GE 12724 dimmer died on a 300 watt halogen lamp


Had the GE 12724 on a three-way set up with a GE 12723 add-on switch. Worked great for a month and a half then suddenly wont work manually or through the hub. The lamp I use on that switch is a Holmes HL7066MGBL 300 watt lamp with a dimmer built in. The manual dimmer on the lamp itself was left in the full on position the entire time the 12724 switch worked perfectly. But now that the wall switch no longer works, I plugged the lamp into another outlet and noticed the manual dimmer knob on the lamp no longer works. It only works in the full on position so it’s all or nothing.

I’m trying to figure out what caused the 12724 dimmer to die (and whether I should buy another one) and wondering if it had something to do with the manual dimmer on the lamp even though it wasn’t being used?

Any ideas?


Anytime you combine two dimmers of any kind on the same circuit they are liable to confuse each other and you can burn out one or both. This is why you should never put a smart dimmable bulb under the control of a dimmer switch of any kind if the dimmer switch (smart or dumb) controls the current to the Bulb. But it also applies in situations like that when you describe where you have a fixture/desk lamp with a built-in dimmer.

@Navat604 or one of the other electrical experts can say more. But in general if a lamp has a built-in dimmer, the only smart switch you should use with it is a plain on/off switch, not a dimmer.


Thanks for the response. I assumed with the switch burning out and the other dimmer damaged that two dimmers were working against each other somehow. Forgot to mention that the lamp also has a photocell. Not sure if it would have caused any issue.

Now I have to decide whether to replace the dimmer in the lamp (~$15) and install a regular smart switch or bypass the dimmer and photocell on the lamp and install another dimmer wall switch.

Thanks again.