Electrical problem - help!

[CobolMan]

We've been in our house for 7.5 years now, ever since it was built and we've had various problems with the electrics in the kitchen, mostly related to the oven triggering the RCD, generally once a year and usually when we've got friends round for a meal

The consumer unit is in the garage and the immersion, cooker and both downstairs and upstairs circuits are protected by the RCD. My next door neighbour has the exact same style of house but their immersion is not protected by the RCD. We never have our immersion switched on (there's a switch in the kitchen for that). The rating of the RCD is 80A.

In the past we've had the RCD trigger when the oven and all 4 rings on the ceramic hob are in use and I've put the kettle on. We've also had the RCD trigger when the fan element in the oven has failed.

However, tonight's was a new fail - the oven wasn't on, only two hobs had been used (and had been switched off for about 10 minutes) and the kettle wasn't on. The RCD triggered and when I went into the garage to reset it, the only way I could restore power to our downstairs and upstairs sockets was to isolate the cooker circuit - not ideal.

We have had an electrician round in the past and they haven't been overly impressed by the quality of work but they can't find anything obviously wrong. I'm going to contact the builder tomorrow as the house is still covered by the NHBC warranty but I was hoping there may be some PH electricians who could shed light (pardon the pun) on what may be going on.

Thanks in advance.

[Simpo Two]

My old cooker used to do that - it would be fine for a while, but then when the thermostat cut back in it would plunge the house into darkness.

As the cooker was pretty crap anyway, I was happy to swap it for the surplus Neff my uncle was throwing out, and that fixed the problem.

[Ganglandboss]

CobolMan said:

the only way I could restore power to our downstairs and upstairs sockets was to isolate the cooker circuit - not ideal.

Are you isolating it at the breaker or the cooker switch? If you switch the cooker off at the local switch and it still trips, the fault is most likely to be the wiring between the consumer unit and the cooker. If the RCD resets okay when the local switch is off, the fault will most likely be with the cooker.

[CobolMan]

Ganglandboss said:

Are you isolating it at the breaker or the cooker switch? If you switch the cooker off at the local switch and it still trips, the fault is most likely to be the wiring between the consumer unit and the cooker. If the RCD resets okay when the local switch is off, the fault will most likely be with the cooker.

It was initially isolated at the RCD only. Switching off the cooker at the local switch let me reset the RCD circuit. Turning the cooker on again at the local switch didn't trip the RCD this time - most odd. In the past, turning it on at the local switch has resulted in the RCD tripping.....

I'll get an electrician in to have a good look at it.