I removed one radiator without following any procedure water all over the place and when i put the radiator back the boiler pressure was at zero. Their is no plastic key for this model but has a filling loop fitted with two valves.
On opening these the gauge rises very slowly to 1 bar but when closing the valves the pressure drops to zero with water coming out of the overflow pipe outside.
Tried bleeding radiators but no air or water coming out.

Thomas, November 2012