Question for sparkies - RCD tripped

[Theremin]

Was working away on the computer last night, and power to the house went off, but all the lights stayed on. Had a look at the switchboard and the RCD had tripped. So I turned off all power circuits, turned the RCD back on, then started turning back on the power circuits and all went ok until I turn the kitchen circuit on, then the RCD trips again. I turned off all appliances in the kitchen, still no good. It turns out the fridge/freezer is on a different circuit, so I figured I'll worry about it in the morning. Then this morning, I was able to turn everything on, including the kitchen circuit.

So what do you think? Could it be water that has shorted something, and which has dried up overnight? It wasn't raining last night.

If I get a sparky out, are they going to be able to work out what went wrong, now that everything seems to be working fine again? Or should I just wait and see whether it does it again?

[NCArcher]

Turning off the appliances is not enough. You need to unplug them.
Usually something with a heating element. Heats up, expands allows moisture in trips the RCD. By morning it is cool and has shrunk back to a tight seal. Or something along those lines.
Your sparkie will not be able to locate a fault that doesn't exist. He will be able to test every appliance and may find the one that caused the problem but i wouldn't want to pay for that.
Wait and see what happens.

[tricky4000]

Some animal has chewed through the wiring? Some creature has made contact with the back of a power point maybe? That's a tough one...and very annoying I bet.