No sooner did I Buy fuel oil than the boiler falls apart. Sods law or what? The first hint of a problem was the electrics tripping out. The cause was quickly narrowed down to the boiler and taking the cover off revealed why. The Flow Switch has developed a freaky fault where water was running back up through the electrical flex and pouring on to the electrics. No wonder it tripped out! Have called a plumbing company called RightFlow.