UKH

After the undercounter freezer question and the extractor fan question (older threads), step three of sprucing up my kitchen is the replacement of an old gas cooker. 

I am thinking of getting a combination convection/microwave oven, and a separate 2-zone induction hob. 

My kitchen does not have a separate cooker circuit, which I believe tend to be rated to 30A or 45A, and indeed I see that even the basic standard electric cookers would need this. 

However it is my understanding that if you are running at less than 3kW, a 13A standard fused plug into your standard mains should be OK. 

The ovens I am looking at all seem to be around 1000W. 

Induction hobs vary and a quick Internet search seems to show them rated by fuse rather than power; it so happens that the one I have my eye on states 12.3A

I am not going to be using these things at full whack anyway. 

Is there any reason that I should still get a cooker circuit installed? I'm not trying to cut corners or be a total cheapskate but if it is not necessary for these devices (which will actually plug into different rings), then it would be good to not bother at least for now :-/ 

Are my calculations or logic wrong? Normal microwaves, after all, are around 800-900W. My kettle and iron claim to be nearly 3kW which presumably is on the limit of a 13A fuse. 

In reply to Blue Straggler:

Do the items in question come with 13A plugs? 

There are some which do, and presumably they wouldn’t if it wasn’t ok to just plug them in.  

I think the 30A cooker circuit is from when the cooker and hob were all in one item.  

In reply to Blue Straggler:

Remember ALF and his hairdryer?

In reply to Blue Straggler:

13a circuit will be fine up to 3kw.

1000w is a third of a kettle...

In reply to Blue Straggler:

Not an expert, but IIRC if a cooker draws less than 3kW it can be plugged in, over 3kw it needs to be into a separate circuit.

If your cooker and the separate hob come with a plug then shouldn't be an issue. It sounds like the induction hob might be an issue though.

In reply to Ridge:

Cheers. It looks like all those ~1000W combi ovens are plug and play, but a lot of induction hobs, even <13A, state "electrician needed for installation" although at the sub 13A level this seems to mean little more than "plug not included" (a few do state "plug included, no electrician needed"; the one I am looking at does not state this. I am pretty happy fitting a plug!)

I've had an electrician round for a general "look see" and raised this question. Basically he said that the only real issue is power limits on the cooking devices, and given that I am not running cookers at full whack, then plug and play should do the trick.

Logically thinking....I am not purchasing things specifically to avoid putting a new circuit in (to be honest that would not be a huge job as we can put the outlet directly below where the fuse box sits) so I could probably just suck it and see....

In reply to wintertree:

Due to Straggler family snobbishness, we were discouraged from watching ITV, it was rationed on a negotiable basis, and I never pushed for ALF (nor Terrahawks, nor Jamie and His Magic Torch). So, no.

In reply to Blue Straggler:

A couple of notes...

I don't think that the plug or lack thereof is necessarily the only difference.  I don't make ovens, but in my field the safety rules for portable electronics (which have plugs) and devices for fixed installation (which don't) are different. I have no idea how or if this applies to cookers though.

For the oven at least, it will come on at full power when it is warming up, even if you're not running it at a high temperature.  Similarly with the hob, I don't know about you but if I'm cooking I often put the ring on at full power to get something boiling then turn it down.  These things don't last long but probably do count as full whack from an electrical point of view. It doesn't take long for a high current to trip a breaker or overheat a bad joint.

That said, it still sounds OK overall to me.

In reply to Jack B:

I think you make a good point! Still, like a bull in a china shop I'll get the one I want, and if it trips anything, then I'll get the electrician back in. The units that ARE "plug and play", cost more anyway and I might as well spend that money on getting a circuit put in and then I've got full versatility  

Cheers


In the past I'd have procrastinated over this for months and made do with my (surprisingly adequate for my needs) plug and play little Baby Belling unit (small oven and two electric plate hobs!) but I am really trying this year to be more pro-active about domestic aspects. 

In reply to Blue Straggler:

If you do get the electrician in you can get 2 16a for them.  That's what I've put in.  That way if one of them is a problem you can still use the other. 

In reply to Blue Straggler:

I bought one of these for a flat I was renting many years ago & although it was good as a microwave (still being used some 20  years later) it was pretty hopeless as an oven or grill. Maybe the technology has improved but worth checking.

