A tripping fuse board is not a fault in itself - it is the safety device working, cutting the power because something downstream is wrong. The trick is finding what, and a calm, methodical check usually points straight at the culprit without an electrician guessing in the dark.
If you see scorching, smell burning, or the board itself is hot, do not keep resetting it. Leave it off and call an electrician.
Find the Offending Circuit
Open the board and see which switch has flipped - a breaker labelled for a circuit, or the main RCD that covers several. The label tells you where to start.
Switch off and unplug the appliances on that circuit, then reset the breaker. If it holds, an appliance is the cause.
Plug the appliances back in one by one. The one that trips it again is your faulty item - stop using it and get it checked.
If the breaker will not reset even with everything unplugged, the fault is in the wiring or the circuit itself - that is an electrician's job.
Common Causes
- A faulty appliance
- The most common cause by far - a failing kettle, washing machine, immersion heater or charger leaking to earth.
- An overloaded circuit
- Too many high-power appliances on one circuit, often through a daisy-chained extension lead.
- Water or damp
- Moisture in an outdoor socket, a bathroom fitting or a leaking appliance trips an RCD instantly.
- A wiring fault
- A damaged cable, a loose connection or a deteriorating circuit - see 7 signs you need an electrician.
RCD vs Breaker - What Tripped?
If a single breaker (MCB) trips, the problem is contained to that one circuit, which makes it easy to isolate. If the RCD trips and takes out several circuits at once, it has detected current leaking to earth somewhere - usually a faulty appliance or water ingress on one of the circuits it protects. The unplug-and-reintroduce method works for both; you are just narrowing down a larger group with the RCD.
When to Stop and Call
- The breaker trips again with everything unplugged
- There is scorching, a burning smell, or heat at the board
- It trips repeatedly with no obvious appliance to blame
- You are not confident working at the consumer unit - that is fine, leave it
If it turns out to be the board itself rather than a circuit, our consumer unit replacement cost guide covers an upgrade, and the emergency electrician cost guide covers call-out rates. If it is sparking, scorched or will not reset, get an emergency electrician on the way.