So that's unfused and could be fused via another switch, or it's direct to the consumer unit, which wouldn't give the best protection. You haven't knocked a switch off anywhere have you? Seems more likely that the internal fuse has blown.
I went to put the heating back on via the white switch next to the honeywell. The heat didn't come on. At the same time the weather was hail stones and suddenly awful outside. Went to check the boiler, it was off.
Those were the only two things different than usual. I've been using that white switch inside the kitchen for the past week (as it's been getting warmer so I mostly kept it off to stop the running charge for gas).
All the switches on the fuse box are on. Do you suggest I try a full reset there or anything else?
The only other thing I can think of, is that rodents have been spotted in the area and I saw one coming out of my garage the day before. Possible gnawing chewy situation up in that roof?
The hot water was still working minutes before all this happened.
Buy yourself a 'voltstick', and learn how to make use of it. They are a very safe way for the unskilled to see what is live and not live, without needing to open things up, or disconnect things.
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