UK Gas Cooker conked and electrical cooker replacement

advicewelcom · Nov 5, 2021

Hi, quick posting - welcome any advice as new to this stuff...

Have a Howden HJA 0150 gas grill/oven with a broken thermostat that and can't get a replacement (grill igniting but no gas coming out of oven burners when on).

The Howden grill/oven is on a ring in the kitchen which has following appliances on it:
-microwave
-fridge freezer
-kettle
-toaster
-a Howden gas hob
-the busted Howden grill/oven
-couple of kitchen sockets generally not used

It all goes back to a RCD with a fuse that says - MTN132 b32 hanger fuse

There is an electrical wall connection for the grill/oven, with (I think) a 6mm wire for the ring (and not the thicker 10mm wires used for showers).

I may want to replace with just an electrical gill/oven. So some questions...

-Is there is max kilowatt oven that I could just wire into the current wall socket (which is used for the current grill/oven electrical ignition connection)?

-Would I need to replace the fuse in the RCD for the main? And is so with what?

-Would these things ensure the fuse would not trip if the oven was switched on?

-There are lots of electrical ovens but the instructions say they should be wired directly to the fuse box, so wondering if there is one which can just run from this ring main (if I upgrade the fuse)?

Would hate to buy an electrical oven and then its a nightmare and expense to fit it (the fuse box is currently full).

Welcome advice.

(attached pic of gas connection, and wall sockets for hob and grill/oven)

Avo Mk8 · Nov 6, 2021

advicewelcom said:
This is the fuse (hanger is the manufacturer) and its looks 32A

Yep. Fine. Leave as it is protecting the circuit.

advicewelcom said:
Yes, plug in one seems fine - had to check as even if its plug in, was worried it could keep tripping the fuse if someone decided to make a cuppa and toast whilst chips were in the oven and warming some milk in the microwave. with phone recharging in plug.

If you turn all those on, I would wager the MCB won't trip, unless you buy an unusually powerful oven.

advicewelcom said:
Search results for "plug in ovens" | ao.com - https://ao.com/l/search/101/99/?search=plug%20in%20ovens
...looks like there are options and hopefully they don't have any small print saying it needs its own line to the fuse box.

The first 'recommended' one at the top of that list is 2.8kW, so that's pushing it. Go for 2.2kW max.
You obviously need to pick one the right physical size to fit your cabinet!
If they come with a plug, no small print. I suggest keeping the plug on it and having an electrician fit a decent socket in place of that FCU.

advicewelcom said:
Just didn't know if anyone else was in this position and had a recommendation for an oven that goes in no hassle for reasonable price?

I can't tell you which oven you would like! Research them on the basis of physical size, power consumption (2.2kW or under), reviews, maybe customer satisfaction ratings if you think you can trust them!

advicewelcom said:
I assume its a case of stripping plug so its fit it into the FCU.

See above. Don't cut the plug off (cue debate about invalidating warranty, not). Plug it in.

advicewelcom said:
I would need someone to cap off and cert the gas supply I guess?

Yes. And preferably someone to fit a good quality 13A socket in place of the FCU.

advicewelcom · Nov 8, 2021

Avo Mk8 said:
Yep. Fine. Leave as it is protecting the circuit.

If you turn all those on, I would wager the MCB won't trip, unless you buy an unusually powerful oven.

The first 'recommended' one at the top of that list is 2.8kW, so that's pushing it. Go for 2.2kW max.
You obviously need to pick one the right physical size to fit your cabinet!
If they come with a plug, no small print. I suggest keeping the plug on it and having an electrician fit a decent socket in place of that FCU.

I can't tell you which oven you would like! Research them on the basis of physical size, power consumption (2.2kW or under), reviews, maybe customer satisfaction ratings if you think you can trust them!

See above. Don't cut the plug off (cue debate about invalidating warranty, not). Plug it in.

Yes. And preferably someone to fit a good quality 13A socket in place of the FCU.

Thanks. If I'm calling out an elecy to fit the socket and a gas peep to cap the gas - the economics of this are not going to work out in favour of electric (may be cheaper to buy a gas one - which isn't first choice as boilers and gas doesn't look like long term strategy considering the prices right now).

Doesn't help when manufactures instructions for plug fitting ovens are confusing...

"This appliance must not be connected to an ordinary domestic power point. This product comes fitted with a BS plug and cord."

