For pairing devices with your Internet Bridge, the Bridge has to be in pairing mode. Active pairing mode is indicated by a rapidly flashing pairing LED on the Internet Bridge or of the link LED on the earlier version of the Internet Bridge (without pairing button).
Press the button on the Smart Thermostat for 3 seconds to start pairing, indicated by two moving chain links appearing on the display. When successful, the two chain links stay joint*.
*Older firmware versions might show an antenna symbol instead of chain links. The firmware will update automatically after pairing.
Smart Radiator Thermostat
Press the pairing button above the battery compartment of the Smart Radiator Thermostat for 3 seconds to start pairing, indicated by three lines appearing on the display. Successful pairing is displayed by the three lines turning solid.
Press the button on the top of the Extension Kit for 3 seconds until the LED starts flashing rapidly to start pairing. Successful pairing is indicated by 4x flashing with a pause or a slowly pulsing LED.