how to fill the the boiler with water when the pressure has dropped?

hi. it seems you know how to open the filling loop to allow water through but the non return valve may well be 'kaput'. may be an idea to unscrew the loop on the cold water inlet to make sure there is water there. (turn the tap off first then open v. slowly or you might get wet)!! make sure sure the taps or screws on the filling loop valves are open on both ends.

paul
October 2010