we recently had one of our radiators taken off the wall to replaster behind. When it was taken off, it leaked a lot of water due to a broken valve. The guy doing this work said our central heating was unusual as it was gravity fed. He replaced the valve but said when we want to put our heating on we should make sure there's water in the system first or the boiler will have nothing to work on and may break.
So my question is - how do I get water into the system in a gravity fed central heating system where one radiator has emptied itself? Thanks Claire