Possible dodgy oven wiring discovered

[baldelectrician]

Have you checked the details of the electrician / company on the NICEIC website?

You can complain to the NICEIC about the work if the contractor is NIEIC registered.

 

[Midwest]

Have you checked the details of the electrician / company on the NICEIC website?

You can complain to the NICEIC about the work if the contractor is NIEIC registered.

I think the OP has, and the NIC responce was the norm.

 

[FatAlan]

Easiest solution is just to get them to replace the oven with one that runs off a 13amp socket. Other than that, it’s a dispute over whether the rewire spec should have had a dedicated cooker circuit and you’d like to think that there was one there originally.

 

[James2019]

I think the OP has, and the NIC responce was the norm.

I have the details of the electrician and his company name from the report, and they match up with whats on the NIC website. However to follow their resolution process, you must go back to the installer first to raise your concerns and allow them a chance to resolve.

I will definitely send them a complaint when I am completely done with any more visits or trying to squeeze any compensation out for this (such as oven replacement). I do not suppose they will do much, however if there is any chance this will help stop this happening to anyone else then that will be good.

 

[James2019]

Easiest solution is just to get them to replace the oven with one that runs off a 13amp socket. Other than that, it’s a dispute over whether the rewire spec should have had a dedicated cooker circuit and you’d like to think that there was one there originally.

I think you're right there. Wife quite adamant about keeping the oven, however I think it will be preferable to get an oven that runs off a 13A socket rather than run a new circuit since we've finished plastering, redecoration and moved in last week!

In the old wiring for the kitchen circuit I believe 6mm cable was used and a BS3036 30A rated fuse. They had a gas oven/gas hob. The old wiring (pre-rewire) had 22 C2s when I had an EICR conducted (I used someone else for the EICR when buying the house). I think that was mainly due to the age of the install/changing norms.

 

[telectrix]

if that 6mm cable is still in situ, maybe it could be re-used to provide a dedicated cooker circuit.

 

[FatAlan]

Did my kitchen a year or so back. Although I put in a dedicated feed for ovens, both the oven an microwave combi are on standard 13amp plugs. Loads of good options out there .. you just need to sell it to the Mrs ? Appreciate that it’s a compromise and the ‘builder/spark’ has let you down ?

 

[Midwest]

Did my kitchen a year or so back. Although I put in a dedicated feed for ovens, both the oven an microwave combi are on standard 13amp plugs. Loads of good options out there .. you just need to sell it to the Mrs ? Appreciate that it’s a compromise and the ‘builder/spark’ has let you down ?

Thing is 'we' all know and expect an 'oven' to be on its own circuit, just like a shower.

 

[Lucien Nunes]

We recently had a thread, perhaps someone else can find it (I don't have time now to trawl) about connecting a load over 13A to an RFC. Careful study of the regs seemed to indicate that a B16 MCB is permissible in place of a 13A fuse to BS1362. That would allow the existing oven to be connected to a 32A circuit.

If that is the case, notwithstanding the recommendation for all large loads to be supplied independently of a general socket-outlet RFC, I do not think there is much to gain by changing the oven to one with a lower maximum current. The power used during cooking under thermostatic control depends on the heat loss from the oven, not the rating of the elements. There are some subtleties here that I won't go into now but suffice to say the effect of a slightly lower element rating on the usability of the circuit for other loads isn't worth the cost and effort of changing the oven.

 

[Lucien Nunes]

See this post:
16A OCPD acceptable on 32A RFC

I would consider that much more satisfactory than fusing the circuits down. The present situation with an undersized MCB that does not trip in practice, is still non-compliant if the design load exceeds its rating. This leads to the undesirable situation of the MCB having to withstand regular small non-tripping overloads.

 

[brianmoooore]

16A is the maximum load of the oven. I would be surprised if it wasn't designed to be fused at 32A, as it would be if connected to a standard cooker circuit.
What do the manufacturer's instructions say on the subject.

 

[FatAlan]

Going back to the OP. Does still beg the question why the current oven isn’t working correctly bearing in mind no OCPD devices have tripped. I take it that it’s not one of those hardwire connections with a multiphase option that has been wired incorrectly meaning only half the elements work?

 

[Lucien Nunes]

Post #1 did imply that there was an intermittent contact / connection at the socket, as the socket tester used by the man from Bosch at first indicated a fault that disappeared after they plugged things in and out.

 

[Lucien Nunes]

I would be surprised if it wasn't designed to be fused at 32A

Good idea to check. I have definitely seen two ovens of 3.6kW / 16A rating that specified maximum 20A fuse or MCB but that is not to say this one requires it. In any case, as per my post above, it seems in order to fuse down to 16A with a 60898 from an RFC.

 

[James2019]

See this post:
16A OCPD acceptable on 32A RFC

I would consider that much more satisfactory than fusing the circuits down. The present situation with an undersized MCB that does not trip in practice, is still non-compliant if the design load exceeds its rating. This leads to the undesirable situation of the MCB having to withstand regular small non-tripping overloads.

Thanks for taking the time to dig that up and offer the suggestion. This does sound promising.