A breaker keeps tripping: the usual causes

Three reasons a breaker won't stay on

The first and most common cause is simple overload: too many appliances on one circuit drawing more current than the breaker is rated for. This is typical in older flats where a single circuit feeds a kitchen with a kettle, a microwave and a washing machine all wired into the same ring.

The second is a fault in a specific appliance — a short circuit inside a heater, an old washing machine, or a device with damaged wiring. This trips the breaker almost immediately, often within a second or two of switching the appliance on, regardless of what else is running.

The third is a breaker that is simply the wrong rating for the circuit it protects, either because it was replaced with whatever was on hand at the time, or because the circuit's load has grown since it was installed — extra sockets added, a heat pump or an electric hob fitted later.

How to tell which one you have

Switch the breaker back on with everything on that circuit unplugged or switched off. If it holds, start plugging appliances back in one at a time, waiting a minute or two between each. If it trips only once a particular combination is running, or once a certain number of things are on, that points to overload.

If the breaker trips the moment you plug in and switch on one specific appliance, regardless of anything else, that appliance is very likely the fault. Unplug it and leave it unplugged — do not try it again to confirm.

If the breaker trips with nothing plugged in at all, or trips within seconds of being reset with the circuit apparently idle, the fault is more likely in the wiring itself or in the breaker, and this is not something to keep testing by hand.

What not to try yourself

Do not keep resetting a breaker that trips immediately and repeatedly — each reset with an active fault present is a small risk, and it tells you nothing new after the first attempt.

Do not open sockets or switches to inspect wiring, and do not swap the breaker for a higher-rated one to stop the tripping. A higher-rated breaker lets more current through before it cuts off, which removes the protection the circuit is relying on rather than fixing anything.

If you smell burning plastic, see scorch marks around a socket or the consumer unit, or the breaker feels warm to the touch, stop testing and call an electrician. That combination suggests heat has already built up somewhere in the circuit.

• Don't reset a breaker more than once if it trips instantly each time
• Don't open sockets, switches or the consumer unit yourself
• Don't fit a higher-rated breaker to make the tripping stop
• Don't keep testing if you smell burning or see scorch marks
• Do unplug the suspect appliance and leave it unplugged

When the breaker is simply the wrong size

If unplugging appliances shows the circuit tripping under a load that seems entirely reasonable — a kettle and a toaster, say, not six things at once — the breaker may be undersized for what the circuit is actually asked to carry now.

This is common where a circuit's use has changed gradually: a flat rewired decades ago now runs an electric hob, a washer-dryer and several chargers on wiring and a breaker sized for far less. The fix is usually to move some load to a different circuit or to have the circuit's rating properly reassessed, not to force a bigger breaker onto old wiring.

This is electrical work and needs a qualified electrician to check what the cable itself can safely carry before any breaker is changed. We do this kind of assessment and rewiring as electrical work, from 49 € per hour.

When the fault is in the consumer unit itself

In older Soviet-era panel flats and some 1930s wooden houses, the consumer unit may still have breakers, or a full board, that predates the current wiring and appliances entirely. If tripping happens across several circuits, or the same breaker trips no matter what is connected to it, the fault may be the breaker or the board rather than anything downstream.

This is worth flagging to a korteriühistu if it affects a shared riser or a board serving more than one flat, since the fix may need coordinating with the building rather than just your own unit.

A consumer unit that is old, undersized for the flat's current load, or has breakers that no longer trip reliably is usually best replaced outright rather than patched breaker by breaker. We do consumer unit replacement as a fixed job from 350 €, quoted after seeing the existing board.