hi i have added a radiator to my current system wich runs on 10mm piping i taped of the closes radiator to were i was putting the new one i did it with push fittings if i tern off a the ather radiators an it gets hot but as soon a ipother radiators it gose cool i have throtled all the other radiators right back but this dose nothing i have also changed the pump to a more powerful one but its no deferent please help
