June 13, 2017 
Trips the circuit when power is switched on at wall, before even turing oven on, no clock light. etc. Cooker is second hand but has been working for a year since electrician wired it in. Any help gratefully received.
cat forster
I will try and help with this problem Kenwood CK230 cooker
Good afternoon, this will most probably be one of the elements, there may be a thermostat slightly open letting power through to the element and the element has got leakage to Earth above the 30 milliamps on the fuse boards. If the resistance to Earth is greater than this it will cause your RCD on your fuse board to blow.
I suggest you either get someone with a mega (insulation tester) to find which element is causing the problem or you could individually disconnect each element and try to isolate which one it is, I have added a video below to show you how to test elements and also listed the elements that fit your model of appliance Kenwood CK230, I hope this helps you.
If you need any further assistance please feel free to contact me. all the best Paul.
Paul Charmbury
Appliances Engineer
