Cooker tripping rcd

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Hi, I've recently install my smeg suk92mfx which has been stored in the garage for a few years. It's a range cooker. On turn on of the main oven on any setting, including the oven light only, then turning the temp Control (far left control) , 10-15 secs later it trips the rcd. The secondary oven works OK on all settings. I've replaced all the elements at a cost of over 100 quid (using friendly ebay). Any suggestions now? I would like to look at the main switches on the panel, but there seems no way to remove them. Anyone know how to? Any other things to try?
Thanks in advance,
Cooker link
https://www.amazon.co.uk/Smeg-Range...ocphy=9045283&hvtargid=pla-763297259997&psc=1
 
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It may be damp, somewhere.
Usually it’s the mineral insulation found the elements that soaks up some moisture. But you’ve changed those.

You will need an Insulation Resistance Tester to trace where the problem lies.
 
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It's usually damp in one of the elements, usually the oven, but you say you've renewed them all.

Unplug them all, see if it still trips, if not, plug them back in, one at a time, and see if you can trace the faulty one.

if you have a multimeter, test the resistance to earth of each element. You can do it quicker by working on the connection block (disconnected from power) and turning the elements on one at a time. If it has electronic controls, this may not work.

edit
see above, Taylor has in mind an insulation tester that works at a higher voltage and is better at finding faults. I assume you haven't got one. Better if you have.
 
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Thanks for the replies, i do have an insulation resistance tester, used on testing domestic installs. I assume this is the right thing? Goes up to 1000V. Should i just test the elements to earth or via the element ends? I didnt test the elements out of situ before install. I guess i could do this. How do i do this using the IR tester?
The odd this is that the selector switch has a light only switch, if i select this, and turn the temp knob it trips. Surely no elements are being connected at this stage? Does the temp switch usually go via a relay or pot of some sorts?
 
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It's usually damp in one of the elements, usually the oven, but you say you've renewed them all.
Could it be the insulation is damp on back of the oven? Is it OK to use without this in situ/ test?
 
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I'll take the back off today and test the elements with the insulation resistance tester. Perhaps one I bought is faulty.
Visual inspection of the back shows nothing obvious. Stripping the cooker is a bit of a no no as the hobs and side oven are in daily use. I'd like to have a plan on how to get to the main switch before I start! I had a try last time, got as far as removing all the knobs and the front panel, but the switches are behind the front chassis. There's also no access from the back. The front chassis is secured by the side chassis etc etc.
I always wondered if the Cooker has another fault as when you switch the grill off after cooking, the main fan starts up.
 
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The fan starting is not a fault it's to cool it down after use. If the side panels are covering the securing screws for the control panel you will only need to take the top screws out of the side panels & then gently pull the corners away to access the control panel screws. Looking at the pdf. I wondered if you might have a problem with the temp. probe part of item 42763 if it is possible you could try temporarily disconnecting that to see if it removes the problem.
 
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The fan starting is not a fault it's to cool it down after use. If the side panels are covering the securing screws for the control panel you will only need to take the top screws out of the side panels & then gently pull the corners away to access the control panel screws. Looking at the pdf. I wondered if you might have a problem with the temp. probe part of item 42763 if it is possible you could try temporarily disconnecting that to see if it removes the problem.
Thanks jj for the tip.
I did try removing the fp but as you said the screws under the side panel were obscuring the heads. You'd have to take the side panel off to get access to them. I didn't quite understand, are you saying there is a way to get the fp off without removing the sp?
I think the probe goes through a hole in the back and into the oven? Is this the one you mean?
 
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I would have thought the side panels would have been secured at the middle & corners of each side & that by removing the front top & perhaps front middle screws that you would be able to pull it away from the chassis & therefore the front panel enough that you can see the control panel screws that were covered by the side panel. I'm not sure where the probe physically fits you would have to trace the cable back to the temp. controller which is where you would need to disconnect it from if that is possible ( it may be moulded into the assy.) There are 2 by the look of it, item 42763 & item 44153, one for each oven I would guess but don't know which is which.
 
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Bit of an update, I checked the new elements yesterday and lo and behold one of my new elements is showing 0.06Mohm on the IR tester. Disconnected it, and it now no longer tripping. If course I now have a hassle as I got it off ebay. :( All other are showing high R in the orders of 7-12 mohm. What's a good value for new elements? I was expecting them to be in the order of 100M. I'm grounding off the chassis so perpahs the earth is no so good?
 
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There will be some small amount of moisture in the elements until they’ve been in use for a while. The results you have are ok.

Good luck with the replacement.
 
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Swapped over the new element. No tripping so far.
IR is showing 0.19M out the cooker. Obviously just enough to trip out the rcd. 240/190000 = 12ma. Perhaps there's so other leakage somewhere? Am I right in assuming that the resistance of the element would drop further once it starts to draw proper current? Ie 10A.

No obvious signs of damage on the old one. Perhaps it's damp? The new element was showing >10M. Has anyone ever tried the trick of connecting the L and N without the earth to dry the element out? Obviously this is highly dodgy I guess if you don't know what you're doing. I noticed this one came in a sealed plastic bag. The other didn't abd was packed loose.
 
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Bitof an update. Cooker still working fine. However the main fan oven ventilation element is a pattern part and doesn't heat up the oven properly. On close r inspection the smeg part is rated 2.8kw, the pattern part 2kw. Moral of the story, don't buy the pattern parts!
 
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