All radiators hot at the top, lukewarm at the bottom

[ptwright]

Hi,

All my radiators get hot (can't keep hand on for more than a second) at the top, but only get lukewarm at the bottom (can hold hand there for a long time). I don't think it is sludge as they are all the same. The flat is a 90's conversion with seven radiators. The boiler is a Vaillant from about ten years ago. Is this likely to be a balancing issue, a pump issue, or something else? Any help appreciated.

Thanks.

 

[jdstratton@btin]

Suggest the best way to check to confirm not sludge is to remove one Rad and flush through outside with a hose . If its 1990s with no maintenance since a good chance it will be sludge IMO.

 

[diamondgas]

Poor circulation/slow flow will give you something like what you mention. If one pipe on all the rads is red hot and the other cold then circulation, if both relatively the same in temp then big cold spots (sludge) thoughout!