z-Wave failure

[barrygordon]

I have four Z-Wave devices, two identical thermostats and two motion/general sensors. When I got up this AM I noticed that neither sensor was working. It would flash its light when detected motion but the ISY was not reacting (One sensor opens a set of motorized pocket doors so it is easy to see if it is working). Investigating further i discovered that there was no communications between the thermostats and the ISY.  The thermostats are working with the HVAC system but that is a direct connection.  It appears that the entire Z-Wave network has stopped working.  I can change parameters at the ISY, the ISY shows the change, the thermostat does not. I can change values at the thermostat but the ISY does not show the change.  What is the best way to ascertain if there is an ISY hardware failure or what is going on so I can get things working again properly.

[asbril]

30 minutes ago, barrygordon said:

I have four Z-Wave devices, two identical thermostats and two motion/general sensors. When I got up this AM I noticed that neither sensor was working. It would flash its light when detected motion but the ISY was not reacting (One sensor opens a set of motorized pocket doors so it is easy to see if it is working). Investigating further i discovered that there was no communications between the thermostats and the ISY.  The thermostats are working with the HVAC system but that is a direct connection.  It appears that the entire Z-Wave network has stopped working.  I can change parameters at the ISY, the ISY shows the change, the thermostat does not. I can change values at the thermostat but the ISY does not show the change.  What is the best way to ascertain if there is an ISY hardware failure or what is going on so I can get things working again properly.

Zwave works best with a minimum number of  non-battery devices.  What that minimum is does depend on the distance between these devices and the ISY hub. I have close to 60 Zwave devices and a perfectly working Zwave mesh network. Of course you don't need that many devices for your system to work better, but I suggest that you add a few plug-in modules (such as  https://smile.amazon.com/GoControl-Z-Wave-Plug-Dimmer-Module/dp/B00E1OXK3A/ref=sr_1_30?ie=UTF8&qid=1525867673&sr=8-30&keywords=zwave    or https://smile.amazon.com/Individually-Appliance-SmartThings-Compatible-Inovelli/dp/B01K6J1Y1I/ref=sr_1_3?s=hi&ie=UTF8&qid=1525867753&sr=1-3&keywords=zwave+inovelli&dpID=416vi6u0YAL&preST=_SY300_QL70_&dpSrc=srch)  strategically placed  in between your hub and your thermostats. Others have suggested to use Zwave sirens but personally I have not used these and the plug-in modules can actually give additional uses.

And don't forget to perform a 'healing'  after adding the additional modules in order to optimize mesh network.

[lilyoyo1]

I agree with Asbril. Without having anything to repeat the signal it's hard to determine if there is something environmental interfering with the signal causing range issues. 

I would bring one of your motion sensors closer to the ISY (those would be easiest to move). Once close, activate it to see if the ISY picks up on the motion. If it does, then you will know it's a range/environmental and not something else.

 

[barrygordon]

My Z-wave network was working perfectly (for over a year) up until this AM.  So I do not believe it is a device count or mesh communications issue.  Since all the devices stopped working at the same time it leads me to strongly believe that it is an ISY issue.  I have a valid backup of the ISY configuration and will probably reload that and if that does not solve the issue I will exclude and reinclude the 4 devices. 

[KSchex]

 I agree with lilyoyo1, as a first step.  That will at least give you a feel for what is happening.   Z Wave communicates on 908.42 mhz.  Possibly you are your neighbor has a new electronic device on or near this frequency that is hampering your system?  Possibly one of your devices has failed with the transmit turned on.  This happened to me when the battery in one of my door sensors got excessively low.