I had a Ravenheat csi 120 low nox condensing combi fitted about 2 months ago. All was going well until last night it cut out with a #14 fault (flame simulation) after resetting it was working ok again. Then tonight it cut out altogether, after inspecting the PCB the main fuse ( F1) had blown so i replaced it. But now it wont fire up, the pump and fan are running but its not firing at all. Any help would be greatly apreciated!