Symptoms
- Audible buzz or hum from the dimmer or the bulbs themselves
- Buzzing changes pitch or volume as you adjust the dimmer level
- Started after switching to LED bulbs
Likely causes
- CommonDimmer not rated for LED bulbsStandard incandescent dimmers often can't cleanly control the low, variable current LEDs draw, causing an audible buzz.
- CommonTotal bulb wattage below the dimmer's minimum load ratingLED bulbs use very little wattage, and some dimmers need a minimum load to work smoothly.
- PossibleCheap or incompatible LED bulbsEven with a good dimmer, low-quality bulbs can buzz.
- PossibleA loose wire connection at the dimmerWorth ruling out if buzzing happens at all dimmer levels including full on.
What to do
- Check the dimmer's packaging or label to confirm it's LED-compatible.
- Check the total wattage of bulbs it's controlling against the dimmer's minimum load rating.
- Try a different, name-brand dimmable LED bulb to rule out the bulb.
- Replace the dimmer with an LED-rated model if it isn't one already.
- If buzzing happens even at full brightness, turn off the breaker and check for a loose wire at the dimmer.
- Add more bulbs or a compatible add-on if you're below the dimmer's minimum wattage and don't want to replace it.
- Call an electrician if buzzing continues after switching to a compatible dimmer and quality bulbs.
Tools and parts
- Screwdriver
- Non-contact voltage tester
LED-compatible dimmer switchSearch: “LED dimmer switch low wattage compatible”
When to call a pro
Call an electrician if the dimmer buzzes even at full brightness with no dimming, since that can point to a loose connection.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.