Why Does My Oven Keep Tripping the Electrics?

You switch the oven on, there's a click from the consumer unit and half the kitchen goes dark. It's one of the most common reasons people call an electrician. In most cases the protective device, usually an RCD, is doing exactly what it's designed to do: switching off because it has detected current leaking where it shouldn't. The job is to find out where.

RCD or circuit breaker: which tripped?

Open the consumer unit door (not the cover) and look at which switch has moved to off. If it's an RCD, often marked with a "T" or "test" button, the problem is usually leakage to earth. If it's a single circuit breaker (MCB) labelled for the cooker, the circuit has seen too much current, which can point to a short circuit or an overload. Some boards use RCBOs, which combine both on one circuit. Knowing which device tripped helps an electrician find the fault faster, so make a note before resetting anything.

A failing oven element

Oven elements are metal tubes with a heating wire inside, packed in insulating powder. As they age, the outer sheath can crack and the insulation can absorb moisture. Current then leaks from the wire to the metal case and on to earth, and the RCD trips. Grill and fan-oven elements are frequent culprits. Often the oven works on some settings but trips on others, because only one element is faulty.

Moisture and steam

A cooker that trips only when first switched on, or after a deep clean, may have moisture in an element or terminal block. Ovens left unused for a while can absorb damp, especially in cold kitchens. Sometimes the tripping stops once the element has warmed through, but repeated trips are still a sign of deteriorating insulation and shouldn't be ignored.

Kettles, toasters and other appliances

A kettle tripping the electrics is usually the kettle. Worn elements and water seeping into the base are the common causes. Toasters can trip from crumbs touching the elements. A simple test is to unplug every appliance on the circuit, reset, then plug items back in one at a time. If the trip follows one appliance from socket to socket, the appliance is the problem.

Cooker circuit and isolator problems

The cooker has its own circuit, usually with a large isolator switch on the wall and a connection plate behind the appliance. Loose terminals in either can overheat, scorch and eventually fail. Signs include a warm or discoloured switch, a burning smell, buzzing, or the oven cutting out intermittently. Water from a nearby sink or a leaking pipe getting into the outlet plate can also cause tripping. These parts carry high currents, so leave them alone and get them checked.

Safe checks you can make

• Note which device tripped: RCD, cooker MCB or RCBO.
• Switch the cooker off at the isolator, reset the device and see whether it holds with the cooker off.
• If it holds, switch the cooker back on and try one setting at a time: grill, top oven, main oven, hob. Note which one trips it.
• For kettles and small appliances, try them on a different socket and circuit.
• Look, without touching, for scorching or damage at the cooker switch and outlet.

Don't remove covers, open the appliance or keep resetting a device that trips straight away. If there is any burning smell, smoke or heat, switch off at the isolator if safe and call for help.

When to call an electrician

If the trip happens with the cooker isolated, the fault is likely in the fixed wiring rather than the appliance, and needs testing. An electrician can test the circuit, the isolator and the outlet, and confirm whether the oven itself is leaking to earth. If the appliance is at fault, an appliance engineer can replace the element; if you're replacing the cooker, it's a good time to check the circuit is suitable. See our fault finding service, or cooker and hob installation if you're fitting a new one. Call 01235 430442.