Three of the radiators remain cold. I've called in a Plumber who added a solution to the tank and flushed it after a week but the problem remains. I've drained each of the radiator to no avail. Do you have any advice as to what else I can try to rectify this problem?

Steve Lai, December 2008

try shutting down every other rad in the house except the one youre working on,do that for all three rads individually and see if they heat up,if so then it's a case of gradually restricting the flow to the warmest rads to force the water through the colder ones.

steeveepee, December 2008