Perhaps there is an air lock in the system somewhere. Try turning off all the radiators and run the pump for 10 minutes to force out any air trapped in the pipes. Then turn on one rad at a time - the coldest one first and hopefully it will heat up.
Neville Hobbs
January 2009
I can answer this question...
keep bleedin rads but still not heating up - is there a simpl answer to thi?
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