you tried turning all other radiators off and this one full on with both valves, making a note of how many turns you make on the lock shield valve for re setting purposes