Dimmed lights go real bright by themselves


Old 10-24-19, 03:08 PM
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Dimmed lights go real bright by themselves

Last night we had company over. We were enjoying coffee in our new sunroom. I had the ceiling can lights (which are on the same circuit as the ceiling fan lightsl) dimmed using a dimmer switch. After a while, the lights suddenly went full bright! The ceiling fan lights then went off completely. I turned off the ights, dimed them again and it happened one more time. Anyt thoughts as to what might cause this? I have dimmable LED lights in the cans and ceiling fan. Thanks.
Old 10-24-19, 05:14 PM
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Hard to imagine this is anything but a bad dimmer. Who made it and is it a led specific model?
Old 10-24-19, 05:59 PM
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Is this happening to any other lights in the house? A loose neutral on the main service line can cause lights to go bright and other to dim.
Old 10-25-19, 07:29 AM
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My guess is the ceiling fan lights were originally incandescent and changed to LEDs along with the dimmer. The ceiling can LEDs have electronic drivers. The drivers have impedance. The ceiling can LEDs and the ceiling fan LEDs dimmer are connected in parallel electrically. Impedances in parallel do not react the same as incandescants in parallel and are sensitive to frequency change. The dimmer operates by changing frequency. My only suggestion is you experiment with different dimmers and LEDs.
Old 11-06-19, 05:11 AM
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Dimmed lights go real bright by themselves

Beelzebob, Joed, and Telecomguy,

Thanks so much for the responses! This gives me something to work with. I'm certain that at least one of your recommendations will do the trick. It has to.

Old 11-06-19, 08:40 PM
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I would also recommend checking the owners manual for the fans and see if it specifically states that LED bulbs can be used. The bulk of ceiling fans can only use incandescent bulbs.
Old 11-06-19, 09:10 PM
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Most (may be all?) ceiling fan dimmers that came with or built into the ceiling fan and did not come with LED bulbs are not compatible with LED bulbs.
Dimmable LED bulb means it is dimmable with compatible dimmers (CL dimmers). LED works differently from a regular incandescent bulbs and requires a special circuit to work.

If your ceiling fan has an external dimmer, you can replace the dimmer with a CL dimmer.
If your ceiling fan has built in dimmer, you are stuck with regular incandescent or halogen bulbs.
Old 11-12-19, 03:36 PM
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Everyone was on the right track

Thanks again to everyone who responded. It turned out that the dimmer I installed worked before because none of the lights were LED. When I installed LED bulbs in the can lights this is where the trouble started. A new dimmer was installed that is LED compatible and was calibrated between the fanlights and the can lights and this solved the problem. Thanks again.

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