Zwave Leviton Reliability issues

Two weeks ago I installed a Leviton DZMX1 to control a set of recessed lights. All worked great for a week, but then I started to have reliability issues. At first I thought maybe it was the dimmer it self, but a new one is having the same issues.

It seems as every so often the dimmer is losing it’s connection with my hub and stops responding until I physically touch the switch to control the lights. 80% of the time, smart things control works again, and the other time it takes more tinkering.

Tonight I worked my way into zwave repair. I reviewed the events log and found that device ID 04, Kitchen Lights, rejoined the network and voila everything worked perfectly again. Fast forward 20 mins when I go to control the lights and much to my dismay, they are not functioning. I reran the zwave repair and touched the switch a few times, they start working again, but 5 minutes later are unreliable.

Could it be bad signal strength? This is my only zwave device, the hub is in my living room which is 50ft away and around a wall. I do have a zigbee LED light strip in the same room as the dimmer and that works reliably 100% of the time.

I’m not sure what the issue is, but it sure is frustrating. Any help is appreciated.

Zigbee only repeats for zigbee, Z wave only repeats for Z wave. So really you can think of those as two different networks. It’s not uncommon that you have things set up so that one protocol is working and the other needs more strengthening.

There are a lot of architectural issues that can dampen signal strength. Foil wallpaper, water pipes, plaster lathing, foil backed insulation inside the wall, mirrors, brick, concrete, etc.

The Leviton devices are reliable, but the current generation is classic Z wave, not zwave plus, and the usual rule of thumb is to have a repeater about every 40 feet in a typical US home. So you’re probably right on the edge. Adding an additional Z wave repeater about halfway between the hub and the switch should help a lot.

See The following for more details:

I have a similar issue. I am using a ST Hub V2 and found that the Zigbee devices are reliable and have a longer range. I am using Ecolink door and window sensors and a bunch of them fail all the time. I also have 2 Wave Plus Leviton devices ( a light switch and a plug in lamp dimmer). The dimmer is struggling to stay connected 30 feet from the hub and there is one slim wall in between. I was hoping to use this dimmer to repeat the z-wave signal for my other levity light switch and my ecolink door sensors but the range is so disappointing I am wondering if I should replace all my z-wave devices with zigbee.

Something is definitely wrong. I use both Z wave and zigbee for different purposes, and like both, but zigbee definitely has a considerably shorter range than Z wave plus. In typical US home construction, you will get about 40 feet for one hop for zigbee, and 60 to 75 feet for Z wave plus.

So there are a couple of possibilities regarding the specific Switch which is having problems.

First, have you run the Z wave repair utility, and if so did you get any error messages from it?

https://support.smartthings.com/hc/en-us/articles/200981864-How-do-I-make-sure-my-Z-Wave-devices-are-routing-optimally-

Second, if your Z wave repair is clean, what is the composition of the wall? A slim concrete, Adobe, or tinted glass wall could create many more signal issues than a much thicker wood wall. Also, foil backed insulation inside the wall or foil wallpaper can be a problem as well.

Third, it’s always possible that it’s just a bad device. It happens. If you have another Z wave plus device that you can easily test nearby, such as a sensor or a plug in pocket socket, you might try that. Again, just remember to run the repair utility after you relocate the device so that all the neighbor tables get up to date. If the new device works fine while the switch still has problems, then maybe it’s just a bad switch.

If the new device also has problems, you may have to look for local sources of interference. Wi-Fi does not interfere with Z wave, but anything in the 900 band can, including some baby monitors and some cordless phones.

You should also get in touch with support, because the Leviton is an officially supported device, and they may be able to see some things from their side that we can’t see as customers.

I am having similar problems. I have a combination of the old Visia rf+ and the new Z-Wave plus devices. I have 30 of these things installed in my home and switches that are literally 3’ away from a working switch fall off the network and either become disconnected or turn on but fail to report status and still appear as off in SmartThings. A Hub reboot succeeded in loosing another switch. When I manage to get everything back on-line, and with these new Leviton switches (DZ15S) I have to literally start over by deleting them from SmartThings IDE (Can’t exclude that which won’t connect), factory reset the switch and re-add them. They might last a day, 3 days or a week, but eventually all these switches will have problems. The hub is 5 ’ from the nearest Z-Wave dimmer (Visia ones), and no switch is more than about 10’ from another Z-Wave device.

Insofar as construction is concerned, I don’t have foil-backed insulation on my interior walls, but there are steel furring strips between the wood ceiling joists and the sheetrock on 16" centers. The walls do not have these. There is lot’s of open space, and very few doors to interfere, so I am pretty much ruling out interference or signal strength as part of the problem. Besides, why won’t the devices pop back online when the issue abates, and why would they work for a week then stop. It just doesn’t make sense unless there is some sort of device health/network reconnect issue in the firmware. Also the fact that multiple switches in different locations have problems and the Vizia dimmers almost never go off-line.

I’ve tried repairing, and I get one mystery device that doesn’t report, but it’s not one of the devices that is having problems. I’ve tried rebuilding the entire network as well. No luck.

Any advice on this would be helpful, especially if we can get a Leviton person to comment.