You will not get any water to your rads unless you pressure your boiler back up, this is between 1 bar and 1.5bar .Underneath your boiler [usually] there is a filling loop in the form of a steel bradded flexible tube. You may see a small tap on this,or the pipes could be rigid in which case you may be able to see something like a joint in the pipe-work of which there will be a screw on the front. Turn either the tap or the screw inline with the pipe and watch the pressure gauge.[Don't forget to put them back to the original position].The leak that you cannot see will definitely be there it only as to be very small for the boiler to lose pressure.
Mic. H, October 2007