Would it really require an elecy to replace the current FCU? Aren't the wall plates standard and just a case of checking everything is off with a multi-meter and putting the correct terminals in the right place to the below?

MK Logic Plus 13A 1-Gang DP Switched Plug Socket White - https://www.screwfix.com/p/mk-13a-1-gang-dp-switched-plug-socket-white/14790#product_additional_details_container

Avo Mk8 · Nov 8, 2021

advicewelcom said:
Doesn't help when manufactures instructions for plug fitting ovens are confusing...

"This appliance must not be connected to an ordinary domestic power point. This product comes fitted with a BS plug and cord."

I agree. That's bizarre. The max wattage quoted is 2540W, which is about a 10A load.
They seem to be saying 'don't use the plug we supply, cut it off and connect to a FCU'
(or maybe they mean use an industrial metal clad power point ?)

So I retract all my "just plug it in" comments
I suspect 'Bush' are erring on the side of caution, having had customers complain their plug has melted or such like! (Most likely caused by a socket with loose contacts)

advicewelcom said:
Would it really require an elecy to replace the current FCU? Aren't the wall plates standard and just a case of checking everything is off with a multi-meter and putting the correct terminals in the right place to the below?
MK Logic Plus 13A 1-Gang DP Switched Plug Socket White - https://www.screwfix.com/p/mk-13a-1-gang-dp-switched-plug-socket-white/14790#product_additional_details_container

No. Yes. Just as long as work is done safely and competently.
Except if you bought the Bush fan oven, in which case apparently you should use the existing FCU !

advicewelcom · Dec 3, 2021

Avo Mk8 said:
If you add up typical consumption figures for the appliances you have, and include a new plug-in oven, it's not enough to trip the MCB.
1.7kW -microwave
0.5 kW -fridge freezer
2kW -kettle
1.2 KW -toaster
2.2 kW -a new oven
= 7.6kW = about 32 amps, depending on exact mains voltage
This doesn't include an allowance for the remaining sockets, where you say 'generally not used'
Although reaching the limit for the circuit, from a pragmatic point of view, will you ever have all appliances on at once?
Don't fiddle with your electrical installation.
As Tel said in post #8, just get an oven that is designed to be plugged in, and plug it in!

Thanks. Kitchen may have 5 people in it, so toaster, microwave, hob, kettle and possible oven could be on - fridge will always be on.

I heard electric is the way to go considering John Lewis have 100's of ovens and only 1 is gas.

Looking around at ovens and quite fancy this BEKO one, seems to tick the boxes for price point and simple:

BEKO AeroPerfect RecycledNet BBXIF22100S Electric Oven

Manual is a bit hopeless (cheers Beko), but it looks likes it a 13AMP fuse spur connection according to the Curry's spec sheet...
"This product requires hardwiring to a 13 Amp fuse and should be installed by a qualified installer, such as one of our Team Knowhow experts"

Seems like a wire into the fuse spur and get the gas capped off with a Gas certified engineer.

It is 2.3KW and wondering if it will be okay considering the current ring setup?

Welcome any views.

telectrix · Dec 3, 2021

It is 2.3KW and wondering if it will be okay considering the current ring setup?

regs. suggest that any cooking allpiance > 2.2kW should be on it's own dedicated circuit. this is to avoid overloading a ring that may be close to capacity with other appliances.

Avo Mk8 · Dec 3, 2021

advicewelcom said:
It is 2.3KW and wondering if it will be okay considering the current ring setup

To me it looks a good option for the oven, especially since the manufacturer's instructions say to connect it to the exact type of connection you have. I did suggest 2.2kW max, but 0.1kW over is not going to make a material difference in this scenario. I hear what Telectrix says, but from a pragmatic point of view 2.3kW will not overload the accessory or the cable.

That model has a grill and a fan oven. I believe the oven element is 1.8kW. Even when you have both grill and oven on, the oven element will soon switch itself off after a few minutes when the oven reaches temperature, so the average current draw will be very modest.
Even with 5 people in the kitchen, there's a limit to how many hours of toasting you can do continuously!
And if microwaving, it won't be on full power for long unless you're trying to set fire to the food!
And the same applies to the kettle - everyone can have their cup-a-soup several times over before the circuit feels a thing!
I really think your average consumption, even with all the appliances being used, will not exceed, probably won't even come close to, the rating of the circuit.

