Symptoms
- Lights flicker only since the smart switch was installed
- Flicker happens at certain brightness levels
- Flicker with LED bulbs specifically
Likely causes
- CommonIncompatible LED bulbs on a dimmer-style smart switchNot all LED bulbs are dimmable, and mismatched ones flicker on dimmer circuits.
- CommonNo-neutral smart switch using bleeder currentNeutral-free smart switches often pass a tiny current through the bulb to power themselves, which can cause flicker with LEDs.
- PossibleOverloaded or underloaded dimmer circuitDimmers have minimum and maximum wattage ranges that LED bulbs can fall outside of.
- PossibleLoose wiring connection at the switchA poor connection can cause flicker independent of the switch type.
What to do
- Confirm whether your smart switch is a dimmer type and check that installed bulbs are labeled dimmable.
- If using a no-neutral smart switch, check the manufacturer's compatible bulb list, since many require specific LED models or a small bypass capacitor.
- Try a different, known-dimmable LED bulb to see if flicker resolves.
- Check the total wattage of bulbs on the circuit against the switch's minimum and maximum load rating.
- Turn off power and check that wiring connections at the switch are tight.
- If flicker continues with compatible bulbs and secure wiring, consider a different smart switch model better suited to your circuit.
Tools and parts
- Screwdriver
- Non-contact voltage tester
Dimmable LED bulbsSearch: “dimmable LED bulbs compatible with smart switch”
Bypass capacitor for no-neutral smart switchSearch: “smart switch bypass capacitor”
When to call a pro
Call an electrician if flickering continues after trying compatible bulbs, since the circuit or wiring may need evaluation.
Safety
Use caution
Turn off power at the breaker before checking wiring connections at the switch.