Other answer is wrong! The Wocester Junior has a factory fitted filling loop remove the white tray at the bottom there will be a key. Insert key and lock into position turn the grey/white knob until the pressure is up to 1/1.5bar (make sure you switch it off)
Mr Boiler
August 2009
look for a hose connecting the cold water inlet pipe and the return pipe. there will be one or 2 taps which you can open to let water in.