Cold Radiator

Anyone know why a double radiator would be cold in the middle but both ends and the top heat up. What can I do to fix? I have bled it already.

The prob could be that the range or boiler etc could be overloaded and not able to heat anymore rads.

The radiator can get cold in the middle due to a build up of sludge. The hot water flows over the sludge, hence it is hot on the inlet, outlet and top.

the solution is to take the rad off the wall and clean it out. An easy DIY job of you are willing.

I'm not an expert, so someone may pipe in with other possibilities.

Sounds sludged up to me!

Problem is that the sludge will be all over the system, not just in one radiator and so it may be best if you have a powerflush done.

I don't know anyone round here that does it, but I found this-

[broken link removed]

The price varies a lot !

Hi Kieran, your Thread is very similiar to mine a couple of months ago. First of all lets say u live in a typical semi detached and the rad is downstairs. Turn off all the rads in the house when the heating is off and preferbly cold. Open the first rad and switch on the heat. when that rad is fully heated up proceed to the next rad and open that on. Close the first one and wait until this heats up. When that one is heated up go to the next one and open that and close the second one and continue this process until you reach the last one and when you do , lets say the final one is nice and hot and heat is on (making sure all the others are closed) you can bleed it . Hopefully the air will hiss out nicely and solve your problem. What you were doing was making you heating system think that it had only one rad on its circuit and moving whatever air up to the top via water pressure.
If this does not solve you problem the valve to the left of your imersion tank up stairs is either opened too much or closed too much. And this maybe tgat the water supply is flying thjrough the coil in the rad. Dont go to the expense of changing you circulating pump Like I did. I done that and didnt work. wasted plenty of nights trying to solve it. Called a plumber and sorted it within 5 minutes. Handiest job for him all day. Sorry I went on but I hopw I helped you. Let me know how u get on

Hi Kieran,

You may find something useful here.

Thanks to you all. The problem was sludge. Although after I spent about an hour flushing it out in the back garden I discovered the bleed screw had been sheered off, so I ended up getting a new rad anyway.
Thanks, Kieran

Kieranb said:

Thanks to you all. The problem was sludge. Although after I spent about an hour flushing it out in the back garden I discovered the bleed screw had been sheered off, so I ended up getting a new rad anyway.
Thanks, Kieran

Click to expand...

Whey, hey, do I get a prize?

And as Alfy said, consider the fact that it may not be an isolated one. The other rads could be sludged up as well, to varying degrees.

And in the cold this morning, you need all the heat you can get.