Your Z-Wave devices must be within the range of the Control Panel in order to communicate with your system. Obstructions between devices (e.g. walls and large appliances) may impact connectivity as well. It is recommended to have a Z-wave device roughly every 30 feet or closer for maximum efficiency. The more devices you have in your z-wave network, the more ‘repeaters’ you have, allowing the Z-wave signal to “hop” through other Z-wave products to reach the destination to be controlled.
To improve the range of your Z-Wave devices, install a Smart Range Extender or another Automation device (e.g. Smart Light Bulb or Smart Plug) in between to allow the z-wave signal to “hop” through to your last desired device.