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)

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?

Avo Mk8 · Dec 6, 2021

advicewelcom said:
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?

Yes. If you did that, with every appliance you have running simultaneously flat out, total load would be:
Kitchen circuit 1 (rated at 32A) 31.9A
Kitchen circuit 2 (rated at 20A) 14.7A

Allowing for diversity, no problem.
No fiddling with fixed installation, no additional expense, no tripping.

advicewelcom · Dec 6, 2021

Avo Mk8 said:
Yes. If you did that, with every appliance you have running simultaneously flat out, total load would be:
Kitchen circuit 1 (rated at 32A) 31.9A
Kitchen circuit 2 (rated at 20A) 14.7A
Allowing for diversity, no problem.
No fiddling with fixed installation, no additional expense, no tripping.

Sounds fabulous. Just have to double check I got the right things on the right rings.

But... they have sold out of those ovens at Currys

I assume any 9.7A max oven is going to work?

In Watts, Is the calculation done by:
P (power) = V (volts) x I (current).
W = 240V x 9.7A
W = 2.328kW max oven (with no plug).

Avo Mk8 · Dec 6, 2021

advicewelcom said:
I assume any 9.7A max oven is going to work?

In Watts, Is the calculation done by:
P (power) = V (volts) x I (current).
W = 240V x 9.7A
W = 2.328kW max oven (with no plug).

Yes to both

Every time we discuss an oven, the current goes up a tiny bit!

(only joking)
I wouldn't worry about an extra half an amp.

Ex-display from a reputable supplier might be worth looking at.

Hope you get the matter sorted.

brianmoooore · Dec 7, 2021

The power rating of any appliance sold in the UK should be stated at 230 volts, not 240, which will reduce the current drawn in proportion.
I know electric shower suppliers still con their customers by stating the power output for 240 volts, but I haven't checked if the same applies for cookers.

advicewelcom · Dec 7, 2021

brianmoooore said:
The power rating of any appliance sold in the UK should be stated at 230 volts, not 240, which will reduce the current drawn in proportion.
I know electric shower suppliers still con their customers by stating the power output for 240 volts, but I haven't checked if the same applies for cookers.

W = 2.231kW - 2.328kW max

brianmoooore · Dec 7, 2021

That's at 240V, according to your previous post. A cooker is a resistive load, and this one equates to 24.74 ohms. At 230V, this gives 9.3A or 2139W

advicewelcom · Dec 8, 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 - 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?

Oh Gawd...

Just checked and it looks like the twin sockets next to the boiler are on Circuit 1 and the fuse spur on the right for the hob electrics in also on Circuit 1 (pic attached)

So looks like this....

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)
Total so far 6A?

Which means plugging that washing machine into those twin wall sockets will keep it on Circuit 1.

Is there any way to wire a plug or connect into that boiler fused spur for the washing machine? Or culd the twin sockets be easily connected to that boiler fused spur?

Avo Mk8 · Dec 8, 2021

advicewelcom said:
Is there any way to wire a plug or connect into that boiler fused spur for the washing machine? Or culd the twin sockets be easily connected to that boiler fused spur?

You need to establish exactly what circuit that boiler fused spur is on, what cable size, and what breaker.
Are you sure that's not part of circuit 1 just as everything else seems to be ?

advicewelcom · Dec 9, 2021

Avo Mk8 said:
You need to establish exactly what circuit that boiler fused spur is on, what cable size, and what breaker.
Are you sure that's not part of circuit 1 just as everything else seems to be ?

Hi, checked it out and after turning off Circuit 1 the boiler (and Hive) stayed on, everything else was off. Vice Versa. The twin sockets next to the Boiler are on Circuit 1 (so no point plugging washing machine into those twin sockets). Below is accurate...

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)
Total so far 6A?

Attached pics show the fused spur right and left.

Left fused spur is wired to boiler, right fused spur is wired to the gas hob. Twin sockets are on Circuit 1.

Any method to get the twin sockets onto Circuit 2 so can plug washing machine into it?

Avo Mk8 · Dec 9, 2021

advicewelcom said:
Any method to get the twin sockets onto Circuit 2 so can plug washing machine into it?

I'll try again to explain.
it's not possible to say unless you know what size cable runs to the boiler spur, what size breaker it's on, and whether it's part of a ring serving other accessories as well, or is a radial circuit (ie one cable going from consumer unit to that fcu.), and if the latter you need to be sure of the current carrying capacity of the cable, and if it's serving anything else.

If you can answer the following, there might be a chance of deciding if it's practical. Otherwise you'll need an electrician to investigate and advise (which I recommend).

What markings are on the Hager breaker that serves the boiler fcu - in particular what current rating?
If there's a label below the breaker, what does it say (eg 'boiler!', or 'downstairs lights!')
Does anything else in the house go off if you switch off that boiler breaker (needs checking carefully)
Is it a single twin and earth cable that goes into the back of the boiler fcu, or are there two sets of cables?
Is the cable in the back of the boiler fcu the same physical size as the cable in the gas hob fcu (eg 2.5mm T&E)?

