In my front room I have 4 wall lights. Each light takes 2 G4 bulbs. I've put some 2.5w dimmable LED bulbs in them and they work fine. However, I want to make them dimmable and currently when I put an LED dimmer switch on the lights just flicker. The only reason I can think this isn't working is because the bulbs need a dimmable LED transformer. There isn't much room in each light fitting in which to put a transformer (5x5x2cm max). There's also barely any room behind the switch.

The only way I can think to do it would be to smash out the knockout box behind the switch and then somehow mount the transformer to the stud wall. Not really sure how I'd achieve that though. Any advice on this would be appreciated.

  • 2
    If they don't presently use a transformer, then adding one isn't going to work. Check what kind of dimming your LEDs support & make sure your dimmer does that kind. (yes there are different kinds of dimming for lights)
    – brhans
    Commented May 10, 2016 at 16:28

1 Answer 1


Some LED's just won't dim, or dim well. If it didn't say dimmable on the package, it probably isn't. G9's are typically 120v, so they shouldn't need a driver unless you bought something that is low voltage (12 or 24v). You may need a better or worse dimmer.

First check with the lamp manufacturer. If they are reputable they will have a list of commonly available Dimmers and the model you should use.

Second check the dimmer doesn't have a minimum load requirement. Many "Smart" dimmers (fade on / fade off / preset types) have a minimum wattage you have to come up to before they will work properly.

If all that pans out, you still could only get a small dimming range. Smaller LED lamps like G9 may only dim about 50% and you may get flickering at it's highest and/or lowest setting.

If there is no suggested dimmer, than try are really cheap slide or dial dimmer. Most cheap LED's were designed to work with the most basic dimmer. If that doesn't work, you may need one of the most expensive ELV type dimmers.

Additionally, some of the better "LED" (aka CL or C-L) dimmers may have trim adjustments to you can limit the dimming slide or dial range to only be responsive to what your lamp can do.

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