In reply to Doug:

Thanks for the heads up. I think the technology has changed; the concept is new to me, a trusted friend (and tech nerd) recommended it and from reading up, they are pretty good. I remember my mum bought a microwave with “grill facility” around 20 years ago and never used the grill facility as it was hopeless.

In reply to Blue Straggler:

I was told by an electrician recently that in most new build houses they don't bother with installing a dedicated cooker circuit unless a range cooker is specified.

As far as other things go you should check what sort of circuit you have first (ring or radial) as the mcbs should be different. And also check that you are not plugging everything into a spur off a ring.

In reply to Blue Straggler:

Single ovens with a fan and grill will just need a 13amp plug as they are rated at less than 3kw. Please try an avoid digital ovens when they go wrong they're invariably scrap because of expensive electronics. Electronics and high heat levels are not a great combination. If the temperature indication is arouhd the knob means its an analogue control it the temperature is displayed in a separate window its digital. Any engineer will tell you that simplicity is more reliable and ovens are simple devices. I'm out of self isolation tomorrow (yippee!) and have got 3 ovens with heating problems to look at. Oh and those single ovens with slide under doors a la 'Bake Off' the doors and sliding equipment is a load of plastic.thin wire and small springs- nightmare when they break, make sure you are on a warranty scheme if you get one of those.

In reply to Blue Straggler:

We have a combination oven/microwave. It's great. It's a little small if you want to do a whole Sunday roast in it, but for cooking things that aren't too tall, you can get two shelves in comfortably. We use it as a microwave mostly because we also have a second oven. It does come in handy at Christmas time when we've got a full house of family (I wish)

As regards the circuit. If both of the items you're going to purchase come with a plug fitted, plug them in. All the sockets in your house should/will be fed by either a 16a radial or 32a ring main circuit backed up by an MCB/Fuse, so no issue with loading. One other thing to consider, is that the sparky may have to "Upgrade" other parts of your house's wiring before he can sign off the work he's done. Earthing being one, Consumer unit being another. He should inform you beforehand if extra works will be needed.

In reply to Blue Straggler:

If it comes with a 13A plug fitted, it can be plugged in (or hard wired on a fused spur) if you like.

Most ovens do.  Most hobs don't, as they are generally much higher powered than ovens (this seems odd, but as ovens can take their time to heat up and can keep the heat in it actually makes sense), though some have a degraded setting to allow such use.

In reply to Blue Straggler:

Okay; to cut a cheap plot gimmick short, get a dedicated circuit.  At some point you’ll overload the fuse in the middle of a meal and spoil it.  Just imagine it blowing whilst you’re searing diced wood pidgin breast and garlic in spitting hot butter for 90 seconds before mixing in some red berry jam.  The meat would be wrecked whilst you changed the fuse, it’s not worth the risk.

At least the ITV ban means you were spared the horrors of Grotbag and T-Bag.

In reply to arch:

OK so Straggler Mansions is at least 208 years old. The wiring is probably 40 years old but crucially it's all been working fine all the time I've been here and I am not about to start a major rewiring project. 

The fuse box is four Bakelite-and wire fuses. One "mains for most of the house". One for the lights. One 15A for most of the kitchen (weirdly seems related to the whole-house one, as when I remove the latter, everything that that kitchen fuse looks after, goes off). And a second 15A for the kitchen, which weirdly serves just one outlet (I've put a double socket onto it) in an under-the-stairs cupboard. The induction hob would most likely run from this socket. This circuit still runs when my “main” mains fuse is removed. 

Ive just checked the spec of my Baby Belling, it is 2.5kW.

Thanks for all input, food for thought. I’m in no hurry with all this so I will mull it over 

In reply to Blue Straggler:

Not being funny here. But where would the sparky put a dedicated cooker circuit if you've only got 4 fuses in the CU ??

In reply to Blue Straggler:

Maybe it's time to upgrade to a more modern "fuse box" ? 

In reply to Blue Straggler:

You need to spec your power / fusing for the maxiumum possible load, which is both hobs at full whack and oven at full whack.  If you don't you're going to pop a fuse / trip a breaker on that one occasion when you most need it.   Your hob may only be 2.5kW and the oven 1kW, but appliance power is constantly increasing and the next combi you buy may be 1.5kW.  You will use your hob on full power simply because you can - it'll be so fast it's not worth boiling a kettle to heat a potful of water quickly. 