I made the suggestion to plug the washing machine into that socket, as a possible way of achieving the installation of the oven, because it avoided you having to interfere with the fixed installation. Now we are back playing with the house wiring, I think you would be better served getting an electrician in to solve the problem. He would see the best way of doing it, rather than us trying to divine it remotely.
However if you can answer the questions above, we might hazard a guess as to whether it could be a straightforward job for that electrician!

advicewelcom · Dec 9, 2021

Avo Mk8 said:
I'll try again to explain.
it's not possible to say unless you know what size cable runs to the boiler spur, what size breaker it's on, and whether it's part of a ring serving other accessories as well, or is a radial circuit (ie one cable going from consumer unit to that fcu.), and if the latter you need to be sure of the current carrying capacity of the cable, and if it's serving anything else.

If you can answer the following, there might be a chance of deciding if it's practical. Otherwise you'll need an electrician to investigate and advise (which I recommend).

What markings are on the Hager breaker that serves the boiler fcu - in particular what current rating?
If there's a label below the breaker, what does it say (eg 'boiler!', or 'downstairs lights!')
Does anything else in the house go off if you switch off that boiler breaker (needs checking carefully)
Is it a single twin and earth cable that goes into the back of the boiler fcu, or are there two sets of cables?
Is the cable in the back of the boiler fcu the same physical size as the cable in the gas hob fcu (eg 2.5mm T&E)?

I made the suggestion to plug the washing machine into that socket, as a possible way of achieving the installation of the oven, because it avoided you having to interfere with the fixed installation. Now we are back playing with the house wiring, I think you would be better served getting an electrician in to solve the problem. He would see the best way of doing it, rather than us trying to divine it remotely.
However if you can answer the questions above, we might hazard a guess as to whether it could be a straightforward job for that electrician!

Avo Mk8 said:
If you can answer the following, there might be a chance of deciding if it's practical. Otherwise you'll need an electrician to investigate and advise (which I recommend).

What markings are on the Hager breaker that serves the boiler fcu - in particular what current rating?
If there's a label below the breaker, what does it say (eg 'boiler!', or 'downstairs lights!')
Does anything else in the house go off if you switch off that boiler breaker (needs checking carefully)
Is it a single twin and earth cable that goes into the back of the boiler fcu, or are there two sets of cables?
Is the cable in the back of the boiler fcu the same physical size as the cable in the gas hob fcu (eg 2.5mm T&E)?

I made the suggestion to plug the washing machine into that socket, as a possible way of achieving the installation of the oven, because it avoided you having to interfere with the fixed installation. Now we are back playing with the house wiring, I think you would be better served getting an electrician in to solve the problem. He would see the best way of doing it, rather than us trying to divine it remotely.

Hi, thanks, will probs get elecy in, but is hard to find anyone and more chance if I can be specify exactly what the job is and some of the homework is done prior to them coming onsite.

Pic attached of the RCD/MCB box...

Diagram Marking 1 - Is for circuit 1 and is hager MTN 132 B32 - 32A
(Label says sockets but covers things in the kitchen already stated)

Diagram Marking 2 - is for circuit 2 and is hager MTN 120 B20 - 20A
(Label says "Boiler and Twin Sockets" - but the twin sockets next to boiler are actually on circuit 1 when tested).

Have hunted around and there aren't any other "twin sockets" for circuit 2 (would be great if there was) - assume for this purpose there isn't or anything else connected (other than the Hive which is powered from boiler)

Right fused spur pic shows approx wiring size and it seems like there is a wire coming from the twin socket side and also from the wall via top of the socket metal back box. Hence the twin sockets are on circuit 1? (follows from the socket testing).

Left fused spur has one wall wire coming in from the top of the socket metal box and one leaving the bottom of the fused spur casing to the boiler. Hive is connected to the boiler.

Would the quick solution be to connect that twin socket to the left fuse spur on circuit 2 and then plug the washing machine into that socket? Or is there an alternative if this isn't poss?

Avo Mk8 · Dec 9, 2021

advicewelcom said:
Hi,Would the quick solution be to connect that twin socket to the left fuse spur on circuit 2 and then plug the washing machine into that socket?

You seem to have a 20A radial with only the boiler on it, so basically "yes" !
As long as the 13A socket is safely taken out of the radial, and the ring is kept properly continuous after (eg Wago's)
Whoever does it needs to be competent!

advicewelcom · Dec 9, 2021

Avo Mk8 said:
You seem to have a 20A radial with only the boiler on it, so basically "yes" !
As long as the 13A socket is safely taken out of the radial, and the ring is kept properly continuous after (eg Wago's)
Whoever does it needs to be competent!

