Short answer
If you see smoke or flame, get everyone out and call 911. A burning smell, a buzzing or crackling sound, or a warm outlet or switch usually means a loose or failing connection, an overloaded device, or a failing breaker, all of which make heat. Unplug what's on it, turn that circuit off at the panel if you can do so safely, stop using it, and call an electrician.
What's Probably Happening
Electricity makes heat where it meets resistance. A good connection has very little. A loose, corroded or damaged one has a lot, and that heat can char insulation, melt plastic and, left alone, start a fire. Smell, sound and warmth are the early warnings.
A Loose Connection at an Outlet or Switch
This is the most common source. A wire that has worked loose under a screw, or a worn push-in connection, heats up under load. The cover plate may feel warm, look brown, or smell like hot plastic. It gets worse with heavy loads like space heaters.
An Overloaded Outlet or Cord
Space heaters, window air conditioners and power strips feeding power strips can pull more than a receptacle or cord is built for. The plug, cord or outlet heats. In Michigan winters, space heaters are the usual suspect.
A Failing Breaker or Panel Connection
A breaker that isn't gripping the bus firmly, or a loose main connection, can buzz, crackle and heat. You may notice a smell near the panel or a breaker that is warm to the touch.
A Fixture or Ballast
Older fluorescent fixtures with failing ballasts can hum loudly and give off a distinct smell as they overheat. Recessed lights with bulbs larger than they're rated for can overheat too.
An Appliance or Its Motor
Sometimes the smell is a motor in a fan, dryer, furnace blower or sump pump. If the smell follows one appliance, unplug it and have it checked.
What You Can Safely Check Yourself
- If there's smoke or flame, stop here. Get everyone out and call 911 from outside.
- Try to locate the smell or sound without touching wiring: a particular outlet, switch, fixture, appliance or the panel.
- Unplug anything in the suspect outlet if you can do it without touching a hot plate or damaged cord.
- If you can reach the panel safely, turn off the breaker for that circuit. Don't open the panel cover.
- Check cords and plugs for melting, discoloration or stiffness. Throw out any that are damaged.
- Test your smoke alarms, and keep that circuit off until it has been checked.
When to Stop and Call
- Smoke, flame, sparks, or a smell you can't locate: get out and call 911.
- Any outlet, switch or cover plate that is warm, discolored, melted or cracked.
- Buzzing, crackling or sizzling at the panel, or a breaker that feels warm.
- A breaker that trips along with the smell or sound.
- The smell comes back after you thought it was gone.
Please don't open the panel, take apart a scorched outlet, or put the circuit back in use to see if it happens again. Once any fire risk is handled, call Select Electric at (989) 835-3587 and tell us where the smell or sound is and what was running when you noticed it.
Common Questions
What does an electrical burning smell smell like?
Often like hot plastic, or a sharp fishy smell from overheating plastic insulation or devices. If you notice it near an outlet, switch, fixture or the panel and can't explain it, treat it as electrical until proven otherwise.
Is a warm outlet normal?
A dimmer switch can feel slightly warm. An outlet or its cover plate should not. A warm or hot outlet usually means a loose connection or an overloaded device. Unplug what's in it and call.
My panel hums. Is that dangerous?
A faint hum can be normal. A loud buzz, crackling, sizzling or a hum that's new or getting louder can mean a loose connection or a failing breaker. Don't open the panel. Keep things away from it and call an electrician.
Should I turn off the breaker if an outlet smells hot?
If you can reach the panel safely and there's no smoke, turning off that circuit is a reasonable step. If there's smoke or flame, don't go to the panel. Get everyone out and call 911.