if i loosen valve from pipe work water should rush out if not blockage in system system is 10mm flexi pipe whats best way to flush out whole system.
norman
removed rads took the outside and flushed the through with a hose pipe the boiler is old not like a combi water pump apears to be working as down stairs rads are hot
my upstairs rads where not warming up i have flushed out rads but there now appears no preasure to push out air. i have a thorn m boiler should there be a valve to increase water presure or does it just work from water pump