fuel saver 55f will not work every time?

i would take the case off and check the current to the fan, with a multimeter or at worst a neon screwdriver, if power is continuous but the fan stops and starts, your fan motor is at fault, if power is presant for only a second then cuts out, its probably the pcb or a supply lead, carefull not to touch any live connections when doing this and have someone at hand to switch power off in case the boiler does decide to fire up when you take the case off

john
February 2010