Greetings beloved comrades,

I have several lighted ceiling fans of the same model wired with separate, non-dimming, wall switches for the fan and light. The lights inside may be LEDs, but I haven't disassembled them yet to confirm this.

For one of the fans, switching on the fan at the wall causes the light to briefly go out, for maybe a tenth of a second, then come back on.

This strikes me as very strange. I thought maybe the inrush current for the fan was dropping the voltage enough that an LED light might turn off and then recover, but this seems unlikely.

I thought maybe there was a loose connection in the switch that would move when the switch was operated, but tapping/manipulating the switch didn't seem to have the same effect.

Any thoughts before I de-energize the circuit and start testing everything?

  • 3
    Try swapping out the bulbs with another fan and see if the problem follows the bulbs or stays with the fan. – JACK Jan 7 '20 at 17:27
  • A loose connection in the fan connections may also be the issue, the higher current draw causing a voltage drop once the fan is up to speed the voltage returns and the lamp starts working , sounds like a led or cfl type of driver issue caused by a bad connection. – Ed Beal Jan 7 '20 at 17:43
  • Do the fans have separate wires from the switch box for the fan and the light kit, or are they both controlled using a ceiling module? – ThreePhaseEel Jan 8 '20 at 0:57
  • @ThreePhaseEel Separate wires, happily. – Eric Hauenstein Jan 8 '20 at 13:25
  • @JACK It looks like the lighting unit on the fan is a self-contained LED module. I couldn't devote a lot of time to it yesterday, but it doesn't have any obvious ways to open it. I should probably be able to swap the entire lighting unit with another and report back. – Eric Hauenstein Jan 8 '20 at 13:27

This isn't really an answer, but I thought I'd close the loop.

Changing the bulb to a different brand of LED bulb causes the flicker to stop.

This doesn't explain why the flicker is there to begin with, but all of the installed fans of the same model exhibit this behavior.

Ideally, I would investigate further, but time is limited.

  • It's an "answer" in that it identifies the problem and a way to solve it, even if it's not ideal. Please be sure to click the check mark so people with a similar problem in the future know that this one has a workable solution. – FreeMan Jun 26 '20 at 16:09
  • @FreeMan As dirty as it feels to accept my own answer, I have complied. – Eric Hauenstein Jun 27 '20 at 14:33
  • Don't sweat it! Self-answered and accepted are perfectly legitimate at all SE sites. It's one of the things that makes this Q&A site different! – FreeMan Jun 27 '20 at 15:03

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.