I am a dummy....How can I top up the water pressure?

there should be a filling loop attached to the cold water feed to the boiler at the rear underside of it. The loop is a piece of flexi stainless steel pipe about 9 inches long with a small valve on. to top up boiler just open valve to let cold water in and watch pressure guage go up to recemended pressure in boiler hand book then turn valve to closed position. i am not a plumber but have done this to my own boiler in past. i hope this helps.

Rick
September 2007