Ok, hopefully I find someone, but if I can't, to take this on, I could...
-Turn both circuits off and test they are off with multimeter
-Pull out the wire connecting the twin sockets into the right fuse spur
-Connect it up to the left fuse spur in the same way
-Close everything up and test
-Plug washing machine into twin sockets
-Fit electrical oven

Not my preference to do myself, but cannot wait for someone to turn up if the oven has to be replaced. There are no gotcha's here or complications?

DPG · Dec 9, 2021

Surely this needs an electrician in. It's very close to step-by-step instructions on reconfiguring a circuit.

Avo Mk8 · Dec 9, 2021

advicewelcom said:
Ok, hopefully I find someone, but if I can't, to take this on, I could...
-Turn both circuits off and test they are off with multimeter
-Pull out the wire connecting the twin sockets into the right fuse spur
-Connect it up to the left fuse spur in the same way
-Close everything up and test
-Plug washing machine into twin sockets
-Fit electrical oven

Not my preference to do myself, but cannot wait for someone to turn up if the oven has to be replaced. There are no gotcha's here or complications?

Just to clarify - I misunderstood how the 13A socket was wired, sorry my error - you’re saying there is just a single cable going from it to the fused spur on the right?
In which case what you describe is a viable way of having it done.

advicewelcom · Dec 10, 2021

Avo Mk8 said:
Just to clarify - I misunderstood how the 13A socket was wired, sorry my error - you’re saying there is just a single cable going from it to the fused spur on the right?
In which case what you describe is a viable way of having it done.

Yes, think so - I assume its a ring - so the wall power wire going to the right fuse spur (for the hob) and then cable going to the twin socket.

Hopefully I can open all the sockets up - if the right fuse spur is same as left spur - can wire that up to the twin sockets - then twin sockets will be on Circuit 2.

Job's a good 'un - can have turkey for Xmas.

... but stay tuned, as betcha something will throw spanner in works.

advicewelcom · Dec 17, 2021

Hi, took all the sockets apart and had a good look. Its like the attached diagram, with the right hand of the twin socket wired to the hob FCU.

I assume I can just wire it up with the red line to the Boiler FCU instead and then plug the washing machine into the left hand twin socket.

This will work okay considering the above?

Avo Mk8 · Dec 17, 2021

advicewelcom said:
Hi, took all the sockets apart and had a good look. Its like the attached diagram, with the right hand of the twin socket wired to the hob FCU.

I assume I can just wire it up with the red line to the Boiler FCU instead and then plug the washing machine into the left hand twin socket.

This will work okay considering the above?

What you've drawn as the original circuit in black, would be an unusual way for the house to be wired.
Also not quite sure what the red dotted line represents, you're not thinking each socket is wired independently? (they're not!).

I would expect a kitchen ring to be wired from one accessory to the next, so from 'fuse box' to twin socket, then to gas hob fcu, then to remainder of ring, and back to the 'fuse box'. ie no link where you have the word 'circuit'.
I know your sketch is only illustrative, but you have drawn cable "T junctions" in the middle of nowhere - they must be at an accessory, so think carefully about how it forms a 'ring'
Disconnecting as you show, I believe, would break the ring (because I think the horizontal black connection doesn't exist), so the modification would reduce the current carrying capacity of the circuit, become non-compliant with the regulations, and be dangerous.
Normally taking an accessory out of a ring requires re-joining the cables as they were, with Wago's etc, to main the continuity of the ring.

As has been said before, this forum is not supposed to give step by step advice for DIY. I'm explaining the above because I don't want you to create a dangerous situation.
Working on the fixed installation of a house requires certainty and competence in what is being done.
You have described earlier in general terms how to solve the issue you had.
Just make sure it's executed correctly.

I think it's best if I don't respond further.
Keep safe.

advicewelcom · Dec 17, 2021

Appreciate the contact and nearly there. Issues is current COVID stuff not able to get an elecy in with older people in the house and there is an turkey that needs roasting for Crimbo, so the clock is ticking on oven installation. Thus grateful for any feedback on the below...

...your right, it must be a ring (can disconnect and check), but that explains that wire from twin socket to the right hob FCU.

DIAGRAM ATTACHED.

If if connect up the ring with connector block and insulation tape (behind the socket) to completed the kitchen circuit.

Then add addition 2.5 T&E (RED line) to connect the twin socket to the boiler FCU.

2.5 T&E it's good for 26Amps to support the twin sockets. Then plug washing machine into that.

The fuse in the Boiler FCU has to be 13A?

.. Is that job done?

brianmoooore · Dec 17, 2021

The wiring arrangement in the diagram you posted above would be compliant.
If you end up with connections from two different circuits in the same enclosure, a warning label should be fitted.

UK Gas Cooker conked and electrical cooker replacement

Attachments

-

Attachments

-

-

-

-

-

Attachments

-

Attachments

-

Attachments

-

-

-

Attachments

-

Attachments

-

Similar Threads

OFFICIAL SPONSORS