new radiators hot at top and cold at bottom

jules4485

i have recently installed two new radiaors in my living room using existing feed and return pipes used for an old radiaor i removed, the problem i have is that my rads a hot at the top and warm down the bottom, these are brand new radiarors so sludge is not an issue, i have also removed the radiators and have double checked, all ok, eventually they get scortching hot for about ten mins then go cold, and the process starts again with them getting hot at the top. all the other radiators in the house are working perfectly including the other radiators downstairs, i think its safe to say i need help, i have bled gallons of water out if the system, i am 99% sure all the air is out of the sytem, the system is about 20 years old but normally works perfectly, this problem has only occured since i replaced the old radiator with two new ones, thanks jules

oldone_2

Did you replace the radiator valves, and if so are they in the same positions as on the original radiators. i.e the lockshield valve on the return pipe and the one you turn to adjust the temperature on the inlet pipe..

latecomer

I suspect the problem is that you've replaced one radiator with two and now the system isn't balanced. If its not balanced then the radiators dont get their fair share of the hot water.

jules4485

the problem occurrs though even when i have onlt the downstairs radiators on?