Fuses and circuit breakers: what you can reset yourself
The Abimeister team · Updated · 4 min read
Something switches off, and you're standing in front of a consumer unit trying to work out what just happened. Most of the time this is a five-minute fix you can do yourself. Sometimes it isn't, and flicking the switch back up is exactly the wrong move. This guide walks through identifying the tripped circuit, resetting a modern breaker properly, what to do if you've still got old porcelain fuses, the mistake almost everyone makes at least once, and the point where the sensible thing is to leave it off and call someone.
How to tell which circuit tripped
Open the consumer unit and look along the row of switches. A tripped breaker sits in a middle position, or clearly lower than the others — it's not fully up like the rest. On older porcelain fuse boards, the giveaway is different: a small indicator disc or window shows a mark, or the ceramic fuse holder itself looks dark or smells faintly burnt.
Before touching anything, think about what was happening in the flat right before the power went. A kettle, heater, and microwave running at once on the same kitchen circuit is a very common trigger. That single detail usually tells you more than staring at the board does.
If the whole flat has gone dark rather than just one circuit, check whether it's a wider outage first — look at a neighbour's window or the stair light. No point diagnosing your own board if the building or the street has lost power.
Resetting a breaker step by step
First, switch off or unplug whatever was running on that circuit — the kettle, the heater, the extension lead with everything plugged into it. Resetting a breaker with the same load still connected often just trips it again immediately.
Push the switch fully to the off position first, even if it looks like it's already there, then push it firmly up to on. A half-engaged breaker can look reset without actually making contact. If it holds and stays up, wait a moment, then plug things back in one at a time rather than all together.
- Identify and switch off the appliance that was running
- Push the breaker fully off, then firmly back on
- Reconnect appliances one at a time, not all at once
- If it trips again straightaway, stop and don't force it a third time
Porcelain fuses in older panel flats
Many Tallinn panel flats from the Soviet era still have porcelain fuse holders rather than modern breakers — small ceramic cylinders with a fuse wire or cartridge inside, sitting in a row on the board. These don't reset with a switch; the fuse element itself has to be intact, or replaced if it's blown.
If a porcelain fuse has actually blown — the element inside is visibly broken or the holder is scorched — this is not a job to improvise with wire or foil, however common that used to be. A fuse rated too high for the circuit stops protecting anything, which defeats the entire point of having one.
If you don't have a matching spare cartridge fuse of the correct rating on hand, it's simpler and safer to leave it and get an electrician to fit one. This is also a natural point to ask about consumer unit replacement, since boards this age are usually well past their working life and swapping the whole thing removes the porcelain fuse problem for good.
The mistake most people make when resetting a fuse
The most common error is resetting the breaker or fuse repeatedly, hoping it'll eventually hold, without changing anything about what's plugged in. Each trip is the breaker doing its job — cutting power because the current drawn is higher than the circuit is designed for, or because there's a fault somewhere in the wiring or an appliance.
A breaker that trips once with an obvious cause, like two heaters on one socket, is not the same situation as one that trips the moment you reset it with nothing plugged in. The second case points to a fault in the circuit itself, not the load on it, and repeated resetting doesn't fix that — it just delays finding out what's actually wrong.
When to leave the power off and call an electrician
Leave the breaker off and call rather than reset it if it trips again within seconds with nothing plugged into that circuit, if you can smell burning or see scorch marks near the board, or if the switch feels loose, hot, or doesn't stay in position when pushed up.
Also stop if the same circuit trips repeatedly over several days even with normal use, or if you're dealing with a porcelain fuse board and you're not certain of the correct fuse rating — guessing on that point is exactly where things go wrong.
Electrical work in these situations starts from 49 € per hour, and if the board itself is old enough that this keeps happening, a full consumer unit replacement from 350 € per job is often the more sensible long-term fix than repeated call-outs.
Resetting a breaker once with the load removed is normal; resetting it repeatedly without asking why it tripped is the mistake that leads to bigger problems.