The electrics have been given a sort of clean bill of health!

So pleased to see the electrician at 5 today - you never know if these chaps will turn up or not do you? It turns out our little problem was potentially a fire disaster waiting to happen. Put a chill down my spine, but at least it's sorted now. One of the main wires out of the circuit board had been simmering away nicely for God knows how long. The plastic coating was very hot to the touch and all the core wires had burnt more-or-less to powder. The electrician said we should thank our kettle blowing the system a couple of days ago, otherwise we may not have noticed the problem in time. He wasn't over-the-moon about some of the other wiring/fuses in the circuit box, but said they should be OK, just to keep an eye on them in the future. He also suggested pressing the "test" button on the main cut out switch every 3 months to keep it working in tip-top condition. Luckily it was working for us when we needed it!