Kitchen has no CCU - help required

Cnamh_Apart

Hi there,

Total noob (first post) so please forgive me if I make a balls of it.

Moving into house and at present kitchen has ageing gas cooker. I've no interest in it and will be ordering replacement hob and oven or freestanding equivalent in short order.

Problem is I can't see any sign of a CCU. The power to the gas hob is on one one of apparently two kitchen socket ring circuits (there are two 20A breakers at the CU) - and although there is a 35A breaker installed in one of the fuseways, I don't really know how to trace it to where it goes. Well I could open the CU and that, but dropping a post on here seems a bit more sensible.

Anyway I thought someone might know the answer to a few questions:

1> Can I install a new CCU myself or is it obligatory to get a registered sparks for this?

2> Does it make sense to install a 45A breaker coupled with 6mil wiring if I want to future-proof? I might want to upgrade to range or multiple cookers at a later date...

3> Is there a need for double-pole breaker as well?

I apologise if my questions are idiotic in any way but I've done my beat to research this as far as possible. FWIW I'm an electronic engineer by dint of University but that about only qualifies me to calculate load. I've no prior exposure to domestic wiring.

Thanks in advance

mikeyjames9

1.. new cooker circuit...you would need a REC for that

2... 6sq/32amp is normally adequate if you take into account diversity

anything else ,you may need to increase cable size too



3...double pole breakers or RCDs ...NO


if you can't find the cooker switch or it's not there you'll prob need a REC

Cnamh_Apart

Thanks Mikeyjames ,

Don't suppose you or anyone else might have a ballpark on the cost of running a new circuit?

Does the cable gauge have a bearing?

There's more than one path the REC might take but by my reckoning the shortest path would be 12 metres approximately.

Also if there are any RECs on here that might be interested in the work feel free to PM me. The house is in Dublin South City...

Cnamh_Apart

A wee bump, just in case someone might still want to offer some guidance on cost...

mikeyjames9

prob in the region of 250 inc. materials for a REC ,south-dublin maybe 300 or so??

you may be in a position to supply materials but would need to consult a REC on cable route and whether it's going to be flush/surface on all/part the route

http://www.meteorelectrical.com/cables-accessories_twin-earth-6242y-cable_6-0mm-twin-earth-blue-brown-basec-cuttings.html

also you would need to decide decide if you need a bigger cable or circuit(and if the installation is suitable for this)-the 6sq normally suffices for standard cooker units

Cnamh_Apart

Thanks once again Mikeyjames, I really appreciate it. Nobody pm'ed me so I'll just call around a bit I guess.

Cnamh_Apart

So this has not turned out well. About a fortnight ago I had a local REC come around to examine the setup here and hopefully gimme a quote for running in a new cooker circuit.

While we were chatting about it I mentioned that I was going for a gas hob/leccy oven and he stopped me there. Gas hob? Sure then you don't need me at all.

He went on to outlying how the hob is the real power draw and not the oven at all and advised I should be grand plugging in the oven to the sockets ring.

I was chuffed. Fair play to you my good man - you could have gouged me and you didn't. You sir are one of the good ones.

Here I am two weeks on, with a double oven on my kitchen floor and on the ratings label on the back I see that the main oven is rated 2kW and so's the top oven. Even setting aside the scenario where I'm using both ovens (Xmas turkey blah blah) - at rated max power, the fan oven could be pulling up to 8.33 Amps is that correct? If I turn on a kettle or the washing machine (both are on same ring, protected by 20 breaker at the CU) am I gonna trip it out?

Is it even safe?

Also both ovens at rated Max would exceed 13A fuse in plug no? Will I need special heat-protected cable or plug?

Hoping one of you will back up my REC and say something like: "don't worry, in practice the main oven won't ever reach the max power draw - you'll be grand..." but I don't really believe it as I'm typing that.

Confused and worried, a little advice would be really appreciated.

DublinDilbert

Cnamh_Apart wrote: »

So this has not turned out well. About a fortnight ago I had a local REC come around to examine the setup here and hopefully gimme a quote for running in a new cooker circuit.

While we were chatting about it I mentioned that I was going for a gas hob/leccy oven and he stopped me there. Gas hob? Sure then you don't need me at all.

He went on to outlying how the hob is the real power draw and not the oven at all and advised I should be grand plugging in the oven to the sockets ring.

I was chuffed. Fair play to you my good man - you could have gouged me and you didn't. You sir are one of the good ones.

No massive issue here, just get him back and say you want a separate circuit for the Oven. If its only 2KW, he could run some 2.5 T&E from the board and put a 20A breaker on it.

Cnamh_Apart

Well thanks for that. May I politely enquire what T&E is? Am I right to think he needs to hook up to the bottom busbar on the CU? There's already a 35A breaker there...

frankxxxx

if it's the double oven there's probably no diversity on the 4kw load...that's about 18amps

it may run off a 2.5 t+e and a 20amp DP switch

depends if there's any reduction factors

Tow

From the OP's original post:

The power to the gas hob is on one one of apparently two kitchen socket ring circuits (there are two 20A breakers at the CU)

Cnamh_Apart

You guys mean twin and earth right? I'd never heard of it before. What's the merit in not insulating the CPC wire? All the cables I've ever put a plug on have an insulated earth, surely it's not to save on material cost for the insulator sheath?

frankxxxx

do you have an actual double oven with 2 compartments(2 doors)

or just a single oven (1 door)with grill and oven elements

the single type rated for ~2kw could possibly be connected to a suitable spur ,the first type would need a dedicated circuit

maybe post the model or the rating

Cnamh_Apart

Yeah I've a double oven.

"on the ratings label on the back I see that the main oven is rated 2kW and so's the top oven."

So there are two ovens each rated at 2kW. But in fairness the top oven is unlikely to see usage at same time. If main oven draws 8A, kettle bout 2A, washing machine is 10A-rated so that means I can't use these items simultaneously right?

I though a cooker circuit was necessary from the start, wish I'd followed my instincts.

bassey

Cnamh_Apart wrote: »

You guys mean twin and earth right? I'd never heard of it before. What's the merit in not insulating the CPC wire? All the cables I've ever put a plug on have an insulated earth, surely it's not to save on material cost for the insulator sheath?

Just on this, the cpc is insulated on either side by the phase and neutral conductors, when it's terminated at a socket the cpc is sleeved.