UK Gas Cooker conked and electrical cooker replacement

[advicewelcom]

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)

 

[DPG]

This really does need an electrician getting in.

 

[advicewelcom]

This really does need an electrician getting in.

Try getting one, and then try dealing with the risks with virus in the household. I think I will have get elecy if it keeps tripping out. But will try the below first...


GENERAL TEST APPROACH
-Do wiring again and careful of N & E shorts
-Check the RCD
-If tripping lift Boiler FCU Neutral to boiler and see if can reset RCD

If still have tripping issues:
-Check whats going off and how in fuseboard
-Take photo of fuseboard circuit
-Do some MM testing with fuseboard



... seem ok?

 

[marconi]

OK - V's between Boiler FCU Earth to double socket Earth

The fact that you measure a voltage albeit small between the earth conductor of the boiler fcu and the earth conductor of the double socket on the right indicates a break in continuity of an earth conductor (more correctly circuit protective conductor cpc). This fault could be on the ring or on the radial to fcu or both. If the cpc between the fcu and the consumer unit and the cpcs of the ring back to the cu where complete and connected correctly then no voltage can exist between the boiler and double socket cpcs because they are effectively joined together. This state of affairs can cause an rcd to trip.

Time to call in a sparks with the right test equipment.

You can forget about taking the lid off the cu.

 

[advicewelcom]

OK - V's between Boiler FCU Earth to double socket Earth

The fact that you measure a voltage albeit small between the earth conductor of the boiler fcu and the earth conductor of the double socket on the right indicates a break in continuity of an earth conductor (more correctly circuit protective conductor cpc). This fault could be on the ring or on the radial to fcu or both. If the cpc between the fcu and the consumer unit and the cpcs of the ring back to the cu where complete and connected correctly then no voltage can exist between the boiler and double socket cpcs because they are effectively joined together. This state of affairs can cause an rcd to trip.

Haven't measured anything yet, assume this Earth to Earth V measurement test is to be done before any wiring changes to the Boiler radial and Kitchen Ring (seperate circuits) - and should come back with a 0v if there is no break in continuity.

 

[Avo Mk8]

Just have to clarify this (PANIC STATIONS).

You are saying to connect from the Boiler FCU supply input to the TWIN SOCKET?

Think you're saying don't connect from the FCU output going to the boiler.

Attached a diagram of potential new wiring - is this correct? - wire from the Twin socket into the Boiler FCU Live, Neutral & Earth Supply connections??

And terminal block connect the incoming 32A ring supply to the HOB FCU??

Yes. The 20A circuit is a 'radial', and you can feed multiple accessories (within reason) by daisy-chaining them. It's not the same as a ring.
So you connect the twin socket to the 2.5mm cable going into the boiler fcu, not the fused output of the fcu.
Live coming into fcu goes to live of twin socket, etc.

And then that fcu is left feeding the boiler exactly as it was before, same fuse, unchanged wiring on the output.

 

[brianmoooore]

Do we know if the boiler spur circuit is RCD protected?

 

[advicewelcom]

Do we know if the boiler spur circuit is RCD protected?

Yes, RCD off and no supply goes to boiler.

 

[DPG]

Yes, RCD off and no supply goes to boiler.

Are the circuits in question protected by an RCD though?

 

[advicewelcom]

If you have a bit of spare 3 core wiring in which the earth does not have a sleeve, is that okay to use to connect the twin socket to the boiler FCU?

 

[westward10]

As already stated whilst forum is happy to help the DIYer it has to draw the line at step by step guidance. This task is way out of your comfort zone and the pic in #51 demonstrates this because the back box with the block connectors floating about in it is no longer earthed. Because you have interfered with the existing wiring you now have an rcd tripping with no idea as to why so I suggest you reinstate what you have altered and call an electrician.

 

[advicewelcom]

As already stated whilst forum is happy to help the DIYer it has to draw the line at step by step guidance. This task is way out of your comfort zone and the pic in #51 demonstrates this because the back box with the block connectors floating about in it is no longer earthed. Because you have interfered with the existing wiring you now have an rcd tripping with no idea as to why so I suggest you reinstate what you have altered and call an electrician.

Needs must, there is a pandemic on and not allowed to bring others in, moreover its turkey time soon.

Not sure your analysis is on the mark as rewired it with a bit of 3core and RCD was fine. I suspect the Neutral and Earth were touched in first attempt (which I understand trips RCD).

(PIC ATTACHED) It don't look pretty, I assume I need a bit of neutral sleeving, perhaps wrap the terminal block up in insulation tape, and feed the connecting wire through the back box hole instead?

Just hoping its connected okay and experts on this group are happy with it - as have an oven to order. So very happy and thankful if its gets a thumbs up with any changes needed?

 

[westward10]

That box is not earthed. It would be unwise to advise you further you need an electrician covid or not to assess your situation.

 

[advicewelcom]

That box is not earthed. It would be unwise to advise you further you need an electrician covid or not to assess your situation.

Dying of Covid is nothing we can do about on this forum, dying from electrical shock is ;-) Good suggestion, I can fit a fly lead but looks like its been discussed quite a bit and seems not required by the regs as earthing happens through the lug for recessed back boxes (@ 2:22). Looks more applicable for surface mounted boxes.

 

[telectrix]

Dying of Covid is nothing we can do about on this forum, dying from electrical shock is ;-) Good suggestion, I can fit a fly lead but looks like its been discussed quite a bit and seems not required by the regs as earthing happens through the lug for recessed back boxes (@ 2:22). Looks more applicable for surface mounted boxes.

earthing back boxes was made optional around 2005 under the 16th.however, most of us prefer to earth them for the simple reson that if the faceplate is removed for any reason, you lose the earth through the faceplate oins so the back box could become live if a fault developed.

 

[westward10]

earthing back boxes was made optional around 2005 under the 16th.however, most of us prefer to earth them for the simple reson that if the faceplate is removed for any reason, you lose the earth through the faceplate oins so the back box could become live if a fault developed.

It looks like it is going to be blanked hence it needs an earth. Many electrcians to the exact same thing.