by nitro23456 »
Thu Apr 03, 2008 10:53 am
most likely sludge build up inside the rads. difficult to say 100% with the info provided though.
How old is your system and has it been flushed recently?..... if not for years it is likely sludge build up and the remedy would be draining and power flushing the system.
if it is one or two rads you could isolate them, take them off and hose pipe them through in the garden until water is clear. However sludge is like a spider - where there is one there is more.
hope that helps.