Oven, kettle or immersion heater tripping the electrics

Why one appliance can trip the whole house

Ovens, kettles, hobs and immersion heaters all heat water or air with an element. An element is a metal tube with a coiled wire inside, packed in a mineral powder that keeps the live wire away from the metal case. Over time the powder can take in moisture or crack. A small amount of current then leaks from the live wire to the case and on to earth.

Your consumer unit (the modern name for the fuse box) has at least one RCD. RCD stands for residual current device. It compares the current going out on the live wire with the current coming back on the neutral. If some of it is missing, it has gone somewhere it should not, and the RCD switches off in a fraction of a second. That is why a faulty kettle can take out every socket on one side of the house.

If the trip comes from an MCB instead (a single circuit breaker, one of the narrow switches), the cause is more often too much load or a short circuit. Our guide to why electrics keep tripping explains how to tell the two apart.

How to prove which appliance it is

You can usually find the culprit yourself without touching any wiring.

1. Switch off and unplug everything on the circuit that tripped. For an oven or hob, switch off its cooker switch (the large wall switch near the cooker).
2. Reset the RCD or breaker at the consumer unit.
3. Plug or switch things back on one at a time, waiting a minute between each.
4. When the trip happens again, the last thing you switched on is the most likely cause.

Some faults only show when the element is hot. If the oven trips the electrics after ten minutes rather than straight away, let it run with the door shut and watch. If the trip only happens after a clean, wait a day. Water from cleaning can sit around the element terminals and dry out on its own. If it still trips once dry, the element or wiring behind the back panel needs testing.

Do not take the back off an oven or open the immersion heater cover yourself. Both have live terminals behind them.

Which appliance and what it usually means

What trips	Most common cause	What we check
Kettle	Worn element or water in the base	Swap test with another kettle, then the socket
Oven when heating up	Fan oven or grill element leaking to earth	Insulation test on each element
Oven after cleaning	Moisture at terminals	Dry out, then test again
Hob	Cracked ceramic top or damp under rings	Isolation and insulation tests
Immersion heater	Element breaking down, often after years of hard water	Insulation test, check of the switch and flex outlet
Washing machine or dishwasher	Heater element or pump	Run without heat, test the element

An insulation test means putting a higher test voltage on the wiring or element with a special meter and measuring how well it holds. A healthy element shows a very high reading. A failing one shows a low reading. It is the test that turns guesswork into proof.

Immersion heaters in Romford and Havering

Havering is unusual for London. Only 4.9% of homes there were built before 1919, while 35.2% went up between 1945 and 1972 and another 35.6% between the wars, according to the VOA council tax stock of properties for 2025. It also has the highest share of bungalows in our London areas.

Many of those post war houses and bungalows around Harold Hill, Hornchurch and Collier Row were built with a hot water cylinder in an airing cupboard and an immersion heater as backup. Lots still have one, even where a combi boiler now does the daily work. Immersion heaters that sit unused for months and then switch on in a cold snap are a common cause of a sudden RCD trip.

Older airing cupboards can also hide the switch and flex outlet behind towels and boxes. Heat builds up, the cable sheath goes brittle, and the terminals loosen. If you see browning on the switch plate or smell hot plastic in the cupboard, switch the immersion off at its own switch and leave it off. See our page for electricians in Romford and Havering for more on the housing there.

When the appliance is not the problem

Sometimes every appliance passes and the circuit still trips. Then the fault is in the fixed wiring. Common finds include:

• a cooker cable that was nicked when a new kitchen went in
• a damp outside socket on the same RCD
• several small leaks across lots of appliances that together reach the trip level
• an old RCD that has become oversensitive and needs testing or replacing

This is where an electrician carries out proper fault finding on the electrics keep tripping service. We test each circuit separately, record the readings, and tell you what we found before any repair.

What you can safely do while you wait

• Leave the faulty appliance unplugged or switched off at its own switch.
• Reset the RCD so the rest of the house has power.
• Keep fridges and freezers on a circuit that is holding. Move them to another socket if needed.
• If the RCD will not reset even with everything unplugged, leave it off and call an electrician.
• If there is a burning smell, scorch marks or smoke, switch off at the main switch if it is safe to reach and call 999 if there is any sign of fire.

What it costs to fix

We do not publish set prices because the cause decides the work. A kettle is a swap. An oven element is a part and an hour. A cable fault in a wall is a bigger job. Your price is confirmed after a look at the job and the test readings, and you agree it before any work starts.