probably air locked if you've been draining system. is the f+e tank allowing system to refill, did rads bleed ok. do you have a vent off point in cylinder cupboard.
iain, June 2008
thanks but it is not a combi boiler
john mannion, June 2008
Combi boiler? You'll have to increase the water pressure to around 1 bar by opening the filling loop before the thing will behave itself. Keep an eye on the pressure gauge and don't overdo it!
