I have two dimmers which control 500 incandescent lights. Now I need to replace the lights with LEDs.

Can I use the same dimmers?


I got my son a good brand of LED A lamps that says dimmable. When we use a regular dimmer they dim, but not like a regular lamp. When you dim them with a regular dimmer you might not get the same dim from time to time, and on ours the dimming is through but you have have the slide to go. We put these LED's in his fan lights at home and he keeps the full bright.

I know dealers of some of the retrofit LED trims and most of them say use the regular dimmer, but the main reason for that is so you don't have to buy new dimmers when replacing the lamps with LEd's.

Lutron makes a dimmer in the C.L family line that dims LED's and CFL's. These dimmers have a little trim screw dial that you can adjust to lengthen the dimming portion of the dimmer and you set it to be a full range dim on the dimmer.

C.L Family Dimmers

Older electricians will probably remember the trim setting from older ceiling fans and adjusting them to the full range to tell you if it is on or off. the fan motor would still turn the blades until it is clicked off.

The picture tells you what they look like and what you can dim with them. The 3 way version of this is the same price as a plain incandescent dimmer, so that is what we use for both 3 way incandescent and 1p or 3way LED or CFL dimming.


Simple answer is NO. There are LEDs on the market that can be dimmed and actually a few that will work with a standard dimmer. The difference is in the internal LED control and how line voltage is handled to supply the needs of the LED. Go to a good electrical supply store and they can give you accurate information and some different choices.

  • You can dim LEDs very nicely with a 12Volt dimmer. You put it in after the transformer. Full range, looks great. can even run three color LED to mix custom colors.
    – Trout
    Jan 12 '12 at 2:42

I continue to use a standard dimmer to control a track light set with 9 LED bulbs (18W each) and the 10th bulb is a standard 75W incandescent spot light bulb. Without the incandescent bulb, the dimmer range for the LED spot lights is very narrow as predicted; with the incandescent bulb included, it appears to provide full dimmability of the entire set. I believe it is because the single incandescent bulb keeps a steady voltage level from which the LED's rapid-switching circuitry can operate without going to a full-off position in the half cycle over which they operate.


They don't control as well as the new dimmers that are designed for LEDs and it will also drastically shorten the life span of the bulbs. With old incandescents you are just reducing the voltage across the element but with LEDs you are lowering the voltage to the electronics which fire the LED. It's like low voltage to your TV or stereo is not good. Unfortunately the new dimmers for LEDs and CFLs are still quite expensive.

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