There are many people with a washing machine, tumble dryer, dishwasher in their kitchen as well as all the other appliances. Those are not present in your situation I believe. Aware of the regs, but just trying to add a note of pragmatism here

advicewelcom · Dec 3, 2021

Avo Mk8 said:
To me it looks a good option for the oven, especially since the manufacturer's instructions say to connect it to the exact type of connection you have. I did suggest 2.2kW max, but 0.1kW over is not going to make a material difference in this scenario. I hear what Telectrix says, but from a pragmatic point of view 2.3kW will not overload the accessory.

That model has a grill and a fan oven. I believe the oven element is 1.8kW. Even when you have both grill and oven on, the oven element will soon switch itself off after a few minutes when the oven reaches temperature, so the average current draw will be very modest.
Even with 5 people in the kitchen, there's a limit to how many hours of toasting you can do continuously!
And if microwaving, it won't be on full power for long unless you're trying to set fire to the food!
And the same applies to the kettle - everyone can have their cup-a-soup several times over before the circuit feels a thing!
I really think your average consumption, even with all the appliances being used, will not exceed, probably won't even come close to, the rating of the circuit.

There are many people with a washing machine, tumble dryer, dishwasher in their kitchen as well as all the other appliances. Those are not present in your situation I believe. Aware of the regs, but just trying to add a note of pragmatism here

Oh Crumbs. Good point....

Just remembered I have a Washing Machine & Dryer (Hotpoint RD 966 J) in the kitchen and checked its on the same ring(!!)

So we have...

?? KW - some kitchen sockets hardly used
Low KW? - Gas Hob
1.7 kW - microwave
0.5 KW - fridge freezer
2.0 kW - kettle
1.2 KW - toaster
?? KW - Hotpoint Washer & Dryer RD 966 J
2.3 KW - new BEKO potential oven

Is the advice still that its an okay to add this oven to the same ring?

As per above I understand that upgrading the Hager thingy-ma-jig fuse cartridge from 32Amps is not going to make a difference.

Just have some elderly people in the house and they would not be able to sort a trip so have to do everything to avoid that.

Welcome any pointers as just don't to be stuck with an flippin' tripping oven.

(Oven returns policy means they won't take it back if switched on so can't really test it beforehand).

Avo Mk8 · Dec 3, 2021

advicewelcom said:
Oh Crumbs. Good point....

Just remembered I have a Washing Machine & Dryer (Hotpoint RD 966 J) in the kitchen and checked its on the same ring(!!)
Welcome any pointers as just don't to be stuck with an flippin' tripping oven.

(Oven returns policy means they won't take it back if switched on so can't really test it beforehand).

Hotpoint RD 966 is 1.85kW
If an electrician was designing your kitchen circuit knowing what we now know, he would provide 2 rings, or at least a separate cooker feed.

If it were my house, and I was living there, I confess I would probably put the cooker on the ring, and use the knowledge that it's not wise to run everything at once. But I'm not suggesting you do that

With others living there, particularly if elderly or vulnerable, needs to be handled properly. Back to gas or a separate circuit?

Afterthought - is there by any chance an adjacent room with another ring, the other side of a kitchen wall? Was just thinking a spur off a different circuit could feed say the washer, alleviating the load on the kitchen circuit, so you could possibly proceed as before

advicewelcom · Dec 3, 2021

Gosh, there is not much chance of a dedicated wire as no slots on the fuse board even if I could run a dedicated cable to the board.

So far, we have the below...
?? KW - some kitchen sockets hardly used
Low KW? - Gas Hob
1.7 kW - microwave
0.5 KW - fridge freezer
2.0 kW - kettle
1.2 KW - toaster
1.85 KW - Hotpoint Washer & Dryer RD 966 J
2.3 KW - new BEKO potential oven

With the above I assume a 2.0KW oven wouldn’t make much of a difference would it?? Just to understand how the trip risk changes with KW change?

I suppose the washing machine drying function would take a lot more energy then just the washing machine washing clothes (as they tend to be energy efficient)? So a house rule not to run the oven when drying clothes – would that work considering what is on the circuit presently?

