New 13amp oven installation question?

LostInLM

Need to replace existing faulty oven with the following new model : BOSCH HBA13R150B
According to the spec its rated 2900W / 13A.
The oven is supplied with an ~2.5mm flex, no plug.

When I lifted out the old oven the cable from the isolation switch is connected directly into the back of the it.
Also the ignition wire for the gas hob is tapped into the back of the oven directly from the 6mm cable.
As this is a much smaller flex (<1mm) I severely doubt if this was done correctly day 1.

My OH is putting pressure on to get oven back up and running, or kids go hungry, so need to get new oven in place :-)

My questions are :

• New oven - as this is rated 13 amp should the flex for new oven be connected to exiting cable / 45amp isolation switch via a 13amp fused connection, or is it acceptable to just join directly into existing cable via a CCU?

• Hob ignition - I assume that this should go through a fuse to step down to protect the much smaller flex.  Should this have a separate fused connection, or would it be acceptable to connect both hob and new over via a single 13 amp fused connection?

What would be best practice in this scenario?

Thanks.

LostInLM

Was thinking some more about this setup and wondering is simplest solution to place a double socket on end of 6mm cable under the counter with one 13amp fused plug for oven and another 3amp fused plug for hob ignition? Existing cooker switch will provide isolation for both. Or am I completely over thinking this?

Tuco88

A Spur outlet could be used that way its a fixed appliance.

If you decide to place a socket it must be protected by an RCD or a non standard "T Bar " like socket.

You could place the circuit on the RCD at the consumer unit or get a "SRCD" socket with built in RCD.

You will have a 32amp Protective Device protecting a 6mm^2 cable which is perfectly acceptable but a 13amp Socket on the end sounds a bit wrong.

LostInLM

Thanks for the feedback Tuco88.

Not sure if an RCD socket would be practical in this scenario as the plugs would be connected behind the oven and not easy to access. Any nuisance trips would involve removing the oven to reset. Also impossible to test without removing the oven.

Existing 32amp oven circuit is not on RCD. What would be the reason for needing in the new arrangement? In this scenario I would not imagine that somebody would easily plug out the oven / hob ignition to put in a portable appliance. For all intent and purpose it's a fixed appliance on the existing cooker radial.

In existing arrangement the hob flex was just connected straight into the 6mm circuit without rcd or fuse protection, so anything else would be an improvement imho.

Tuco88

If you placed a socket without RCD protection. So you decided to move the next owner might decide to redo the kitchen and use that socket for another appliance unknown of the risk.

Your existing oven is considered a fixed appliance (No plug or Socket) so RCD protection is exempt.

Seeing you have no later access your best option is go with a spur outlet. Just remember you will have the same issue if 13amp fuse goes.

But yes it would be much better than the current set up.

LostInLM

Got it. Scrap the double socket idea so :-)

FCU outlet is probably the best way to go.
Or 2, first with 13amp fuse for oven and second with 3amp fuse for the hob ignition. Might be fun trying to get the 6mm cable into the FCU though!

Taking a spur off existing socket radials is not really an option without major work and OH might not be impressed with chasing through tiles in kitchen:D

Tuco88

When I mean spur I mean spur outlet/FCU rather than a spur from a ring circuit. Sorry its just to make it more confusing.

Two outlets would be ideal.

You should manage to get the 6mm^2 in alright, the problem is trying to loop to another &#55357;&#56833;.

Risteard81

Tuco88 wrote: »

but a 13amp Socket on the end sounds a bit wrong.

Why? It's no different to what you would have with a ring final circuit.

Tuco88

Risteard81 wrote: »

Why? It's no different to what you would have with a ring final circuit.

Ya I stated its fine just sounds uncommon to the norm.
Its not normal to see a radial 13amp Socket supplied from a 32amp Mcb is it?

Risteard81

Tuco88 wrote: »

Risteard81 wrote: »

Why? It's no different to what you would have with a ring final circuit.

Ya I stated its fine just sounds uncommon to the norm.
Its not normal to see a radial 13amp Socket supplied from a 32amp Mcb is it?

It's excessive for the load a single socket outlet can carry, but certainly adequately protected. As you point out, however, if a socket outlet is fitted then 30mA RCD protection is mandatory.

Tuco88

Risteard81 wrote: »

It's excessive for the load a single socket outlet can carry, but certainly adequately protected. As you point out, however, if a socket outlet is fitted then 30mA RCD protection is mandatory.

Yes as I stated in post 3.

I think the situation of a cooker being replaced by a seprate hob and oven has shown alot of DIYers handy work.

tweek84

The norm is Mcbs are sized to protect the cable, cables are sized due to the load