Why does my electrical cable getting hot inside the wall when the cooker is on – Advice from Electriman, North London Electricians

If you have noticed that the wall feels warm near the cooker cable route, or you can smell a faint burning or plastic smell when the oven or hob is on, this is a warning sign you should not ignore. Here is what is most likely happening and what you should do.

What causes a cable to overheat inside a wall?

The most common reason is that the cable is not big enough to carry the amount of electricity the cooker is drawing. A standard electric cooker in a UK home typically needs a 6mm or 10mm twin and earth cable depending on its rated load. If a previous owner or unqualified person fitted a smaller cable, such as a 2.5mm or 4mm, the cable can overheat under normal cooking use.

A second very common cause is a loose connection, either at the cooker connection unit, at the consumer unit, or at a junction somewhere along the cable route. A loose connection creates resistance, and resistance creates heat. Over time this can cause the insulation to melt, char the surrounding plasterwork, or start a fire inside the wall cavity.

A third cause is the cable running through or under loft insulation. UK Building Regulations and wiring rules require cables to be derated or run in conduit when they pass through insulation, because the insulation stops heat from escaping. If this has not been done, the cable can run dangerously hot even at normal loads.

What you can safely check yourself:

1. Switch off the cooker circuit at the consumer u

Need a qualified electrician in North London?

Electriman covers Mill Hill, Barnet, Finchley, Edgware, Enfield, Watford and surrounding areas. All work is Part P certified and fully insured.