When should I worry about a burning electrical smell?

The smells and their meanings: the notorious fishy smell is overheating plastic components, classically a cooked connection behind a socket, switch or in the consumer unit; acrid hot-plastic is cable insulation beyond its temperature; burning dust on first heating of the season is the one benign entry, brief and self-clearing on radiators and heaters.

Why this symptom outranks the others: warmth and flicker are early warnings, but smell means materials are already degrading at temperature. The gap between smelling it and seeing smoke is not a scheduling window; it is luck. Treat the smell as the last polite notice.

The response sequence: nose-locate if quick and safe (warm plate? board? one appliance?), isolate, the appliance unplugged, the circuit off at the board, or the main switch if the source is unclear, and do not re-energise because the smell faded; the damage that made it has not. Anything visibly smoking, scorched at the consumer unit, or unfindable-but-strengthening: 999 first, electrician second. Fire brigades vastly prefer false alarms to the alternative.

What we do on the resulting visit: thermal and electrical inspection of the suspect circuit, the failed connection or accessory found and remade or replaced, and the surrounding circuit tested for collateral heat damage. It is one of the most clearly worthwhile callouts in the trade, and the one where 'it stopped smelling so we left it' is the sentence we most wish people would not say.

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