Kiln problems and RCD circuits

I've just had the scare of my working life! Last weekend I made some repairs to the firebricks in my electric top-loading kiln. The fire-cement was quite wet, but I 've done these repairs before.... however not with a new RCD circuit and trip switch fitted onto the house.

The problem started on Sunday- I dried the cement out on Saturday- or so I thought- by placing an electric heater inside the kiln. Sunday- the kiln clicked once- then tripped off all the power. And kept doing it- OVER AND OVER AGAIN! Disaster!

I got Essex Kilns in, they asked if the fire cement was still wet. No I replied it's all dry. And yes it was touch dry- or so it seemed.

Out they come- "Nothing wrong with the kiln mate-there's a small leak of electricity onto the casing- makes it trip. Up the millampage from 30-100 that'll sort it and get it put on a separate RCD circuit.Bob's yer uncle." Well with the prospect of hundreds of pounds of work looming, it made me shudder. And the fact that my reliable old sparky does a runner every time I tried calling him. Can you find a decent sparky these days anywhere?

Luckily top East Anglian potter-John Masterson- recommended NRG- a company based in East Anglia. So I thought at least they know how to deal with potters...Lo and behold a chap phones me up- convinces me that putting in a new RCD is a waste of time and money and that the fire cement is still not dry. He was right. There's a lesson in here somewhere....

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