Avo Mk8 said:
Afterthought - is there by any chance an adjacent room with another ring, the other side of a kitchen wall? Was just thinking a spur off a different circuit could feed say the washer, alleviating the load on the kitchen circuit, so you could possibly proceed as before

Actually, above the washing machine there is a gas boiler (Vailant Turbomax VUW 282 E – 28KW), on a separate circuit shared with a hive system and a couple of sockets next to it which goes to a Hager 20A fuse (pics attached). I assume a gas boiler does not have much elecy draw? Would it be relatively easy to get the washing machine wired into that system/spur if it trips the main ring circuit?

Avo Mk8 · Dec 3, 2021

advicewelcom said:
Gosh, there is not much chance of a dedicated wire as no slots on the fuse board even if I could run a dedicated cable to the board.

if you prefer Amps:
?? - some kitchen sockets hardly used (so far ignored)
ignore! - Gas Hob
7A - microwave
2A - fridge freezer
8.3A - kettle
5A - toaster
7.7A - Hotpoint Washer & Dryer RD 966 J
9.6A new BEKO potential oven

So without your new oven, max possible current in kitchen circuit, ignoring sockets hardly used (which we should not) is 30A, which is the limit for the circuit. The reality is that "diversity" means actual instantaneous load would be less.

advicewelcom said:
I suppose the washing machine drying function would take a lot more energy then just the washing machine washing clothes (as they tend to be energy efficient)? So a house rule not to run the oven when drying clothes – would that work considering what is on the circuit presently?

The machine consumption figure includes drying. If you have a "house rule" it might avoid tripping, but it doesn't make the circuit design correct.

advicewelcom said:
Actually, above the washing machine there is a gas boiler (Vailant Turbomax VUW 282 E – 28KW), on a separate circuit shared with a hive system and a couple of sockets next to it which goes to a Hager 20A fuse (pics attached).

Possibly a 20A radial which it would be good to get confirmed by an electrician.

advicewelcom said:
I assume a gas boiler does not have much elecy draw? Would it be relatively easy to get the washing machine wired into that system/spur if it trips the main ring circuit?

Yes boiler power requirement very modest. Conceivably if you could plug about 9 amps worth of load there, you'd be "OK".
What's plugged in it already? Anything on the list !? If that's the washing machine below, could you plug that in?

Up to the point you made me aware of the washing machine, I felt comfortable that cable current would not be exceeded for "long periods" (433.1.204), but now with the washing machine and oven included you are into overload and tripping territory.

This is an uncomfortably borderline situation. Anyone here on the side of pragmatism?

advicewelcom · Dec 4, 2021

Avo Mk8 said:
The machine consumption figure includes drying. If you have a "house rule" it might avoid tripping, but it doesn't make the circuit design correct.
Possibly a 20A radial which it would be good to get confirmed by an electrician.Yes boiler power requirement very modest. Conceivably if you could plug about 9 amps worth of load there, you'd be "OK".What's plugged in it already? Anything on the list !? If that's the washing machine below, could you plug that in?

Kitchen Circuit 1: 32A
ignore A - some kitchen sockets hardly used
ignore A - Gas Hob
7A - microwave
2A - fridge freezer
8.3A - kettle
5A - toaster
7.7A - Hotpoint Washer & Dryer RD 966 J
Total so far = 30A
9.6A - New BEKO oven
Total of all = 39.6A

If you had Fridge, Washing machine, Oven on at the same time 19.3A - leaves space for a kettle, but could trip if you have kettle and microwave going?

Can’t I just upgrade the fuse cartridge in the hager fuse box to 40A or something for this circuit?

And are your saying for the other circuit…

Kitchen Circuit 2: 20A
A? - Valiant Boiler
A? – Hive Central Heating switch
A? – Couple of plugs hardly used
Total so far = 11A?
9A remaining so maybe could move Hotpoint washing machine to this?

Thus would then allows Circuit 1: to have BEKO oven and everything on, and still be under (39.6-7.7A) = 31.9A?

Avo Mk8 · Dec 4, 2021

advicewelcom said:
Kitchen Circuit 1: 32A
ignore A - some kitchen sockets hardly used
ignore A - Gas Hob
7A - microwave
2A - fridge freezer
8.3A - kettle
5A - toaster
7.7A - Hotpoint Washer & Dryer RD 966 J
Total so far = 30A
9.6A - New BEKO oven
Total of all = 39.6A

Correct

advicewelcom said:
If you had Fridge, Washing machine, Oven on at the same time 19.3A - leaves space for a kettle, but could trip if you have kettle and microwave going?

