How to reset a tripped breaker

Helpful video reference. The embedded clip walks through a modern UK consumer unit and shows the difference between an MCB, an RCD and an RCBO in plain terms. Useful if you are not sure which one has flipped.

1. Find out what has tripped

Look at the board. One switch will be pointing down (OFF) while the others sit up (ON). Note what type:

• MCB — a circuit overload or short. Usually kitchen appliance, shower, oven or immersion.
• RCD (the big one, labelled with a T button) — an earth leak. Usually a failing appliance, damp in an outdoor socket, or water near a socket.
• RCBO — on newer boards, one switch per circuit that does both MCB and RCD jobs.

2. Unplug the high-load suspects

Before resetting, unplug anything that might be at fault on that circuit. Kitchen circuits — unplug kettle, microwave, dishwasher, toaster. Sockets on the ground floor — unplug the washing machine and the tumble dryer. If it is a lighting circuit, turn off the wall switches for every light on that circuit.

3. Try the reset

Push the tripped switch firmly back up to ON. A soft push will not catch the mechanism. If it holds, you have cleared the fault — go to step 4. If it snaps straight back down, stop and go to step 5.

4. Reintroduce appliances one at a time

Plug things back in, one at a time, and switch each on. When the breaker trips, you have found the culprit. Leave it unplugged and either replace it or get it checked — the fault is in the appliance, not the wiring.

5. If the breaker will not reset

That is a live fault in the wiring or a device that is still drawing fault current. Do not keep pushing the switch — a repeatedly closed fault heats contacts and can cause real damage. Leave the circuit off and call a qualified electrician the same day.

Why we keep saying "call"

Repeated trips that reset cleanly with the washing machine unplugged point to a dying appliance. Repeated trips with nothing plugged in point to something wrong in the fixed wiring — loose terminals, damp ingress, a nailed cable — and that is an electrician's job with proper test equipment.