it is a Ferroli boiler Optima 701 made in 1995, this has never happened before and also there is a leak underneath the boiler, can anyone help me with as to what the problem could be?? really need this sorted asap, house is freezing, hwoever i can hear the fan come on, when i push the button for the pilot light to come on after following the instructions (plenty ocassions before) it just does not light !!