When the Internet connection is lost, all the devices are still able to communicate with each other due to the radio signal.
You will not be able to change the temperature values and Time Programs via ViCare application, but all the previously define settings are still in use. The ViCare Smart Climate will continue to work with the latest set temperature values.
All changes introduced to the installation by setting ViCare Thermostats manually will be working as the offline manual mode with a default duration of 2 hours. When the Internet connection is back and secured, those settings will be displayed on your ViCare application as the online manual mode.