Electric supply to a cooker hood and a GAS hob.

[chunkymonkey2778]

Hi all, DIY isn't really my specialist subject so just thought I'd ask before I went ahead and did it.

I'm changing my kitchen but the worktops are second hand. The hob is roughly 50mm further left than my stand alone used to be, and what with having a splashback and a cooker hood I'm having to lose an electrical switch that controls the original built in ceiling extractor.

Around 100mm to the left is another electrical switch that controlled some sort of weird heater matrix thing that broke years ago. That switch will be staying but I want it to control the cooker hood instead.

The right hand switch that's going is the one with the feed to it, then it's spurred to the left hand switch.

Can I use chockblock or a junction box to connect the feed to the spur, bury it behind the splashback/tiles then use the wiring for the original extractor to supply the new cooker hood?

Apologies if I've gone about describing it the long way round......

 

[winston1]

No, because the feed to the switch you are losing will no longer be in a safe zone.

 

[conny]

If that grey cable coming from the left and going to the right hand switch is the feed to the right hand switch then you should be able to connect it to the left switch and, possibly, do away with any form of connection block.
As I'm not an electrician wait until one does come along and give you qualified advice.
Be warned they will probably ask various questions which you may not be able to answer.

 

[chunkymonkey2778]

Winston, what's a safe zone please? And it's not safe because of the heat from the cooker or something?

It'll be inside the original metal housing and after doing a bit more research was looking at using click flow clips or similar, which would then be half behind a tile and half behind a splashback?

Conny no the feed comes from above the right hand socket and spurs into the left, so I just want to basically extend that feed into the left hand socket and then seal it all off and tile/splashback it in.

 

[chunkymonkey2778]

Reading up on safe zones then if my hob has only moved 50mm to the left from when the original kitchen was fitted (house built in 2003) then unless the regulations changed afterwards then it was illegal when fitted? Or has moving the hob 50mm to the left encroached into the hot/safe zone?

 

[chunkymonkey2778]

Worktop will be 50mm left from where it is now.

 

[winston1]

Winston, what's a safe zone please?

In general cables in the walls must be horizontally or vertically in line with an accessory, though there are variations near corners or ceilings. These are the safe zones. The switch you intend to remove appears to have wires coming down to it. If you remove it those wires will no longer be in a safe zone.

 

[Taylortwocities]

Winston, what's a safe zone please? And it's not safe because of the heat from the cooker or something?

"Safe zone" is a curious term as, in my mind it is an unsafe zone.
Basically the zone are the routes where cables are allowed to be installed. Basically these are in a line horizontally or vertically from a socket, switch or other wiring accessory. Plus some other areas near corners and ceilings.
It is described here https://www.diynot.com/wiki/Electrics:walls

 

[chunkymonkey2778]

Ok thanks to you both, I'm assuming if I'm leaving the earthed metal box in the wall still and using click flows secured inside the box then that wouldn't still make it a safe zone, it has to have the socket front there to make it so?

Obviously not disputing what anyone's saying but seems odd it's not a safe repair if it'll be behind a splashback and cooker hood.

So would my only option be to trace the feed from the right hand socket back up the conduit and then feed it back down the conduit to the left hand socket that the feed to the electric fan goes up?

 

[Taylortwocities]

For clarification, the “safe” zone is concerned with wiring routes and nothing to do with heat/closeness to hobs/sinks etc. There is a guidance distance of 300mm. Also accessories must be suitable for the environment.

Ok thanks to you both, I'm assuming if I'm leaving the earthed metal box in the wall still and using click flows secured inside the box then that wouldn't still make it a safe zone, it has to have the socket front there to make it so?

I don’t think you mean ClickFlows. They are large connectors. Wago connectors might be more suitable. You could make the joint in the box and put a blank plate over it to denote the presence of cables.

Obviously not disputing what anyone's saying but seems odd it's not a safe repair if it'll be behind a splashback and cooker hood.

A future owner of the property will not know the cable is there and could be electrocuted should they drill into the areas fit a knife rack etc. It has happened. STORY

So would my only option be to trace the feed from the right hand socket back up the conduit and then feed it back down the conduit to the left hand socket that the feed to the electric fan goes up?

Yes. In fact I can see a contravention in the existing wiring. The cable that comes down the left hand conduit is routed diagonally to the right hand FCU. That is outside the zone, so needs sorting in any event.

 

[boringoldcodger]

Obviously not disputing what anyone's saying but seems odd it's not a safe repair if it'll be behind a splashback and cooker hood.

But TTC is pretty accurate when he says:

"Safe zone" is a curious term as, in my mind it is an unsafe zone.

The "safe zones" show where you must be careful 'cos they might contain electric cables and, as others have said, you show where these zones are by having a switch or socket or one of a few other things in the wall.

Living down to my moniker, arguably a "safe zone" is one where it is safe to put an electric cable 'cos there's an indication that you shouldn't put anything else there.

 

[chunkymonkey2778]

Hi again all, thanks for everyone's help, yes I'm getting confused with safe zones and hot zones by the look of things, so now that's sorted I'll get to work.

One other question, if the feed wire that needs to be rerouted turns out to be too short to reach the left hand box what's an acceptable repair to lengthen it, bearing in mind it'll be then behind the protective sleeve again and filled back over, most probably also behind a cabinet?

 

[winston1]

Best to replace the whole length of cable back to where it comes from.

 

[chunkymonkey2778]

Ok. Is that likely to run all the way back to the fuseboard if it's the main feed for the downstairs sockets or will there be a join in each room or something?

If so could I terminate that live feed inside a wall somewhere? I have a cooker and 3 pin socket the other side of the hob that I could lose a socket for and run the feed from there instead?

 

[Taylortwocities]

Not likely to go all the way back to the fuse board. Looking at the wiring in the picture there’s no guarantee what had been done by previous kitchen fitters/handymen.

A junction buried in the wall is never a good plan. Even then it must be a MAINTENANCE FREE joint.

A bit of detective work will discover the wiring routes.