The Smart Thermostat X from tado° is suitable for controlling underfloor heating systems, but there is no specific information on whether it is compatible with the Freecooling function. Compatibility depends on the type of heating system and the communication technology, which is usually via relay or OpenTherm. If your underfloor heating system supports such a connection, the thermostat might work, but it is advisable to clarify the exact compatibility with the manufacturer.