The Thermostat ORIGINAL only communicates with the Hub in Zigbee. The Hub uses Wi-Fi to communicate with the Internet unit. We recommend placing the Hub at a central point within your home. It does not connect to public Internet access points (hotspots).
Radio range
The Zigbee radio protocol is designed for a range of 100 meters in open space. However, since these are heating products, they are intended exclusively for indoor use.
Consequently, the expected effective range is generally between 10 and 20 meters. This distance strongly depends on the physical environment, varying with the thickness and materials of the walls (reinforced concrete, stone, or metal surfaces drastically reduce the signal, unlike drywall or wood).
The true strength of Zigbee: the mesh network
The theoretical range of a single device is not the limit of your network. Zigbee uses a mesh network topology. This means that every mains-powered device (smart plugs, smart bulbs, wired switches, etc.) acts as a router or "repeater". The signal jumps from one device to another until it reaches the smart home hub (the coordinator).
Advantage: If you have a product 40 meters away from your hub with several walls in between, you simply need to place a few smart plugs or bulbs between them to relay the signal and cover this distance without any issues. A dedicated Zigbee repeater can also be used to extend the range.
Exception: Battery-powered devices (such as radiator valves) are "End Devices". They go into sleep mode to save energy and do not repeat the signal.
Interference factors
Standard Zigbee communicates on the 2.4 GHz frequency band. It therefore shares the same airspace as Wi-Fi, Bluetooth, and even microwave emissions. A congested Wi-Fi channel (such as channel 1, 6, or 11) can reduce the effective range and stability of your Zigbee network if they overlap.
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