Kitchen wiring woes

[DrDigestive]

Hi, I am not an electrician so please be gentle and I am fully aware I have been stupid trying to take on this work myself but I got let down by an electrician so ended up doing it myself as a plasterer was coming the day after.

We just moved into a new house and the kitchen wiring looked shoddy at best, a lot of sockets needed moving etc. Even some exposed wires behind the kitchen cabinets (eek!) We have bought a 4.9kw double oven, a gas hob, and an extractor hood. There was an existing 10mm cable leading to an oven connection with a socket above it, I have wired that into a 20amp isolator switch, then from that switch there is a small length of 2.5mm wire going to a 13amp isolator switch. From the 20amp isolator there is a 2.5mm T&E cable which will eventually be installed into the oven. From the 13 amp isolator I am planning on wiring the extractor hood and the gas hob ignition over 2.5mm T&E.

Is any of this safe whatsoever? I am planning on getting an electrician in to test it all but I am mainly worried about the 2.5mm wire feeding the 13amp isolator from the 20amp one (the 10mm feed cable and 2.5mm bridge cable are in the "in" connectors, and the cooker connector is in the "out" connectors on the isolator)

And again, I know that I am ridiculous for trying to do this myself! I am also unsure if its actually 10mm cable. Its definitely alot fatter than the 2.5 I have, like twice the width. Thanks in advance! I've attached a pic for your amusement.

 

[Taylortwocities]

I've only had a quick glance.
1. Your wiring does not seem right. It should comply with wiring in safe zones. See //www.diynot.com/wiki/Electrics:walls
2. Your 10mm cable, is that the cooker circuit? What is the value of the fuse/MCB in the consumer unit for that circuit. I expect is is probably 40amp. 2.5mm² cable will melt if you put 40amp through it. Ditto your 20amp switch will destroy itself.
Your oven needs to connect to the existing circuit where the 10mm² cable is. Not through ever decreasing small pieces of cable that are not big enough.
This needs a re-think. And I really suspect you need to find an electrician to help you.

Postpone the plasterer.

 

[DrDigestive]

I've only had a quick glance.
1. Your wiring does not seem right. It should comply with wiring in safe zones. See //www.diynot.com/wiki/Electrics:walls
2. Your 10mm cable, is that the cooker circuit? What is the value of the fuse/MCB in the consumer unit for that circuit. I expect is is probably 40amp. 2.5mm² cable will melt if you put 40amp through it. Ditto your 20amp switch will destroy itself.
Your oven needs to connect to the existing circuit where the 10mm² cable is. Not through ever decreasing small pieces of cable that are not big enough.
This needs a re-think. And I really suspect you need to find an electrician to help you.

Postpone the plasterer.

Just cancelled the plasterer. I knew what the right answer was but I just want it done. Thanks for bringing me back to sanity!

 

[OwainDIYer]

From the 20amp isolator there is a 2.5mm T&E cable which will eventually be installed into the oven.

That should be a 6 mm cable and a 30 amp isolator for the double oven. 20A is a bit borderline ... yes I know there is diversity but you're only putting this in once so do it right.

As said the cables must be in safe zones and I would do vertical cables only, with all the horizontal sections near floor level in trunking. Chase in 20 mm conduit into the walls for the verticals as it allows cables to be withdrawn or replaced in the future of cooker/fan locations change.

 

[PrenticeBoyofDerry]

Hi, I am not an electrician...
I know that I am ridiculous for trying to do this myself!

Not the word I would have chosen!
Get an electrician in my friend!

 

[DrDigestive]

From the 20amp isolator there is a 2.5mm T&E cable which will eventually be installed into the oven.

That should be a 6 mm cable and a 30 amp isolator for the double oven. 20A is a bit borderline ... yes I know there is diversity but you're only putting this in once so do it right.

As said the cables must be in safe zones and I would do vertical cables only, with all the horizontal sections near floor level in trunking. Chase in 20 mm conduit into the walls for the verticals as it allows cables to be withdrawn or replaced in the future of cooker/fan locations change.

Not a bad idea. I think I'm getting a sparky in, I've managed to get away with what limited electrical knowledge I have so far but this is outside of my comfort zone. Plasterer plastered the kitchen last night- so I'll let the electrician ruin it next Wednesday when my appliances turn up that whole area is pretty much going to be tiles or cupboards anyway so its no biggie