look on the pipe work for a filing loop. here is a image of one below. then just turn the black valves on the end and the boiler will start filing up. just get it out the red and close the valve. some have one valve some have two valves so look out for this.
https://www.google.co.uk/search?q=filling+loop&es_sm=93&source=lnms&tbm=isch&sa=X&ei=nG5QUtevGMbM0QWOkYG4Bg&ved=0CAkQ_AUoAQ&biw=1366&bih=667&dpr=1
kash
October 2013
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