Induction Hob and Fan Oven wiring

[jonathanhague]

Hi all,

New poster to the forum but have learned lots on this site for various DIY tasks over the past 12 months or so.

I've seen other similar posts regarding my query and also I note the Part P requirements (which I have a question about below).

- I am removing an electric oven and gas hob from the kitchen of a new house we have purchased (Gas safe engineer will have to do hob) and replacing with a new fan oven and induction hob. The current wiring set up is as follows - 32a MCB to cooker switch with additional socket. When the switch is on, the oven switches on. There is also a plug socket underneath the counter which is fed from the switch unit and only live when the main oven switch is on - this currently only supplies hob ignition.

- The new hob is 7.4 kw max. It requires 32A MCB.
- The new oven is 2.3kw max and states it requires a minimum 13a fuse.

I do not need the socket on the cooker switch unit. Is it possible and most importantly safe, to run the new hob from the existing oven switch (6mm cable?) and the oven from the plug socket?

It does however state that BOTH oven and hob need to be hard wired so I am unsure of the oven.

Also, does this fall outside of part p and will I require a certified spark to do the work if, I can wire up from the existing circuit. Thanks in advance and I hope to get some positive responses.

Jon

 

[rogerdygas]

Your mcb is too.small for the load and if you do have 6mm cable this would only take the load if it was a shortish run and clipped to the walls surface and not in any walls or between floors.

You could run the hob of the 32 amp circuit and the oven of the ring final through a fused connection unit in order to have it hardwired and fused as per instructions

Under the part p ammendments you don't have to report this job.

 

[rogerdygas]

Duplicate

 

[jonathanhague]

Thanks Rogerdygas,

That makes perfect sense. The plug socket underneath the counter which is running from the Control Switch (literally looks like a spur) - is this normal practice? Personally I would have thought that this would be potentially dangerous as that socket could be used by someone for another high drain appliance - tumble dryer for example). I would imagine that it being just for the hob ignition would be 'ok' given how little current its drawing.

I'm thinking that I might just get an electrician in anyway, just to have a look at some other sockets - it's a 20+ year old extension - and to be honest, it does look like the old dear had some cowboys do a number of jobs on the house!

Thanks for reply.

 

[rogerdygas]

The hob and cooker will need to be on two different circuits so the 32a mcb isn't overloaded.

 

[EFLImpudence]

No they won't.

A 32A cooker circuit is good for up to 15kW.

Do this -

Untitled

• EFLImpudence
• 28 Jan 2011
• 2

It's an old diagram so ignore the 10mm² marking.
6mm² will be fine if that's what you have.

 

[Taylortwocities]

Agree. Our gas friend has forgotten about diversity.

Per EFLI's picture. If the oven requires a 13amp fuse, then put a 13A socket on the feed to the oven and plug in!

 

[EFLImpudence]

It does however state that BOTH oven and hob need to be hard wired so I am unsure of the oven.

 

[jonathanhague]

Thanks all - pretty much what I had in mind. 1st thing's 1st, I wanted to make sure it is safe - then assuming it would be safe, is it notifiable:

Minor works

The Building Regulations allow certain works (known as non-notifiable or minor work) to be carried out without having to notify building control or using a registered electrician. Such work includes:

Replacing any electrical fitting (for example, socket outlets, light fittings, control switches)
Adding a fused spur (which is a socket that has a fuse and a switch that is connected to an appliance eg, heater) to an existing circuit (but not in a kitchen, bathroom or outdoors)
Any repair or maintenance work
Installing or upgrading main or supplementary equipotential bonding
Installing cabling at extra low voltage for signalling, cabling or communication purposes (for example, telephone cabling, cabling for fire alarm or burglar alarm systems, or heating control systems).


The above suggests that I'd need to comply and I can contact local planing if necessary. Other part of me is thinking however that I am only making a slight amendment to what is already there - the connection to hob is already present. Connection to the socket is also there already - I would just be changing this for an alternative.

As the oven instructions suggest hard wiring, in place of the 13a socket, I assume that I can just have a 13a FCU instead and use 2.5mm heat resistant flex to the oven?

I know some peeps come in for criticism mucking around with stuff they are not competent with but if it's not something I can do myself then at least I will know what I'm talking about if I get a spark to wire up and sign off

 

[EFLImpudence]

is it notifiable:

No.

Minor works

Yes.

The Building Regulations allow certain works (known as non-notifiable or minor work) to be carried out without having to notify building control or using a registered electrician. Such work includes:

Replacing any electrical fitting (for example, socket outlets, light fittings, control switches)
Adding a fused spur (which is a socket that has a fuse and a switch that is connected to an appliance eg, heater) to an existing circuit (but not in a kitchen, bathroom or outdoors)
Any repair or maintenance work
Installing or upgrading main or supplementary equipotential bonding
Installing cabling at extra low voltage for signalling, cabling or communication purposes (for example, telephone cabling, cabling for fire alarm or burglar alarm systems, or heating control systems).


The above suggests that I'd need to comply and I can contact local planing if necessary. Other part of me is thinking however that I am only making a slight amendment to what is already there - the connection to hob is already present. Connection to the socket is also there already - I would just be changing this for an alternative.

All changed.
All that is notifiable now are -
New Circuits, New Consumer Units and work within the zones of special locations (bathrooms etc.)

However, ALL work must comply with Part P and be tested.

As the oven instructions suggest hard wiring, in place of the 13a socket, I assume that I can just have a 13a FCU instead and use 2.5mm heat resistant flex to the oven?

Yes. 1.5mm² would do for 13A power circuit.

I know some peeps come in for criticism mucking around with stuff they are not competent with but if it's not something I can do myself then at least I will know what I'm talking about if I get a spark to wire up and sign off

Ok.

Just to point out that being 'notifiable' is nothing to do with whether the work is 'minor work' or not.
The two are not related.