Burning Smell from Switchboard? Causes and What to Do
May 5, 2025
You’re midway through cooking dinner when a sharp, acrid whiff sneaks up on you—no smoke, just that telltale burning smell. It jerks you towards the switchboard tucked away in your garage (or under the bench), and suddenly your heart’s racing. In Australia’s scorching summers and downpouring winters, our electrical systems work overtime—and a stray scent can be their SOS.
This isn’t just “dust meeting heat.” It could be overloaded circuits, loose wiring, or tired components edging towards failure. In the next few minutes, we’ll pinpoint the usual culprits, explain why you must act fast, and show you exactly what to do (and who to call) to keep your home safe. Let’s dive in.
What Causes a Burning Smell from the Switchboard?
Whether you live in a heritage Queenslander with ceiling-high air-cons and a cellar-style switchboard or a brick veneer home in Perth battling 40 °C summer days, our uniquely Australian conditions put extra strain on household circuits.
Overloaded Circuits
When too many appliances pull power from a single circuit, wires heat up and insulation can start to melt. In Australia, peak summer demands (think air conditioners, pool pumps, fridges) can easily push circuits past their limit. Look out for:
Multiple high-draw appliances running on the same breaker (e.g., kettle + microwave + toaster)
Old wiring not rated for modern loads
Frequent tripping of that circuit’s breaker
Faulty Wiring
Age, substandard installation, or DIY fixes can all lead to wiring that no longer meets safety standards. Faulty wiring often shows up as:
Discolored or charred insulation around cables
Intermittent power in outlets and lights
Flickering lights when you switch on heavy appliances
Loose Connections
Even a tiny gap where wires meet terminals can create arcing—mini sparks that burn surrounding insulation over time. Signs of loose connections include:
Sporadic loss of power on certain circuits
Crackling or buzzing noises from the switchboard
Warm switchboard cover when you touch it (carefully!)
Circuit Breaker Issues
Circuit breakers are your first line of defence—but if they’re worn out, they may not trip when they should. Faulty breakers can:
Fail to protect against overloads or short circuits
Trip too late, allowing overheating to occur
Remain “half-on”, creating resistance that burns
Component Failure
Switchboards contain fuses, residual-current devices (RCDs), surge protectors and busbars. Any one of these can degrade with age or surge damage:
Busbar corrosion causing heat buildup at contact points
Pests and Debris
Insects, rodents and dust bunnies love the dark, sheltered space behind a switchboard. Their activity can:
Chew through insulation, exposing live conductors
Nest on wiring, trapping heat-producing debris
Leave droppings that conduct electricity and cause arcing
Moisture Ingress
Dampness from leaks or high humidity can undermine electrical safety:
Rusty terminals increasing resistance and heat
Water-dropped insulation that emits a sharp, acrid odour when heated
Triggering RCDs repeatedly as moisture conducts stray currents
Knowing what can go wrong is only half the battle. Now that we’ve pinpointed the usual culprits behind that telltale burning scent, let’s turn our attention to the warning signs that show when it’s time to hit the panic button—before small sparks become big trouble.
Signs the Burning Smell Is a Serious Problem
When it comes to electrical systems, a burning smell emanating from your switchboard is often a sign of a potentially serious issue that requires immediate attention. Ignoring such signs can lead to hazardous situations, including electrical fires, property damage, and even personal injury. Here are the key indicators that the burning smell is a serious problem and warrants prompt action:
Persistent Burning Odour
When the scent lingers long after you’ve turned off your appliances, it’s a red flag.
Odour returns even after airing out the switchboard area
Every time you use certain circuits, the smell comes back
Smell seems stronger over days or weeks
Visible Smoke or Discoloration
You shouldn’t see any smoke or dark marks on and around your switchboard.
Thin wisps of smoke escaping from panel gaps
Yellowing or browning on plastic components or nearby walls
Black soot around breakers, switches or fuse holders
Frequent Tripping of Circuit Breakers
A breaker that trips once in a blue moon is normal—but if yours is constantly cutting out, it’s a clear distress signal. Look for these streamlined indicators:
Overload or Sensitivity: Trips under moderate loads (e.g., running the air-con alongside the fridge), or even when you switch on a single light.
Mechanical Wear & Stickiness: Breakers that “stick” in the off position, resist resetting, or make a buzzing sound when you try.
