HI CAN ANY BODY HELP I HAVE A FERROLI MODENA 102 COMBI CENTRAL HEATING BOILER .THE HEATING WORKS FINE BUT WHEN YOU NEED HOT WATER IT ONLY SWITCHES OVER FOR APPROX.30SECS IN WHICH TIME YOU DONT GET MUCH HOT WATER IF YOU RUN THE HOT WATER TAP IT WILL KEEP SWITCHING THE BOILER ON ONLY FOR 30 SECS APPROX.ALSO CAN ANY TELL ME WHERE TO GET A USER MANUAL AS MINE HAS GOT LOST.........