Hi everyone. I've got a Baxi bermuda back boiler. Recently i turned off the stop cock and drained hot water from system whilst i changed some pipes around. Like an idiot i left bolier timer to come on whilst it was empty of water. Since this day the bolier bangs quite viciously when 1st fires up for hot water. this lasts about 3 min but enough to wake me up! Its ok when central heating it on at same time though. I've tried draining system (without call for hot water!) and problem still there. Any ideas?
