I have been using this switch for about 4 years with no issue. Yesterday it would not turn completely off, it would only dim about halfway. I pulled the air gap, which didn’t help. I tried a full reset, and that didn’t make a difference either. When I looked in hubitat, it said the switch was off, but the lights were still on. I pulled the switch out and disconnected the load to make sure there wasn’t a short or the lights weren’t siphoning power from somewhere else. With the load disconnected, the load terminal measured 120v when the switch was on and 87v with the switch off. I have replaced it with another switch for now. Just wondering if there are any other troubleshooting steps, or is it just a dead switch?
I just benched a LZW31-SN. With no load, surprisingly, I got 89.9 VAC on the load terminal with the switch off. I wasn’t expecting it to be that high.
So your voltage reading may not be out of line. But if you swapped the switch out for an identical one and the new one is working, it would seem the first switch is bad. Strange . . .
I did check it with and without a load, and got between 85-90v with with switch off. I didn’t have another Inovelli switch to replace it with, but I did replace it with another smart switch and didn’t have the same issue. I didn’t take any measurements on the new switch. I thought it was strange you could still use the dimmer from 100 down to 1, but it would only actually dim halfway. Everything on the app reported normal. I have a bench I can run more tests on, I just wasted sure if there was anything else to look at.
I did a little more checking last night. It was still around 87v with no load, but with a load and the switch off, it read around 60v on both the load and traveler terminals at the same time.
From time to time we see reports that an installation that had been working for some time changes to where the bulbs don’t go all the way off. My thoughts have always been that the properties of the bulbs changes over time. I have nothing to substantiate this, it’s just what I’m thinking.
If you could replace with another LZW31-SN, that would determine if it’s the switch.
Or, you could just add a bypass. I know you have a neutral, but there are cases where neutral-installation folks have solved this issue with a bypass.
I tried it with a different fixture, so I don’t think it was the bulbs. The first had three 100w LED bulbs, the second was an led panel. Both exhibited the same behavior.