Persistent Fault Conditions: Repeated trips on the same circuit—no matter the appliance—often point to a wiring fault, moisture issue or internal breaker failure.
Unusual Sounds
Electrical systems should hum quietly or remain silent. Crackles, buzzes or pops are never a good sign.
Crackling when switches flick on or off
Buzzing that grows louder over time
Popping or clicking inside the panel
Heat Emission from the Switchboard
A certain warmth is fine, but anything hot to touch signals overheating.
Switchboard cover feels hot—proceed with extreme caution
Warm spots when running heavy loads, like air conditioners
Heat increases progressively as you reset breakers
Flickering Lights or Power Fluctuations
Instability in your household power can point back to the switchboard.
Lights dimming when other appliances turn on
Momentary outages in parts of the house
Voltage spikes that cause appliances to buzz or hum
Burn Marks or Melting
Physical damage is the most unmistakable sign you’ve let things go too far.
Cracked or warped plastic around breakers or fuse holders
Melted insulation on wires
Burn scars on busbars or terminal blocks
Loss of Power
A sudden blackout on one or more circuits often follows unchecked overheating.
Entire circuits go dead without warning
Partial power loss, such as power outlets that no longer work
Household “blips” when heavy loads draw electricity
What to Do When You Smell Burning at the Switchboard
A burning smell at your switchboard is a flashing warning light—you need to act calmly but swiftly. Here’s your checklist for keeping everyone safe and stopping small sparks from turning into big problems:
Cut the Power (Safely)
Locate your main switch or isolator and turn it off. This kills electricity to the entire home and prevents further overheating.
If you can’t reach the switch safely—or you suspect live wires are exposed—skip to step 3.
Avoid DIY Repairs
Never poke around inside the switchboard yourself. Even a simple screwdriver slip can cause a fatal shock.
Take a quick photo of any visible damage—discoloration, melt marks or loose wiring—so your electrician can diagnose faster.
Note the time, date and any appliances you were running when the smell appeared.
Stay Nearby—but at a Safe Distance
Wait in a safe part of the property (or neighbour’s place) until help arrives.
Don’t power any appliances back on; let the electrician perform thorough testing.
Plan for a Switchboard Service or Upgrade
If your board is old, under-sized or packed with fuses, consider a professional switchboard upgrade—especially if you’re adding big draws like air-con, spa pumps or EV chargers.
Modern switchboards with surge protection and RCDs give you better fault detection and peace of mind.
How Switchboard Problems Are Found and Fixed
Uncovering and resolving switchboard issues is a methodical process—and when done by a qualified electrician, it’s surprisingly straightforward. Here’s how professionals in Australia track down the culprit and restore safe, reliable power to your home:
Tell Your Electrician What You’ve Noticed
Describe exactly when you first smelled or heard something odd.
List which appliances were running and any recent upgrades (like a new air-con or EV charger).
Let Them Inspect Visually (with Power Isolated)
You’ll watch as they remove the cover and point out any burn marks, discolored insulation or pest nests.
Note which components they flag as aged or damaged.
Walk Through Thermal Imaging Results
You’ll see “hot spots” on an infrared camera display—areas where connections are loose or wires are overloaded.
Compare those heat readings from one circuit to the next with their guidance.
Observe the Electrical Tests
You’ll learn how they check insulation resistance, earth leakage and breaker trip times.
Watch them measure voltage under load so you understand what “normal” looks like.
Agree on Repairs and Replacements
You’ll decide whether to tighten connections, swap out burnt fuses or replace old breakers.
Seal any gaps to keep pests and moisture out.
Confirm Safe Operation
You’ll see them re-energise the board, retest every circuit and verify that the fault is gone.
Ask for a final walkthrough of your new surge protection or RCD setup.
Review Their Report and Next Steps
You’ll receive clear notes on what was fixed, plus any upgrade recommendations.
Schedule your next switchboard service or plan for a full upgrade if needed.
Don’t wait for sparks or smoke to force your hand. If you’ve noticed any unusual odours, sounds or heat around your switchboard, switch off your main power (if it’s safe), clear the area and book a professional inspection today. A quick service or upgrade could save you sleepless nights, surprise repair bills and, most importantly, keep your family safe under the one roof that matters most.
Spotted anything unusual? Switch off your main power, clear the area, and book your A-grade electrician today. Your home—and peace of mind—can’t afford to wait.
