The Sime is a superb boiler, I have one myself. Somewhere down the MAIN COLD WATER INPUT pipe there will be the filling loop. This should be an armoured pipe running between the COLD INPUT and the HEATING RETURN. depending on the variety of the filling loop you may need to either just turn a tap or you may need a screwdriver to open the valve. Becareful, watch the pressure guage as you don't want to achieve more than 1.5bar (max)
Some installers years ago did not install the armoured pipe. so you may find two regular bibcocks if so carry-out the same procedure but do it very gently. remember 1.5 = maximum when the system is cold.
Townteck, August 2009
