Advice on oven supply

[gazdkw82]

Our 4.8KW oven stopped working yesterday so I went about investigating. The fix was pretty easy, the neutral cable had become disconnected at the oven connection point at the back of the oven. However upon fixing this I noticed one of many problems. Firstly the flex 1.0mm t+e cable looks like its seen better days and is undersized for the oven. I fixed the neutral back in and tried the cable out of interest and it got quite warm after about 10 mins of operation.


The flex cable goes down the back of the fitted kitchen units and plugs into a double wall mounted socket which is situated under the units on the back wall. Both the switches on the socket don’t work anymore. The 2.5mm cable supplying this double socket are fed from a 45A double pole switch which is next to the oven. The cable in the switch is a 6mm however the cable that I can see under the units feeding the socket is a 2.5mm so there is a connection of some sorts behind the units. I cannot access this without ripping half the kitchen out. The 2.5mm that comes from behind the unit was sat tangling ontop of the gas pipe supplying the hob. I’m not sure what is the best option here. If I could rip it out I would and have the oven directly wired into the 45A switch and get rid of the socket. However I can’t do this without masses of mess and disruption.


So what I’ve done so far is disconnect double socket, cut the 2.5mm and terminated into a 25A JB which will have to be fixed to the underside of the units to pull the cable away from the gas pipe. I plan to them come from this junction box and fit a new double socket in an accessible place which the oven can then plug into. I’ve made a quick sketch of the situation as its quite difficult to explain.


What would you do? Some advice would be greatly appreciated.

 

[Richard Burns]

A whole range of options here, most of them fixing the problem partially as the full repair would be extensive. (Move cooker switch to new oven position and wire from that). Presumably the oven used to be where the right hand cupboard is located and had a socket or cooker outlet point there.
I woudl initially look behind the right hand cabinet with an inspection camera to see if it is possible to just cut a hole in the side of the cupboard at the place that the cable is jointed and start from there, running 2.5mm² cable to a conveniently placed double socket.

Your solution is OK but does introduce more joints, however a good joint should not fail.

1.0mm² cable or flex really does not sound good, often ovens are wired in 1.5mm² flex which should be fine for the load. Use heat resisting cable or manufacturers recommendation.

 

[gazdkw82]

To move the switch id have to pull cables out of the wall and route them into new position which would mean extensive work. I really don't like the fact that the design will eventually have numerous joints but im not left with many options until maybe the kitchen is changed or I just rip some of it out and change the whole lot.

I was going to use wago's. Are they are preferable to a traditional JB?

 

[Richard Burns]

Since push wire connectors have a spring loaded connection to the cable you can be sure it will not become loose over time like a screw terminal so in general they would be preferable to a screw terminal, though screw terminals definitely have their place.