Why Does My Fuse Box Keep Tripping? 6 Common Causes
A trip switch that keeps dropping is your electrical system doing its job: cutting the power before a fault turns into a fire or a shock. The problem is that it keeps happening, and resetting it over and over is not a fix. Here are the most common reasons a consumer unit trips, and how to tell which one you are dealing with.
1. An overloaded circuit
If it trips only when a kettle, heater, washing machine and oven are all running together, the circuit is probably being asked for more current than it is rated for. Unplug a few high-power appliances, reset, and see whether it holds. If it trips again with only one or two items on, the cause is likely something else.
2. A faulty appliance
A failing appliance often trips the circuit the moment it is switched on. Unplug everything on the affected circuit, reset the switch, then plug items back in one at a time. The one that trips it again is your culprit. Leave it unplugged and have it repaired or replaced.
3. A short circuit
A short happens when a live and a neutral conductor touch. It usually trips the breaker instantly and loudly, and can leave scorch marks or a burning smell at a socket or switch. If you smell burning, do not keep resetting it. Leave the circuit off and call an electrician. See our page on electrical burning smells.
4. An earth fault or leakage
RCDs and RCBOs trip when current escapes to earth, for example through damaged cable insulation, a damp socket or a heating element that has failed. Outdoor lighting, garden tools and kitchen appliances are common sources, especially after wet weather. These faults need tracing with proper test equipment.
5. Moisture getting into the system
Water in an outdoor socket, a leaking roof above a light fitting or condensation in a junction box can all cause intermittent tripping. If it only happens when it rains, that is a strong clue.
6. A worn or faulty breaker or RCD
Devices do wear out. An older breaker can become oversensitive and trip below its rated load. This is the last thing to suspect, not the first, because the cause is far more often in the circuit than in the device itself.
What you can check safely
- Note which switch trips and what was running at the time.
- Unplug everything on that circuit, then reset it.
- Reintroduce appliances one at a time to find a faulty one.
- Look for scorch marks, a burning smell or warm sockets. If you find any, stop and call us.
Do not open the consumer unit, bypass a breaker or fit a larger-rated device to stop the tripping. That removes the protection and turns a nuisance into a hazard.
When to call an electrician
Call straight away if the trip is immediate and repeated, if there is a burning smell, crackling or warmth, if water is involved, or if you cannot find the cause after unplugging everything. A qualified electrician can test the circuit, find the fault and certify the repair.
Need help now? Call 020 3411 2027 for a 24-hour response, or read more about our fuse box tripping service.
