I've got a Baxi Solo 2 40RS model (boiler) which would not fire up when turned on . The reset button wasn't activated when I checked it. I can turn it on by using the gas control knob (which does not pop back out when pressed). The pilot light does not ignite from the main switch. When I do manage to get it going, it wont fully turn off not unless I turn the gas knob off. What do I do?