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    Why Do My Lights Flicker? Harmless Causes vs Real Warning Signs

    Flickering lights range from a cheap LED-dimmer mismatch to a dangerous loose connection. How to tell the difference in your Johannesburg home, and when to call an electrician.

    18 May 2026 6 min read
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    Flickering lights are one of those faults that range from completely trivial to a genuine fire risk — and telling them apart is worth knowing. Here is how to read what your lights are doing.

    The harmless causes

    • LED on the wrong dimmer — many older dimmers were built for halogens and make LEDs flicker or buzz.
    • A brief dim when a big load starts — a geyser, pump or kettle kicking in can cause a momentary dip. Occasional and slight is normal.
    • A loose bulb — sometimes it really is just a bulb not seated properly.

    The warning signs

    Take it seriously if the flicker is widespread, persistent or worsening, or comes with warm switch plates, a burning smell, or buzzing. These point to a loose connection in a socket, switch or the DB board — and loose connections arc, generate heat and start fires.

    The LED fix

    If only your LEDs flicker, the answer is LED-compatible dimmers or correcting the fitting — not reverting to power-hungry halogens. See LED conversion.

    When the geyser dims the lights

    A pronounced or frequent dim when a heavy load starts can mean an overloaded circuit or undersized supply — worth an electrician's check and possibly a DB-board upgrade.

    Not sure?

    If in doubt, get it traced — it is cheap peace of mind against a fire risk. See fault finding or book a callout.

    Frequently Asked Questions

    Common causes are LED bulbs on an incompatible dimmer, normal brief dimming when a heavy appliance like a geyser or pump switches on, a loose bulb or fitting, or — more seriously — a loose connection in the circuit or DB board. Occasional flicker tied to an appliance is usually harmless; persistent or widespread flicker can signal a fault that needs an electrician.

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