Power = current x voltage therefore your 2.5+1kW load running at 240V will draw 14.5amps.  Given your house wiring configuration and age of wiring you may well need to embark on a rewire, at least of the kitchen. You may find a sparky won't sign off on using your old fuseboard too (I'm not familiar with UK regs and the rules for upgrading old wiring / fuseboards).

The fact that two of your mains circuits appear to be connected is concerning me greatly - nothing should be 'related'. What happens when you pull the kitchen fuse, does the rest of the house mains go off?  A second circuit for the kitchen suggests that the 15A 'main kitchen' circuit couldn't cope with the load. If the kichen and house mains are connected that also suggests it was done to share the load across the 2 fuses. Or you have bad house wiring. either way it needs sorting!

Don't use a plug for the hob above the worktop, it looks rubbish and the wire is prone to damage.  If you're doing up your kitchen do a proper job. - either chase the wire into the wall and fit a dedicated spur switch, or fit a socket out of sight.

In reply to arch:

He would add one. This was mentioned very briefly when he was here! 

In reply to Toerag:

Thanks. I may have got my terminology wrong somewhere along the way there regarding circuits being “related”.

If the second kitchen circuit fuse is pulled, it affects nothing apart from that one socket. 

Induction hob would likely sit on a worktop which has sockets underneath. I can make the cabling nice and neat.

I am not doing major work here, just a glorified spring clean. 

In reply to marsbar:

This was part of the reason I had the electrician around for a “look see”, to see if it would be relatively straightforward or if it would be opening up a whole new can of worms. I have lots of other house jobs running in parallel with this so need to look at spreading cost and effort. 

In reply to Blue Straggler:

Any new circuit in a kitchen would need to be protected by a RCD  with a 30mA trigger current. So considering you have an old fuse box which couldn't be fitted with an RCD, that means you'd need a consumer unit. The new unit may not be happy with the old wiring and cause nuisance tripping.

I'm very surprised that a 15A fuse isn't continually blowing if it is serving the whole house plugs. Boiling the kettle with the toaster going is likely to draw almost that alone. If you consider a situation where you are cooking an average meal, maybe the oven is on roasting something and you have a hob on to fry something and then you boil the kettle for hot water to cook the veg. In this scenario you're well over the 15A. 

Fuses are also relatively slow to blow and not as effective at protecting you or your property as a modern RCD circuit breaker combo.

Maybe it's time to consider getting the job done and get a rewire or at least a partial rewire to the kitchen.

Maybe fitting something like this:

https://www.screwfix.com/p/wylex-16a-sp-type-b-plug-in-mcb/34544?tc=AT7&...

Could be useful as a cheap starting point that's slightly safer than fuses.

In reply to Blue Straggler:

Loving the Bakelite and the Baby Belling Please keep us posted on your progress. I'm about to do a ceramic to induction upgrade, and have seen a fair few separate circuit load warnings; I'll be taking advice, like you. The sparkys know how to protect their patch, and it could even be that we should listen ...

In reply to gethin_allen:

Sorry if I caused confusion. I have a 30A fuse that I’ve labelled as being for the whole house. If I pull this out, most of the house is turned off apart from one socket in the kitchen, which is protected by a 15A fuse in the fuse box. The rest of the sockets in the kitchen are protected by another 15A fuse in the fuse box, but with this in place and the “main” 30A fuse removed, those kitchen sockets are off. 

Thanks for the tip about the MCBs from Screwfix, a friend elsewhere pointed those out too. 

In reply to freeflyer:

Hi. It might be a while before I do anything ; I mentioned to marsbar above that I have numerous house tasks to get on with. This thread is just me gathering up some advance information. The electrician will be putting in a kitchen extractor fan for me before I even buy any cookers so I’ll revisit these questions with him then. 

In reply to Blue Straggler:

We bought a cheap microwave as a stop gap about 18 years ago and it eventually went last year. Decided to get a combi and it has been great - does a roast chicken in about 20 minutes and crispy baked potatoes in under 10. It plugs into the wall socket. Ours also has a steam function which is good but not used much and a low temp setting for proving bread. Panasonic with a 5 year guarantee.

In reply to Blue Straggler:

I assume your ‘whole house’ isn’t very big? 2 beds? 

If you’re using a plug top cooker, just make sure you can reach the switch and plug easily and without leaning over the hob. If it all goes wrong and you need to turn it off quick, you don’t want to be leaning through the fire.