When it comes to 'tripping' due to slightly excess current in the circuit, it's all about the combination of the average degree of overload, and the time it lasts. It's done by a bimetallic strip arrangement. The behaviour is embedded in the design of the MCB's. For your type B mcb, a small excess current, up to 1.13 times the rating of the mcb, will take more than an hour to trip (remenbering that's the average current over all that time).
If the average current increases to 1.4 times the mcb rating, it will trip in under an hour. From there the more the overload, the quicker it trips.
So it's difficult to answer your question, because it depends heavily on what the average current is over a period of time.
But the point is to arrive at a safe circuit that meets regulations, not just be driven by 'will it trip', which might be your main concern, but you don't want the house catching fire either, do you!

advicewelcom said:
Can’t I just upgrade the fuse cartridge in the hager fuse box to 40A or something for this circuit?

No you absolutely must not. For your ring final circuit in 2.5mm T&E, the mcb must be 32A and no more, otherwise the cable is not protected. The cable is not rated to share 40A. (all set out in the Wiring Regulations)

advicewelcom said:
And are your saying for the other circuit…

Kitchen Circuit 2: 20A
A? - Valiant Boiler
A? – Hive Central Heating switch
A? – Couple of plugs hardly used
Total so far = 11A?
9A remaining so maybe could move Hotpoint washing machine to this?

3A Vailant boiler (takes less, but that's the fuse)
3A Hive (as above)
Total so far 8A?
12A remaining - plenty for washing machine.

advicewelcom said:
Thus would then allows Circuit 1: to have BEKO oven and everything on, and still be under (39.6-7.7A) = 31.9A?

Precisely
And bear in mind the oven without the grill on would be 7.6A not 9.6A; we do have 'worst case' figures here.

advicewelcom · Dec 6, 2021

Avo Mk8 said:
Precisely
And bear in mind the oven without the grill on would be 7.6A not 9.6A; we do have 'worst case' figures here.

Thanks, will take a look at all the great info here.

I did take a look at the washing machine/boiler wiring arrangement, pics attached...

1- Washing machine pulled out
2- Wall switch to power socket for washing machine
3- Single plug socket in underneath area for washing machine
4- Wiring access around the boiler

I assume the best way is to get an elecy to run a cable down from that double plug next to the boiler down to the fuse spur for the oven? (which is under the kitchen top and behind the oven)

Is it that straightforward to wire the oven into that boiler/washing machine 20A ring?

Avo Mk8 · Dec 6, 2021

If you are contemplating making any changes to the fixed wiring, I feel it's essential you get an electrician to look at the options. You need to have it confirmed that our theories about the kitchen ring, and the boiler radial, are actually correct, and then the electrician can consider the wisdom and practicality of what you're suggesting.

I didn't intend to suggest putting the oven on the boiler circuit, I don't think that is a good idea.

If it were me, I would pass the flex of the washing machine up behind the worktop, probably in the boxing-in of the pipes, and plug it into the socket by the boiler. That would avoid the possibility of excessive load on the kitchen ring, so you could then wire the oven into the spur already provided for it. And thus no changes to the fixed wiring.

advicewelcom · Dec 6, 2021

Avo Mk8 said:
I didn't intend to suggest putting the oven on the boiler circuit, I don't think that is a good idea. If it were me, I would pass the flex of the washing machine up behind the worktop, probably in the boxing-in of the pipes, and plug it into the socket by the boiler. That would avoid the possibility of excessive load on the kitchen ring, so you could then wire the oven into the spur already provided for it. And thus no changes to the fixed wiring.

So, if the below is correct in the way its wired, you're suggesting plugging the Hotpoint Washer Dryer into the Kitchen Circuit 2 and then the New BEKO electrical oven would be okay on Kitchen Circuit 1?

Kitchen Circuit 1: 32A
ignore A - some kitchen sockets hardly used
ignore A - Gas Hob
7A - microwave
2A - fridge freezer
8.3A - kettle
5A - toaster
7.7A - Hotpoint Washer & Dryer RD 966 J
Total so far = 30A
9.6A - Potential New BEKO oven
Total of all = 39.6A

Kitchen Circuit 2: 20A
3A - Vailant boiler (takes less, but that's the fuse)
3A - Hive (as above)
1A - Couple of plugs hardly used?
Total so far 7-8A?