Hi everyone.
A DIYer here, not looking to fix this issue (as the house in question is hundreds of miles away...) but to try and help owner to narrow down possible causes. He
has had a sparky in, but problem persists.
He has a kitchen in a flat-roofed extension. There is a 'reception' room in the same extension. His roof has been leaking, and water has come in through a ceiling light in the rec room, on the opposite end to the kitchen. He's having roofers out to sort this...
At the same time, tho', the MCB supplying
only the kitchen
sockets has started to trip. This is a B32 MCB and has just been replaced by the sparky, presumably to see if the MCB itself was the actual problem. It hasn't - it still trips seeming at random, sometimes during the day, other times at night. When the owner tries resetting the MCB, sometimes - usually - it remains on. He reports that he does notice a spark inside it when he does so...
I asked him to send me a pic of the CU, and that is shown below. I had been assuming that it was an RCD that was tripping due to the leak, but was surprised to be told it's a 32A breaker.
My questions, please, so he can be informed;
1) Will at 32A MCB generally
only trip when the current load is exceeded? Ie when overloaded or due to a short?
2) If so, could the leak cause this? Would a leak actually cause a multi-amp short?
3) Any other thoughts?
I will tell him to turn off every appliance in the kitchen the next time it trips and then see if a 'spark' still occurs.
As far as I know, there's no visible signs of the leak in the kitchen, and certainly not at floor/worktop level where the sockets are positioned. He says the ceiling lights in the rec room are still working!
(PS, the CU was replaced a couple of years back. I'm surprised to see it has no RCD. Is this unusual?)
Many thanks for any guidance.
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