In reply to marsbar:

The risk of that is that an RCD keeps blowing until you rip out all the ancient wire and find the one with a picture hook’s nail through the live wire...

In reply to Blue Straggler:

So the 'main kitchen' 15A fuse seems to be fed from the 30A one?  What happens if you leave the 30A in place and pull that 'main kitchen' 15A one? Do just the kitchen sockets go off or everything fed by the 30A one as well?

In reply to Scott K:

Thanks. I have been recommended Panasonic but also looking at a Sharp model. I think the oven is not any sort of issue w.r.t. the question of fitting a cooker circuit for an induction hob. 

My notes from electrician's visit indicate around £200 for cooker circuit but they would want to do a whole circuit test in advance of that, for around another £200. I might just get a gas hob  

In reply to Toerag:

Collective sigh of relief, I just checked again and all are INDEPENDENT, I must have got confused the other day when I checked this! Sorry for causing confusion and concern; thanks for making me check again

In reply to Blue Straggler:

Probably best.  

In reply to Blue Straggler:

15 amp for a kitchen is still quite small 

I'm guessing you have a radial circuit rather than a ring because a ring on modern 2.5mm cable would have a 30 ish A breaker and a radial a 20A. I maybe worth investigating what type of circuit you have (see if there's a return to the fuse box) and what cables you have in the plugs etc. Doing this you may be able to safely increase the fuse/breaker capacity to suit the kitchen load. You obviously need to do all the checks and satisfy yourself that this is safe and if not leave it alone and get someone in.

In reply to Blue Straggler:

Tempted to just get one of these for now!


https://www.myappliances.co.uk/Econolux-ART22104-30cm-13a-Plug-Induction-Do...

or

https://www.johnlewis.com/tefal-ih201840-everyday-portable-induction-hob/p5...

or similar!

In reply to Blue Straggler:

Yeah i'd get a gas hob. I've got a nice little induction hob in addition to standard electric hob...... but that's all because when I fist got the house we had gas supply issues so I bought an electric cooker then, and it would be a pain to change now. If I'd had gas to start with, that would have been fine..... and it works with all pans.

Have you not got room for a narrow 13A duel fuel like this?

https://www.argos.co.uk/product/8804916

You could then have something cooking on the hob, do some ironing, and maybe use a hair dryer at the same time!

In reply to Mike Stretford:

Thanks Mike. I do have room for a standard type of cooker but I am trying to be a bit more modular; I have half an idea to squirrel away the combi oven into one of the various nooks and crannies, and just have the two-zone induction hob free standing on a worktop but with the option to move it around if I change my mind etc. 

This has all been kicked off, incidentally, by the purchase of a kayak which finally forced the issue of getting rid of the old gas cooker, as when I bring the kayak in through the canal-towpath-level kitchen door, its nose will impinge into the space now vacated by that cooker! Mentioning this to emphasise that the "sprucing up" of my kitchen is a slightly random improvisation at the moment, as opposed to a committed refit. 

In reply to Blue Straggler:

Kayaks are far more important than kitchens. 

I'm well jell as the kids would say that you can paddle from your door.  

In reply to Blue Straggler:

Is it you that's had damp problems? If so don't get a gas hob as you'll be chucking loads of water into the atmosphere in the room ready to condense out on the cold bits. PS. glad your fuses are independent

In reply to Toerag:

It is me. Not huge problems but certainly something I am looking to minimise. Thanks for the heads up. Why do gas hobs create more condensation? Is it the expansion of gas from the outlets forming a vapour? Surely that burns straight off as soon as you light it....but it seems that I am lacking in some basic science here 😃

Useful thread, thanks to all for various inputs. I am almost certainly going to get an officially “plug and play” induction or ceramic dual zone hob and some MCBs. 

In reply to Blue Straggler:

Water is a by product of burning gas.

Good thing with electric, all your dodgy emissions are out of sight and mind many miles away!  😄

In reply to Taylor's Landlord:

This is why I only got a C in A Level Chemistry 🤣

If I cook and eat enough vegetables, pulses and fibres I am sure I will have plenty of dodgy emissions in my house! 

In reply to Taylor's Landlord:

It is, but nowhere near as much as you’ll get off the food you’re heating or steam from boiling a kettle. 

In reply to Scott K:

I was just about to endorse your post when the bulb went on mine. I doubt it's covered by the guarantee and it's a bastard to replace.

In reply to Tom Valentine:

Is the bulb essential?