I have new a circuit that I put in during a basement remodel that has a pair of fixtures on a 3-way switch. there is a normal 3-way switch at one end and a 3-way dimmer at the other end.
Installed, everything works fine. Several weeks later, and the solid 3-way only works if the dimmer 3-way is in the ON position. the position of the dimmer slider does not impact things. If the dimmer 3-way is in the OFF position, the solid 3-way does nothing.
I figured that one of the 3-way went bad, so I replaced both switches - and everything is back to normal. I didn't troubleshoot which switch was bad, but I suspect it was the dimmer.
Now, exactly the same problem just occured on a different circuit in the basement.
What gives? Is it really possible that I had two dimmers go bad? These are both the same model lutron switches from Home Depot. Are 3-way dimmers notorious for burning out or something? I did notice that the dimmer switch appears to feel warm to the touch when on.
Before I go our and brute-force another replacement, I'd love a better theory than two bad dimmers :)
Oh - and I carefully marked the common and travellers at install-time, and as this worked for a period then failed - I'm pretty sure the wires aren't mixed up :)
this is the specific model of dimmer:
I'm using the 600 watt incandescent one. The first circuit that burned out had 7 x 50 watt incandencet can lights on it. The second circuit had 2 x 35 watt halogen bulbs.